diff --git a/github/actions_oidc_test.go b/github/actions_oidc_test.go
index 194a821ef95..e1033b4a66f 100644
--- a/github/actions_oidc_test.go
+++ b/github/actions_oidc_test.go
@@ -90,7 +90,7 @@ func TestActionsService_SetOrgOIDCSubjectClaimCustomTemplate(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/oidc/customization/sub", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"include_claim_keys":["repo","context"]}`+"\n")
+		testJSONBody(t, r, `{"include_claim_keys":["repo","context"]}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -122,7 +122,7 @@ func TestActionsService_SetRepoOIDCSubjectClaimCustomTemplate(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/actions/oidc/customization/sub", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"use_default":false,"include_claim_keys":["repo","context"]}`+"\n")
+		testJSONBody(t, r, `{"use_default":false,"include_claim_keys":["repo","context"]}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -155,7 +155,7 @@ func TestActionService_SetRepoOIDCSubjectClaimCustomTemplateToDefault(t *testing
 	mux.HandleFunc("/repos/o/r/actions/oidc/customization/sub", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"use_default":true}`+"\n")
+		testJSONBody(t, r, `{"use_default":true}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
diff --git a/github/actions_permissions_enterprise_test.go b/github/actions_permissions_enterprise_test.go
index 29d61242226..1f9dee84636 100644
--- a/github/actions_permissions_enterprise_test.go
+++ b/github/actions_permissions_enterprise_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestActionsService_UpdateActionsPermissionsInEnterprise(t *testing.T) {
 	input := &ActionsPermissionsEnterprise{EnabledOrganizations: Ptr("all"), AllowedActions: Ptr("selected")}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsPermissionsEnterprise
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled_organizations":"all","allowed_actions":"selected"}`)
 
 		fmt.Fprint(w, `{"enabled_organizations": "all", "allowed_actions": "selected"}`)
 	})
@@ -143,7 +137,7 @@ func TestActionsService_SetEnabledOrgsInEnterprise(t *testing.T) {
 	mux.HandleFunc("/enterprises/e/actions/permissions/organizations", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_organization_ids":[123,1234]}`+"\n")
+		testJSONBody(t, r, `{"selected_organization_ids":[123,1234]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -260,13 +254,8 @@ func TestActionsService_UpdateActionsAllowedInEnterprise(t *testing.T) {
 	input := &ActionsAllowed{GithubOwnedAllowed: Ptr(true), VerifiedAllowed: Ptr(false), PatternsAllowed: []string{"a/b"}}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/selected-actions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsAllowed
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"github_owned_allowed":true,"verified_allowed":false,"patterns_allowed":["a/b"]}`)
 
 		fmt.Fprint(w, `{"github_owned_allowed":true, "verified_allowed":false, "patterns_allowed":["a/b"]}`)
 	})
@@ -338,13 +327,8 @@ func TestActionsService_UpdateDefaultWorkflowPermissionsInEnterprise(t *testing.
 	input := &DefaultWorkflowPermissionEnterprise{DefaultWorkflowPermissions: Ptr("read"), CanApprovePullRequestReviews: Ptr(true)}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/workflow", func(w http.ResponseWriter, r *http.Request) {
-		var v *DefaultWorkflowPermissionEnterprise
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"default_workflow_permissions":"read","can_approve_pull_request_reviews":true}`)
 
 		fmt.Fprint(w, `{ "default_workflow_permissions": "read", "can_approve_pull_request_reviews": true }`)
 	})
@@ -420,13 +404,9 @@ func TestActionsService_UpdateArtifactAndLogRetentionPeriodInEnterprise(t *testi
 	input := &ArtifactPeriodOpt{Days: Ptr(90)}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/artifact-and-log-retention", func(w http.ResponseWriter, r *http.Request) {
-		var v *ArtifactPeriodOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"days":90}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -492,13 +472,9 @@ func TestActionsService_UpdateSelfHostedRunnerPermissionsInEnterprise(t *testing
 	input := &SelfHostRunnerPermissionsEnterprise{DisableSelfHostedRunnersForAllOrgs: Ptr(false)}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/self-hosted-runners", func(w http.ResponseWriter, r *http.Request) {
-		var v *SelfHostRunnerPermissionsEnterprise
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"disable_self_hosted_runners_for_all_orgs":false}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -573,13 +549,9 @@ func TestActionsService_UpdatePrivateRepoForkPRWorkflowSettingsInEnterprise(t *t
 	}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/fork-pr-workflows-private-repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *WorkflowsPermissionsOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"run_workflows_from_fork_pull_requests":true,"send_write_tokens_to_workflows":false,"send_secrets_and_variables":true}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -645,13 +617,9 @@ func TestActionsService_UpdateEnterpriseForkPRContributorApprovalPermissions(t *
 	input := ContributorApprovalPermissions{ApprovalPolicy: "require_approval"}
 
 	mux.HandleFunc("/enterprises/e/actions/permissions/fork-pr-contributor-approval", func(w http.ResponseWriter, r *http.Request) {
-		var v *ContributorApprovalPermissions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, &input)
-		}
+		testJSONBody(t, r, `{"approval_policy":"require_approval"}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/actions_permissions_orgs_test.go b/github/actions_permissions_orgs_test.go
index c60c99f20e2..47edd2e5726 100644
--- a/github/actions_permissions_orgs_test.go
+++ b/github/actions_permissions_orgs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestActionsService_UpdateActionsPermissions(t *testing.T) {
 	input := &ActionsPermissions{EnabledRepositories: Ptr("all"), AllowedActions: Ptr("selected"), SHAPinningRequired: Ptr(true)}
 
 	mux.HandleFunc("/orgs/o/actions/permissions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsPermissions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled_repositories":"all","allowed_actions":"selected","sha_pinning_required":true}`)
 
 		fmt.Fprint(w, `{"enabled_repositories": "all", "allowed_actions": "selected", "sha_pinning_required": true}`)
 	})
@@ -143,7 +137,7 @@ func TestActionsService_SetEnabledReposInOrg(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/permissions/repositories", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_repository_ids":[123,1234]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[123,1234]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -260,13 +254,8 @@ func TestActionsService_UpdateActionsAllowed(t *testing.T) {
 	input := &ActionsAllowed{GithubOwnedAllowed: Ptr(true), VerifiedAllowed: Ptr(false), PatternsAllowed: []string{"a/b"}}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/selected-actions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsAllowed
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"github_owned_allowed":true,"verified_allowed":false,"patterns_allowed":["a/b"]}`)
 
 		fmt.Fprint(w, `{"github_owned_allowed":true, "verified_allowed":false, "patterns_allowed":["a/b"]}`)
 	})
@@ -380,13 +369,8 @@ func TestActionsService_UpdateDefaultWorkflowPermissionsInOrganization(t *testin
 	input := &DefaultWorkflowPermissionOrganization{DefaultWorkflowPermissions: Ptr("read"), CanApprovePullRequestReviews: Ptr(true)}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/workflow", func(w http.ResponseWriter, r *http.Request) {
-		var v *DefaultWorkflowPermissionOrganization
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"default_workflow_permissions":"read","can_approve_pull_request_reviews":true}`)
 
 		fmt.Fprint(w, `{ "default_workflow_permissions": "read", "can_approve_pull_request_reviews": true }`)
 	})
@@ -462,13 +446,9 @@ func TestActionsService_UpdateArtifactAndLogRetentionPeriodInOrganization(t *tes
 	input := &ArtifactPeriodOpt{Days: Ptr(90)}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/artifact-and-log-retention", func(w http.ResponseWriter, r *http.Request) {
-		var v *ArtifactPeriodOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"days":90}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -537,13 +517,9 @@ func TestActionsService_UpdateSelfHostedRunnersSettingsInOrganization(t *testing
 	input := &SelfHostedRunnersSettingsOrganizationOpt{EnabledRepositories: Ptr("selected")}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/self-hosted-runners", func(w http.ResponseWriter, r *http.Request) {
-		var v *SelfHostedRunnersSettingsOrganizationOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled_repositories":"selected"}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -619,7 +595,7 @@ func TestActionsService_SetRepositoriesSelfHostedRunnersAllowedInOrganization(t
 	mux.HandleFunc("/orgs/o/actions/permissions/self-hosted-runners/repositories", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_repository_ids":[123,1234]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[123,1234]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -745,13 +721,9 @@ func TestActionsService_UpdatePrivateRepoForkPRWorkflowSettingsInOrganization(t
 	}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/fork-pr-workflows-private-repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *WorkflowsPermissionsOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"run_workflows_from_fork_pull_requests":true,"send_write_tokens_to_workflows":false,"send_secrets_and_variables":true}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -817,13 +789,9 @@ func TestActionsService_UpdateOrganizationForkPRContributorApprovalPermissions(t
 	input := ContributorApprovalPermissions{ApprovalPolicy: "require_approval"}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/fork-pr-contributor-approval", func(w http.ResponseWriter, r *http.Request) {
-		var v *ContributorApprovalPermissions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, &input)
-		}
+		testJSONBody(t, r, `{"approval_policy":"require_approval"}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/actions_runners_test.go b/github/actions_runners_test.go
index 49ddca79145..32e1cc709e6 100644
--- a/github/actions_runners_test.go
+++ b/github/actions_runners_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -63,13 +62,8 @@ func TestActionsService_GenerateOrgJITConfig(t *testing.T) {
 	input := &GenerateJITConfigRequest{Name: "test", RunnerGroupID: 1, Labels: []string{"one", "two"}}
 
 	mux.HandleFunc("/orgs/o/actions/runners/generate-jitconfig", func(w http.ResponseWriter, r *http.Request) {
-		var v *GenerateJITConfigRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"test","runner_group_id":1,"labels":["one","two"]}`)
 
 		fmt.Fprint(w, `{"encoded_jit_config":"foo"}`)
 	})
@@ -107,13 +101,8 @@ func TestActionsService_GenerateRepoJITConfig(t *testing.T) {
 	input := &GenerateJITConfigRequest{Name: "test", RunnerGroupID: 1, Labels: []string{"one", "two"}}
 
 	mux.HandleFunc("/repos/o/r/actions/runners/generate-jitconfig", func(w http.ResponseWriter, r *http.Request) {
-		var v *GenerateJITConfigRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"test","runner_group_id":1,"labels":["one","two"]}`)
 
 		fmt.Fprint(w, `{"encoded_jit_config":"foo"}`)
 	})
diff --git a/github/actions_secrets_test.go b/github/actions_secrets_test.go
index 099bad6415d..76c1b1862ad 100644
--- a/github/actions_secrets_test.go
+++ b/github/actions_secrets_test.go
@@ -294,7 +294,7 @@ func TestActionsService_CreateOrUpdateRepoSecret(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/actions/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+		testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -476,7 +476,7 @@ func TestActionsService_CreateOrUpdateOrgSecret(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv=","visibility":"selected","selected_repository_ids":[1296269,1269280]}`+"\n")
+		testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv=","visibility":"selected","selected_repository_ids":[1296269,1269280]}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -556,7 +556,7 @@ func TestActionsService_SetSelectedReposForOrgSecret(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/secrets/NAME/repositories", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_repository_ids":[64780797]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[64780797]}`)
 	})
 
 	ctx := t.Context()
@@ -820,7 +820,7 @@ func TestActionsService_CreateOrUpdateEnvSecret(t *testing.T) {
 	mux.HandleFunc("/repositories/1/environments/e/secrets/secret", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+		testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
diff --git a/github/actions_variables_test.go b/github/actions_variables_test.go
index 473833a4536..f1b0e95808c 100644
--- a/github/actions_variables_test.go
+++ b/github/actions_variables_test.go
@@ -147,7 +147,7 @@ func TestActionsService_CreateRepoVariable(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/actions/variables", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"NAME","value":"VALUE"}`+"\n")
+		testJSONBody(t, r, `{"name":"NAME","value":"VALUE"}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -179,7 +179,7 @@ func TestActionsService_UpdateRepoVariable(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/actions/variables/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"NAME","value":"VALUE"}`+"\n")
+		testJSONBody(t, r, `{"name":"NAME","value":"VALUE"}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -326,7 +326,7 @@ func TestActionsService_CreateOrgVariable(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/variables", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"NAME","value":"VALUE","visibility":"selected","selected_repository_ids":[1296269,1269280]}`+"\n")
+		testJSONBody(t, r, `{"name":"NAME","value":"VALUE","visibility":"selected","selected_repository_ids":[1296269,1269280]}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -360,7 +360,7 @@ func TestActionsService_UpdateOrgVariable(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/variables/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"NAME","value":"VALUE","visibility":"selected","selected_repository_ids":[1296269,1269280]}`+"\n")
+		testJSONBody(t, r, `{"name":"NAME","value":"VALUE","visibility":"selected","selected_repository_ids":[1296269,1269280]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -439,7 +439,7 @@ func TestActionsService_SetSelectedReposForOrgSVariable(t *testing.T) {
 	mux.HandleFunc("/orgs/o/actions/variables/NAME/repositories", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_repository_ids":[64780797]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[64780797]}`)
 	})
 
 	ctx := t.Context()
@@ -642,7 +642,7 @@ func TestActionsService_CreateEnvVariable(t *testing.T) {
 	mux.HandleFunc("/repos/usr/1/environments/e/variables", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"variable","value":"VAR"}`+"\n")
+		testJSONBody(t, r, `{"name":"variable","value":"VAR"}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -674,7 +674,7 @@ func TestActionsService_UpdateEnvVariable(t *testing.T) {
 	mux.HandleFunc("/repos/usr/1/environments/e/variables/variable", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"name":"variable","value":"VAR"}`+"\n")
+		testJSONBody(t, r, `{"name":"variable","value":"VAR"}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/actions_workflow_runs_test.go b/github/actions_workflow_runs_test.go
index 2fdfa6ca519..15df24e5167 100644
--- a/github/actions_workflow_runs_test.go
+++ b/github/actions_workflow_runs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
@@ -1604,13 +1603,8 @@ func TestActionService_PendingDeployments(t *testing.T) {
 	input := &PendingDeploymentsRequest{EnvironmentIDs: []int64{3, 4}, State: "approved", Comment: ""}
 
 	mux.HandleFunc("/repos/o/r/actions/runs/399444496/pending_deployments", func(w http.ResponseWriter, r *http.Request) {
-		var v *PendingDeploymentsRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"environment_ids":[3,4],"state":"approved","comment":""}`)
 
 		fmt.Fprint(w, `[{"id":1}, {"id":2}]`)
 	})
diff --git a/github/actions_workflows_test.go b/github/actions_workflows_test.go
index 0737b5f9393..6d8602db92d 100644
--- a/github/actions_workflows_test.go
+++ b/github/actions_workflows_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -242,13 +241,8 @@ func TestActionsService_CreateWorkflowDispatchEventByID(t *testing.T) {
 		},
 	}
 	mux.HandleFunc("/repos/o/r/actions/workflows/72844/dispatches", func(w http.ResponseWriter, r *http.Request) {
-		var v CreateWorkflowDispatchEventRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, event) {
-			t.Errorf("Request body = %+v, want %+v", v, event)
-		}
+		testJSONBody(t, r, `{"ref":"d4cfb6e7","inputs":{"key":"value"},"return_run_details":true}`)
 
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{"workflow_run_id":1,"run_url":"https://api.github.com/repos/o/r/actions/runs/1","html_url":"https://github.com/o/r/actions/runs/1"}`)
@@ -303,13 +297,8 @@ func TestActionsService_CreateWorkflowDispatchEventByFileName(t *testing.T) {
 		},
 	}
 	mux.HandleFunc("/repos/o/r/actions/workflows/main.yml/dispatches", func(w http.ResponseWriter, r *http.Request) {
-		var v CreateWorkflowDispatchEventRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, event) {
-			t.Errorf("Request body = %+v, want %+v", v, event)
-		}
+		testJSONBody(t, r, `{"ref":"d4cfb6e7","inputs":{"key":"value"},"return_run_details":true}`)
 
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{"workflow_run_id":1,"run_url":"https://api.github.com/repos/o/r/actions/runs/1","html_url":"https://github.com/o/r/actions/runs/1"}`)
@@ -363,13 +352,8 @@ func TestActionsService_CreateWorkflowDispatchEventByID_noRunDetails(t *testing.
 		},
 	}
 	mux.HandleFunc("/repos/o/r/actions/workflows/72844/dispatches", func(w http.ResponseWriter, r *http.Request) {
-		var v CreateWorkflowDispatchEventRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, event) {
-			t.Errorf("Request body = %+v, want %+v", v, event)
-		}
+		testJSONBody(t, r, `{"ref":"d4cfb6e7","inputs":{"key":"value"}}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
@@ -396,13 +380,8 @@ func TestActionsService_CreateWorkflowDispatchEventByFileName_noRunDetails(t *te
 		},
 	}
 	mux.HandleFunc("/repos/o/r/actions/workflows/main.yml/dispatches", func(w http.ResponseWriter, r *http.Request) {
-		var v CreateWorkflowDispatchEventRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, event) {
-			t.Errorf("Request body = %+v, want %+v", v, event)
-		}
+		testJSONBody(t, r, `{"ref":"d4cfb6e7","inputs":{"key":"value"}}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/activity_notifications_test.go b/github/activity_notifications_test.go
index 97011b8c822..3628ec7d426 100644
--- a/github/activity_notifications_test.go
+++ b/github/activity_notifications_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -100,7 +99,7 @@ func TestActivityService_MarkNotificationsRead(t *testing.T) {
 	mux.HandleFunc("/notifications", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"last_read_at":"2006-01-02T15:04:05Z"}`+"\n")
+		testJSONBody(t, r, `{"last_read_at":"2006-01-02T15:04:05Z"}`)
 
 		w.WriteHeader(http.StatusResetContent)
 	})
@@ -124,7 +123,7 @@ func TestActivityService_MarkNotificationsRead_EmptyLastReadAt(t *testing.T) {
 	mux.HandleFunc("/notifications", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{}`+"\n")
+		testJSONBody(t, r, `{}`)
 
 		w.WriteHeader(http.StatusResetContent)
 	})
@@ -143,7 +142,7 @@ func TestActivityService_MarkRepositoryNotificationsRead(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/notifications", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"last_read_at":"2006-01-02T15:04:05Z"}`+"\n")
+		testJSONBody(t, r, `{"last_read_at":"2006-01-02T15:04:05Z"}`)
 
 		w.WriteHeader(http.StatusResetContent)
 	})
@@ -172,7 +171,7 @@ func TestActivityService_MarkRepositoryNotificationsRead_EmptyLastReadAt(t *test
 	mux.HandleFunc("/repos/o/r/notifications", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{}`+"\n")
+		testJSONBody(t, r, `{}`)
 
 		w.WriteHeader(http.StatusResetContent)
 	})
@@ -313,13 +312,8 @@ func TestActivityService_SetThreadSubscription(t *testing.T) {
 	input := &Subscription{Subscribed: Ptr(true)}
 
 	mux.HandleFunc("/notifications/threads/1/subscription", func(w http.ResponseWriter, r *http.Request) {
-		var v *Subscription
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"subscribed":true}`)
 
 		fmt.Fprint(w, `{"ignored":true}`)
 	})
diff --git a/github/activity_watching_test.go b/github/activity_watching_test.go
index 8981cfdd8f0..2db4c2c4545 100644
--- a/github/activity_watching_test.go
+++ b/github/activity_watching_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -194,13 +193,8 @@ func TestActivityService_SetRepositorySubscription(t *testing.T) {
 	input := &Subscription{Subscribed: Ptr(true)}
 
 	mux.HandleFunc("/repos/o/r/subscription", func(w http.ResponseWriter, r *http.Request) {
-		var v *Subscription
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"subscribed":true}`)
 
 		fmt.Fprint(w, `{"ignored":true}`)
 	})
diff --git a/github/admin_orgs_test.go b/github/admin_orgs_test.go
index e2d166895d1..2ebeca4a378 100644
--- a/github/admin_orgs_test.go
+++ b/github/admin_orgs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -23,14 +22,8 @@ func TestAdminOrgs_Create(t *testing.T) {
 	}
 
 	mux.HandleFunc("/admin/organizations", func(w http.ResponseWriter, r *http.Request) {
-		var v *createOrgRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &createOrgRequest{Login: Ptr("github"), Admin: Ptr("ghAdmin")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"login":"github","admin":"ghAdmin"}`)
 
 		fmt.Fprint(w, `{"login":"github","id":1}`)
 	})
@@ -65,14 +58,8 @@ func TestAdminOrgs_Rename(t *testing.T) {
 	}
 
 	mux.HandleFunc("/admin/organizations/o", func(w http.ResponseWriter, r *http.Request) {
-		var v *renameOrgRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		want := &renameOrgRequest{Login: Ptr("the-new-octocats")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"login":"the-new-octocats"}`)
 
 		fmt.Fprint(w, `{"message":"Job queued to rename organization. It may take a few minutes to complete.","url":"https://<hostname>/api/v3/organizations/1"}`)
 	})
@@ -112,14 +99,8 @@ func TestAdminOrgs_RenameByName(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	mux.HandleFunc("/admin/organizations/o", func(w http.ResponseWriter, r *http.Request) {
-		var v *renameOrgRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		want := &renameOrgRequest{Login: Ptr("the-new-octocats")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"login":"the-new-octocats"}`)
 
 		fmt.Fprint(w, `{"message":"Job queued to rename organization. It may take a few minutes to complete.","url":"https://<hostname>/api/v3/organizations/1"}`)
 	})
diff --git a/github/admin_test.go b/github/admin_test.go
index 4756646ac2a..24d0819bd64 100644
--- a/github/admin_test.go
+++ b/github/admin_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -23,13 +22,9 @@ func TestAdminService_UpdateUserLDAPMapping(t *testing.T) {
 	}
 
 	mux.HandleFunc("/admin/ldap/users/u/mapping", func(w http.ResponseWriter, r *http.Request) {
-		var v *UserLDAPMapping
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"ldap_dn":"uid=asdf,ou=users,dc=github,dc=com"}`)
+
 		fmt.Fprint(w, `{"id":1,"ldap_dn":"uid=asdf,ou=users,dc=github,dc=com"}`)
 	})
 
