fix(routes): read Go 1.22 ServeMux method and host patterns

internal/cbm/extract_calls.c

@@ -4557,8 +4557,14 @@ CBMInvocationDescriptor handle_calls(CBMExtractCtx *ctx, TSNode node, const CBML
                 call.first_string_arg = route_path_with_group_prefix(ctx, node, call.callee_name,
                                                                      call.first_string_arg);
                 /* A slashless registration's string action would only be
-                 * guessed at (#1146): mint its Route without a handler. */
-                if (call.first_string_arg && call.first_string_arg[0] == '/' &&
+                 * guessed at (#1146): mint its Route without a handler. A Go
+                 * ServeMux pattern names its method or host before the slash
+                 * ("POST /v1/x", #2537) and keeps its handler. */
+                if (call.first_string_arg &&
+                    (call.first_string_arg[0] == '/' ||
+                     (ctx->language == CBM_LANG_GO &&
+                      cbm_service_pattern_mux_route_path(call.callee_name, call.first_string_arg) !=
+                          NULL)) &&
                     !(laravel_uri && php_route_action_is_string(node))) {
                     call.second_arg_name = extract_handler_arg(ctx, args);
                 }

internal/cbm/service_patterns.c

@@ -1183,6 +1183,65 @@ const char *cbm_service_pattern_route_method(const char *callee_name) {
     return NULL;
 }
 
+static bool mux_is_blank(char ch) {
+    return ch == ' ' || ch == '\t';
+}
+
+const char *cbm_service_pattern_mux_split(const char *pattern, char *method, size_t method_sz) {
+    if (method && method_sz > 0) {
+        method[0] = '\0';
+    }
+    if (!pattern || pattern[0] == '/') {
+        return NULL;
+    }
+    /* METHOD: Go cuts it at the first space or tab and trims the rest. */
+    const char *rest = pattern;
+    size_t method_len = 0;
+    while (pattern[method_len] >= 'A' && pattern[method_len] <= 'Z') {
+        method_len++;
+    }
+    if (method_len > 0 && mux_is_blank(pattern[method_len])) {
+        rest = pattern + method_len;
+        while (mux_is_blank(*rest)) {
+            rest++;
+        }
+    } else {
+        method_len = 0;
+    }
+    /* HOST: everything before the path's slash, with no blank or line break. */
+    const char *slash = rest;
+    while (*slash && *slash != '/' && !mux_is_blank(*slash) && *slash != '\n' && *slash != '\r') {
+        slash++;
+    }
+    if (*slash != '/' || (method_len == 0 && slash == rest)) {
+        return NULL;
+    }
+    if (method_len > 0 && method) {
+        if (method_len >= method_sz) {
+            method[0] = '\0';
+            return NULL;
+        }
+        memcpy(method, pattern, method_len);
+        method[method_len] = '\0';
+    }
+    return slash;
+}
+
+const char *cbm_service_pattern_mux_route_path(const char *callee_name, const char *pattern) {
+    static const char *const mux_callees[] = {".Handle", ".HandleFunc"};
+    if (!callee_name || !pattern || strstr(pattern, "://") != NULL) {
+        return NULL;
+    }
+    size_t clen = strlen(callee_name);
+    for (size_t i = 0; i < sizeof(mux_callees) / sizeof(mux_callees[0]); i++) {
+        size_t slen = strlen(mux_callees[i]);
+        if (clen >= slen && strcmp(callee_name + clen - slen, mux_callees[i]) == 0) {
+            return cbm_service_pattern_mux_split(pattern, NULL, 0);
+        }
+    }
+    return NULL;
+}
+
 const char *cbm_service_pattern_broker(const char *resolved_qn) {
     if (!resolved_qn) {
         return NULL;

internal/cbm/service_patterns.h

@@ -84,6 +84,25 @@ const char *cbm_service_pattern_http_method(const char *callee_name);
  * Returns NULL if not a known route registration method. */
 const char *cbm_service_pattern_route_method(const char *callee_name);
 
