unlock: Fix behavior when file content is not present.

Command/Unlock.hs

@@ -12,6 +12,7 @@ import System.Directory hiding (copyFile)
 
 import Command
 import qualified Annex
+import qualified Backend
 import Types
 import Messages
 import Locations
@@ -31,8 +32,12 @@ seek = [withFilesInGit start]
  - content. -}
 start :: CommandStartString
 start file = isAnnexed file $ \(key, _) -> do
-	showStart "unlock" file
-	return $ Just $ perform file key
+	inbackend <- Backend.hasKey key
+	if not inbackend
+		then return Nothing
+		else do
+			showStart "unlock" file
+			return $ Just $ perform file key
 
 perform :: FilePath -> Key -> CommandPerform
 perform dest key = do

debian/changelog

@@ -5,6 +5,7 @@ git-annex (0.18) UNRELEASED; urgency=low
     (Did not affect ssh remotes.)
   * fsck: Fix bug in moving of corrupted files to .git/annex/bad/
   * migrate: Fix support for --backend option.
+  * unlock: Fix behavior when file content is not present.
   * Test suite improvements. Current top-level test coverage: 80%
 
  -- Joey Hess <joeyh@debian.org>  Tue, 11 Jan 2011 16:05:25 -0400

test.hs

@@ -215,6 +215,12 @@ test_copy = "git-annex copy" ~: TestCase $ intmpclonerepo $ do
 
 test_lock :: Test
 test_lock = "git-annex unlock/lock" ~: intmpclonerepo $ do
+	-- regression test: unlock of not present file should skip it
+	annexed_notpresent annexedfile
+	r <- git_annex "unlock" ["-q", annexedfile]
+	r @? "unlock failed with not present file"
+	annexed_notpresent annexedfile
+
 	git_annex "get" ["-q", annexedfile] @? "get of file failed"
 	annexed_present annexedfile
 	git_annex "unlock" ["-q", annexedfile] @? "unlock failed"		
@@ -232,8 +238,8 @@ test_lock = "git-annex unlock/lock" ~: intmpclonerepo $ do
 	runchecks [checklink, checkunwritable] annexedfile
 	c <- readFile annexedfile
 	assertEqual ("content of modified file") c (changedcontent annexedfile)
-	r <- git_annex "drop" ["-q", annexedfile]
-	(not r) @? "drop wrongly succeeded with no known copy of modified file"
+	r' <- git_annex "drop" ["-q", annexedfile]
+	not r' @? "drop wrongly succeeded with no known copy of modified file"
 
 test_edit :: Test
 test_edit = "git-annex edit/commit" ~: TestList [t False, t True]