@@ -71,13 +66,9 @@ func TestAdminService_UpdateTeamLDAPMapping(t *testing.T) {
 	}
 
 	mux.HandleFunc("/admin/ldap/teams/1/mapping", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamLDAPMapping
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"ldap_dn":"cn=Enterprise Ops,ou=teams,dc=github,dc=com"}`)
+
 		fmt.Fprint(w, `{"id":1,"ldap_dn":"cn=Enterprise Ops,ou=teams,dc=github,dc=com"}`)
 	})
 
diff --git a/github/admin_users_test.go b/github/admin_users_test.go
index a1a5a37500e..22780997f95 100644
--- a/github/admin_users_test.go
+++ b/github/admin_users_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -20,14 +19,8 @@ func TestAdminUsers_Create(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	mux.HandleFunc("/admin/users", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateUserRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &CreateUserRequest{Login: "github", Email: Ptr("email@example.com"), Suspended: Ptr(false)}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"login":"github","email":"email@example.com","suspended":false}`)
 
 		fmt.Fprint(w, `{"login":"github","id":1}`)
 	})
@@ -92,7 +85,7 @@ func TestUserImpersonation_Create(t *testing.T) {
 
 	mux.HandleFunc("/admin/users/github/authorizations", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"scopes":["repo"]}`+"\n")
+		testJSONBody(t, r, `{"scopes":["repo"]}`)
 		fmt.Fprint(w, `{"id": 1234,
 		"url": "https://example.com/authorizations",
 		"app": {
diff --git a/github/apps_hooks_test.go b/github/apps_hooks_test.go
index 4a002983abf..477262436ec 100644
--- a/github/apps_hooks_test.go
+++ b/github/apps_hooks_test.go
@@ -66,7 +66,7 @@ func TestAppsService_UpdateHookConfig(t *testing.T) {
 
 	mux.HandleFunc("/app/hook/config", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"content_type":"json","insecure_ssl":"1","url":"u","secret":"s"}`+"\n")
+		testJSONBody(t, r, `{"content_type":"json","insecure_ssl":"1","url":"u","secret":"s"}`)
 		fmt.Fprint(w, `{
 			"content_type": "json",
 			"insecure_ssl": "1",
diff --git a/github/apps_test.go b/github/apps_test.go
index b51c7729aa0..06c89114879 100644
--- a/github/apps_test.go
+++ b/github/apps_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -450,14 +449,9 @@ func TestAppsService_CreateInstallationTokenWithOptions(t *testing.T) {
 	}
 
 	mux.HandleFunc("/app/installations/1/access_tokens", func(w http.ResponseWriter, r *http.Request) {
-		var v *InstallationTokenOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, installationTokenOptions) {
-			t.Errorf("request sent %+v, want %+v", v, installationTokenOptions)
-		}
-
 		testMethod(t, r, "POST")
+		testJSONBody(t, r, `{"repository_ids":[1234],"repositories":["foo"],"permissions":{"contents":"write","issues":"read"}}`)
+
 		fmt.Fprint(w, `{"token":"t"}`)
 	})
 
@@ -486,14 +480,9 @@ func TestAppsService_CreateInstallationTokenListReposWithOptions(t *testing.T) {
 	}
 
 	mux.HandleFunc("/app/installations/1/access_tokens", func(w http.ResponseWriter, r *http.Request) {
-		var v *InstallationTokenListRepoOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, installationTokenListRepoOptions) {
-			t.Errorf("request sent %+v, want %+v", v, installationTokenListRepoOptions)
-		}
-
 		testMethod(t, r, "POST")
+		testJSONBody(t, r, `{"repository_ids":null,"repositories":["foo"],"permissions":{"contents":"write","issues":"read"}}`)
+
 		fmt.Fprint(w, `{"token":"t"}`)
 	})
 
diff --git a/github/authorizations_test.go b/github/authorizations_test.go
index bfe893bd833..5dacd1f6836 100644
--- a/github/authorizations_test.go
+++ b/github/authorizations_test.go
@@ -19,7 +19,7 @@ func TestAuthorizationsService_Check(t *testing.T) {
 
 	mux.HandleFunc("/applications/id/token", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"access_token":"a"}`+"\n")
+		testJSONBody(t, r, `{"access_token":"a"}`)
 		testHeader(t, r, "Accept", mediaTypeOAuthAppPreview)
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -56,7 +56,7 @@ func TestAuthorizationsService_Reset(t *testing.T) {
 
 	mux.HandleFunc("/applications/id/token", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"access_token":"a"}`+"\n")
+		testJSONBody(t, r, `{"access_token":"a"}`)
 		testHeader(t, r, "Accept", mediaTypeOAuthAppPreview)
 		fmt.Fprint(w, `{"ID":1}`)
 	})
@@ -93,7 +93,7 @@ func TestAuthorizationsService_Revoke(t *testing.T) {
 
 	mux.HandleFunc("/applications/id/token", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"access_token":"a"}`+"\n")
+		testJSONBody(t, r, `{"access_token":"a"}`)
 		testHeader(t, r, "Accept", mediaTypeOAuthAppPreview)
 		w.WriteHeader(http.StatusNoContent)
 	})
@@ -121,7 +121,7 @@ func TestDeleteGrant(t *testing.T) {
 
 	mux.HandleFunc("/applications/id/grant", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"access_token":"a"}`+"\n")
+		testJSONBody(t, r, `{"access_token":"a"}`)
 		testHeader(t, r, "Accept", mediaTypeOAuthAppPreview)
 	})
 
diff --git a/github/checks_test.go b/github/checks_test.go
index ab0d699609e..477de3fc553 100644
--- a/github/checks_test.go
+++ b/github/checks_test.go
@@ -518,7 +518,7 @@ func TestChecksService_SetCheckSuitePreferences(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/check-suites/preferences", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Accept", mediaTypeCheckRunsPreview)
-		testBody(t, r, `{"auto_trigger_checks":[{"app_id":2,"setting":false}]}`+"\n")
+		testJSONBody(t, r, `{"auto_trigger_checks":[{"app_id":2,"setting":false}]}`)
 		fmt.Fprint(w, `{"preferences":{"auto_trigger_checks":[{"app_id": 2,"setting": false}]}}`)
 	})
 	a := []*AutoTriggerCheck{{
diff --git a/github/code_scanning_test.go b/github/code_scanning_test.go
index c7aaf63b186..1f734713813 100644
--- a/github/code_scanning_test.go
+++ b/github/code_scanning_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -64,17 +63,11 @@ func TestCodeScanningService_UploadSarif(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/code-scanning/sarifs", func(w http.ResponseWriter, r *http.Request) {
-		var v *SarifAnalysis
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "POST")
-		want := &SarifAnalysis{CommitSHA: Ptr("abc"), Ref: Ptr("ref/head/main"), Sarif: Ptr("abc"), CheckoutURI: Ptr("uri"), StartedAt: &Timestamp{time.Date(2006, time.January, 2, 15, 4, 5, 0, time.UTC)}, ToolName: Ptr("codeql-cli")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"commit_sha":"abc","ref":"ref/head/main","sarif":"abc","checkout_uri":"uri","started_at":"2006-01-02T15:04:05Z","tool_name":"codeql-cli"}`)
 
 		w.WriteHeader(http.StatusAccepted)
-		respBody, _ := json.Marshal(expectedSarifID)
-		_, _ = w.Write(respBody)
+		fmt.Fprint(w, `{"id":"testid","url":"https://example.com/testurl"}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/codespaces_orgs_test.go b/github/codespaces_orgs_test.go
index c9b674b7215..307f78045eb 100644
--- a/github/codespaces_orgs_test.go
+++ b/github/codespaces_orgs_test.go
@@ -59,7 +59,7 @@ func TestCodespacesService_SetOrgAccessControl(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o1/codespaces/access", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-		testBody(t, r, `{"visibility":"selected_members","selected_usernames":["u1","u2"]}`+"\n")
+		testJSONBody(t, r, `{"visibility":"selected_members","selected_usernames":["u1","u2"]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -90,7 +90,7 @@ func TestEnterpriseService_AddUsersToOrgAccess(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o1/codespaces/access/selected_users", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"selected_usernames":["u1"]}`+"\n")
+		testJSONBody(t, r, `{"selected_usernames":["u1"]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -120,7 +120,7 @@ func TestEnterpriseService_RemoveUsersFromOrgAccess(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o1/codespaces/access/selected_users", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"selected_usernames":["u1"]}`+"\n")
+		testJSONBody(t, r, `{"selected_usernames":["u1"]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/codespaces_secrets_test.go b/github/codespaces_secrets_test.go
index a2d397d594b..fe87b0cac66 100644
--- a/github/codespaces_secrets_test.go
+++ b/github/codespaces_secrets_test.go
@@ -227,7 +227,7 @@ func TestCodespacesService_CreateOrUpdateSecret(t *testing.T) {
 				mux.HandleFunc("/user/codespaces/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 					testMethod(t, r, "PUT")
 					testHeader(t, r, "Content-Type", "application/json")
-					testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+					testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 					w.WriteHeader(http.StatusCreated)
 				})
 			},
@@ -245,7 +245,7 @@ func TestCodespacesService_CreateOrUpdateSecret(t *testing.T) {
 				mux.HandleFunc("/orgs/o/codespaces/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 					testMethod(t, r, "PUT")
 					testHeader(t, r, "Content-Type", "application/json")
-					testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+					testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 					w.WriteHeader(http.StatusCreated)
 				})
 			},
@@ -263,7 +263,7 @@ func TestCodespacesService_CreateOrUpdateSecret(t *testing.T) {
 				mux.HandleFunc("/repos/o/r/codespaces/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 					testMethod(t, r, "PUT")
 					testHeader(t, r, "Content-Type", "application/json")
-					testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+					testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 					w.WriteHeader(http.StatusCreated)
 				})
 			},
@@ -585,7 +585,7 @@ func TestCodespacesService_SetSelectedReposForSecret(t *testing.T) {
 				mux.HandleFunc("/user/codespaces/secrets/NAME/repositories", func(_ http.ResponseWriter, r *http.Request) {
 					testMethod(t, r, "PUT")
 					testHeader(t, r, "Content-Type", "application/json")
-					testBody(t, r, `{"selected_repository_ids":[64780797]}`+"\n")
+					testJSONBody(t, r, `{"selected_repository_ids":[64780797]}`)
 				})
 			},
 			call: func(ctx context.Context, client *Client) (*Response, error) {
@@ -599,7 +599,7 @@ func TestCodespacesService_SetSelectedReposForSecret(t *testing.T) {
 				mux.HandleFunc("/orgs/o/codespaces/secrets/NAME/repositories", func(_ http.ResponseWriter, r *http.Request) {
 					testMethod(t, r, "PUT")
 					testHeader(t, r, "Content-Type", "application/json")
-					testBody(t, r, `{"selected_repository_ids":[64780797]}`+"\n")
+					testJSONBody(t, r, `{"selected_repository_ids":[64780797]}`)
 				})
 			},
 			call: func(ctx context.Context, client *Client) (*Response, error) {
diff --git a/github/codespaces_test.go b/github/codespaces_test.go
index 9bffbf1a1ca..c3d947e2a02 100644
--- a/github/codespaces_test.go
+++ b/github/codespaces_test.go
@@ -149,7 +149,7 @@ func TestCodespacesService_CreateInRepo(t *testing.T) {
 	mux.HandleFunc("/repos/owner/repo/codespaces", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"ref":"main","geo":"WestUs2","machine":"standardLinux","idle_timeout_minutes":60}`+"\n")
+		testJSONBody(t, r, `{"ref":"main","geo":"WestUs2","machine":"standardLinux","idle_timeout_minutes":60}`)
 		fmt.Fprint(w, `{"id":1, "repository": {"id": 1296269}}`)
 	})
 	input := &CreateCodespaceOptions{
@@ -452,7 +452,7 @@ func TestCodespacesService_CreateFromPullRequest(t *testing.T) {
 
 	mux.HandleFunc("/repos/owner/repo/pulls/42/codespaces", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"machine":"standardLinux","idle_timeout_minutes":60}`+"\n")
+		testJSONBody(t, r, `{"machine":"standardLinux","idle_timeout_minutes":60}`)
 		fmt.Fprint(w, `{"id":1, "repository": {"id": 1}}`)
 	})
 	input := &CreateCodespaceOptions{
@@ -496,11 +496,7 @@ func TestCodespacesService_Create(t *testing.T) {
 
 	mux.HandleFunc("/user/codespaces", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(
-			t,
-			r,
-			`{"pull_request":null,"repository_id":111,"ref":"main","geo":"WestUs2","machine":"standardLinux","idle_timeout_minutes":60}`+"\n",
-		)
+		testJSONBody(t, r, `{"pull_request":null,"repository_id":111,"ref":"main","geo":"WestUs2","machine":"standardLinux","idle_timeout_minutes":60}`)
 		fmt.Fprint(w, `{"id":1,"repository":{"id":111}}`)
 	})
 
@@ -588,11 +584,7 @@ func TestCodespacesService_Update(t *testing.T) {
 
 	mux.HandleFunc("/user/codespaces/codespace_1", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(
-			t,
-			r,
-			`{"machine":"standardLinux","recent_folders":["folder1","folder2"]}`+"\n",
-		)
+		testJSONBody(t, r, `{"machine":"standardLinux","recent_folders":["folder1","folder2"]}`)
 		fmt.Fprint(w, `{"id":1,"repository":{"id":111}}`)
 	})
 
@@ -727,11 +719,7 @@ func TestCodespacesService_Publish(t *testing.T) {
 
 	mux.HandleFunc("/user/codespaces/codespace_1/publish", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(
-			t,
-			r,
-			`{"name":"repo","private":true}`+"\n",
-		)
+		testJSONBody(t, r, `{"name":"repo","private":true}`)
 		fmt.Fprint(w, `{"id":1,"repository":{"id":111}}`)
 	})
 
diff --git a/github/copilot_test.go b/github/copilot_test.go
index aa4e085363c..2e859111279 100644
--- a/github/copilot_test.go
+++ b/github/copilot_test.go
@@ -906,7 +906,7 @@ func TestCopilotService_AddCopilotTeams(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/copilot/billing/selected_teams", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"selected_teams":["team1","team2"]}`+"\n")
+		testJSONBody(t, r, `{"selected_teams":["team1","team2"]}`)
 		fmt.Fprint(w, `{"seats_created": 2}`)
 	})
 
@@ -944,7 +944,7 @@ func TestCopilotService_RemoveCopilotTeams(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/copilot/billing/selected_teams", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"selected_teams":["team1","team2"]}`+"\n")
+		testJSONBody(t, r, `{"selected_teams":["team1","team2"]}`)
 		fmt.Fprint(w, `{"seats_cancelled": 2}`)
 	})
 
@@ -982,7 +982,7 @@ func TestCopilotService_AddCopilotUsers(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/copilot/billing/selected_users", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"selected_usernames":["user1","user2"]}`+"\n")
+		testJSONBody(t, r, `{"selected_usernames":["user1","user2"]}`)
 		fmt.Fprint(w, `{"seats_created": 2}`)
 	})
 
@@ -1020,7 +1020,7 @@ func TestCopilotService_RemoveCopilotUsers(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/copilot/billing/selected_users", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"selected_usernames":["user1","user2"]}`+"\n")
+		testJSONBody(t, r, `{"selected_usernames":["user1","user2"]}`)
 		fmt.Fprint(w, `{"seats_cancelled": 2}`)
 	})
 
diff --git a/github/credentials_test.go b/github/credentials_test.go
index 997c33fc9ec..78f88068fba 100644
--- a/github/credentials_test.go
+++ b/github/credentials_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"errors"
 	"net/http"
 	"testing"
@@ -20,12 +19,9 @@ func TestCredentialsService_Revoke(t *testing.T) {
 		"ghp_1234567890abcdef1234567890abcdef12345678",
 		"ghp_abcdef1234567890abcdef1234567890abcdef12",
 	}
-	expectedBodyBytes, _ := json.Marshal(map[string][]string{"credentials": creds})
-	expectedBody := string(expectedBodyBytes) + "\n"
-
 	mux.HandleFunc("/credentials/revoke", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, expectedBody)
+		testJSONBody(t, r, `{"credentials":["ghp_1234567890abcdef1234567890abcdef12345678","ghp_abcdef1234567890abcdef1234567890abcdef12"]}`)
 		w.WriteHeader(http.StatusAccepted)
 	})
 
diff --git a/github/dependabot_secrets_test.go b/github/dependabot_secrets_test.go
index 69247457a63..72e7fc8d10e 100644
--- a/github/dependabot_secrets_test.go
+++ b/github/dependabot_secrets_test.go
@@ -173,7 +173,7 @@ func TestDependabotService_CreateOrUpdateRepoSecret(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/dependabot/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`+"\n")
+		testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv="}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -355,7 +355,7 @@ func TestDependabotService_CreateOrUpdateOrgSecret(t *testing.T) {
 	mux.HandleFunc("/orgs/o/dependabot/secrets/NAME", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"key_id":"1234","encrypted_value":"QIv=","visibility":"selected","selected_repository_ids":["1296269","1269280"]}`+"\n")
+		testJSONBody(t, r, `{"key_id":"1234","encrypted_value":"QIv=","visibility":"selected","selected_repository_ids":["1296269","1269280"]}`)
 		w.WriteHeader(http.StatusCreated)
 	})
 
@@ -435,7 +435,7 @@ func TestDependabotService_SetSelectedReposForOrgSecret(t *testing.T) {
 	mux.HandleFunc("/orgs/o/dependabot/secrets/NAME/repositories", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Content-Type", "application/json")
-		testBody(t, r, `{"selected_repository_ids":[64780797]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[64780797]}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/dependency_graph_snapshots_test.go b/github/dependency_graph_snapshots_test.go
index 26b77c61584..0650d3198af 100644
--- a/github/dependency_graph_snapshots_test.go
+++ b/github/dependency_graph_snapshots_test.go
@@ -20,7 +20,7 @@ func TestDependencyGraphService_CreateSnapshot(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/dependency-graph/snapshots", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"version":0,"sha":"ce587453ced02b1526dfb4cb910479d431683101","ref":"refs/heads/main","job":{"correlator":"yourworkflowname_youractionname","id":"yourrunid","html_url":"https://example.com"},"detector":{"name":"octo-detector","version":"0.0.1","url":"https://github.com/octo-org/octo-repo"},"scanned":"2022-06-14T20:25:00Z","metadata":{"key1":"value1","key2":"value2"},"manifests":{"package-lock.json":{"name":"package-lock.json","file":{"source_location":"src/package-lock.json"},"metadata":{"key1":"value1","key2":"value2"},"resolved":{"@actions/core":{"package_url":"pkg:/npm/%40actions/core@1.1.9","metadata":{"licenses":"MIT"},"relationship":"direct","scope":"runtime","dependencies":["@actions/http-client"]},"@actions/http-client":{"package_url":"pkg:/npm/%40actions/http-client@1.0.7","relationship":"indirect","scope":"runtime","dependencies":["tunnel"]},"tunnel":{"package_url":"pkg:/npm/tunnel@0.0.6","relationship":"indirect","scope":"runtime"}}}}}`+"\n")
+		testJSONBody(t, r, `{"version":0,"sha":"ce587453ced02b1526dfb4cb910479d431683101","ref":"refs/heads/main","job":{"correlator":"yourworkflowname_youractionname","id":"yourrunid","html_url":"https://example.com"},"detector":{"name":"octo-detector","version":"0.0.1","url":"https://github.com/octo-org/octo-repo"},"scanned":"2022-06-14T20:25:00Z","metadata":{"key1":"value1","key2":"value2"},"manifests":{"package-lock.json":{"name":"package-lock.json","file":{"source_location":"src/package-lock.json"},"metadata":{"key1":"value1","key2":"value2"},"resolved":{"@actions/core":{"package_url":"pkg:/npm/%40actions/core@1.1.9","metadata":{"licenses":"MIT"},"relationship":"direct","scope":"runtime","dependencies":["@actions/http-client"]},"@actions/http-client":{"package_url":"pkg:/npm/%40actions/http-client@1.0.7","relationship":"indirect","scope":"runtime","dependencies":["tunnel"]},"tunnel":{"package_url":"pkg:/npm/tunnel@0.0.6","relationship":"indirect","scope":"runtime"}}}}}`)
 		fmt.Fprint(w, `{"id":12345,"created_at":"2022-06-14T20:25:01Z","message":"Dependency results for the repo have been successfully updated.","result":"SUCCESS"}`)
 	})
 
diff --git a/github/enterprise_actions_runners_test.go b/github/enterprise_actions_runners_test.go
index a8016a4194f..2b70ad1dac0 100644
--- a/github/enterprise_actions_runners_test.go
+++ b/github/enterprise_actions_runners_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -22,13 +21,8 @@ func TestEnterpriseService_GenerateEnterpriseJITConfig(t *testing.T) {
 	input := &GenerateJITConfigRequest{Name: "test", RunnerGroupID: 1, Labels: []string{"one", "two"}}
 
 	mux.HandleFunc("/enterprises/o/actions/runners/generate-jitconfig", func(w http.ResponseWriter, r *http.Request) {
-		var v *GenerateJITConfigRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"test","runner_group_id":1,"labels":["one","two"]}`)
 
 		fmt.Fprint(w, `{"encoded_jit_config":"foo"}`)
 	})
diff --git a/github/enterprise_app_installation_test.go b/github/enterprise_app_installation_test.go
index 766982a28d4..b81617bbf21 100644
--- a/github/enterprise_app_installation_test.go
+++ b/github/enterprise_app_installation_test.go
@@ -137,7 +137,7 @@ func TestEnterpriseService_InstallApp(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/apps/organizations/org1/installations", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"client_id":"cid","repository_selection":"selected","repositories":["r1","r2"]}`+"\n")
+		testJSONBody(t, r, `{"client_id":"cid","repository_selection":"selected","repositories":["r1","r2"]}`)
 		fmt.Fprint(w, `{"id":555}`)
 	})
 
diff --git a/github/enterprise_apps_test.go b/github/enterprise_apps_test.go
index 0c258002bfe..de90318c26c 100644
--- a/github/enterprise_apps_test.go
+++ b/github/enterprise_apps_test.go
@@ -57,7 +57,7 @@ func TestEnterpriseService_UpdateAppInstallationRepositories(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/apps/organizations/o/installations/1/repositories", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"repository_selection":"selected","selected_repository_ids":[1,2]}`+"\n")
+		testJSONBody(t, r, `{"repository_selection":"selected","selected_repository_ids":[1,2]}`)
 		fmt.Fprint(w, `{"id":1, "repository_selection":"selected"}`)
 	})
 