+/* Go 1.22+ net/http ServeMux pattern "[METHOD ][HOST]/[PATH]" (#2537):
+ * "POST /v1/x", "GET api.example.com/v1/x", "api.example.com/v1/x". Returns a
+ * pointer to PATH's leading slash inside `pattern`, or NULL when the pattern
+ * names neither a method nor a host before a slash (a plain "/v1/x" is NULL
+ * too: there is nothing to split). METHOD is a run of uppercase letters ended
+ * by spaces or tabs; it is copied to `method` (NUL-terminated, "" when the
+ * pattern names none) when `method` is non-NULL; a method that does not fit
+ * `method_sz` then makes the pattern NULL. The grammar is Go's: callers gate
+ * on the file language. */
+const char *cbm_service_pattern_mux_split(const char *pattern, char *method, size_t method_sz);
+
+/* The path of a ServeMux registration's pattern (#2537): only a callee ending
+ * ".Handle" or ".HandleFunc" registers one, and never with a URL ("://").
+ * Another route-verb call names no pattern: `store.Get("users/123")` is no
+ * host "users" + path "/123", `client.Get("https://...")` no host "https:".
+ * The split of cbm_service_pattern_mux_split for such a registration, else
+ * NULL. The grammar is Go's: callers gate on the file language. */
+const char *cbm_service_pattern_mux_route_path(const char *callee_name, const char *pattern);
+
 /* Get the broker name for an async QN (e.g., "pubsub" from a Pub/Sub QN).
  * Returns NULL if not an async pattern. */
 const char *cbm_service_pattern_broker(const char *resolved_qn);

src/pipeline/pass_calls.c

@@ -577,17 +577,34 @@ cbm_svc_kind_t cbm_pipeline_external_import_service(cbm_external_import_index_t
     return CBM_SVC_NONE;
 }
 
+/* The path a route registration's first argument names: the argument itself
+ * when it opens with a slash, or in Go the path of a ServeMux pattern that
+ * names a method or host first ("POST /v1/x", #2537; Handle / HandleFunc
+ * only). NULL when it names no path. MUST match pass_parallel.c
+ * find_route_path_in_args. */
+static const char *route_reg_path(const CBMCall *call, CBMLanguage lang) {
+    const char *arg = call->first_string_arg;
+    if (!arg) {
+        return NULL;
+    }
+    if (arg[0] == '/') {
+        return arg;
+    }
+    return cbm_pipeline_mux_route_path(call, lang);
+}
+
 /* Handle a route registration call: create Route node + HANDLES edge.
  * route_mount is the framework mount of the registering file ("/api" for a
  * Laravel 11+ `withRouting(api: ...)` file, #1146) or "". */
 static bool handle_route_registration(cbm_pipeline_ctx_t *ctx, const CBMCall *call,
                                       const cbm_gbuf_node_t *source_node, const char *module_qn,
                                       const char **imp_keys, const char **imp_vals, int imp_count,
                                       const char *route_mount, CBMLanguage lang) {
-    const char *method = cbm_service_pattern_route_method(call->callee_name);
+    char mux_method[CBM_SZ_16];
+    const char *method = cbm_pipeline_route_reg_method(call, lang, mux_method, sizeof(mux_method));
     char mounted[CBM_SZ_256];
     const char *path =
-        cbm_laravel_mount_route(route_mount, call->first_string_arg, mounted, sizeof(mounted));
+        cbm_laravel_mount_route(route_mount, route_reg_path(call, lang), mounted, sizeof(mounted));
     char route_qn[CBM_ROUTE_QN_SIZE];
     char cpath[CBM_SZ_256];
     snprintf(route_qn, sizeof(route_qn), "__route__%s__%s", method ? method : "ANY",
@@ -824,7 +841,7 @@ static bool emit_classified_edge(cbm_pipeline_ctx_t *ctx, const CBMCall *call,
                                  bool suppress_plain_calls, const char *route_mount,
                                  CBMLanguage lang) {
     cbm_svc_kind_t svc = cbm_service_pattern_match(res->qualified_name);
-    if (svc == CBM_SVC_ROUTE_REG && call->first_string_arg && call->first_string_arg[0] == '/') {
+    if (svc == CBM_SVC_ROUTE_REG && route_reg_path(call, lang) != NULL) {
         return handle_route_registration(ctx, call, source, module_qn, imp_keys, imp_vals,
                                          imp_count, route_mount, lang);
     }
@@ -924,8 +941,8 @@ static bool calls_emit_route_call(cbm_pipeline_ctx_t *ctx, const CBMCall *call,
                                   const char **imp_keys, const char **imp_vals, int imp_count,
                                   const char *route_mount, CBMLanguage lang,
                                   CBMCallEvidence *evidence) {
-    if (cbm_service_pattern_route_method(call->callee_name) == NULL || !call->first_string_arg ||
-        call->first_string_arg[0] != '/') {
+    if (cbm_service_pattern_route_method(call->callee_name) == NULL ||
+        route_reg_path(call, lang) == NULL) {
         return false;
     }
     evidence->calls_emitted |= handle_route_registration(

