direct mode bug fix: After a conflicted merge was automatically resolved, the content of a file that was already present could incorrectly be replaced with a symlink.

The bug was in movein, which just replaceFile'd the file with a symlink,
even if it already had the desired content, before trying to pull the
content out of the annex and replace the symlink with it.

That was ok-ish for non conflicted merges, where if the file existed it would
be an old version of the content. But for conflicted merges, the automatic
merge resolver has already run, and will have already put the desired
content into the file for the local variant.

Also, made removeDirect not trust that the associated files map is correct.
Only if it can verify that another file has the content will it not move it
into .git/annex/objects.

Annex/Direct.hs

@@ -158,13 +158,10 @@ mergeDirectCleanup d oldsha newsha = do
 		nukeFile f
 		void $ tryIO $ removeDirectory $ parentDir f
 	
-	{- The symlink is created from the key, rather than moving in the
-	 - symlink created in the temp directory by the merge. This because
-	 - a conflicted merge will write to some other file in the temp
-	 - directory.
-	 -
- 	 - Symlinks are replaced with their content, if it's available. -}
-	movein k f = do
+	{- If the file is already present, with the right content for the
+	 - key, it's left alone. Otherwise, create the symlink and then
+	 - if possible, replace it with the content. -}
+	movein k f = unlessM (goodContent k f) $ do
 		l <- inRepo $ gitAnnexLink f k
 		replaceFile f $ makeAnnexLink l
 		toDirect k f
@@ -206,12 +203,11 @@ toDirectGen k f = do
 					liftIO . void . copyFileExternal loc
 			_ -> return Nothing
 
-{- Removes a direct mode file, while retaining its content. -}
+{- Removes a direct mode file, while retaining its content in the annex. -}
 removeDirect :: Key -> FilePath -> Annex ()
 removeDirect k f = do
 	locs <- removeAssociatedFile k f
-	when (null locs) $
-		whenM (isNothing <$> getAnnexLinkTarget f) $
+	unlessM (inAnnex k) $
 		moveAnnex k f
 	liftIO $ do
 		nukeFile f

debian/changelog

@@ -12,6 +12,9 @@ git-annex (4.20130517) UNRELEASED; urgency=low
     failing to link -lHSrts_thr
   * Temporarily build without webapp on kfreebsd-i386, until yesod is
     installable there again.
+  * direct mode bug fix: After a conflicted merge was automatically resolved,
+    the content of a file that was already present could incorrectly
+    be replaced with a symlink.
 
  -- Joey Hess <joeyh@debian.org>  Fri, 17 May 2013 11:17:03 -0400