@@ -92,7 +92,7 @@ func TestEnterpriseService_AddRepositoriesToAppInstallation(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/apps/organizations/o/installations/1/repositories/add", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"selected_repository_ids":[1,2]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[1,2]}`)
 		fmt.Fprint(w, `[{"id":1},{"id":2}]`)
 	})
 
@@ -127,7 +127,7 @@ func TestEnterpriseService_RemoveRepositoriesFromAppInstallation(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/apps/organizations/o/installations/1/repositories/remove", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"selected_repository_ids":[1,2]}`+"\n")
+		testJSONBody(t, r, `{"selected_repository_ids":[1,2]}`)
 		fmt.Fprint(w, `[{"id":1},{"id":2}]`)
 	})
 
diff --git a/github/enterprise_billing_cost_centers_test.go b/github/enterprise_billing_cost_centers_test.go
index 5a188fd2d37..c65f1027dc8 100644
--- a/github/enterprise_billing_cost_centers_test.go
+++ b/github/enterprise_billing_cost_centers_test.go
@@ -129,7 +129,7 @@ func TestEnterpriseService_CreateCostCenter(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/cost-centers", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"name":"Engineering Team"}`+"\n")
+		testJSONBody(t, r, `{"name":"Engineering Team"}`)
 		fmt.Fprint(w, `{
 			"id": "abc123",
 			"name": "Engineering Team",
@@ -259,7 +259,7 @@ func TestEnterpriseService_UpdateCostCenter(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/cost-centers/2eeb8ffe-6903-11ee-8c99-0242ac120002", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"name":"Updated Cost Center Name"}`+"\n")
+		testJSONBody(t, r, `{"name":"Updated Cost Center Name"}`)
 		fmt.Fprint(w, `{
 			"id": "2eeb8ffe-6903-11ee-8c99-0242ac120002",
 			"name": "Updated Cost Center Name",
@@ -391,7 +391,7 @@ func TestEnterpriseService_AddResourcesToCostCenter(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/cost-centers/2eeb8ffe-6903-11ee-8c99-0242ac120002/resource", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"users":["monalisa"]}`+"\n")
+		testJSONBody(t, r, `{"users":["monalisa"]}`)
 		fmt.Fprint(w, `{
 			"message": "Resources successfully added to the cost center.",
 			"reassigned_resources": [
@@ -477,7 +477,7 @@ func TestEnterpriseService_RemoveResourcesFromCostCenter(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/cost-centers/2eeb8ffe-6903-11ee-8c99-0242ac120002/resource", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"users":["monalisa"]}`+"\n")
+		testJSONBody(t, r, `{"users":["monalisa"]}`)
 		fmt.Fprint(w, `{
 			"message": "Resources successfully removed from the cost center."
 		}`)
diff --git a/github/enterprise_budgets_test.go b/github/enterprise_budgets_test.go
index faae910c127..e193373a17e 100644
--- a/github/enterprise_budgets_test.go
+++ b/github/enterprise_budgets_test.go
@@ -97,7 +97,7 @@ func TestEnterpriseService_CreateBudget(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/budgets", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"budget_amount":200,"prevent_further_usage":true,"budget_alerting":{},"budget_scope":"enterprise","budget_type":"ProductPricing","budget_product_sku":"actions"}`+"\n")
+		testJSONBody(t, r, `{"budget_amount":200,"prevent_further_usage":true,"budget_alerting":{},"budget_scope":"enterprise","budget_type":"ProductPricing","budget_product_sku":"actions"}`)
 		fmt.Fprint(w, `{
 			"message": "Budget successfully created.",
 			"budget": {
@@ -223,7 +223,7 @@ func TestEnterpriseService_UpdateBudget(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/settings/billing/budgets/b-123", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"budget_amount":10,"prevent_further_usage":false}`+"\n")
+		testJSONBody(t, r, `{"budget_amount":10,"prevent_further_usage":false}`)
 		fmt.Fprint(w, `{
 			"message": "Budget successfully updated.",
 			"budget": {
diff --git a/github/enterprise_code_security_and_analysis_test.go b/github/enterprise_code_security_and_analysis_test.go
index 479c32aa91f..36fd9b0964a 100644
--- a/github/enterprise_code_security_and_analysis_test.go
+++ b/github/enterprise_code_security_and_analysis_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -78,13 +77,8 @@ func TestEnterpriseService_UpdateCodeSecurityAndAnalysis(t *testing.T) {
 	}
 
 	mux.HandleFunc("/enterprises/e/code_security_and_analysis", func(_ http.ResponseWriter, r *http.Request) {
-		var v *EnterpriseSecurityAnalysisSettings
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"advanced_security_enabled_for_new_repositories":true,"secret_scanning_enabled_for_new_repositories":true,"secret_scanning_push_protection_enabled_for_new_repositories":true,"secret_scanning_push_protection_custom_link":"https://github.com/test-org/test-repo/blob/main/README.md","secret_scanning_validity_checks_enabled":true}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/enterprise_codesecurity_configurations_test.go b/github/enterprise_codesecurity_configurations_test.go
index c805968fb36..304f7d616f2 100644
--- a/github/enterprise_codesecurity_configurations_test.go
+++ b/github/enterprise_codesecurity_configurations_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -116,12 +115,7 @@ func TestEnterpriseService_CreateCodeSecurityConfiguration(t *testing.T) {
 	}
 
 	mux.HandleFunc("/enterprises/e/code-security/configurations", func(w http.ResponseWriter, r *http.Request) {
-		var v CodeSecurityConfiguration
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, input) {
-			t.Errorf("Enterprise.CreateCodeSecurityConfiguration request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"config1","description":"desc1","code_scanning_default_setup":"enabled"}`)
 
 		fmt.Fprint(w, `{
 			"id":1,
@@ -225,12 +219,7 @@ func TestEnterpriseService_UpdateCodeSecurityConfiguration(t *testing.T) {
 	}
 
 	mux.HandleFunc("/enterprises/e/code-security/configurations/1", func(w http.ResponseWriter, r *http.Request) {
-		var v CodeSecurityConfiguration
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, input) {
-			t.Errorf("Enterprise.UpdateCodeSecurityConfiguration request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"config1","description":"desc1","code_scanning_default_setup":"enabled"}`)
 
 		fmt.Fprint(w, `{
 			"id":1,
@@ -304,14 +293,8 @@ func TestEnterpriseService_AttachCodeSecurityConfigurationToRepositories(t *test
 
 	mux.HandleFunc("/enterprises/e/code-security/configurations/1/attach", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		type request struct {
-			Scope string `json:"scope"`
-		}
-		var v *request
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-		if v.Scope != "all_without_configurations" {
-			t.Errorf("Enterprise.AttachCodeSecurityConfigurationToRepositories request body scope = %v, want selected", v.Scope)
-		}
+		testJSONBody(t, r, `{"scope":"all_without_configurations"}`)
+
 		w.WriteHeader(http.StatusAccepted)
 	})
 
diff --git a/github/enterprise_manage_ghes_config_test.go b/github/enterprise_manage_ghes_config_test.go
index faf9af4a2f5..afa03526c38 100644
--- a/github/enterprise_manage_ghes_config_test.go
+++ b/github/enterprise_manage_ghes_config_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -597,19 +596,9 @@ func TestEnterpriseService_InitialConfig(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &InitialConfigOptions{
-		License:  "1234-1234",
-		Password: "password",
-	}
-
 	mux.HandleFunc("/manage/v1/config/init", func(_ http.ResponseWriter, r *http.Request) {
-		var v *InitialConfigOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if diff := cmp.Diff(v, input); diff != "" {
-			t.Errorf("diff mismatch (-want +got):\n%v", diff)
-		}
+		testJSONBody(t, r, `{"license":"1234-1234","password":"password"}`)
 	})
 
 	ctx := t.Context()
@@ -629,15 +618,8 @@ func TestEnterpriseService_ConfigApply(t *testing.T) {
 
 	mux.HandleFunc("/manage/v1/config/apply", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		var got *ConfigApplyOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&got))
+		testJSONBody(t, r, `{"run_id":"1234"}`)
 
-		want := &ConfigApplyOptions{
-			RunID: Ptr("1234"),
-		}
-		if diff := cmp.Diff(want, got); diff != "" {
-			t.Errorf("diff mismatch (-want +got):\n%v", diff)
-		}
 		fmt.Fprint(w, `{ "run_id": "1234" }`)
 	})
 
@@ -673,15 +655,8 @@ func TestEnterpriseService_ConfigApplyStatus(t *testing.T) {
 
 	mux.HandleFunc("/manage/v1/config/apply", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "GET")
-		var got *ConfigApplyOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&got))
+		testJSONBody(t, r, `{"run_id":"1234"}`)
 
-		want := &ConfigApplyOptions{
-			RunID: Ptr("1234"),
-		}
-		if diff := cmp.Diff(want, got); diff != "" {
-			t.Errorf("diff mismatch (-want +got):\n%v", diff)
-		}
 		fmt.Fprint(w, `{
 			"running": true,
 			"successful": false,
diff --git a/github/enterprise_manage_ghes_maintenance_test.go b/github/enterprise_manage_ghes_maintenance_test.go
index 73f100f47f3..1ec2ce815b9 100644
--- a/github/enterprise_manage_ghes_maintenance_test.go
+++ b/github/enterprise_manage_ghes_maintenance_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -95,13 +94,8 @@ func TestEnterpriseService_CreateMaintenance(t *testing.T) {
 	}
 
 	mux.HandleFunc("/manage/v1/maintenance", func(w http.ResponseWriter, r *http.Request) {
-		var v *MaintenanceOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled":true,"uuid":"1234-1234","when":"now","ip_exception_list":["1.1.1.1"],"maintenance_mode_message":"Scheduled maintenance for upgrading."}`)
 
 		fmt.Fprint(w, `[ { "hostname": "primary", "uuid": "1b6cf518-f97c-11ed-8544-061d81f7eedb", "message": "Scheduled maintenance for upgrading." } ]`)
 	})
diff --git a/github/enterprise_manage_ghes_ssh_test.go b/github/enterprise_manage_ghes_ssh_test.go
index 3262e0f8647..ee2a7ba634c 100644
--- a/github/enterprise_manage_ghes_ssh_test.go
+++ b/github/enterprise_manage_ghes_ssh_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -54,18 +53,9 @@ func TestEnterpriseService_DeleteSSHKey(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &SSHKeyOptions{
-		Key: "ssh-rsa 1234",
-	}
-
 	mux.HandleFunc("/manage/v1/access/ssh", func(w http.ResponseWriter, r *http.Request) {
-		var v *SSHKeyOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "DELETE")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"key":"ssh-rsa 1234"}`)
 
 		fmt.Fprint(w, `[ { "hostname": "primary", "uuid": "1b6cf518-f97c-11ed-8544-061d81f7eedb", "message": "SSH key removed successfully" } ]`)
 	})
@@ -95,18 +85,9 @@ func TestEnterpriseService_CreateSSHKey(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &SSHKeyOptions{
-		Key: "ssh-rsa 1234",
-	}
-
 	mux.HandleFunc("/manage/v1/access/ssh", func(w http.ResponseWriter, r *http.Request) {
-		var v *SSHKeyOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"key":"ssh-rsa 1234"}`)
 
 		fmt.Fprint(w, `[ { "hostname": "primary", "uuid": "1b6cf518-f97c-11ed-8544-061d81f7eedb", "message": "SSH key added successfully", "modified": true } ]`)
 	})
diff --git a/github/enterprise_properties_test.go b/github/enterprise_properties_test.go
index e94ae903fed..b373e5698c0 100644
--- a/github/enterprise_properties_test.go
+++ b/github/enterprise_properties_test.go
@@ -91,7 +91,7 @@ func TestEnterpriseService_CreateOrUpdateCustomProperties(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/properties/schema", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"properties":[{"property_name":"name","value_type":"single_select","required":true},{"property_name":"service","value_type":"string"}]}`+"\n")
+		testJSONBody(t, r, `{"properties":[{"property_name":"name","value_type":"single_select","required":true},{"property_name":"service","value_type":"string"}]}`)
 		fmt.Fprint(w, `[
 		{
           "property_name": "name",
diff --git a/github/enterprise_rules_test.go b/github/enterprise_rules_test.go
index 724a2e61036..46210ad6d33 100644
--- a/github/enterprise_rules_test.go
+++ b/github/enterprise_rules_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -391,15 +390,7 @@ func TestEnterpriseService_UpdateRepositoryRuleset_OmitZero_Nil(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/rulesets/84", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-
-		var v map[string]any
-		if err := json.NewDecoder(r.Body).Decode(&v); err != nil {
-			t.Errorf("could not decode body: %v", err)
-		}
-
-		if _, ok := v["bypass_actors"]; ok {
-			t.Error("Request body contained 'bypass_actors', expected it to be omitted")
-		}
+		testJSONBody(t, r, `{"name":"test ruleset","source":"","enforcement":""}`)
 
 		fmt.Fprint(w, `{"id": 84, "name": "test ruleset"}`)
 	})
@@ -423,7 +414,7 @@ func TestEnterpriseService_UpdateRepositoryRuleset_OmitZero_EmptySlice(t *testin
 	mux.HandleFunc("/enterprises/e/rulesets/84", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 
-		testBody(t, r, `{"name":"test ruleset","source":"","enforcement":"","bypass_actors":[]}`+"\n")
+		testJSONBody(t, r, `{"name":"test ruleset","source":"","enforcement":"","bypass_actors":[]}`)
 
 		fmt.Fprint(w, `{"id": 84, "name": "test ruleset", "bypass_actors": []}`)
 	})
diff --git a/github/enterprise_scim_test.go b/github/enterprise_scim_test.go
index f38d1a37384..007ee5b6dce 100644
--- a/github/enterprise_scim_test.go
+++ b/github/enterprise_scim_test.go
@@ -478,7 +478,7 @@ func TestEnterpriseService_SetProvisionedSCIMGroup(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Groups/abcd", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"displayName":"dn","externalId":"8aa1","schemas":["`+SCIMSchemasURINamespacesGroups+`"]}`+"\n")
+		testJSONBody(t, r, `{"displayName":"dn","externalId":"8aa1","schemas":["`+SCIMSchemasURINamespacesGroups+`"]}`)
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesGroups+`"],
@@ -542,7 +542,7 @@ func TestEnterpriseService_SetProvisionedSCIMUser(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Users/7fce", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"displayName":"John Doe","userName":"e123","emails":[{"value":"john@example.com","primary":true,"type":"work"}],"externalId":"e123","active":true,"schemas":["`+SCIMSchemasURINamespacesUser+`"]}`+"\n")
+		testJSONBody(t, r, `{"displayName":"John Doe","userName":"e123","emails":[{"value":"john@example.com","primary":true,"type":"work"}],"externalId":"e123","active":true,"schemas":["`+SCIMSchemasURINamespacesUser+`"]}`)
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesUser+`"],
@@ -627,7 +627,7 @@ func TestEnterpriseService_UpdateSCIMGroupAttribute(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Groups/abcd", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"schemas":["`+SCIMSchemasURINamespacesPatchOp+`"],"Operations":[{"op":"replace","path":"displayName","value":"Employees"}]}`+"\n")
+		testJSONBody(t, r, `{"schemas":["`+SCIMSchemasURINamespacesPatchOp+`"],"Operations":[{"op":"replace","path":"displayName","value":"Employees"}]}`)
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesGroups+`"],
@@ -704,7 +704,7 @@ func TestEnterpriseService_UpdateSCIMUserAttribute(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Users/7fce", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"schemas":["`+SCIMSchemasURINamespacesPatchOp+`"],"Operations":[{"op":"replace","path":"emails[type eq 'work'].value","value":"updatedEmail@example.com"},{"op":"replace","path":"name.familyName","value":"updatedFamilyName"}]}`+"\n")
+		testJSONBody(t, r, `{"schemas":["`+SCIMSchemasURINamespacesPatchOp+`"],"Operations":[{"op":"replace","path":"emails[type eq 'work'].value","value":"updatedEmail@example.com"},{"op":"replace","path":"name.familyName","value":"updatedFamilyName"}]}`)
 		w.WriteHeader(http.StatusOK)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesUser+`"],
@@ -809,7 +809,7 @@ func TestEnterpriseService_ProvisionSCIMGroup(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Groups", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"displayName":"dn","members":[{"value":"879d","display":"d1"},{"value":"0db5","display":"d2"}],"externalId":"8aa1","schemas":["`+SCIMSchemasURINamespacesGroups+`"]}`+"\n")
+		testJSONBody(t, r, `{"displayName":"dn","members":[{"value":"879d","display":"d1"},{"value":"0db5","display":"d2"}],"externalId":"8aa1","schemas":["`+SCIMSchemasURINamespacesGroups+`"]}`)
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesGroups+`"],
@@ -901,7 +901,7 @@ func TestEnterpriseService_ProvisionSCIMUser(t *testing.T) {
 	mux.HandleFunc("/scim/v2/enterprises/ee/Users", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeSCIM)
-		testBody(t, r, `{"displayName":"DOE John","name":{"givenName":"John","familyName":"Doe","formatted":"John Doe"},"userName":"e123","emails":[{"value":"john@example.com","primary":true,"type":"work"}],"roles":[{"value":"User","primary":false}],"externalId":"e123","active":true,"schemas":["`+SCIMSchemasURINamespacesUser+`"]}`+"\n")
+		testJSONBody(t, r, `{"displayName":"DOE John","name":{"givenName":"John","familyName":"Doe","formatted":"John Doe"},"userName":"e123","emails":[{"value":"john@example.com","primary":true,"type":"work"}],"roles":[{"value":"User","primary":false}],"externalId":"e123","active":true,"schemas":["`+SCIMSchemasURINamespacesUser+`"]}`)
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{
 			"schemas": ["`+SCIMSchemasURINamespacesUser+`"],
diff --git a/github/enterprise_team_test.go b/github/enterprise_team_test.go
index c300d4affbf..2b870284a7c 100644
--- a/github/enterprise_team_test.go
+++ b/github/enterprise_team_test.go
@@ -83,7 +83,7 @@ func TestEnterpriseService_CreateTeam(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/teams", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"name":"New Team"}`+"\n")
+		testJSONBody(t, r, `{"name":"New Team"}`)
 		fmt.Fprint(w, `{
 			"id": 10,
 			"name": "New Team",
@@ -172,7 +172,7 @@ func TestEnterpriseService_UpdateTeam(t *testing.T) {
 
 	mux.HandleFunc("/enterprises/e/teams/t1", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"name":"Updated Team"}`+"\n")
+		testJSONBody(t, r, `{"name":"Updated Team"}`)
 		fmt.Fprint(w, `{
 			"id": 3,
 			"name": "Updated Team",
diff --git a/github/gists_comments_test.go b/github/gists_comments_test.go
index 63795ff9c20..9ae0aebb2dc 100644
--- a/github/gists_comments_test.go
+++ b/github/gists_comments_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -169,13 +168,8 @@ func TestGistsService_CreateComment(t *testing.T) {
 	input := &GistComment{ID: Ptr(int64(1)), Body: Ptr("b")}
 
 	mux.HandleFunc("/gists/1/comments", func(w http.ResponseWriter, r *http.Request) {
-		var v *GistComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"id":1,"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -222,13 +216,8 @@ func TestGistsService_EditComment(t *testing.T) {
 	input := &GistComment{ID: Ptr(int64(1)), Body: Ptr("b")}
 
 	mux.HandleFunc("/gists/1/comments/2", func(w http.ResponseWriter, r *http.Request) {
-		var v *GistComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"id":1,"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/gists_test.go b/github/gists_test.go
index cb47fecfae1..71e7b106bd8 100644
--- a/github/gists_test.go
+++ b/github/gists_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -485,13 +484,8 @@ func TestGistsService_Create(t *testing.T) {
 	}
 
 	mux.HandleFunc("/gists", func(w http.ResponseWriter, r *http.Request) {
-		var v *Gist
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"description":"Gist description","public":false,"files":{"test.txt":{"content":"Gist file content"}}}`)
 
 		fmt.Fprint(w,
 			`
@@ -547,13 +541,8 @@ func TestGistsService_Edit(t *testing.T) {
 	}
 
 	mux.HandleFunc("/gists/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *Gist
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"description":"New description","files":{"new.txt":{"content":"new file content"}}}`)
 
 		fmt.Fprint(w,
 			`
diff --git a/github/git_blobs_test.go b/github/git_blobs_test.go
index b1a35ac60dd..55f87d6a571 100644
--- a/github/git_blobs_test.go
+++ b/github/git_blobs_test.go
@@ -7,7 +7,6 @@ package github
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -116,15 +115,8 @@ func TestGitService_CreateBlob(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/blobs", func(w http.ResponseWriter, r *http.Request) {
-		var v *Blob
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-
-		want := input
-		if !cmp.Equal(*v, want) {
-			t.Errorf("Git.CreateBlob request body: %+v, want %+v", *v, want)
-		}
+		testJSONBody(t, r, `{"content":"blob content","encoding":"utf-8","sha":"s","size":12}`)
 
 		fmt.Fprint(w, `{
 		 "sha": "s",
diff --git a/github/git_commits_test.go b/github/git_commits_test.go
index 01ce272a0d7..afd82cb77cb 100644
--- a/github/git_commits_test.go
+++ b/github/git_commits_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -182,19 +181,9 @@ func TestGitService_CreateCommit(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/commits", func(w http.ResponseWriter, r *http.Request) {
-		var v *createCommit
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
+		testJSONBody(t, r, `{"message":"Commit Message.","tree":"t","parents":["p"]}`)
 
