avoid accidentally thawing git-annex symlink

It did nothing, since at this point the link is dangling. But when there
is a thaw hook, it would probably not be happy to be asked to run on a
symlink, or might do something unexpected.

Sponsored-by: Dartmouth College's Datalad project

Annex/Content.hs

@@ -631,15 +631,16 @@ removeAnnex (ContentRemovalLock key) = withObjectLoc key $ \file ->
   where
 	-- Check associated pointer file for modifications, and reset if
 	-- it's unmodified.
-	resetpointer file = ifM (isUnmodified key file)
-		( adjustedBranchRefresh (AssociatedFile (Just file)) $
-			depopulatePointerFile key file
-		-- Modified file, so leave it alone.
-		-- If it was a hard link to the annex object,
-		-- that object might have been frozen as part of the
-		-- removal process, so thaw it.
-		, void $ tryIO $ thawContent file
-		)
+	resetpointer file = unlessM (liftIO $ isSymbolicLink <$> getSymbolicLinkStatus (fromRawFilePath file)) $
+		ifM (isUnmodified key file)
+			( adjustedBranchRefresh (AssociatedFile (Just file)) $
+				depopulatePointerFile key file
+			-- Modified file, so leave it alone.
+			-- If it was a hard link to the annex object,
+			-- that object might have been frozen as part of the
+			-- removal process, so thaw it.
+			, void $ tryIO $ thawContent file
+			)
 
 {- Moves a key out of .git/annex/objects/ into .git/annex/bad, and
  - returns the file it was moved to. -}

doc/bugs/can__39__t_make_annex_happy_in_freeze__47__thaw.mdwn

@@ -175,3 +175,5 @@ filing as a bug since I think I satisfied all desires of git-annex for ensuring
 
 
 edit 1:  I thought that may be "Locking down a directory only needs to do the equivilant of removing its write bit, does not need to lockdown the files within it." from [lockdown_hooks](https://git-annex.branchable.com/todo/lockdown_hooks/) does not really "work", so I added `-R` to above nfs4_facl calls, but seems the effect is the same -- annex doesn' like me :-/
+
+> [[fixed|done]] --[[Joey]]

doc/bugs/can__39__t_make_annex_happy_in_freeze__47__thaw/comment_7_f0a3a944479e52a7789ff9a346001a6d._comment

@@ -0,0 +1,10 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 7"""
+ date="2022-02-24T18:13:20Z"
+ content="""
+	[2022-02-24 13:50:11.885644532] (Annex.Perms) thawing content ./foo
+
+This turns out to be due to removeAnnex's resetpointer.
+It was not intended to run on symlinks. I've fixed this too.
+"""]]