Windows: Fix an over-long temp directory name.

Annex/ReplaceFile.hs

@@ -5,6 +5,8 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE CPP #-}
+
 module Annex.ReplaceFile where
 
 import Annex.Common
@@ -27,8 +29,17 @@ replaceFile :: FilePath -> (FilePath -> Annex ()) -> Annex ()
 replaceFile file action = do
 	misctmpdir <- fromRepo gitAnnexTmpMiscDir
 	void $ createAnnexDirectory misctmpdir
+#ifndef mingw32_HOST_OS
+	-- Use part of the filename as the template for the temp
+	-- directory. This does not need to be unique, but it
+	-- makes it more clear what this temp directory is for.
 	filemax <- liftIO $ fileNameLengthLimit misctmpdir
 	let basetmp = take (filemax `div` 2) (takeFileName file)
+#else
+	-- Windows has limits on the whole path length, so keep
+	-- it short.
+	let basetmp = "t"
+#endif
 	withTmpDirIn misctmpdir basetmp $ \tmpdir -> do
 		let tmpfile = tmpdir </> basetmp
 		action tmpfile

debian/changelog

@@ -13,6 +13,7 @@ git-annex (6.20160420) UNRELEASED; urgency=medium
   * stack.yaml: Enable explicit-setup-deps.
   * Windows: Fix several bugs in propigation of changes from the adjusted
     branch back to the master branch.
+  * Windows: Fix an over-long temp directory name.
   * map: Hide dead repositories that are not connected to the graph.
   * map: Changed colors; red is used for untrusted repositories and grey
     for dead.

doc/bugs/Excessively_long_temp_names_preventing___34__get__34___on_Windows.mdwn

@@ -35,3 +35,5 @@ OS: Windows 10
 ### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)
 
 Yes, managing 30000 files, on operating systems other than Windows though...
+
+> [[fixed|done]] --[[Joey]]

doc/bugs/Excessively_long_temp_names_preventing___34__get__34___on_Windows/comment_1_fafaff54e55e0b82df52656d8afb1c3e._comment

@@ -0,0 +1,8 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2016-05-06T16:46:22Z"
+ content="""
+Thanks for reporting this. I can't fix all the too long path problems
+on windows currently, but I can fix this particular one at least.
+"""]]