-		want := &createCommit{
-			Message: input.Message,
-			Tree:    Ptr("t"),
-			Parents: []string{"p"},
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
 		fmt.Fprint(w, `{"sha":"s"}`)
 	})
 
@@ -240,20 +229,9 @@ func TestGitService_CreateSignedCommit(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/commits", func(w http.ResponseWriter, r *http.Request) {
-		var v *createCommit
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
+		testJSONBody(t, r, `{"message":"Commit Message.","tree":"t","parents":["p"],"signature":"----- BEGIN PGP SIGNATURE -----\n\naaaa\naaaa\n----- END PGP SIGNATURE -----"}`)
 
-		want := &createCommit{
-			Message:   input.Message,
-			Tree:      Ptr("t"),
-			Parents:   []string{"p"},
-			Signature: &signature,
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
 		fmt.Fprint(w, `{"sha":"commitSha"}`)
 	})
 
@@ -322,17 +300,10 @@ Commit Message.`
 		Parents: []*Commit{{SHA: Ptr("p")}},
 		Author:  &author,
 	}
-	wantBody := createCommit{
-		Message:   input.Message,
-		Tree:      Ptr("t"),
-		Parents:   []string{"p"},
-		Author:    &author,
-		Signature: &signature,
-	}
-	var gotBody createCommit
 	mux.HandleFunc("/repos/o/r/git/commits", func(w http.ResponseWriter, r *http.Request) {
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&gotBody))
 		testMethod(t, r, "POST")
+		testJSONBody(t, r, `{"author":{"date":"2017-05-04T00:03:43+02:00","name":"go-github","email":"go-github@github.com"},"message":"Commit Message.","tree":"t","parents":["p"],"signature":"my voice is my password"}`)
+
 		fmt.Fprintf(w, `{"sha":"%v"}`, sha)
 	})
 	ctx := t.Context()
@@ -340,9 +311,6 @@ Commit Message.`
 	opts := CreateCommitOptions{Signer: mockSigner(t, signature, nil, wantMessage)}
 	commit, _, err := client.Git.CreateCommit(ctx, "o", "r", input, &opts)
 	assertNilError(t, err)
-	if cmp.Diff(gotBody, wantBody) != "" {
-		t.Errorf("Request body = %+v, want %+v\n%v", gotBody, wantBody, cmp.Diff(gotBody, wantBody))
-	}
 	if cmp.Diff(commit, wantCommit) != "" {
 		t.Errorf("Git.CreateCommit returned %+v, want %+v\n%v", commit, wantCommit, cmp.Diff(commit, wantCommit))
 	}
diff --git a/github/git_refs_test.go b/github/git_refs_test.go
index 93be53c7b2c..630e790fe8c 100644
--- a/github/git_refs_test.go
+++ b/github/git_refs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"strings"
@@ -339,19 +338,10 @@ func TestGitService_CreateRef(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	args := CreateRef{
-		Ref: "refs/heads/b",
-		SHA: "aa218f56b14c9653891f9e74264a383fa43fefbd",
-	}
-
 	mux.HandleFunc("/repos/o/r/git/refs", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateRef
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(*v, args) {
-			t.Errorf("Request body = %+v, want %+v", *v, args)
-		}
+		testJSONBody(t, r, `{"ref":"refs/heads/b","sha":"aa218f56b14c9653891f9e74264a383fa43fefbd"}`)
+
 		fmt.Fprint(w, `
 		  {
 		    "ref": "refs/heads/b",
@@ -424,19 +414,10 @@ func TestGitService_UpdateRef(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	args := UpdateRef{
-		SHA:   "aa218f56b14c9653891f9e74264a383fa43fefbd",
-		Force: Ptr(true),
-	}
-
 	mux.HandleFunc("/repos/o/r/git/refs/heads/b", func(w http.ResponseWriter, r *http.Request) {
-		var v *UpdateRef
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(*v, args) {
-			t.Errorf("Request body = %+v, want %+v", *v, args)
-		}
+		testJSONBody(t, r, `{"sha":"aa218f56b14c9653891f9e74264a383fa43fefbd","force":true}`)
+
 		fmt.Fprint(w, `
 		  {
 		    "ref": "refs/heads/b",
@@ -585,19 +566,10 @@ func TestGitService_UpdateRef_pathEscape(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	args := UpdateRef{
-		SHA:   "aa218f56b14c9653891f9e74264a383fa43fefbd",
-		Force: Ptr(true),
-	}
-
 	mux.HandleFunc("/repos/o/r/git/refs/heads/b#1", func(w http.ResponseWriter, r *http.Request) {
-		var v *UpdateRef
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(*v, args) {
-			t.Errorf("Request body = %+v, want %+v", *v, args)
-		}
+		testJSONBody(t, r, `{"sha":"aa218f56b14c9653891f9e74264a383fa43fefbd","force":true}`)
+
 		fmt.Fprint(w, `
 		  {
 		    "ref": "refs/heads/b#1",
diff --git a/github/git_tags_test.go b/github/git_tags_test.go
index 8cd1bae1b27..5882099d93a 100644
--- a/github/git_tags_test.go
+++ b/github/git_tags_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -61,13 +60,8 @@ func TestGitService_CreateTag(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/tags", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateTag
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(*v, inputTag) {
-			t.Errorf("Request body = %+v, want %+v", *v, inputTag)
-		}
+		testJSONBody(t, r, `{"tag":"t","message":"test message","object":"s","type":"commit"}`)
 
 		fmt.Fprint(w, `{"tag": "t"}`)
 	})
diff --git a/github/git_trees_test.go b/github/git_trees_test.go
index 037a30895cd..b4bc2aa180a 100644
--- a/github/git_trees_test.go
+++ b/github/git_trees_test.go
@@ -6,9 +6,7 @@
 package github
 
 import (
-	"bytes"
 	"fmt"
-	"io"
 	"net/http"
 	"testing"
 
@@ -106,17 +104,8 @@ func TestGitService_CreateTree(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/trees", func(w http.ResponseWriter, r *http.Request) {
-		got, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Fatalf("unable to read body: %v", err)
-		}
-
 		testMethod(t, r, "POST")
-
-		want := []byte(`{"base_tree":"b","tree":[{"sha":"7c258a9869f33c1e1e1f74fbb32f07c86cb5a75b","path":"file.rb","mode":"100644","type":"blob"}]}` + "\n")
-		if !bytes.Equal(got, want) {
-			t.Errorf("Git.CreateTree request body: %v, want %v", got, want)
-		}
+		testJSONBody(t, r, `{"base_tree":"b","tree":[{"sha":"7c258a9869f33c1e1e1f74fbb32f07c86cb5a75b","path":"file.rb","mode":"100644","type":"blob"}]}`)
 
 		fmt.Fprint(w, `{
 		  "sha": "cd8274d15fa3ae2ab983129fb037999f264ba9a7",
@@ -184,17 +173,9 @@ func TestGitService_CreateTree_Content(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/trees", func(w http.ResponseWriter, r *http.Request) {
-		got, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Fatalf("unable to read body: %v", err)
-		}
-
 		testMethod(t, r, "POST")
 
-		want := []byte(`{"base_tree":"b","tree":[{"path":"content.md","mode":"100644","content":"file content"}]}` + "\n")
-		if !bytes.Equal(got, want) {
-			t.Errorf("Git.CreateTree request body: %v, want %v", got, want)
-		}
+		testJSONBody(t, r, `{"base_tree":"b","tree":[{"path":"content.md","mode":"100644","content":"file content"}]}`)
 
 		fmt.Fprint(w, `{
 		  "sha": "5c6780ad2c68743383b740fd1dab6f6a33202b11",
@@ -264,17 +245,9 @@ func TestGitService_CreateTree_Delete(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/git/trees", func(w http.ResponseWriter, r *http.Request) {
-		got, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Fatalf("unable to read body: %v", err)
-		}
-
 		testMethod(t, r, "POST")
 
-		want := []byte(`{"base_tree":"b","tree":[{"sha":null,"path":"content.md","mode":"100644"}]}` + "\n")
-		if !bytes.Equal(got, want) {
-			t.Errorf("Git.CreateTree request body: %v, want %v", got, want)
-		}
+		testJSONBody(t, r, `{"base_tree":"b","tree":[{"sha":null,"path":"content.md","mode":"100644"}]}`)
 
 		fmt.Fprint(w, `{
 		  "sha": "5c6780ad2c68743383b740fd1dab6f6a33202b11",
diff --git a/github/github_test.go b/github/github_test.go
index cecc72b6ed4..14be52596f8 100644
--- a/github/github_test.go
+++ b/github/github_test.go
@@ -189,7 +189,8 @@ func testURLParseError(t *testing.T, err error) {
 	}
 }
 
-func testBody(t *testing.T, r *http.Request, want string) {
+// testPlainBody checks that the request body matches the expected string exactly.
+func testPlainBody(t *testing.T, r *http.Request, want string) {
 	t.Helper()
 	b, err := io.ReadAll(r.Body)
 	if err != nil {
@@ -200,6 +201,30 @@ func testBody(t *testing.T, r *http.Request, want string) {
 	}
 }
 
+// testJSONBody checks that the request body matches the expected JSON string, ignoring
+// differences in formatting, key ordering, and numeric types.
+func testJSONBody(t *testing.T, r *http.Request, want string) {
+	t.Helper()
+	b, err := io.ReadAll(r.Body)
+	if err != nil {
+		t.Errorf("Error reading request body: %v", err)
+	}
+
+	var gotAny any
+	if err := json.Unmarshal(b, &gotAny); err != nil {
+		t.Fatalf("request body is not valid JSON %q: %v", b, err)
+	}
+
+	var wantAny any
+	if err := json.Unmarshal([]byte(want), &wantAny); err != nil {
+		t.Fatalf("expected body is not valid JSON %q: %v", want, err)
+	}
+
+	if diff := cmp.Diff(wantAny, gotAny); diff != "" {
+		t.Errorf("request body mismatch (-want +got):\n%v", diff)
+	}
+}
+
 // testJSONMarshal tests both JSON marshaling and unmarshaling of a value by comparing
 // the marshaled output with the expected JSON string.
 //
diff --git a/github/interactions_orgs_test.go b/github/interactions_orgs_test.go
index 973fdbcf31e..031748ad050 100644
--- a/github/interactions_orgs_test.go
+++ b/github/interactions_orgs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -57,14 +56,10 @@ func TestInteractionsService_UpdateRestrictionsForOrg(t *testing.T) {
 	input := &InteractionRestriction{Limit: Ptr("existing_users")}
 
 	mux.HandleFunc("/orgs/o/interaction-limits", func(w http.ResponseWriter, r *http.Request) {
-		var v *InteractionRestriction
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeInteractionRestrictionsPreview)
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"limit":"existing_users"}`)
+
 		fmt.Fprint(w, `{"origin":"organization"}`)
 	})
 
diff --git a/github/interactions_repos_test.go b/github/interactions_repos_test.go
index 84ba45dffcb..06ed3a5e971 100644
--- a/github/interactions_repos_test.go
+++ b/github/interactions_repos_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -57,14 +56,10 @@ func TestInteractionsService_UpdateRestrictionsForRepo(t *testing.T) {
 	input := &InteractionRestriction{Limit: Ptr("existing_users")}
 
 	mux.HandleFunc("/repos/o/r/interaction-limits", func(w http.ResponseWriter, r *http.Request) {
-		var v *InteractionRestriction
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeInteractionRestrictionsPreview)
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"limit":"existing_users"}`)
+
 		fmt.Fprint(w, `{"origin":"repository"}`)
 	})
 
diff --git a/github/issue_import_test.go b/github/issue_import_test.go
index 4c744a87794..9ba1253ad87 100644
--- a/github/issue_import_test.go
+++ b/github/issue_import_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
@@ -37,13 +36,9 @@ func TestIssueImportService_Create(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/import/issues", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueImportRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeIssueImportAPI)
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"issue":{"title":"Dummy Issue","body":"Dummy description","created_at":"2020-08-11T15:30:00Z","assignee":"developer","milestone":1,"labels":["l1","l2"]},"comments":[{"created_at":"2020-08-11T15:30:00Z","body":"Comment body"}]}`)
 
 		assertWrite(t, w, issueImportResponseJSON)
 	})
@@ -95,13 +90,9 @@ func TestIssueImportService_Create_deferred(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/import/issues", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueImportRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeIssueImportAPI)
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"issue":{"title":"Dummy Issue","body":"Dummy description","created_at":"2020-08-11T15:30:00Z","assignee":"developer","milestone":1,"labels":["l1","l2"]},"comments":[{"created_at":"2020-08-11T15:30:00Z","body":"Comment body"}]}`)
 
 		w.WriteHeader(http.StatusAccepted)
 		assertWrite(t, w, issueImportResponseJSON)
@@ -141,13 +132,9 @@ func TestIssueImportService_Create_badResponse(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/import/issues", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueImportRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeIssueImportAPI)
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"issue":{"title":"Dummy Issue","body":"Dummy description","created_at":"2020-08-11T15:30:00Z","assignee":"developer","milestone":1,"labels":["l1","l2"]},"comments":[{"created_at":"2020-08-11T15:30:00Z","body":"Comment body"}]}`)
 
 		w.WriteHeader(http.StatusAccepted)
 		assertWrite(t, w, []byte("{[}"))
diff --git a/github/issues_assignees_test.go b/github/issues_assignees_test.go
index 368f690ac49..03eba65537f 100644
--- a/github/issues_assignees_test.go
+++ b/github/issues_assignees_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -172,16 +171,9 @@ func TestIssuesService_AddAssignees(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	mux.HandleFunc("/repos/o/r/issues/1/assignees", func(w http.ResponseWriter, r *http.Request) {
-		var assignees struct {
-			Assignees []string `json:"assignees,omitempty"`
-		}
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&assignees))
-
 		testMethod(t, r, "POST")
-		want := []string{"user1", "user2"}
-		if !cmp.Equal(assignees.Assignees, want) {
-			t.Errorf("assignees = %+v, want %+v", assignees, want)
-		}
+		testJSONBody(t, r, `{"assignees":["user1","user2"]}`)
+
 		fmt.Fprint(w, `{"number":1,"assignees":[{"login":"user1"},{"login":"user2"}]}`)
 	})
 
@@ -216,16 +208,9 @@ func TestIssuesService_RemoveAssignees(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	mux.HandleFunc("/repos/o/r/issues/1/assignees", func(w http.ResponseWriter, r *http.Request) {
-		var assignees struct {
-			Assignees []string `json:"assignees,omitempty"`
-		}
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&assignees))
-
 		testMethod(t, r, "DELETE")
-		want := []string{"user1", "user2"}
-		if !cmp.Equal(assignees.Assignees, want) {
-			t.Errorf("assignees = %+v, want %+v", assignees, want)
-		}
+		testJSONBody(t, r, `{"assignees":["user1","user2"]}`)
+
 		fmt.Fprint(w, `{"number":1,"assignees":[]}`)
 	})
 
diff --git a/github/issues_comments_test.go b/github/issues_comments_test.go
index befc7fc2f11..085e2e7fd29 100644
--- a/github/issues_comments_test.go
+++ b/github/issues_comments_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -161,13 +160,8 @@ func TestIssuesService_CreateComment(t *testing.T) {
 	input := &IssueComment{Body: Ptr("b")}
 
 	mux.HandleFunc("/repos/o/r/issues/1/comments", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -214,13 +208,8 @@ func TestIssuesService_EditComment(t *testing.T) {
 	input := &IssueComment{Body: Ptr("b")}
 
 	mux.HandleFunc("/repos/o/r/issues/comments/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/issues_labels_test.go b/github/issues_labels_test.go
index 37f583436fe..1b29ddf517d 100644
--- a/github/issues_labels_test.go
+++ b/github/issues_labels_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -111,13 +110,8 @@ func TestIssuesService_CreateLabel(t *testing.T) {
 	input := &Label{Name: Ptr("n")}
 
 	mux.HandleFunc("/repos/o/r/labels", func(w http.ResponseWriter, r *http.Request) {
-		var v *Label
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
 
 		fmt.Fprint(w, `{"url":"u"}`)
 	})
@@ -164,13 +158,8 @@ func TestIssuesService_EditLabel(t *testing.T) {
 	input := &Label{Name: Ptr("z")}
 
 	mux.HandleFunc("/repos/o/r/labels/n", func(w http.ResponseWriter, r *http.Request) {
-		var v *Label
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"z"}`)
 
 		fmt.Fprint(w, `{"url":"u"}`)
 	})
@@ -300,13 +289,8 @@ func TestIssuesService_AddLabelsToIssue(t *testing.T) {
 	input := []string{"a", "b"}
 
 	mux.HandleFunc("/repos/o/r/issues/1/labels", func(w http.ResponseWriter, r *http.Request) {
-		var v []string
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `["a","b"]`)
 
 		fmt.Fprint(w, `[{"url":"u"}]`)
 	})
@@ -387,13 +371,8 @@ func TestIssuesService_ReplaceLabelsForIssue(t *testing.T) {
 	input := []string{"a", "b"}
 
 	mux.HandleFunc("/repos/o/r/issues/1/labels", func(w http.ResponseWriter, r *http.Request) {
-		var v []string
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `["a","b"]`)
 
 		fmt.Fprint(w, `[{"url":"u"}]`)
 	})
diff --git a/github/issues_milestones_test.go b/github/issues_milestones_test.go
index 2ff7adbb35e..d3e5110cfc3 100644
--- a/github/issues_milestones_test.go
+++ b/github/issues_milestones_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -116,13 +115,8 @@ func TestIssuesService_CreateMilestone(t *testing.T) {
 	input := &Milestone{Title: Ptr("t")}
 
 	mux.HandleFunc("/repos/o/r/milestones", func(w http.ResponseWriter, r *http.Request) {
-		var v *Milestone
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"title":"t"}`)
 
 		fmt.Fprint(w, `{"number":1}`)
 	})
@@ -169,13 +163,8 @@ func TestIssuesService_EditMilestone(t *testing.T) {
 	input := &Milestone{Title: Ptr("t")}
 
 	mux.HandleFunc("/repos/o/r/milestones/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *Milestone
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"title":"t"}`)
 
 		fmt.Fprint(w, `{"number":1}`)
 	})
diff --git a/github/issues_test.go b/github/issues_test.go
index 00052fc7ba1..3349495b797 100644
--- a/github/issues_test.go
+++ b/github/issues_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -307,13 +306,8 @@ func TestIssuesService_Create(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/issues", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"title":"t","body":"b","labels":["l1","l2"],"assignee":"a"}`)
 
 		fmt.Fprint(w, `{"number":1}`)
 	})
@@ -360,13 +354,8 @@ func TestIssuesService_Edit(t *testing.T) {
 	input := &IssueRequest{Title: Ptr("t"), Type: Ptr("bug")}
 
 	mux.HandleFunc("/repos/o/r/issues/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *IssueRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"title":"t","type":"bug"}`)
 
 		fmt.Fprint(w, `{"number":1, "type": {"name": "bug"}}`)
 	})
diff --git a/github/markdown_test.go b/github/markdown_test.go
index 4b3be86599a..f4e7944c8d1 100644
--- a/github/markdown_test.go
+++ b/github/markdown_test.go
@@ -6,31 +6,19 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
-
-	"github.com/google/go-cmp/cmp"
 )
 
 func TestMarkdownService_Markdown(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &markdownRenderRequest{
-		Text:    Ptr("# text #"),
-		Mode:    Ptr("gfm"),
-		Context: Ptr("google/go-github"),
-	}
 	mux.HandleFunc("/markdown", func(w http.ResponseWriter, r *http.Request) {
-		var v *markdownRenderRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"text":"# text #","mode":"gfm","context":"google/go-github"}`)
+
 		fmt.Fprint(w, `<h1>text</h1>`)
 	})
 
diff --git a/github/migrations_source_import_test.go b/github/migrations_source_import_test.go
index b5b7270c238..5ff354bb32b 100644
--- a/github/migrations_source_import_test.go
+++ b/github/migrations_source_import_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -26,13 +25,8 @@ func TestMigrationService_StartImport(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/import", func(w http.ResponseWriter, r *http.Request) {
-		var v *Import
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"vcs_url":"url","vcs":"git","vcs_username":"u","vcs_password":"p"}`)
 