src/pipeline/pass_parallel.c

@@ -2272,13 +2272,42 @@ static bool is_route_path_shaped(const char *val) {
     return val && val[0] == '/' && !cbm_service_pattern_is_comment_text(val);
 }
 
-static const char *find_route_path_in_args(const CBMCall *call, const char **out_handler) {
+const char *cbm_pipeline_mux_route_path(const CBMCall *call, CBMLanguage lang) {
+    const char *arg = call->first_string_arg;
+    if (lang != CBM_LANG_GO || !arg || cbm_service_pattern_is_comment_text(arg)) {
+        return NULL;
+    }
+    return cbm_service_pattern_mux_route_path(call->callee_name, arg);
+}
+
+const char *cbm_pipeline_route_reg_method(const CBMCall *call, CBMLanguage lang, char *buf,
+                                          size_t buf_sz) {
+    const char *method = cbm_service_pattern_route_method(call->callee_name);
+    if (method && strcmp(method, "ANY") != 0) {
+        return method;
+    }
+    if (cbm_pipeline_mux_route_path(call, lang) &&
+        cbm_service_pattern_mux_split(call->first_string_arg, buf, buf_sz) && buf[0] != '\0') {
+        return buf;
+    }
+    return method;
+}
+
+static const char *find_route_path_in_args(const CBMCall *call, const char **out_handler,
+                                           CBMLanguage lang) {
     *out_handler = NULL;
     /* 1. First string arg starting with / */
     if (is_route_path_shaped(call->first_string_arg)) {
         *out_handler = call->second_arg_name;
         return call->first_string_arg;
     }
+    /* 1b. Go ServeMux pattern with a method or host before the path (#2537),
+     * read for Handle / HandleFunc only. MUST match pass_calls.c route_reg_path. */
+    const char *mux_path = cbm_pipeline_mux_route_path(call, lang);
+    if (mux_path) {
+        *out_handler = call->second_arg_name;
+        return mux_path;
+    }
     /* 2. Keyword args (prefix=, path=, route=, etc.) */
     const char *found = NULL;
     for (int ai = 0; ai < call->arg_count && !found; ai++) {
@@ -2438,7 +2467,8 @@ static bool emit_route_registration(cbm_gbuf_t *gbuf, const cbm_gbuf_node_t *sou
                                     const cbm_registry_t *registry, const cbm_gbuf_t *main_gbuf,
                                     const char **ik, const char **iv, int ic,
                                     const char *route_mount, CBMLanguage lang) {
-    const char *method = cbm_service_pattern_route_method(call->callee_name);
+    char mux_method[CBM_SZ_16];
+    const char *method = cbm_pipeline_route_reg_method(call, lang, mux_method, sizeof(mux_method));
     char mounted[CBM_SZ_256];
     route_path = cbm_laravel_mount_route(route_mount, route_path, mounted, sizeof(mounted));
     char rqn[CBM_ROUTE_QN_SIZE];
@@ -2824,7 +2854,7 @@ static bool emit_service_edge(cbm_gbuf_t *gbuf, const cbm_gbuf_node_t *source,
 
     if (svc == CBM_SVC_ROUTE_REG) {
         const char *handler_ref = NULL;
-        const char *route_path = find_route_path_in_args(call, &handler_ref);
+        const char *route_path = find_route_path_in_args(call, &handler_ref, lang);
         if (route_path) {
             return emit_route_registration(gbuf, source, call, route_path, handler_ref, module_qn,
                                            registry, main_gbuf, imp_keys, imp_vals, imp_count,
@@ -2888,7 +2918,7 @@ static bool emit_xlang_refused_route(cbm_gbuf_t *gbuf, const cbm_gbuf_node_t *so
         return false;
     }
     const char *handler_ref = NULL;
-    const char *route_path = find_route_path_in_args(call, &handler_ref);
+    const char *route_path = find_route_path_in_args(call, &handler_ref, lang);
     if (route_path) {
         return emit_route_registration(gbuf, source, call, route_path, handler_ref, module_qn,
                                        registry, main_gbuf, imp_keys, imp_vals, imp_count,

src/pipeline/pipeline_internal.h

@@ -797,6 +797,22 @@ bool cbm_pipeline_http_client_call_url(const cbm_gbuf_t *gbuf, const char *proje
  * behind both passes' HTTP_CALLS / ASYNC_CALLS props (pass_parallel.c). */
 void cbm_pipeline_close_call_props(char *props, int n, const CBMCall *call, bool with_line);
 
