possible reversion of W.splitFileName "/\\?/a:"

[joeyh]

Before 1.4.100.2, System.FilePath.Windows.splitFileName "/\\?/a:" == ("/\\?/a:","") and in that version and since it changed to ("/\\?/","a:")

I don't fully understand Windows path semantics, and this path was generated by QuickCheck, so I don't know which is right, but 1.4.100.2 did not document any change besides optimizations. Which makes me suspect this is an unintentional change.

Also, 6a1c98d fixed a reversion in W.splitFileName "\\\\?\\A:\\fred" which seems very similar to this.

ghci> System.FilePath.Windows.splitFileName "\\\\?\\A:\\fred"
("\\\\?\\A:\\","fred")
ghci> System.FilePath.Windows.splitFileName "\\\\?\\A:\\"
("\\\\?\\A:\\","")
ghci> System.FilePath.Windows.splitFileName "\\\\?\\A:"
("\\\\?\\","A:")

[Bodigrim]

I can take a look over the next weekend.

[hasufell]

Possibly related:

• Performance improvements, up to 20x faster #183 (comment)
• Fix W.splitFileName "\\\\?\\A:\\fred" #189

[joeyh]

This same issue is discussed here #183 (comment)

[hasufell]

Do you have a proposed fix?

[Bodigrim]

I'm working on this, hopefully will finish tomorrow.