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{"status":"importing"}`)
@@ -109,13 +103,8 @@ func TestMigrationService_UpdateImport(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/import", func(w http.ResponseWriter, r *http.Request) {
-		var v *Import
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"vcs_url":"url","vcs":"git","vcs_username":"u","vcs_password":"p"}`)
 
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{"status":"importing"}`)
@@ -190,13 +179,8 @@ func TestMigrationService_MapCommitAuthor(t *testing.T) {
 	input := &SourceImportAuthor{Name: Ptr("n"), Email: Ptr("e")}
 
 	mux.HandleFunc("/repos/o/r/import/authors/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *SourceImportAuthor
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"email":"e","name":"n"}`)
 
 		fmt.Fprint(w, `{"id": 1}`)
 	})
@@ -233,13 +217,8 @@ func TestMigrationService_SetLFSPreference(t *testing.T) {
 	input := &Import{UseLFS: Ptr("opt_in")}
 
 	mux.HandleFunc("/repos/o/r/import/lfs", func(w http.ResponseWriter, r *http.Request) {
-		var v *Import
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"use_lfs":"opt_in"}`)
 
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{"status":"importing"}`)
diff --git a/github/orgs_actions_allowed_test.go b/github/orgs_actions_allowed_test.go
index 7996b11afa2..960a2aece22 100644
--- a/github/orgs_actions_allowed_test.go
+++ b/github/orgs_actions_allowed_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestOrganizationsService_UpdateActionsAllowed(t *testing.T) {
 	input := &ActionsAllowed{GithubOwnedAllowed: Ptr(true), VerifiedAllowed: Ptr(false), PatternsAllowed: []string{"a/b"}}
 
 	mux.HandleFunc("/orgs/o/actions/permissions/selected-actions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsAllowed
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"github_owned_allowed":true,"verified_allowed":false,"patterns_allowed":["a/b"]}`)
 
 		fmt.Fprint(w, `{"github_owned_allowed":true, "verified_allowed":false, "patterns_allowed":["a/b"]}`)
 	})
diff --git a/github/orgs_actions_permissions_test.go b/github/orgs_actions_permissions_test.go
index d01adc75ac1..f35be8e9a4e 100644
--- a/github/orgs_actions_permissions_test.go
+++ b/github/orgs_actions_permissions_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestOrganizationsService_UpdateActionsPermissions(t *testing.T) {
 	input := &ActionsPermissions{EnabledRepositories: Ptr("all"), AllowedActions: Ptr("selected")}
 
 	mux.HandleFunc("/orgs/o/actions/permissions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsPermissions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled_repositories":"all","allowed_actions":"selected"}`)
 
 		fmt.Fprint(w, `{"enabled_repositories": "all", "allowed_actions": "selected"}`)
 	})
diff --git a/github/orgs_codesecurity_configurations_test.go b/github/orgs_codesecurity_configurations_test.go
index bfd7c833d87..908b75ef843 100644
--- a/github/orgs_codesecurity_configurations_test.go
+++ b/github/orgs_codesecurity_configurations_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -116,12 +115,7 @@ func TestOrganizationsService_CreateCodeSecurityConfiguration(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/code-security/configurations", func(w http.ResponseWriter, r *http.Request) {
-		var v CodeSecurityConfiguration
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, input) {
-			t.Errorf("Organizations.CreateCodeSecurityConfiguration request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"config1","description":"desc1","code_scanning_default_setup":"enabled"}`)
 
 		fmt.Fprint(w, `{
 			"id":1,
@@ -183,12 +177,7 @@ func TestOrganizationsService_CreateCodeSecurityConfigurationWithDelegatedBypass
 	}
 
 	mux.HandleFunc("/orgs/o/code-security/configurations", func(w http.ResponseWriter, r *http.Request) {
-		var v CodeSecurityConfiguration
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, input) {
-			t.Errorf("Organizations.CreateCodeSecurityConfiguration with Bypass request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"config1","description":"desc1","secret_scanning":"enabled","secret_scanning_push_protection":"enabled","secret_scanning_delegated_bypass":"enabled","secret_scanning_delegated_bypass_options":{"reviewers":[{"reviewer_id":456,"reviewer_type":"TEAM"},{"reviewer_id":789,"reviewer_type":"ROLE"}]},"secret_protection":"enabled"}`)
 
 		fmt.Fprint(w, `{
 			"id":123,
@@ -202,15 +191,15 @@ func TestOrganizationsService_CreateCodeSecurityConfigurationWithDelegatedBypass
 				"reviewers": [
 					{
 						"security_configuration_id": 123,
-						"reviewer_type": "TEAM",	
+						"reviewer_type": "TEAM",
 						"reviewer_id": 456
 					},
 					{
 						"security_configuration_id": 123,
-						"reviewer_type": "ROLE",	
+						"reviewer_type": "ROLE",
 						"reviewer_id": 789
 					}
-				]			
+				]
 			}
 		}`)
 	})
@@ -363,12 +352,7 @@ func TestOrganizationsService_UpdateCodeSecurityConfiguration(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/code-security/configurations/1", func(w http.ResponseWriter, r *http.Request) {
-		var v CodeSecurityConfiguration
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		if !cmp.Equal(v, input) {
-			t.Errorf("Organizations.UpdateCodeSecurityConfiguration request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"config1","description":"desc1","code_scanning_default_setup":"enabled"}`)
 
 		fmt.Fprint(w, `{
 			"id":1,
@@ -442,18 +426,8 @@ func TestOrganizationsService_AttachCodeSecurityConfigurationToRepositories(t *t
 
 	mux.HandleFunc("/orgs/o/code-security/configurations/1/attach", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		type request struct {
-			Scope                 string  `json:"scope"`
-			SelectedRepositoryIDs []int64 `json:"selected_repository_ids,omitempty"`
-		}
-		var v *request
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-		if v.Scope != "selected" {
-			t.Errorf("Organizations.AttachCodeSecurityConfigurationToRepositories request body scope = %v, want selected", v.Scope)
-		}
-		if !cmp.Equal(v.SelectedRepositoryIDs, []int64{5, 20}) {
-			t.Errorf("Organizations.AttachCodeSecurityConfigurationToRepositories request body selected_repository_ids = %+v, want %+v", v.SelectedRepositoryIDs, []int64{5, 20})
-		}
+		testJSONBody(t, r, `{"scope":"selected","selected_repository_ids":[5,20]}`)
+
 		w.WriteHeader(http.StatusAccepted)
 	})
 
diff --git a/github/orgs_hooks_configuration_test.go b/github/orgs_hooks_configuration_test.go
index 7b154bbbbdf..80b14fc0903 100644
--- a/github/orgs_hooks_configuration_test.go
+++ b/github/orgs_hooks_configuration_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -67,16 +66,13 @@ func TestOrganizationsService_EditHookConfiguration(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &HookConfig{}
+	input := &HookConfig{
+		ContentType: Ptr("json"),
+	}
 
 	mux.HandleFunc("/orgs/o/hooks/1/config", func(w http.ResponseWriter, r *http.Request) {
-		var v *HookConfig
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"content_type":"json"}`)
 
 		fmt.Fprint(w, `{"content_type": "json", "insecure_ssl": "0", "secret": "********", "url": "https://example.com/webhook"}`)
 	})
diff --git a/github/orgs_hooks_test.go b/github/orgs_hooks_test.go
index a0941aade8f..19beada4d05 100644
--- a/github/orgs_hooks_test.go
+++ b/github/orgs_hooks_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -68,14 +67,8 @@ func TestOrganizationsService_CreateHook(t *testing.T) {
 	input := &Hook{CreatedAt: &Timestamp{referenceTime}}
 
 	mux.HandleFunc("/orgs/o/hooks", func(w http.ResponseWriter, r *http.Request) {
-		var v *createHookRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &createHookRequest{Name: "web"}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"web"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -158,16 +151,13 @@ func TestOrganizationsService_EditHook(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &Hook{}
+	input := &Hook{
+		Name: Ptr("web"),
+	}
 
 	mux.HandleFunc("/orgs/o/hooks/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *Hook
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"web"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/orgs_immutable_releases_test.go b/github/orgs_immutable_releases_test.go
index 92879ae0aaf..48f1f5c246f 100644
--- a/github/orgs_immutable_releases_test.go
+++ b/github/orgs_immutable_releases_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -68,17 +67,7 @@ func TestOrganizationsService_UpdateImmutableReleasesSettings(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/settings/immutable-releases", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-
-		var gotBody map[string]any
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&gotBody))
-
-		wantBody := map[string]any{
-			"enforced_repositories": "selected",
-		}
-
-		if !cmp.Equal(gotBody, wantBody) {
-			t.Errorf("Request body = %+v, want %+v", gotBody, wantBody)
-		}
+		testJSONBody(t, r, `{"enforced_repositories":"selected"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 		fmt.Fprint(w, `{"enforced_repositories":"selected"}`)
@@ -166,15 +155,7 @@ func TestOrganizationsService_SetImmutableReleaseRepositories(t *testing.T) {
 	input := []int64{1, 2, 3}
 	mux.HandleFunc("/orgs/o/settings/immutable-releases/repositories", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-
-		var gotBody setImmutableReleasesRepositoriesOptions
-		if err := json.NewDecoder(r.Body).Decode(&gotBody); err != nil {
-			t.Fatalf("Failed to decode request body: %v", err)
-		}
-
-		if !cmp.Equal(gotBody.SelectedRepositoryIDs, input) {
-			t.Errorf("Request body = %+v, want %+v", gotBody.SelectedRepositoryIDs, input)
-		}
+		testJSONBody(t, r, `{"selected_repository_ids":[1,2,3]}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/orgs_issue_types_test.go b/github/orgs_issue_types_test.go
index 30c9b4a2efa..9e6fde10de7 100644
--- a/github/orgs_issue_types_test.go
+++ b/github/orgs_issue_types_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -97,13 +96,8 @@ func TestOrganizationsService_CreateIssueType(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/issue-types", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateOrUpdateIssueTypesOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"Epic","is_enabled":true,"is_private":true,"description":"An issue type for a multi-week tracking of work","color":"green"}`)
 
 		fmt.Fprint(w, `{
 				"id": 410,
@@ -161,13 +155,8 @@ func TestOrganizationsService_UpdateIssueType(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/issue-types/410", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateOrUpdateIssueTypesOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"Epic","is_enabled":true,"is_private":true,"description":"An issue type for a multi-week tracking of work","color":"green"}`)
 
 		fmt.Fprint(w, `{
 				"id": 410,
diff --git a/github/orgs_members_test.go b/github/orgs_members_test.go
index 1738f401351..4d1e2e29735 100644
--- a/github/orgs_members_test.go
+++ b/github/orgs_members_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -469,13 +468,8 @@ func TestOrganizationsService_EditOrgMembership_AuthenticatedUser(t *testing.T)
 	input := &Membership{State: Ptr("active")}
 
 	mux.HandleFunc("/user/memberships/orgs/o", func(w http.ResponseWriter, r *http.Request) {
-		var v *Membership
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"state":"active"}`)
 
 		fmt.Fprint(w, `{"url":"u"}`)
 	})
@@ -513,13 +507,8 @@ func TestOrganizationsService_EditOrgMembership_SpecifiedUser(t *testing.T) {
 	input := &Membership{State: Ptr("active")}
 
 	mux.HandleFunc("/orgs/o/memberships/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *Membership
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"state":"active"}`)
 
 		fmt.Fprint(w, `{"url":"u"}`)
 	})
@@ -673,13 +662,8 @@ func TestOrganizationsService_CreateOrgInvitation(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/invitations", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateOrgInvitationOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"email":"octocat@github.com","role":"direct_member","team_ids":[12,26]}`)
 
 		fmt.Fprintln(w, `{"email": "octocat@github.com"}`)
 	})
diff --git a/github/orgs_personal_access_tokens_test.go b/github/orgs_personal_access_tokens_test.go
index 868132c7e92..dba83415d03 100644
--- a/github/orgs_personal_access_tokens_test.go
+++ b/github/orgs_personal_access_tokens_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -344,13 +343,8 @@ func TestOrganizationsService_ReviewPersonalAccessTokenRequest(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/personal-access-token-requests/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *ReviewPersonalAccessTokenRequestOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"action":"a","reason":"r"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/orgs_properties_test.go b/github/orgs_properties_test.go
index 9d76ea8714e..c5577cf97d3 100644
--- a/github/orgs_properties_test.go
+++ b/github/orgs_properties_test.go
@@ -132,7 +132,7 @@ func TestOrganizationsService_CreateOrUpdateCustomProperties(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/properties/schema", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"properties":[{"property_name":"name","value_type":"single_select","required":true},{"property_name":"service","value_type":"string"}]}`+"\n")
+		testJSONBody(t, r, `{"properties":[{"property_name":"name","value_type":"single_select","required":true},{"property_name":"service","value_type":"string"}]}`)
 		fmt.Fprint(w, `[
 		{
           "property_name": "name",
@@ -491,7 +491,7 @@ func TestOrganizationsService_CreateOrUpdateRepoCustomPropertyValues(t *testing.
 
 	mux.HandleFunc("/orgs/o/properties/values", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		testBody(t, r, `{"repository_names":["repo"],"properties":[{"property_name":"service","value":"string"}]}`+"\n")
+		testJSONBody(t, r, `{"repository_names":["repo"],"properties":[{"property_name":"service","value":"string"}]}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/orgs_rules_test.go b/github/orgs_rules_test.go
index 1c70947931e..5202a2a5774 100644
--- a/github/orgs_rules_test.go
+++ b/github/orgs_rules_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -1594,15 +1593,7 @@ func TestOrganizationsService_UpdateRepositoryRuleset_OmitZero_Nil(t *testing.T)
 
 	mux.HandleFunc("/orgs/o/rulesets/21", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-
-		var v map[string]any
-		if err := json.NewDecoder(r.Body).Decode(&v); err != nil {
-			t.Errorf("could not decode body: %v", err)
-		}
-
-		if _, ok := v["bypass_actors"]; ok {
-			t.Error("Request body contained 'bypass_actors', expected it to be omitted for nil input")
-		}
+		testJSONBody(t, r, `{"name":"test ruleset","source":"","enforcement":"active"}`)
 
 		fmt.Fprint(w, `{
 			"id": 21,
@@ -1633,7 +1624,7 @@ func TestOrganizationsService_UpdateRepositoryRuleset_OmitZero_EmptySlice(t *tes
 	mux.HandleFunc("/orgs/o/rulesets/21", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 
-		testBody(t, r, `{"name":"test ruleset","source":"","enforcement":"active","bypass_actors":[]}`+"\n")
+		testJSONBody(t, r, `{"name":"test ruleset","source":"","enforcement":"active","bypass_actors":[]}`)
 
 		fmt.Fprint(w, `{
 			"id": 21,
diff --git a/github/orgs_test.go b/github/orgs_test.go
index 15b7414cc36..e39f36acd53 100644
--- a/github/orgs_test.go
+++ b/github/orgs_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -267,14 +266,9 @@ func TestOrganizationsService_Edit(t *testing.T) {
 	input := &Organization{Login: Ptr("l")}
 
 	mux.HandleFunc("/orgs/o", func(w http.ResponseWriter, r *http.Request) {
-		var v *Organization
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testHeader(t, r, "Accept", mediaTypeMemberAllowedRepoCreationTypePreview)
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"login":"l"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/private_registries_test.go b/github/private_registries_test.go
index 85b50b2801f..0e9ba3c5da0 100644
--- a/github/private_registries_test.go
+++ b/github/private_registries_test.go
@@ -101,14 +101,9 @@ func TestPrivateRegistriesService_CreateOrganizationPrivateRegistry(t *testing.T
 	}
 
 	mux.HandleFunc("/orgs/o/private-registries", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateOrganizationPrivateRegistry
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "X-Github-Api-Version", "2026-03-10")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"registry_type":"maven_repository","url":"https://example.com/OWNER/REPOSITORY","username":"monalisa","encrypted_value":"encrypted_value","key_id":"key_id","visibility":"selected","selected_repository_ids":[1,2,3]}`)
 
 		w.WriteHeader(http.StatusCreated)
 		fmt.Fprint(w, `{
@@ -399,14 +394,9 @@ func TestPrivateRegistries_UpdateOrganizationPrivateRegistry(t *testing.T) {
 	}
 
 	mux.HandleFunc("/orgs/o/private-registries/MAVEN_REPOSITORY_SECRET", func(w http.ResponseWriter, r *http.Request) {
-		var v *UpdateOrganizationPrivateRegistry
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "X-Github-Api-Version", "2026-03-10")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"username":"monalisa","encrypted_value":"encrypted_value","key_id":"key_id","visibility":"selected"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/projects_test.go b/github/projects_test.go
index 746d95fbafa..24bc64b8501 100644
--- a/github/projects_test.go
+++ b/github/projects_test.go
@@ -9,7 +9,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io"
 	"net/http"
 	"testing"
 )
@@ -801,11 +800,8 @@ func TestProjectsService_AddOrganizationProjectItem(t *testing.T) {
 
 	mux.HandleFunc("/orgs/o/projectsV2/1/items", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		if body != `{"type":"Issue","id":99}`+"\n" { // encoder adds newline
-			t.Fatalf("unexpected body: %s", body)
-		}
+		testJSONBody(t, r, `{"type":"Issue","id":99}`)
+
 		fmt.Fprint(w, `{"id":99,"node_id":"PVTI_new"}`)
 	})
 
@@ -921,11 +917,8 @@ func TestProjectsService_UpdateOrganizationProjectItem(t *testing.T) {
 	client, mux, _ := setup(t)
 	mux.HandleFunc("/orgs/o/projectsV2/1/items/17", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		if body != `{"archived":true}`+"\n" {
-			t.Fatalf("unexpected body: %s", body)
-		}
+		testJSONBody(t, r, `{"archived":true}`)
+
 		fmt.Fprint(w, `{"id":17}`)
 	})
 	archived := true
@@ -963,13 +956,8 @@ func TestProjectsService_UpdateOrganizationProjectItem_WithFieldUpdates(t *testi
 	client, mux, _ := setup(t)
 	mux.HandleFunc("/orgs/o/projectsV2/1/items/17", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		// Verify the field updates are properly formatted in the request body
-		expectedBody := `{"fields":[{"id":123,"value":"Updated text value"},{"id":456,"value":"Done"}]}`
-		if body != expectedBody+"\n" {
-			t.Fatalf("unexpected body: %s, expected: %s", body, expectedBody)
-		}
+		testJSONBody(t, r, `{"fields":[{"id":123,"value":"Updated text value"},{"id":456,"value":"Done"}]}`)
+
 		fmt.Fprint(w, `{"id":17,"node_id":"PVTI_node_updated"}`)
 	})
 
@@ -1074,11 +1062,8 @@ func TestProjectsService_AddUserProjectItem(t *testing.T) {
 	client, mux, _ := setup(t)
 	mux.HandleFunc("/users/u/projectsV2/2/items", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		if body != `{"type":"PullRequest","id":123}`+"\n" {
-			t.Fatalf("unexpected body: %s", body)
-		}
+		testJSONBody(t, r, `{"type":"PullRequest","id":123}`)
+
 		fmt.Fprint(w, `{"id":123,"node_id":"PVTI_new_user"}`)
 	})
 	ctx := t.Context()
@@ -1192,11 +1177,8 @@ func TestProjectsService_UpdateUserProjectItem(t *testing.T) {
 	client, mux, _ := setup(t)
 	mux.HandleFunc("/users/u/projectsV2/2/items/55", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		if body != `{"archived":false}`+"\n" {
-			t.Fatalf("unexpected body: %s", body)
-		}
+		testJSONBody(t, r, `{"archived":false}`)
+
 		fmt.Fprint(w, `{"id":55}`)
 	})
 	archived := false
@@ -1234,13 +1216,8 @@ func TestProjectsService_UpdateUserProjectItem_WithFieldUpdates(t *testing.T) {
 	client, mux, _ := setup(t)
 	mux.HandleFunc("/users/u/projectsV2/2/items/55", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-		b, _ := io.ReadAll(r.Body)
-		body := string(b)
-		// Verify the field updates are properly formatted in the request body
-		expectedBody := `{"fields":[{"id":100,"value":"In Progress"},{"id":200,"value":5}]}`
-		if body != expectedBody+"\n" {
-			t.Fatalf("unexpected body: %s, expected: %s", body, expectedBody)
-		}
+		testJSONBody(t, r, `{"fields":[{"id":100,"value":"In Progress"},{"id":200,"value":5}]}`)
+
 		fmt.Fprint(w, `{"id":55,"node_id":"PVTI_user_updated"}`)
 	})
 
diff --git a/github/pulls_comments_test.go b/github/pulls_comments_test.go
index 0c77bb24a87..cbca538e746 100644
--- a/github/pulls_comments_test.go
+++ b/github/pulls_comments_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"strings"
@@ -268,14 +267,9 @@ func TestPullRequestsService_CreateComment(t *testing.T) {
 
 	wantAcceptHeaders := []string{mediaTypeReactionsPreview, mediaTypeMultiLineCommentsPreview}
 	mux.HandleFunc("/repos/o/r/pulls/1/comments", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -319,16 +313,9 @@ func TestPullRequestsService_CreateCommentInReplyTo(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &PullRequestComment{Body: Ptr("b")}
-
 	mux.HandleFunc("/repos/o/r/pulls/1/comments", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b","in_reply_to":2}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -366,13 +353,8 @@ func TestPullRequestsService_EditComment(t *testing.T) {
 	input := &PullRequestComment{Body: Ptr("b")}
 
 	mux.HandleFunc("/repos/o/r/pulls/comments/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/pulls_reviewers_test.go b/github/pulls_reviewers_test.go
index 7917497a75d..4ad7a2b3cc0 100644
--- a/github/pulls_reviewers_test.go
+++ b/github/pulls_reviewers_test.go
@@ -125,7 +125,7 @@ func TestRequestReviewers(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/pulls/1/requested_reviewers", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"reviewers":["octocat","googlebot"],"team_reviewers":["justice-league","injustice-league"]}`+"\n")
+		testJSONBody(t, r, `{"reviewers":["octocat","googlebot"],"team_reviewers":["justice-league","injustice-league"]}`)
 		fmt.Fprint(w, `{"number":1}`)
 	})
 