+/* Go 1.22 ServeMux registrations may name a method and a host before the path
+ * ("POST /v1/x", "GET api.example.com/v1/x", #2537). For a Go `Handle` /
+ * `HandleFunc` call, the path inside its first argument; NULL for any other
+ * language or callee (`store.Get("users/123")`), for a URL argument, and for an
+ * argument that is no such pattern (a plain "/v1/x" included). The one reader
+ * of that grammar behind both passes (pass_parallel.c). */
+const char *cbm_pipeline_mux_route_path(const CBMCall *call, CBMLanguage lang);
+
+/* The method of a route registration's Route: the verb its callee names
+ * (`router.GET`), else the method its Go ServeMux pattern names
+ * (`mux.HandleFunc("POST /v1/x", h)`, #2537), else the callee's own answer
+ * (ANY or NULL). `buf` (CBM_SZ_16) holds a pattern method. Shared by both
+ * passes so their Routes stay byte-identical (pass_parallel.c). */
+const char *cbm_pipeline_route_reg_method(const CBMCall *call, CBMLanguage lang, char *buf,
+                                          size_t buf_sz);
+
 /* Per-file index of the names a file's imports bind onto EXTERNAL modules:
  * local name -> the binding import. Built lazily, on the first call that
  * asks, from the file's extraction imports and its IMPORTS edges; one hash

tests/test_extraction.c

@@ -6431,6 +6431,40 @@ TEST(extract_go_binary_concat_url_no_literal_suffix_issue1249) {
     PASS();
 }
 
+/* Issue #2537: a Go 1.22 ServeMux pattern may open with a method and/or a host
+ * ("POST /v1/payments", "GET api.example.com/v1/x"). The written pattern stays
+ * the first string argument, and its handler is captured exactly as for a
+ * plain "/v1/payments"; it was dropped because the pattern does not open with
+ * a slash. */
+TEST(extract_go_servemux_method_pattern_handler_issue2537) {
+    CBMFileResult *r = extract("package main\n"
+                               "import \"net/http\"\n"
+                               "func setup(mux *http.ServeMux) {\n"
+                               "    mux.HandleFunc(\"POST /v1/payments\", createPayment)\n"
+                               "    mux.Handle(\"GET api.example.com/v1/x\", hostHandler)\n"
+                               "}\n",
+                               CBM_LANG_GO, "t", "routes.go");
+    ASSERT_NOT_NULL(r);
+    ASSERT_FALSE(r->has_error);
+
+    const CBMCall *method = find_call_by_callee(r, "mux.HandleFunc");
+    ASSERT_NOT_NULL(method);
+    ASSERT_NOT_NULL(method->first_string_arg);
+    ASSERT_STR_EQ(method->first_string_arg, "POST /v1/payments");
+    ASSERT_NOT_NULL(method->second_arg_name);
+    ASSERT_STR_EQ(method->second_arg_name, "createPayment");
+
+    const CBMCall *host = find_call_by_callee(r, "mux.Handle");
+    ASSERT_NOT_NULL(host);
+    ASSERT_NOT_NULL(host->first_string_arg);
+    ASSERT_STR_EQ(host->first_string_arg, "GET api.example.com/v1/x");
+    ASSERT_NOT_NULL(host->second_arg_name);
+    ASSERT_STR_EQ(host->second_arg_name, "hostHandler");
+
+    cbm_free_result(r);
+    PASS();
+}
+
 /* Issue #2291: the JS/TS twin of #1249. A BFF that builds its backend URL as
  * `${process.env.BACKEND_URL}/wallet/topup` from a configurable base must
  * index the literal path after the base, exactly as `BACKEND_URL + "/x"`
@@ -13907,6 +13941,7 @@ SUITE(extraction) {
     RUN_TEST(extract_ts_config_object_url_issue2235);
     RUN_TEST(extract_go_binary_concat_url_issue1249);
     RUN_TEST(extract_go_binary_concat_url_no_literal_suffix_issue1249);
+    RUN_TEST(extract_go_servemux_method_pattern_handler_issue2537);
     RUN_TEST(extract_ts_template_base_url_issue2291);
     RUN_TEST(extract_ts_template_base_url_no_literal_path_issue2291);
     RUN_TEST(extract_py_concat_const_url_issue706);

