toplevel lastchanged field

Annex/MetaData/StandardFields.hs

@@ -10,6 +10,7 @@ module Annex.MetaData.StandardFields (
 	yearMetaField,
 	monthMetaField,
 	lastChangedField,
+	mkLastChangedField,
 	isLastChangedField
 ) where
 
@@ -26,13 +27,21 @@ yearMetaField = mkMetaFieldUnchecked "year"
 monthMetaField :: MetaField
 monthMetaField = mkMetaFieldUnchecked "month"
 
-lastChangedField :: MetaField -> MetaField
+lastChangedField :: MetaField
-lastChangedField f = mkMetaFieldUnchecked (fromMetaField f ++ lastchanged)
+lastChangedField = mkMetaFieldUnchecked lastchanged
+
+mkLastChangedField :: MetaField -> MetaField
+mkLastChangedField f = mkMetaFieldUnchecked (fromMetaField f ++ lastchangedSuffix)
 
 isLastChangedField :: MetaField -> Bool
-isLastChangedField f = lastchanged `isSuffixOf` s && s /= lastchanged
+isLastChangedField f
+	| f == lastChangedField = True
+	| otherwise = lastchanged `isSuffixOf` s && s /= lastchangedSuffix
   where
 	s = fromMetaField f
 
 lastchanged :: String
-lastchanged = "-lastchanged"
+lastchanged = "lastchanged"
+
+lastchangedSuffix :: String
+lastchangedSuffix = "-lastchanged"

Logs/MetaData.hs

@@ -67,16 +67,22 @@ getCurrentMetaData k = do
 	return $ currentMetaData $ unionMetaData loggedmeta
 		(lastchanged ls loggedmeta)
   where
-	lastchanged ls (MetaData wanted) =
+  	lastchanged [] _ = emptyMetaData
+	lastchanged ls (MetaData currentlyset) =
 		let m = foldl' (flip M.union) M.empty (map genlastchanged ls)
-		in MetaData $ M.mapKeys lastChangedField $
+		in MetaData $
+			-- Add a overall lastchanged using the oldest log
+			-- item (log is in ascending order).
+			M.insert lastChangedField (lastchangedval $ Prelude.last ls) $
+			M.mapKeys mkLastChangedField $
 			-- Only include fields that are currently set.
-			m `M.intersection` wanted
+			m `M.intersection` currentlyset
 	-- Makes each field have the timestamp as its value.
 	genlastchanged l =
 		let MetaData m = value l
-		    ts = S.singleton $ toMetaValue $ showts $ changed l
+		    ts = lastchangedval l
 		in M.map (const ts) m
+	lastchangedval l = S.singleton $ toMetaValue $ showts $ changed l
 	showts = formatTime defaultTimeLocale "%F@%H-%M-%S" . posixSecondsToUTCTime
 
 {- Adds in some metadata, which can override existing values, or unset

debian/changelog

@@ -27,9 +27,10 @@ git-annex (5.20140307) UNRELEASED; urgency=medium
   * map: Fix crash when one of the remotes of a repo is a local directory
     that does not exist, or is not a git repo.
   * rsync special remote: Fix slashes when used on Windows.
-  * Each for each metadata field, there's now an automatically maintained
+  * For each metadata field, there's now an automatically maintained
-    "$field-lastchanged" that gives the timestamp of the last change to that
+    "$field-lastchanged" that gives the date of the last change to that
-    field.
+    field. Also the "lastchanged" field for the date of the last change
+    to any of a file's metadata.
   * Windows: Fix some filename encoding bugs.
 
  -- Joey Hess <joeyh@debian.org>  Thu, 06 Mar 2014 16:17:01 -0400

doc/metadata.mdwn

@@ -31,6 +31,8 @@ Here are some metadata fields that git-annex has special support for:
 * `$field-lastchanged` - This is automatically maintained for each
   field that's set, and gives the date and time of the most recent
   change to the field. It cannot be modified directly.
+* `lastchanged` - This is automatically maintained, giving the data and time
+  of the last change to any of the metadata of a file.
 
 To make git-annex automatically set the year and month when adding files,
 run `git config annex.genmetadata true`. Also, see