@@ -156,7 +156,7 @@ func TestRemoveReviewers(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/pulls/1/requested_reviewers", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"reviewers":["octocat","googlebot"],"team_reviewers":["justice-league"]}`+"\n")
+		testJSONBody(t, r, `{"reviewers":["octocat","googlebot"],"team_reviewers":["justice-league"]}`)
 	})
 
 	ctx := t.Context()
@@ -177,7 +177,7 @@ func TestRemoveReviewers_teamsOnly(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/pulls/1/requested_reviewers", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"reviewers":[],"team_reviewers":["justice-league"]}`+"\n")
+		testJSONBody(t, r, `{"reviewers":[],"team_reviewers":["justice-league"]}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/pulls_reviews_test.go b/github/pulls_reviews_test.go
index 02ee6084b03..cc733a31352 100644
--- a/github/pulls_reviews_test.go
+++ b/github/pulls_reviews_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
@@ -366,13 +365,8 @@ func TestPullRequestsService_CreateReview(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pulls/1/reviews", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestReviewRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"commit_id":"commit_id","body":"b","event":"APPROVE"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -470,13 +464,8 @@ func TestPullRequestsService_CreateReview_addHeader(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pulls/1/reviews", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestReviewRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"comments":[{"path":"path/to/file.go","body":"this is a comment body","side":"RIGHT","line":11},{"path":"path/to/file.go","body":"this is a comment body","side":"LEFT","line":22},{"path":"path/to/file.go","body":"this is a comment body","side":"RIGHT","line":33}]}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -534,13 +523,8 @@ func TestPullRequestsService_SubmitReview(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pulls/1/reviews/1/events", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestReviewRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b","event":"APPROVE"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -587,13 +571,8 @@ func TestPullRequestsService_DismissReview(t *testing.T) {
 	input := &PullRequestReviewDismissalRequest{Message: Ptr("m")}
 
 	mux.HandleFunc("/repos/o/r/pulls/1/reviews/1/dismissals", func(w http.ResponseWriter, r *http.Request) {
-		var v *PullRequestReviewDismissalRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"message":"m"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/pulls_test.go b/github/pulls_test.go
index b98188758ee..dd956704c57 100644
--- a/github/pulls_test.go
+++ b/github/pulls_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -359,13 +358,8 @@ func TestPullRequestsService_Create(t *testing.T) {
 	input := &NewPullRequest{Title: Ptr("t")}
 
 	mux.HandleFunc("/repos/o/r/pulls", func(w http.ResponseWriter, r *http.Request) {
-		var v *NewPullRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"title":"t"}`)
 
 		fmt.Fprint(w, `{"number":1}`)
 	})
@@ -486,7 +480,7 @@ func TestPullRequestsService_Edit(t *testing.T) {
 		madeRequest := false
 		mux.HandleFunc(fmt.Sprintf("/repos/o/r/pulls/%v", i), func(w http.ResponseWriter, r *http.Request) {
 			testMethod(t, r, "PATCH")
-			testBody(t, r, tt.wantUpdate+"\n")
+			testJSONBody(t, r, tt.wantUpdate)
 			_, err := io.WriteString(w, tt.sendResponse)
 			assertNilError(t, err)
 			madeRequest = true
@@ -804,7 +798,7 @@ func TestPullRequestsService_Merge_options(t *testing.T) {
 		madeRequest := false
 		mux.HandleFunc(fmt.Sprintf("/repos/o/r/pulls/%v/merge", i), func(_ http.ResponseWriter, r *http.Request) {
 			testMethod(t, r, "PUT")
-			testBody(t, r, test.wantBody+"\n")
+			testJSONBody(t, r, test.wantBody)
 			madeRequest = true
 		})
 		ctx := t.Context()
@@ -823,7 +817,7 @@ func TestPullRequestsService_Merge_Blank_Message(t *testing.T) {
 	expectedBody := ""
 	mux.HandleFunc("/repos/o/r/pulls/1/merge", func(_ http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-		testBody(t, r, expectedBody+"\n")
+		testJSONBody(t, r, expectedBody)
 		madeRequest = true
 	})
 
diff --git a/github/repos_actions_access_test.go b/github/repos_actions_access_test.go
index 715c091ac50..10d25c327db 100644
--- a/github/repos_actions_access_test.go
+++ b/github/repos_actions_access_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestRepositoriesService_EditActionsAccessLevel(t *testing.T) {
 	input := &RepositoryActionsAccessLevel{AccessLevel: Ptr("organization")}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/access", func(_ http.ResponseWriter, r *http.Request) {
-		var v *RepositoryActionsAccessLevel
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"access_level":"organization"}`)
 	})
 
 	ctx := t.Context()
diff --git a/github/repos_actions_allowed_test.go b/github/repos_actions_allowed_test.go
index 226ee1ee074..64e715bbb2e 100644
--- a/github/repos_actions_allowed_test.go
+++ b/github/repos_actions_allowed_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestRepositoriesService_UpdateActionsAllowed(t *testing.T) {
 	input := &ActionsAllowed{GithubOwnedAllowed: Ptr(true), VerifiedAllowed: Ptr(false), PatternsAllowed: []string{"a/b"}}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/selected-actions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsAllowed
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"github_owned_allowed":true,"verified_allowed":false,"patterns_allowed":["a/b"]}`)
 
 		fmt.Fprint(w, `{"github_owned_allowed":true, "verified_allowed":false, "patterns_allowed":["a/b"]}`)
 	})
diff --git a/github/repos_actions_permissions_test.go b/github/repos_actions_permissions_test.go
index cb39b0ed43c..492155ec35a 100644
--- a/github/repos_actions_permissions_test.go
+++ b/github/repos_actions_permissions_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -55,13 +54,8 @@ func TestRepositoriesService_UpdateActionsPermissions(t *testing.T) {
 	input := &ActionsPermissionsRepository{Enabled: Ptr(true), AllowedActions: Ptr("selected"), SHAPinningRequired: Ptr(true)}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions", func(w http.ResponseWriter, r *http.Request) {
-		var v *ActionsPermissionsRepository
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"enabled":true,"allowed_actions":"selected","sha_pinning_required":true}`)
 
 		fmt.Fprint(w, `{"enabled": true, "allowed_actions": "selected", "sha_pinning_required": true}`)
 	})
@@ -154,13 +148,8 @@ func TestRepositoriesService_UpdateDefaultWorkflowPermissions(t *testing.T) {
 	input := &DefaultWorkflowPermissionRepository{DefaultWorkflowPermissions: Ptr("read"), CanApprovePullRequestReviews: Ptr(true)}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/workflow", func(w http.ResponseWriter, r *http.Request) {
-		var v *DefaultWorkflowPermissionRepository
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"default_workflow_permissions":"read","can_approve_pull_request_reviews":true}`)
 
 		fmt.Fprint(w, `{ "default_workflow_permissions": "read", "can_approve_pull_request_reviews": true }`)
 	})
@@ -236,13 +225,9 @@ func TestRepositoriesService_UpdateArtifactAndLogRetentionPeriod(t *testing.T) {
 	input := &ArtifactPeriodOpt{Days: Ptr(90)}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/artifact-and-log-retention", func(w http.ResponseWriter, r *http.Request) {
-		var v *ArtifactPeriodOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"days":90}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -317,13 +302,9 @@ func TestRepositoriesService_UpdatePrivateRepoForkPRWorkflowSettings(t *testing.
 	}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/fork-pr-workflows-private-repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *WorkflowsPermissionsOpt
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"run_workflows_from_fork_pull_requests":true,"send_write_tokens_to_workflows":false,"send_secrets_and_variables":true}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
@@ -389,13 +370,9 @@ func TestActionsService_UpdateForkPRContributorApprovalPermissions(t *testing.T)
 	input := ContributorApprovalPermissions{ApprovalPolicy: "require_approval"}
 
 	mux.HandleFunc("/repos/o/r/actions/permissions/fork-pr-contributor-approval", func(w http.ResponseWriter, r *http.Request) {
-		var v *ContributorApprovalPermissions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, &input)
-		}
+		testJSONBody(t, r, `{"approval_policy":"require_approval"}`)
+
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/repos_autolinks_test.go b/github/repos_autolinks_test.go
index 411063fef45..73f78488161 100644
--- a/github/repos_autolinks_test.go
+++ b/github/repos_autolinks_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -63,12 +62,9 @@ func TestRepositoriesService_AddAutolink(t *testing.T) {
 		IsAlphanumeric: Ptr(true),
 	}
 	mux.HandleFunc("/repos/o/r/autolinks", func(w http.ResponseWriter, r *http.Request) {
-		var v *AutolinkOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"key_prefix":"TICKET-","url_template":"https://example.com/TICKET?query=<num>","is_alphanumeric":true}`)
+
 		w.WriteHeader(http.StatusOK)
 		assertWrite(t, w, []byte(`
 			{
diff --git a/github/repos_collaborators_test.go b/github/repos_collaborators_test.go
index 12ef0b4d635..ec32f51b168 100644
--- a/github/repos_collaborators_test.go
+++ b/github/repos_collaborators_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -266,12 +265,9 @@ func TestRepositoriesService_AddCollaborator(t *testing.T) {
 
 	opt := &RepositoryAddCollaboratorOptions{Permission: "admin"}
 	mux.HandleFunc("/repos/o/r/collaborators/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepositoryAddCollaboratorOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"permission":"admin"}`)
+
 		w.WriteHeader(http.StatusOK)
 		assertWrite(t, w, []byte(`{"permissions": "write","url": "https://api.github.com/user/repository_invitations/1296269","html_url": "https://github.com/octocat/Hello-World/invitations","id":1,"permissions":"write","repository":{"url":"s","name":"r","id":1},"invitee":{"login":"u"},"inviter":{"login":"o"}}`))
 	})
diff --git a/github/repos_comments_test.go b/github/repos_comments_test.go
index 3328b00722c..1a050b77feb 100644
--- a/github/repos_comments_test.go
+++ b/github/repos_comments_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -115,13 +114,8 @@ func TestRepositoriesService_CreateComment(t *testing.T) {
 	input := &RepositoryComment{Body: Ptr("b")}
 
 	mux.HandleFunc("/repos/o/r/commits/s/comments", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepositoryComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -213,13 +207,8 @@ func TestRepositoriesService_UpdateComment(t *testing.T) {
 	input := &RepositoryComment{Body: Ptr("b")}
 
 	mux.HandleFunc("/repos/o/r/comments/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepositoryComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"b"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/repos_deployment_protection_rules_test.go b/github/repos_deployment_protection_rules_test.go
index 0ab490665b9..c51c1df9fb0 100644
--- a/github/repos_deployment_protection_rules_test.go
+++ b/github/repos_deployment_protection_rules_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -59,14 +58,8 @@ func TestRepositoriesService_CreateCustomDeploymentProtectionRule(t *testing.T)
 	}
 
 	mux.HandleFunc("/repos/o/r/environments/e/deployment_protection_rules", func(w http.ResponseWriter, r *http.Request) {
-		var v *CustomDeploymentProtectionRuleRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := input
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"integration_id":5}`)
 
 		fmt.Fprint(w, `{"id":3, "node_id": "IEH37kRlcGxveW1lbnRTdGF0ddiv", "enabled": true, "app": {"id": 1, "node_id": "GHT58kRlcGxveW1lbnRTdTY!bbcy", "slug": "a-custom-app", "integration_url": "https://api.github.com/apps/a-custom-app"}}`)
 	})
diff --git a/github/repos_deployments_test.go b/github/repos_deployments_test.go
index b1294929350..056dfe3f8a2 100644
--- a/github/repos_deployments_test.go
+++ b/github/repos_deployments_test.go
@@ -95,15 +95,10 @@ func TestRepositoriesService_CreateDeployment(t *testing.T) {
 	input := &DeploymentRequest{Ref: Ptr("1111"), Task: Ptr("deploy"), TransientEnvironment: Ptr(true)}
 
 	mux.HandleFunc("/repos/o/r/deployments", func(w http.ResponseWriter, r *http.Request) {
-		var v *DeploymentRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		wantAcceptHeaders := []string{mediaTypeDeploymentStatusPreview, mediaTypeExpandDeploymentStatusPreview}
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"ref":"1111","task":"deploy","transient_environment":true}`)
 
 		fmt.Fprint(w, `{"ref": "1111", "task": "deploy"}`)
 	})
@@ -254,15 +249,10 @@ func TestRepositoriesService_CreateDeploymentStatus(t *testing.T) {
 	input := &DeploymentStatusRequest{State: Ptr("inactive"), Description: Ptr("deploy"), AutoInactive: Ptr(false)}
 
 	mux.HandleFunc("/repos/o/r/deployments/1/statuses", func(w http.ResponseWriter, r *http.Request) {
-		var v *DeploymentStatusRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		wantAcceptHeaders := []string{mediaTypeDeploymentStatusPreview, mediaTypeExpandDeploymentStatusPreview}
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"state":"inactive","description":"deploy","auto_inactive":false}`)
 
 		fmt.Fprint(w, `{"state": "inactive", "description": "deploy"}`)
 	})
diff --git a/github/repos_environments_test.go b/github/repos_environments_test.go
index 75642a2cc92..4c165ea42bc 100644
--- a/github/repos_environments_test.go
+++ b/github/repos_environments_test.go
@@ -185,14 +185,9 @@ func TestRepositoriesService_CreateEnvironment(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/environments/e", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateUpdateEnvironment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		want := &CreateUpdateEnvironment{WaitTimer: Ptr(30), CanAdminsBypass: Ptr(true)}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"wait_timer":30,"reviewers":null,"can_admins_bypass":true,"deployment_branch_policy":null}`)
+
 		fmt.Fprint(w, `{"id": 1, "name": "staging",	"protection_rules": [{"id": 1, "type": "wait_timer", "wait_timer": 30}]}`)
 	})
 
@@ -230,18 +225,14 @@ func TestRepositoriesService_CreateEnvironment_noEnterprise(t *testing.T) {
 	callCount := 0
 
 	mux.HandleFunc("/repos/o/r/environments/e", func(w http.ResponseWriter, r *http.Request) {
-		var v *CreateUpdateEnvironment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
+
 		if callCount == 0 {
+			testJSONBody(t, r, `{"wait_timer":0,"reviewers":null,"can_admins_bypass":true,"deployment_branch_policy":null}`)
 			w.WriteHeader(http.StatusUnprocessableEntity)
 			callCount++
 		} else {
-			want := &CreateUpdateEnvironment{}
-			if !cmp.Equal(v, want) {
-				t.Errorf("Request body = %+v, want %+v", v, want)
-			}
+			testJSONBody(t, r, `{"deployment_branch_policy":null}`)
 			fmt.Fprint(w, `{"id": 1, "name": "staging",	"protection_rules": []}`)
 		}
 	})
@@ -270,19 +261,9 @@ func TestRepositoriesService_createNewEnvNoEnterprise(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/environments/e", func(w http.ResponseWriter, r *http.Request) {
-		var v *createUpdateEnvironmentNoEnterprise
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		want := &createUpdateEnvironmentNoEnterprise{
-			DeploymentBranchPolicy: &BranchPolicy{
-				ProtectedBranches:    Ptr(true),
-				CustomBranchPolicies: Ptr(false),
-			},
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"deployment_branch_policy":{"protected_branches":true,"custom_branch_policies":false}}`)
+
 		fmt.Fprint(w, `{"id": 1, "name": "staging",	"protection_rules": [{"id": 1, "node_id": "id", "type": "branch_policy"}], "deployment_branch_policy": {"protected_branches": true, "custom_branch_policies": false}}`)
 	})
 
diff --git a/github/repos_forks_test.go b/github/repos_forks_test.go
index bf67c7dc704..44ff595f3fb 100644
--- a/github/repos_forks_test.go
+++ b/github/repos_forks_test.go
@@ -73,7 +73,7 @@ func TestRepositoriesService_CreateFork(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/forks", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"organization":"o","name":"n","default_branch_only":true}`+"\n")
+		testJSONBody(t, r, `{"organization":"o","name":"n","default_branch_only":true}`)
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
@@ -110,7 +110,7 @@ func TestRepositoriesService_CreateFork_deferred(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/forks", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"organization":"o","name":"n","default_branch_only":true}`+"\n")
+		testJSONBody(t, r, `{"organization":"o","name":"n","default_branch_only":true}`)
 		// This response indicates the fork will happen asynchronously.
 		w.WriteHeader(http.StatusAccepted)
 		fmt.Fprint(w, `{"id":1}`)
diff --git a/github/repos_hooks_configuration_test.go b/github/repos_hooks_configuration_test.go
index 620265a6d05..90ddd6f2caa 100644
--- a/github/repos_hooks_configuration_test.go
+++ b/github/repos_hooks_configuration_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -67,16 +66,13 @@ func TestRepositoriesService_EditHookConfiguration(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &HookConfig{}
+	input := &HookConfig{
+		ContentType: Ptr("xml"),
+	}
 
 	mux.HandleFunc("/repos/o/r/hooks/1/config", func(w http.ResponseWriter, r *http.Request) {
-		var v *HookConfig
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"content_type":"xml"}`)
 
 		fmt.Fprint(w, `{"content_type": "json", "insecure_ssl": "0", "secret": "********", "url": "https://example.com/webhook"}`)
 	})
diff --git a/github/repos_hooks_test.go b/github/repos_hooks_test.go
index 2e9ea17978f..6a989890c1a 100644
--- a/github/repos_hooks_test.go
+++ b/github/repos_hooks_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -21,14 +20,8 @@ func TestRepositoriesService_CreateHook(t *testing.T) {
 	input := &Hook{CreatedAt: &Timestamp{referenceTime}}
 
 	mux.HandleFunc("/repos/o/r/hooks", func(w http.ResponseWriter, r *http.Request) {
-		var v *createHookRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &createHookRequest{Name: "web"}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"web"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -168,16 +161,13 @@ func TestRepositoriesService_EditHook(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &Hook{}
+	input := &Hook{
+		Name: Ptr("web"),
+	}
 
 	mux.HandleFunc("/repos/o/r/hooks/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *Hook
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"web"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/repos_keys_test.go b/github/repos_keys_test.go
index 5f7bfd265d2..c28e0ccfbff 100644
--- a/github/repos_keys_test.go
+++ b/github/repos_keys_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -111,13 +110,8 @@ func TestRepositoriesService_CreateKey(t *testing.T) {
 	input := &Key{Key: Ptr("k"), Title: Ptr("t")}
 
 	mux.HandleFunc("/repos/o/r/keys", func(w http.ResponseWriter, r *http.Request) {
-		var v *Key
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"key":"k","title":"t"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/repos_merging_test.go b/github/repos_merging_test.go
index f54ef4d087b..607f2275971 100644
--- a/github/repos_merging_test.go
+++ b/github/repos_merging_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -25,13 +24,8 @@ func TestRepositoriesService_Merge(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/merges", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepositoryMergeRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"base":"b","head":"h","commit_message":"c"}`)
 
 		fmt.Fprint(w, `{"sha":"s"}`)
 	})
@@ -90,13 +84,8 @@ func TestRepositoriesService_MergeUpstream(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/merge-upstream", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepoMergeUpstreamRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"branch":"b"}`)
 
 		fmt.Fprint(w, `{"merge_type":"m"}`)
 	})
diff --git a/github/repos_pages_test.go b/github/repos_pages_test.go
index 0b1d9a486dd..5034baa645b 100644
--- a/github/repos_pages_test.go
+++ b/github/repos_pages_test.go
@@ -6,10 +6,7 @@
 package github
 
 import (
-	"bytes"
-	"encoding/json"
 	"fmt"
-	"io"
 	"net/http"
 	"testing"
 
