fix transfers of key with no associated file

Several places assumed this would not happen, and when the AssociatedFile
was Nothing, did nothing.

As part of this, preferred content checks pass the Key around.

Note that checkMatcher is sometimes now called with Just Key and Just File.
It currently constructs a FileMatcher, ignoring the Key. However, if it
constructed a FileKeyMatcher, which contained both, then it might be
possible to speed up parts of Limit, which currently call the somewhat
expensive lookupFileKey to get the Key.

I have not made this optimisation yet, because I am not sure if the key is
always the same. Will need some significant checking to satisfy myself
that's the case..

1 files changed, 18 insertions, 11 deletions

diff --git a/Annex/FileMatcher.hs b/Annex/FileMatcher.hs
index c144920cf..158f3e787 100644
--- a/Annex/FileMatcher.hs
+++ b/Annex/FileMatcher.hs
@@ -1,6 +1,6 @@
 {- git-annex file matching
  -
- - Copyright 2012, 2013 Joey Hess <joey@kitenet.net>
+ - Copyright 2012-2014 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -28,18 +28,25 @@ import qualified Data.Set as S
 type FileMatcher = Matcher MatchFiles
 
 checkFileMatcher :: FileMatcher -> FilePath -> Annex Bool
-checkFileMatcher matcher file = checkFileMatcher' matcher file S.empty True
+checkFileMatcher matcher file = checkMatcher matcher Nothing (Just file) S.empty True
 
-checkFileMatcher' :: FileMatcher -> FilePath -> AssumeNotPresent -> Bool -> Annex Bool
-checkFileMatcher' matcher file notpresent def
+checkMatcher :: FileMatcher -> Maybe Key -> AssociatedFile -> AssumeNotPresent -> Bool -> Annex Bool
+checkMatcher matcher mkey afile notpresent def
 	| isEmpty matcher = return def
-	| otherwise = do
-		matchfile <- getTopFilePath <$> inRepo (toTopFilePath file)
-		let mi = MatchingFile $ FileInfo
-			{ matchFile = matchfile
-			, relFile = file
-			}
-		matchMrun matcher $ \a -> a notpresent mi
+	| otherwise = case (mkey, afile) of
+		(_, Just file) -> go =<< fileMatchInfo file
+		(Just key, _) -> go (MatchingKey key)
+		_ -> return def
+  where
+	go mi = matchMrun matcher $ \a -> a notpresent mi
+
+fileMatchInfo :: FilePath -> Annex MatchInfo
+fileMatchInfo file = do
+	matchfile <- getTopFilePath <$> inRepo (toTopFilePath file)
+	return $ MatchingFile $ FileInfo
+		{ matchFile = matchfile
+		, relFile = file
+		}
 
 matchAll :: FileMatcher
 matchAll = generate []