--in can now refer to files that were located in a repository at some past date. For example, --in="here@{yesterday}"

Logs/Location.hs

@@ -8,7 +8,7 @@
  - Repositories record their UUID and the date when they --get or --drop
  - a value.
  - 
- - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
+ - Copyright 2010-2014 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -18,6 +18,7 @@ module Logs.Location (
 	logStatus,
 	logChange,
 	loggedLocations,
+	loggedLocationsHistorical,
 	loggedKeys,
 	loggedKeysFor,
 ) where
@@ -27,6 +28,7 @@ import qualified Annex.Branch
 import Logs
 import Logs.Presence
 import Annex.UUID
+import Git.Types (RefDate)
 
 {- Log a change in the presence of a key's value in current repository. -}
 logStatus :: Key -> LogStatus -> Annex ()
@@ -40,10 +42,16 @@ logChange key (UUID u) s = addLog (locationLogFile key) =<< logNow s u
 logChange _ NoUUID _ = noop
 
 {- Returns a list of repository UUIDs that, according to the log, have
- - the value of a key.
- -}
+ - the value of a key. -}
 loggedLocations :: Key -> Annex [UUID]
-loggedLocations key = map toUUID <$> (currentLog . locationLogFile) key
+loggedLocations = getLoggedLocations currentLog
+
+{- Gets the location log on a particular date. -}
+loggedLocationsHistorical :: RefDate -> Key -> Annex [UUID]
+loggedLocationsHistorical = getLoggedLocations . historicalLog
+
+getLoggedLocations :: (FilePath -> Annex [String]) -> Key -> Annex [UUID]
+getLoggedLocations getter key = map toUUID <$> (getter . locationLogFile) key
 
 {- Finds all keys that have location log information.
  - (There may be duplicate keys in the list.) -}

Logs/Presence.hs

@@ -6,7 +6,7 @@
  - A line of the log will look like: "date N INFO"
  - Where N=1 when the INFO is present, and 0 otherwise.
  - 
- - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
+ - Copyright 2010-2014 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -16,7 +16,8 @@ module Logs.Presence (
 	addLog,
 	readLog,
 	logNow,
-	currentLog
+	currentLog,
+	historicalLog
 ) where
 
 import Data.Time.Clock.POSIX
@@ -24,6 +25,7 @@ import Data.Time.Clock.POSIX
 import Logs.Presence.Pure as X
 import Common.Annex
 import qualified Annex.Branch
+import Git.Types (RefDate)
 
 addLog :: FilePath -> LogLine -> Annex ()
 addLog file line = Annex.Branch.change file $ \s -> 
@@ -43,3 +45,12 @@ logNow s i = do
 {- Reads a log and returns only the info that is still in effect. -}
 currentLog :: FilePath -> Annex [String]
 currentLog file = map info . filterPresent <$> readLog file
+
+{- Reads a historical version of a log and returns the info that was in
+ - effect at that time. 
+ -
+ - The date is formatted as shown in gitrevisions man page.
+ -}
+historicalLog :: RefDate -> FilePath -> Annex [String]
+historicalLog refdate file = map info . filterPresent . parseLog
+	<$> Annex.Branch.getHistorical refdate file