@@ -30,15 +27,9 @@ func TestRepositoriesService_EnablePagesLegacy(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		var v *createPagesRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeEnablePagesAPIPreview)
-		want := &createPagesRequest{BuildType: Ptr("legacy"), Source: &PagesSource{Branch: Ptr("master"), Path: Ptr("/")}}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"build_type":"legacy","source":{"branch":"master","path":"/"}}`)
 
 		fmt.Fprint(w, `{"url":"u","status":"s","cname":"c","custom_404":false,"html_url":"h","build_type": "legacy","source": {"branch":"master", "path":"/"}}`)
 	})
@@ -84,15 +75,9 @@ func TestRepositoriesService_EnablePagesWorkflow(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		var v *createPagesRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeEnablePagesAPIPreview)
-		want := &createPagesRequest{BuildType: Ptr("workflow")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"build_type":"workflow"}`)
 
 		fmt.Fprint(w, `{"url":"u","status":"s","cname":"c","custom_404":false,"html_url":"h","build_type": "workflow"}`)
 	})
@@ -135,14 +120,8 @@ func TestRepositoriesService_UpdatePagesLegacy(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		var v *PagesUpdate
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		want := &PagesUpdate{CNAME: Ptr("www.example.com"), BuildType: Ptr("legacy"), Source: &PagesSource{Branch: Ptr("gh-pages")}}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"cname":"www.example.com","build_type":"legacy","source":{"branch":"gh-pages"}}`)
 
 		fmt.Fprint(w, `{"cname":"www.example.com","build_type":"legacy","source":{"branch":"gh-pages"}}`)
 	})
@@ -174,14 +153,8 @@ func TestRepositoriesService_UpdatePagesWorkflow(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		var v *PagesUpdate
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		want := &PagesUpdate{CNAME: Ptr("www.example.com"), BuildType: Ptr("workflow")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"cname":"www.example.com","build_type":"workflow"}`)
 
 		fmt.Fprint(w, `{"cname":"www.example.com","build_type":"workflow"}`)
 	})
@@ -212,14 +185,8 @@ func TestRepositoriesService_UpdatePagesGHES(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		var v *PagesUpdate
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		want := &PagesUpdate{BuildType: Ptr("workflow")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"build_type":"workflow"}`)
 
 		fmt.Fprint(w, `{"build_type":"workflow"}`)
 	})
@@ -250,15 +217,7 @@ func TestRepositoriesService_UpdatePages_NullCNAME(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/pages", func(w http.ResponseWriter, r *http.Request) {
-		got, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Fatalf("unable to read body: %v", err)
-		}
-
-		want := []byte(`{"cname":null,"source":{"branch":"gh-pages"}}` + "\n")
-		if !bytes.Equal(got, want) {
-			t.Errorf("Request body = %+v, want %+v", got, want)
-		}
+		testJSONBody(t, r, `{"cname":null,"source":{"branch":"gh-pages"}}`)
 
 		fmt.Fprint(w, `{"cname":null,"source":{"branch":"gh-pages"}}`)
 	})
diff --git a/github/repos_prereceive_hooks_test.go b/github/repos_prereceive_hooks_test.go
index daac60beeca..61c91f0f8ec 100644
--- a/github/repos_prereceive_hooks_test.go
+++ b/github/repos_prereceive_hooks_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -111,16 +110,13 @@ func TestRepositoriesService_UpdatePreReceiveHook(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &PreReceiveHook{}
+	input := &PreReceiveHook{
+		ID: Ptr(int64(1)),
+	}
 
 	mux.HandleFunc("/repos/o/r/pre-receive-hooks/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *PreReceiveHook
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"id":1}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/repos_releases_test.go b/github/repos_releases_test.go
index 18fd41bab9e..61f33919946 100644
--- a/github/repos_releases_test.go
+++ b/github/repos_releases_test.go
@@ -7,7 +7,6 @@ package github
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -59,7 +58,7 @@ func TestRepositoriesService_GenerateReleaseNotes(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/releases/generate-notes", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"tag_name":"v1.0.0"}`+"\n")
+		testJSONBody(t, r, `{"tag_name":"v1.0.0"}`)
 		fmt.Fprint(w, `{"name":"v1.0.0","body":"**Full Changelog**: https://github.com/o/r/compare/v0.9.0...v1.0.0"}`)
 	})
 
@@ -224,18 +223,9 @@ func TestRepositoriesService_CreateRelease(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/releases", func(w http.ResponseWriter, r *http.Request) {
-		var v *repositoryReleaseRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &repositoryReleaseRequest{
-			Name:                   Ptr("v1.0"),
-			DiscussionCategoryName: Ptr("General"),
-			GenerateReleaseNotes:   Ptr(true),
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"v1.0","generate_release_notes":true,"discussion_category_name":"General"}`)
+
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
@@ -294,17 +284,9 @@ func TestRepositoriesService_EditRelease(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/o/r/releases/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *repositoryReleaseRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		want := &repositoryReleaseRequest{
-			Name:                   Ptr("n"),
-			DiscussionCategoryName: Ptr("General"),
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"n","discussion_category_name":"General"}`)
+
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
@@ -626,13 +608,9 @@ func TestRepositoriesService_EditReleaseAsset(t *testing.T) {
 	input := &ReleaseAsset{Name: Ptr("n")}
 
 	mux.HandleFunc("/repos/o/r/releases/assets/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *ReleaseAsset
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
+
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
@@ -752,7 +730,7 @@ func TestRepositoriesService_UploadReleaseAsset(t *testing.T) {
 			testHeader(t, r, "Content-Type", test.expectedMediaType)
 			testHeader(t, r, "Content-Length", "12")
 			testFormValues(t, r, test.expectedFormValues)
-			testBody(t, r, "Upload me !\n")
+			testPlainBody(t, r, "Upload me !\n")
 
 			fmt.Fprint(w, `{"id":1}`)
 		})
@@ -957,7 +935,7 @@ func TestRepositoriesService_UploadReleaseAssetFromRelease(t *testing.T) {
 		testHeader(t, r, "Content-Type", mediaTypeTextPlain)
 		testHeader(t, r, "Content-Length", "12")
 		testFormValues(t, r, defaultExpectedFormValue)
-		testBody(t, r, "Upload me !\n")
+		testPlainBody(t, r, "Upload me !\n")
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -1078,7 +1056,7 @@ func TestRepositoriesService_UploadReleaseAssetFromRelease_NoOpts(t *testing.T)
 	// No opts: we just assert that the handler is hit and body is as expected.
 	mux.HandleFunc("/repos/o/r/releases/1/assets", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, "Upload me !\n")
+		testPlainBody(t, r, "Upload me !\n")
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
diff --git a/github/repos_rules_test.go b/github/repos_rules_test.go
index c8cd936e275..bcdf5d0b054 100644
--- a/github/repos_rules_test.go
+++ b/github/repos_rules_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -70,15 +69,7 @@ func TestRepositoriesService_UpdateRuleset_OmitZero_Nil(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/repo/rulesets/42", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
-
-		var v map[string]any
-		if err := json.NewDecoder(r.Body).Decode(&v); err != nil {
-			t.Errorf("could not decode body: %v", err)
-		}
-
-		if _, ok := v["bypass_actors"]; ok {
-			t.Error("Request body contained 'bypass_actors', expected it to be omitted for nil input")
-		}
+		testJSONBody(t, r, `{"name":"ruleset","source":"","enforcement":"active"}`)
 
 		fmt.Fprint(w, `{
 			"id": 42,
@@ -109,7 +100,7 @@ func TestRepositoriesService_UpdateRuleset_OmitZero_EmptySlice(t *testing.T) {
 	mux.HandleFunc("/repos/o/repo/rulesets/42", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 
-		testBody(t, r, `{"name":"ruleset","source":"","enforcement":"active","bypass_actors":[]}`+"\n")
+		testJSONBody(t, r, `{"name":"ruleset","source":"","enforcement":"active","bypass_actors":[]}`)
 
 		fmt.Fprint(w, `{
 			"id": 42,
diff --git a/github/repos_statuses_test.go b/github/repos_statuses_test.go
index 33d960d1c22..ed75e7cc6ca 100644
--- a/github/repos_statuses_test.go
+++ b/github/repos_statuses_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -67,13 +66,9 @@ func TestRepositoriesService_CreateStatus(t *testing.T) {
 	input := RepoStatus{State: Ptr("s"), TargetURL: Ptr("t"), Description: Ptr("d")}
 
 	mux.HandleFunc("/repos/o/r/statuses/r", func(w http.ResponseWriter, r *http.Request) {
-		var v *RepoStatus
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"state":"s","target_url":"t","description":"d"}`)
+
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
diff --git a/github/repos_tags_test.go b/github/repos_tags_test.go
index f9bd618ff1c..616da71680a 100644
--- a/github/repos_tags_test.go
+++ b/github/repos_tags_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -66,14 +65,8 @@ func TestRepositoriesService_CreateTagProtection(t *testing.T) {
 	pattern := "tag*"
 
 	mux.HandleFunc("/repos/o/r/tags/protection", func(w http.ResponseWriter, r *http.Request) {
-		var v *tagProtectionRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		want := &tagProtectionRequest{Pattern: "tag*"}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"pattern":"tag*"}`)
 
 		fmt.Fprint(w, `{"id":1,"pattern":"tag*"}`)
 	})
diff --git a/github/repos_test.go b/github/repos_test.go
index ce5be03c187..2597a2ad67c 100644
--- a/github/repos_test.go
+++ b/github/repos_test.go
@@ -229,15 +229,9 @@ func TestRepositoriesService_Create_user(t *testing.T) {
 
 	wantAcceptHeaders := []string{mediaTypeRepositoryTemplatePreview, mediaTypeRepositoryVisibilityPreview}
 	mux.HandleFunc("/user/repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *createRepoRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		want := &createRepoRequest{Name: Ptr("n")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -283,15 +277,9 @@ func TestRepositoriesService_Create_org(t *testing.T) {
 
 	wantAcceptHeaders := []string{mediaTypeRepositoryTemplatePreview, mediaTypeRepositoryVisibilityPreview}
 	mux.HandleFunc("/orgs/o/repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *createRepoRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		want := &createRepoRequest{Name: Ptr("n")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -323,22 +311,9 @@ func TestRepositoriesService_Create_withCustomProperties(t *testing.T) {
 
 	wantAcceptHeaders := []string{mediaTypeRepositoryTemplatePreview, mediaTypeRepositoryVisibilityPreview}
 	mux.HandleFunc("/orgs/o/repos", func(w http.ResponseWriter, r *http.Request) {
-		var v *createRepoRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		want := &createRepoRequest{
-			Name: Ptr("n"),
-			CustomProperties: map[string]any{
-				"environment": "production",
-				"team":        "backend",
-				"priority":    float64(1), // JSON unmarshals numbers as float64
-			},
-		}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"n","custom_properties":{"environment":"production","priority":1,"team":"backend"}}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -364,15 +339,9 @@ func TestRepositoriesService_CreateFromTemplate(t *testing.T) {
 	}
 
 	mux.HandleFunc("/repos/to/tr/generate", func(w http.ResponseWriter, r *http.Request) {
-		var v *TemplateRepoRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
 		testHeader(t, r, "Accept", mediaTypeRepositoryTemplatePreview)
-		want := &TemplateRepoRequest{Name: Ptr("n")}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
 
 		fmt.Fprint(w, `{"id":1,"name":"n"}`)
 	})
@@ -528,14 +497,10 @@ func TestRepositoriesService_Edit(t *testing.T) {
 
 	wantAcceptHeaders := []string{mediaTypeRepositoryTemplatePreview, mediaTypeRepositoryVisibilityPreview}
 	mux.HandleFunc("/repos/o/r", func(w http.ResponseWriter, r *http.Request) {
-		var v *Repository
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
 		testHeader(t, r, "Accept", strings.Join(wantAcceptHeaders, ", "))
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"has_issues":true}`)
+
 		fmt.Fprint(w, `{"id":1}`)
 	})
 
@@ -1148,14 +1113,8 @@ func TestRepositoriesService_RenameBranch(t *testing.T) {
 			renameBranchReq := "nn"
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *renameBranchRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "POST")
-				want := &renameBranchRequest{NewName: renameBranchReq}
-				if !cmp.Equal(v, want) {
-					t.Errorf("Request body = %+v, want %+v", v, want)
-				}
+				testJSONBody(t, r, `{"new_name":"nn"}`)
 
 				fmt.Fprint(w, `{"protected":true,"name":"nn"}`)
 			})
@@ -1512,15 +1471,10 @@ func TestRepositoriesService_UpdateBranchProtection_Contexts(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
-
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"required_status_checks":{"strict":true,"contexts":["continuous-integration"]},"required_pull_request_reviews":{"bypass_pull_request_allowances":{"users":["uuu"],"teams":["ttt"],"apps":["aaa"]},"dismissal_restrictions":{"users":["uu"],"teams":["tt"],"apps":["aa"]},"dismiss_stale_reviews":true,"require_code_owner_reviews":false,"required_approving_review_count":0},"enforce_admins":false,"restrictions":{"users":["u"],"teams":["t"],"apps":["a"]},"block_creations":true,"lock_branch":true,"allow_fork_syncing":true}`)
+
 				fmt.Fprint(w, `{
 					"required_status_checks":{
 						"strict":true,
@@ -1700,15 +1654,10 @@ func TestRepositoriesService_UpdateBranchProtection_EmptyContexts(t *testing.T)
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
-
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"required_status_checks":{"strict":true,"contexts":[]},"required_pull_request_reviews":{"bypass_pull_request_allowances":{"users":["uuu"],"teams":["ttt"],"apps":["aaa"]},"dismissal_restrictions":{"users":["uu"],"teams":["tt"],"apps":["aa"]},"dismiss_stale_reviews":true,"require_code_owner_reviews":false,"required_approving_review_count":0},"enforce_admins":false,"restrictions":{"users":["u"],"teams":["t"],"apps":["a"]},"block_creations":true,"lock_branch":true,"allow_fork_syncing":true}`)
+
 				fmt.Fprint(w, `{
 					"required_status_checks":{
 						"strict":true,
@@ -1879,15 +1828,10 @@ func TestRepositoriesService_UpdateBranchProtection_Checks(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
-
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"required_status_checks":{"strict":true,"checks":[{"context":"continuous-integration"}]},"required_pull_request_reviews":{"bypass_pull_request_allowances":{"users":["uuu"],"teams":["ttt"],"apps":["aaa"]},"dismissal_restrictions":{"users":["uu"],"teams":["tt"],"apps":["aa"]},"dismiss_stale_reviews":true,"require_code_owner_reviews":false,"required_approving_review_count":0},"enforce_admins":false,"restrictions":{"users":["u"],"teams":["t"],"apps":["a"]}}`)
+
 				fmt.Fprint(w, `{
 					"required_status_checks":{
 						"strict":true,
@@ -2032,15 +1976,10 @@ func TestRepositoriesService_UpdateBranchProtection_EmptyChecks(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
-
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"required_status_checks":{"strict":true,"checks":[]},"required_pull_request_reviews":{"bypass_pull_request_allowances":{"users":["uuu"],"teams":["ttt"],"apps":["aaa"]},"dismissal_restrictions":{"users":["uu"],"teams":["tt"],"apps":["aa"]},"dismiss_stale_reviews":true,"require_code_owner_reviews":false,"required_approving_review_count":0},"enforce_admins":false,"restrictions":{"users":["u"],"teams":["t"],"apps":["a"]}}`)
+
 				fmt.Fprint(w, `{
 					"required_status_checks":{
 						"strict":true,
@@ -2174,15 +2113,10 @@ func TestRepositoriesService_UpdateBranchProtection_StrictNoChecks(t *testing.T)
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
-
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"required_status_checks":{"strict":true},"required_pull_request_reviews":{"bypass_pull_request_allowances":{"users":["uuu"],"teams":["ttt"],"apps":["aaa"]},"dismissal_restrictions":{"users":["uu"],"teams":["tt"],"apps":["aa"]},"dismiss_stale_reviews":true,"require_code_owner_reviews":false,"required_approving_review_count":0},"enforce_admins":false,"restrictions":{"users":["u"],"teams":["t"],"apps":["a"]}}`)
+
 				fmt.Fprint(w, `{
 					"required_status_checks":{
 						"strict":true,
@@ -2298,13 +2232,8 @@ func TestRepositoriesService_UpdateBranchProtection_RequireLastPushApproval(t *t
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *ProtectionRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PUT")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
+				testJSONBody(t, r, `{"required_status_checks":null,"required_pull_request_reviews":{"dismiss_stale_reviews":false,"require_code_owner_reviews":false,"required_approving_review_count":0,"require_last_push_approval":true},"enforce_admins":false,"restrictions":null}`)
 
 				fmt.Fprint(w, `{
 					"required_pull_request_reviews":{
@@ -2564,14 +2493,10 @@ func TestRepositoriesService_UpdateRequiredStatusChecks_Contexts(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *RequiredStatusChecksRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PATCH")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
 				testHeader(t, r, "Accept", mediaTypeV3)
+				testJSONBody(t, r, `{"strict":true,"contexts":["continuous-integration"]}`)
+
 				fmt.Fprint(w, `{
 					"strict":true,
 					"contexts":["continuous-integration"],
@@ -2655,14 +2580,10 @@ func TestRepositoriesService_UpdateRequiredStatusChecks_Checks(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *RequiredStatusChecksRequest
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PATCH")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
 				testHeader(t, r, "Accept", mediaTypeV3)
+				testJSONBody(t, r, `{"strict":true,"checks":[{"context":"continuous-integration"},{"context":"continuous-integration2","app_id":123},{"context":"continuous-integration3","app_id":-1}]}`)
+
 				fmt.Fprint(w, `{
 					"strict":true,
 					"contexts":["continuous-integration"],
@@ -2937,14 +2858,10 @@ func TestRepositoriesService_UpdatePullRequestReviewEnforcement(t *testing.T) {
 			}
 
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
-				var v *PullRequestReviewsEnforcementUpdate
-				assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 				testMethod(t, r, "PATCH")
-				if !cmp.Equal(v, input) {
-					t.Errorf("Request body = %+v, want %+v", v, input)
-				}
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
+				testJSONBody(t, r, `{"dismissal_restrictions":{"users":["u"],"teams":["t"],"apps":["a"]},"required_approving_review_count":0}`)
+
 				fmt.Fprint(w, `{
 					"dismissal_restrictions":{
 						"users":[{"id":1,"login":"u"}],
@@ -3018,7 +2935,7 @@ func TestRepositoriesService_DisableDismissalRestrictions(t *testing.T) {
 			mux.HandleFunc(test.urlPath, func(w http.ResponseWriter, r *http.Request) {
 				testMethod(t, r, "PATCH")
 				testHeader(t, r, "Accept", mediaTypeRequiredApprovingReviewsPreview)
-				testBody(t, r, `{"dismissal_restrictions":{}}`+"\n")
+				testJSONBody(t, r, `{"dismissal_restrictions":{}}`)
 				fmt.Fprint(w, `{"dismiss_stale_reviews":true,"require_code_owner_reviews":true,"required_approving_review_count":1}`)
 			})
 
@@ -3575,7 +3492,7 @@ func TestRepositoriesService_ReplaceAllTopics_nilSlice(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/topics", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeTopicsPreview)
-		testBody(t, r, `{"names":[]}`+"\n")
+		testJSONBody(t, r, `{"names":[]}`)
 		fmt.Fprint(w, `{"names":[]}`)
 	})
 
@@ -3598,7 +3515,7 @@ func TestRepositoriesService_ReplaceAllTopics_emptySlice(t *testing.T) {
 	mux.HandleFunc("/repos/o/r/topics", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeTopicsPreview)
-		testBody(t, r, `{"names":[]}`+"\n")
+		testJSONBody(t, r, `{"names":[]}`)
 		fmt.Fprint(w, `{"names":[]}`)
 	})
 
@@ -4194,13 +4111,8 @@ func TestRepositoriesService_Transfer(t *testing.T) {
 	input := TransferRequest{NewOwner: "a", NewName: Ptr("b"), TeamID: []int64{123}}
 
 	mux.HandleFunc("/repos/o/r/transfer", func(w http.ResponseWriter, r *http.Request) {
-		var v TransferRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"new_owner":"a","new_name":"b","team_ids":[123]}`)
 
 		fmt.Fprint(w, `{"owner":{"login":"a"}}`)
 	})
@@ -4233,55 +4145,51 @@ func TestRepositoriesService_Transfer(t *testing.T) {
 
 func TestRepositoriesService_Dispatch(t *testing.T) {
 	t.Parallel()
-	client, mux, _ := setup(t)
-
-	var input DispatchRequestOptions
 
-	mux.HandleFunc("/repos/o/r/dispatches", func(w http.ResponseWriter, r *http.Request) {
-		var v DispatchRequestOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
-
-		fmt.Fprint(w, `{"owner":{"login":"a"}}`)
-	})
-
-	ctx := t.Context()
-
-	testCases := []any{
-		nil,
-		struct {
-			Foo string
-		}{
-			Foo: "test",
+	testCases := []DispatchRequestOptions{
+		{
+			EventType: "go1",
 		},
-		struct {
-			Bar int
-		}{
-			Bar: 42,
+		{
+			EventType: "go2",
+			ClientPayload: func() *json.RawMessage {
+				return Ptr(json.RawMessage(`{"Foo":"test"}`))
+			}(),
 		},
-		struct {
-			Foo string
-			Bar int
-			Baz bool
-		}{
-			Foo: "test",
-			Bar: 42,
-			Baz: false,
+		{
+			EventType: "go3",
+			ClientPayload: func() *json.RawMessage {
+				return Ptr(json.RawMessage(`{"Bar":42}`))
+			}(),
+		},
+		{
+			EventType: "go4",
+			ClientPayload: func() *json.RawMessage {
+				return Ptr(json.RawMessage(`{"Foo":"test","Bar":42,"Baz":false}`))
+			}(),
 		},
 	}
 