tests/test_infrascan.c

@@ -809,12 +809,61 @@ TEST(infrascan_data_flows_test_handlers_pair_only_within_their_file) {
     PASS();
 }
 
+/* Issue #2537: the Go 1.22 ServeMux grammar "[METHOD ][HOST]/[PATH]". The path
+ * is found inside the written pattern; a plain path, a lowercase word, a
+ * pattern without a path and a method too long for the buffer are no split.
+ * Only a Handle / HandleFunc registration is read with it. */
+TEST(infrascan_servemux_pattern_split_issue2537) {
+    char m[16];
+    const char *pat = "POST /v1/payments";
+    ASSERT_TRUE(cbm_service_pattern_mux_split(pat, m, sizeof(m)) == pat + 5);
+    ASSERT_STR_EQ(m, "POST");
+    pat = "GET \t /v1/payments/{id}";
+    ASSERT_TRUE(cbm_service_pattern_mux_split(pat, m, sizeof(m)) == pat + 6);
+    ASSERT_STR_EQ(m, "GET");
+    pat = "GET api.example.com/v1/x";
+    ASSERT_TRUE(cbm_service_pattern_mux_split(pat, m, sizeof(m)) == pat + 19);
+    ASSERT_STR_EQ(m, "GET");
+    pat = "api.example.com:8443/v1/x";
+    ASSERT_TRUE(cbm_service_pattern_mux_split(pat, m, sizeof(m)) == pat + 20);
+    ASSERT_STR_EQ(m, "");
+    pat = "DELETE /";
+    ASSERT_TRUE(cbm_service_pattern_mux_split(pat, NULL, 0) == pat + 7);
+
+    ASSERT_NULL(cbm_service_pattern_mux_split("/v1/x", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("get /v1/x", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("POST", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("POST ", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("GET host", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("GET a b/x", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("", m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split(NULL, m, sizeof(m)));
+    ASSERT_NULL(cbm_service_pattern_mux_split("ABCDEFGHIJKLMNOP /x", m, sizeof(m)));
+    ASSERT_STR_EQ(m, "");
+
+    /* only Handle / HandleFunc register a pattern, and never with a URL */
+    pat = "POST /v1/payments";
+    ASSERT_TRUE(cbm_service_pattern_mux_route_path("mux.HandleFunc", pat) == pat + 5);
+    pat = "api.example.com/v1/x";
+    ASSERT_TRUE(cbm_service_pattern_mux_route_path("s.mux.Handle", pat) == pat + 15);
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("st.Get", "users/123"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("c.Get", "https://api.example.com/v1/x"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("mux.Handle", "https://api.example.com/v1/x"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("PatchCollector.Delete", "storage.k8s.io/v1"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("r.Route", "GET /v1/x"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("mux.HandleFunc", "/v1/x"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path(NULL, "GET /v1/x"));
+    ASSERT_NULL(cbm_service_pattern_mux_route_path("mux.HandleFunc", NULL));
+    PASS();
+}
+
 SUITE(infrascan) {
     RUN_TEST(infrascan_http_route_literal_guard_rejects_filesystem_paths);
     RUN_TEST(infrascan_http_route_literal_guard_rejects_document_extensions);
     RUN_TEST(infrascan_client_navigation_is_js_family_only);
     RUN_TEST(infrascan_service_pattern_match_rejects_ids_inside_words);
     RUN_TEST(infrascan_service_pattern_match_keeps_real_library_qns);
+    RUN_TEST(infrascan_servemux_pattern_split_issue2537);
     RUN_TEST(infrascan_route_nodes_skip_bad_http_url_paths);
     RUN_TEST(infrascan_http_calls_join_matching_handler_route);
     RUN_TEST(infrascan_decorator_route_metadata_keeps_its_escapes);