-	for _, tc := range testCases {
-		if tc == nil {
-			input = DispatchRequestOptions{EventType: "go"}
-		} else {
-			bytes, _ := json.Marshal(tc)
-			payload := json.RawMessage(bytes)
-			input = DispatchRequestOptions{EventType: "go", ClientPayload: &payload}
-		}
+	for _, input := range testCases {
+		client, mux, _ := setup(t)
+
+		mux.HandleFunc("/repos/o/r/dispatches", func(w http.ResponseWriter, r *http.Request) {
+			testMethod(t, r, "POST")
+			switch input.EventType {
+			case "go1":
+				testJSONBody(t, r, `{"event_type":"go1"}`)
+			case "go2":
+				testJSONBody(t, r, `{"event_type":"go2","client_payload":{"Foo":"test"}}`)
+			case "go3":
+				testJSONBody(t, r, `{"event_type":"go3","client_payload":{"Bar":42}}`)
+			case "go4":
+				testJSONBody(t, r, `{"event_type":"go4","client_payload":{"Foo":"test","Bar":42,"Baz":false}}`)
+			}
+
+			fmt.Fprint(w, `{"owner":{"login":"a"}}`)
+		})
+
+		ctx := t.Context()
 
 		got, _, err := client.Repositories.Dispatch(ctx, "o", "r", input)
 		if err != nil {
@@ -4294,6 +4202,11 @@ func TestRepositoriesService_Dispatch(t *testing.T) {
 		}
 	}
 
+	input := DispatchRequestOptions{EventType: "go"}
+
+	client, _, _ := setup(t)
+	ctx := t.Context()
+
 	const methodName = "Dispatch"
 	testBadOptions(t, methodName, func() (err error) {
 		_, _, err = client.Repositories.Dispatch(ctx, "\n", "\n", input)
diff --git a/github/secret_scanning_test.go b/github/secret_scanning_test.go
index c2c672f09a8..8050133a5a0 100644
--- a/github/secret_scanning_test.go
+++ b/github/secret_scanning_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -354,15 +353,7 @@ func TestSecretScanningService_UpdateAlert(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/secret-scanning/alerts/1", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-
-		var v *SecretScanningAlertUpdateOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		want := &SecretScanningAlertUpdateOptions{State: "resolved", Resolution: Ptr("used_in_tests")}
-
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"state":"resolved","resolution":"used_in_tests"}`)
 
 		fmt.Fprint(w, `{
 			"number": 1,
@@ -626,12 +617,7 @@ func TestSecretScanningService_CreatePushProtectionBypass(t *testing.T) {
 
 	mux.HandleFunc(fmt.Sprintf("/repos/%v/%v/secret-scanning/push-protection-bypasses", owner, repo), func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		var v *PushProtectionBypassRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-		want := &PushProtectionBypassRequest{Reason: "valid reason", PlaceholderID: "bypass-123"}
-		if !cmp.Equal(v, want) {
-			t.Errorf("Request body = %+v, want %+v", v, want)
-		}
+		testJSONBody(t, r, `{"reason":"valid reason","placeholder_id":"bypass-123"}`)
 
 		fmt.Fprint(w, `{
 			"reason": "valid reason",
diff --git a/github/sub_issue_test.go b/github/sub_issue_test.go
index 6c898b7e147..c2ed685f6f0 100644
--- a/github/sub_issue_test.go
+++ b/github/sub_issue_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -21,13 +20,8 @@ func TestSubIssuesService_Add(t *testing.T) {
 	input := &SubIssueRequest{SubIssueID: 42}
 
 	mux.HandleFunc("/repos/o/r/issues/1/sub_issues", func(w http.ResponseWriter, r *http.Request) {
-		var v *SubIssueRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"sub_issue_id":42}`)
 
 		fmt.Fprint(w, `{"id":42, "number":1}`)
 	})
@@ -104,13 +98,8 @@ func TestSubIssuesService_Remove(t *testing.T) {
 	input := &SubIssueRequest{SubIssueID: 42}
 
 	mux.HandleFunc("/repos/o/r/issues/1/sub_issue", func(w http.ResponseWriter, r *http.Request) {
-		var v *SubIssueRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "DELETE")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"sub_issue_id":42}`)
 
 		fmt.Fprint(w, `{"id":42, "number":1}`)
 	})
@@ -144,14 +133,7 @@ func TestSubIssuesService_Reprioritize(t *testing.T) {
 
 	mux.HandleFunc("/repos/o/r/issues/1/sub_issues/priority", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PATCH")
-
-		var v *SubIssueRequest
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"sub_issue_id":42,"after_id":5}`)
 
 		fmt.Fprint(w, `{"id":42, "number":1}`)
 	})
diff --git a/github/teams_discussion_comments_test.go b/github/teams_discussion_comments_test.go
index a451ed92639..b6c0f53917d 100644
--- a/github/teams_discussion_comments_test.go
+++ b/github/teams_discussion_comments_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -245,13 +244,8 @@ func TestTeamsService_CreateComment(t *testing.T) {
 	input := DiscussionComment{Body: Ptr("c")}
 
 	handlerFunc := func(w http.ResponseWriter, r *http.Request) {
-		var v *DiscussionComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"c"}`)
 
 		fmt.Fprint(w, `{"number":4}`)
 	}
@@ -317,13 +311,8 @@ func TestTeamsService_EditComment(t *testing.T) {
 
 	input := DiscussionComment{Body: Ptr("e")}
 	handlerFunc := func(w http.ResponseWriter, r *http.Request) {
-		var v *DiscussionComment
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"e"}`)
 
 		fmt.Fprint(w, `{"number":4}`)
 	}
diff --git a/github/teams_discussions_test.go b/github/teams_discussions_test.go
index 8e924fad55c..49c8d5af896 100644
--- a/github/teams_discussions_test.go
+++ b/github/teams_discussions_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -322,13 +321,8 @@ func TestTeamsService_CreateDiscussionByID(t *testing.T) {
 	input := TeamDiscussion{Title: Ptr("c_t"), Body: Ptr("c_b")}
 
 	mux.HandleFunc("/organizations/1/team/2/discussions", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamDiscussion
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"c_b","title":"c_t"}`)
 
 		fmt.Fprint(w, `{"number":3}`)
 	})
@@ -366,13 +360,8 @@ func TestTeamsService_CreateDiscussionBySlug(t *testing.T) {
 	input := TeamDiscussion{Title: Ptr("c_t"), Body: Ptr("c_b")}
 
 	mux.HandleFunc("/orgs/o/teams/s/discussions", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamDiscussion
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"c_b","title":"c_t"}`)
 
 		fmt.Fprint(w, `{"number":3}`)
 	})
@@ -410,13 +399,8 @@ func TestTeamsService_EditDiscussionByID(t *testing.T) {
 	input := TeamDiscussion{Title: Ptr("e_t"), Body: Ptr("e_b")}
 
 	mux.HandleFunc("/organizations/1/team/2/discussions/3", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamDiscussion
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"e_b","title":"e_t"}`)
 
 		fmt.Fprint(w, `{"number":3}`)
 	})
@@ -454,13 +438,8 @@ func TestTeamsService_EditDiscussionBySlug(t *testing.T) {
 	input := TeamDiscussion{Title: Ptr("e_t"), Body: Ptr("e_b")}
 
 	mux.HandleFunc("/orgs/o/teams/s/discussions/3", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamDiscussion
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"body":"e_b","title":"e_t"}`)
 
 		fmt.Fprint(w, `{"number":3}`)
 	})
diff --git a/github/teams_members_test.go b/github/teams_members_test.go
index 5234e9dbce8..09096378215 100644
--- a/github/teams_members_test.go
+++ b/github/teams_members_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -331,13 +330,8 @@ func TestTeamsService__AddTeamMembershipByID(t *testing.T) {
 	opt := &TeamAddTeamMembershipOptions{Role: "maintainer"}
 
 	mux.HandleFunc("/organizations/1/team/2/memberships/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamMembershipOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"role":"maintainer"}`)
 
 		fmt.Fprint(w, `{"url":"u", "state":"pending"}`)
 	})
@@ -375,13 +369,8 @@ func TestTeamsService__AddTeamMembershipByID_notFound(t *testing.T) {
 	opt := &TeamAddTeamMembershipOptions{Role: "maintainer"}
 
 	mux.HandleFunc("/organizations/1/team/2/memberships/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamMembershipOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"role":"maintainer"}`)
 
 		w.WriteHeader(http.StatusNotFound)
 	})
@@ -420,13 +409,8 @@ func TestTeamsService__AddTeamMembershipBySlug(t *testing.T) {
 	opt := &TeamAddTeamMembershipOptions{Role: "maintainer"}
 
 	mux.HandleFunc("/orgs/o/teams/s/memberships/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamMembershipOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"role":"maintainer"}`)
 
 		fmt.Fprint(w, `{"url":"u", "state":"pending"}`)
 	})
@@ -464,13 +448,8 @@ func TestTeamsService__AddTeamMembershipBySlug_notFound(t *testing.T) {
 	opt := &TeamAddTeamMembershipOptions{Role: "maintainer"}
 
 	mux.HandleFunc("/orgs/o/teams/s/memberships/u", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamMembershipOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"role":"maintainer"}`)
 
 		w.WriteHeader(http.StatusNotFound)
 	})
diff --git a/github/teams_test.go b/github/teams_test.go
index 9cef55710db..07e2422ba8e 100644
--- a/github/teams_test.go
+++ b/github/teams_test.go
@@ -6,10 +6,7 @@
 package github
 
 import (
-	"bytes"
-	"encoding/json"
 	"fmt"
-	"io"
 	"net/http"
 	"testing"
 
@@ -192,13 +189,8 @@ func TestTeamsService_CreateTeam(t *testing.T) {
 	input := NewTeam{Name: "n", Privacy: Ptr("closed"), RepoNames: []string{"r"}}
 
 	mux.HandleFunc("/orgs/o/teams", func(w http.ResponseWriter, r *http.Request) {
-		var v *NewTeam
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n","repo_names":["r"],"privacy":"closed"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -245,13 +237,8 @@ func TestTeamsService_EditTeamByID(t *testing.T) {
 	input := NewTeam{Name: "n", Privacy: Ptr("closed")}
 
 	mux.HandleFunc("/organizations/1/team/1", func(w http.ResponseWriter, r *http.Request) {
-		var v *NewTeam
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n","privacy":"closed"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -287,21 +274,10 @@ func TestTeamsService_EditTeamByID_RemoveParent(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	input := NewTeam{Name: "n", NotificationSetting: Ptr("notifications_enabled"), Privacy: Ptr("closed")}
-	var body string
 
 	mux.HandleFunc("/organizations/1/team/1", func(w http.ResponseWriter, r *http.Request) {
-		buf, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Errorf("Unable to read body: %v", err)
-		}
-		body = string(buf)
-		var v *NewTeam
-		assertNilError(t, json.NewDecoder(bytes.NewBuffer(buf)).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n","parent_team_id":null,"notification_setting":"notifications_enabled","privacy":"closed"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -316,10 +292,6 @@ func TestTeamsService_EditTeamByID_RemoveParent(t *testing.T) {
 	if !cmp.Equal(team, want) {
 		t.Errorf("Teams.EditTeamByID returned %+v, want %+v", team, want)
 	}
-
-	if want := `{"name":"n","parent_team_id":null,"notification_setting":"notifications_enabled","privacy":"closed"}` + "\n"; body != want {
-		t.Errorf("Teams.EditTeamByID body = %+v, want %+v", body, want)
-	}
 }
 
 func TestTeamsService_EditTeamBySlug(t *testing.T) {
@@ -329,13 +301,8 @@ func TestTeamsService_EditTeamBySlug(t *testing.T) {
 	input := NewTeam{Name: "n", Privacy: Ptr("closed")}
 
 	mux.HandleFunc("/orgs/o/teams/s", func(w http.ResponseWriter, r *http.Request) {
-		var v *NewTeam
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n","privacy":"closed"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -371,21 +338,10 @@ func TestTeamsService_EditTeamBySlug_RemoveParent(t *testing.T) {
 	client, mux, _ := setup(t)
 
 	input := NewTeam{Name: "n", NotificationSetting: Ptr("notifications_disabled"), Privacy: Ptr("closed")}
-	var body string
 
 	mux.HandleFunc("/orgs/o/teams/s", func(w http.ResponseWriter, r *http.Request) {
-		buf, err := io.ReadAll(r.Body)
-		if err != nil {
-			t.Errorf("Unable to read body: %v", err)
-		}
-		body = string(buf)
-		var v *NewTeam
-		assertNilError(t, json.NewDecoder(bytes.NewBuffer(buf)).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, &input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n","parent_team_id":null,"notification_setting":"notifications_disabled","privacy":"closed"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
@@ -400,10 +356,6 @@ func TestTeamsService_EditTeamBySlug_RemoveParent(t *testing.T) {
 	if !cmp.Equal(team, want) {
 		t.Errorf("Teams.EditTeam returned %+v, want %+v", team, want)
 	}
-
-	if want := `{"name":"n","parent_team_id":null,"notification_setting":"notifications_disabled","privacy":"closed"}` + "\n"; body != want {
-		t.Errorf("Teams.EditTeam body = %+v, want %+v", body, want)
-	}
 }
 
 func TestTeamsService_DeleteTeamByID(t *testing.T) {
@@ -791,13 +743,8 @@ func TestTeamsService_AddTeamRepoByID(t *testing.T) {
 	opt := &TeamAddTeamRepoOptions{Permission: "admin"}
 
 	mux.HandleFunc("/organizations/1/team/1/repos/owner/repo", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamRepoOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"permission":"admin"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
@@ -826,13 +773,8 @@ func TestTeamsService_AddTeamRepoBySlug(t *testing.T) {
 	opt := &TeamAddTeamRepoOptions{Permission: "admin"}
 
 	mux.HandleFunc("/orgs/org/teams/slug/repos/owner/repo", func(w http.ResponseWriter, r *http.Request) {
-		var v *TeamAddTeamRepoOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"permission":"admin"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
@@ -1161,12 +1103,7 @@ func TestTeamsService_AddTeamProjectByID(t *testing.T) {
 	mux.HandleFunc("/organizations/1/team/1/projects/1", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeProjectsPreview)
-
-		var v *TeamProjectOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"permission":"admin"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
@@ -1199,12 +1136,7 @@ func TestTeamsService_AddTeamProjectBySlug(t *testing.T) {
 	mux.HandleFunc("/orgs/o/teams/s/projects/1", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "PUT")
 		testHeader(t, r, "Accept", mediaTypeProjectsPreview)
-
-		var v *TeamProjectOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-		if !cmp.Equal(v, opt) {
-			t.Errorf("Request body = %+v, want %+v", v, opt)
-		}
+		testJSONBody(t, r, `{"permission":"admin"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/users_administration_test.go b/github/users_administration_test.go
index 084a7826cbf..ffdaa3383c2 100644
--- a/github/users_administration_test.go
+++ b/github/users_administration_test.go
@@ -6,11 +6,8 @@
 package github
 
 import (
-	"encoding/json"
 	"net/http"
 	"testing"
-
-	"github.com/google/go-cmp/cmp"
 )
 
 func TestUsersService_PromoteSiteAdmin(t *testing.T) {
@@ -98,13 +95,8 @@ func TestUsersServiceReason_Suspend(t *testing.T) {
 	input := &UserSuspendOptions{Reason: Ptr("test")}
 
 	mux.HandleFunc("/users/u/suspended", func(w http.ResponseWriter, r *http.Request) {
-		var v *UserSuspendOptions
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PUT")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"reason":"test"}`)
 
 		w.WriteHeader(http.StatusNoContent)
 	})
diff --git a/github/users_emails_test.go b/github/users_emails_test.go
index 27664047fd6..c69c4ad5f25 100644
--- a/github/users_emails_test.go
+++ b/github/users_emails_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -57,13 +56,8 @@ func TestUsersService_AddEmails(t *testing.T) {
 	input := []string{"new@example.com"}
 
 	mux.HandleFunc("/user/emails", func(w http.ResponseWriter, r *http.Request) {
-		var v []string
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `["new@example.com"]`)
 
 		fmt.Fprint(w, `[{"email":"old@example.com"}, {"email":"new@example.com"}]`)
 	})
@@ -99,13 +93,7 @@ func TestUsersService_DeleteEmails(t *testing.T) {
 	input := []string{"user@example.com"}
 
 	mux.HandleFunc("/user/emails", func(_ http.ResponseWriter, r *http.Request) {
-		var v []string
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
-		testMethod(t, r, "DELETE")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `["user@example.com"]`)
 	})
 
 	ctx := t.Context()
@@ -145,16 +133,9 @@ func TestUsersService_SetEmailVisibility(t *testing.T) {
 	t.Parallel()
 	client, mux, _ := setup(t)
 
-	input := &UserEmail{Visibility: Ptr("private")}
-
 	mux.HandleFunc("/user/email/visibility", func(w http.ResponseWriter, r *http.Request) {
-		var v *UserEmail
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"visibility":"private"}`)
 
 		fmt.Fprint(w, `[{
 			"email": "user@example.com",
diff --git a/github/users_gpg_keys_test.go b/github/users_gpg_keys_test.go
index 87fa613005e..152dea45d51 100644
--- a/github/users_gpg_keys_test.go
+++ b/github/users_gpg_keys_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -130,15 +129,8 @@ mQINBFcEd9kBEACo54TDbGhKlXKWMvJgecEUKPPcv7XdnpKdGb3LRw5MvFwT0V0f
 -----END PGP PUBLIC KEY BLOCK-----`
 
 	mux.HandleFunc("/user/gpg_keys", func(w http.ResponseWriter, r *http.Request) {
-		var gpgKey struct {
-			ArmoredPublicKey *string `json:"armored_public_key,omitempty"`
-		}
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&gpgKey))
-
 		testMethod(t, r, "POST")
-		if gpgKey.ArmoredPublicKey == nil || *gpgKey.ArmoredPublicKey != input {
-			t.Errorf("gpgKey = %+v, want %q", gpgKey, input)
-		}
+		testJSONBody(t, r, `{"armored_public_key":"\n-----BEGIN PGP PUBLIC KEY BLOCK-----\nComment: GPGTools - https://gpgtools.org\n\nmQINBFcEd9kBEACo54TDbGhKlXKWMvJgecEUKPPcv7XdnpKdGb3LRw5MvFwT0V0f\n...\n=tqfb\n-----END PGP PUBLIC KEY BLOCK-----"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/users_keys_test.go b/github/users_keys_test.go
index efb089bb6b3..ceb58660adf 100644
--- a/github/users_keys_test.go
+++ b/github/users_keys_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -123,13 +122,8 @@ func TestUsersService_CreateKey(t *testing.T) {
 	input := &Key{Key: Ptr("k"), Title: Ptr("t")}
 
 	mux.HandleFunc("/user/keys", func(w http.ResponseWriter, r *http.Request) {
-		var v *Key
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"key":"k","title":"t"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/users_social_accounts_test.go b/github/users_social_accounts_test.go
index cf0d3df8d26..1aad601c1e8 100644
--- a/github/users_social_accounts_test.go
+++ b/github/users_social_accounts_test.go
@@ -58,7 +58,7 @@ func TestUsersService_AddSocialAccounts(t *testing.T) {
 
 	mux.HandleFunc("/user/social_accounts", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "POST")
-		testBody(t, r, `{"account_urls":["https://example.com"]}`+"\n")
+		testJSONBody(t, r, `{"account_urls":["https://example.com"]}`)
 		fmt.Fprint(w, `[{"provider":"example","url":"https://example.com"}]`)
 	})
 
@@ -94,7 +94,7 @@ func TestUsersService_DeleteSocialAccounts(t *testing.T) {
 
 	mux.HandleFunc("/user/social_accounts", func(w http.ResponseWriter, r *http.Request) {
 		testMethod(t, r, "DELETE")
-		testBody(t, r, `{"account_urls":["https://example.com"]}`+"\n")
+		testJSONBody(t, r, `{"account_urls":["https://example.com"]}`)
 		w.WriteHeader(http.StatusNoContent)
 	})
 
diff --git a/github/users_ssh_signing_keys_test.go b/github/users_ssh_signing_keys_test.go
index f5fdd2d28f9..4dfa4e19630 100644
--- a/github/users_ssh_signing_keys_test.go
+++ b/github/users_ssh_signing_keys_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -123,13 +122,8 @@ func TestUsersService_CreateSSHSigningKey(t *testing.T) {
 	input := &Key{Key: Ptr("k"), Title: Ptr("t")}
 
 	mux.HandleFunc("/user/ssh_signing_keys", func(w http.ResponseWriter, r *http.Request) {
-		var v *Key
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "POST")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"key":"k","title":"t"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})
diff --git a/github/users_test.go b/github/users_test.go
index 3cfa7151bfa..d2624d65296 100644
--- a/github/users_test.go
+++ b/github/users_test.go
@@ -6,7 +6,6 @@
 package github
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"testing"
@@ -257,13 +256,8 @@ func TestUsersService_Edit(t *testing.T) {
 	input := &User{Name: Ptr("n")}
 
 	mux.HandleFunc("/user", func(w http.ResponseWriter, r *http.Request) {
-		var v *User
-		assertNilError(t, json.NewDecoder(r.Body).Decode(&v))
-
 		testMethod(t, r, "PATCH")
-		if !cmp.Equal(v, input) {
-			t.Errorf("Request body = %+v, want %+v", v, input)
-		}
+		testJSONBody(t, r, `{"name":"n"}`)
 
 		fmt.Fprint(w, `{"id":1}`)
 	})