add git config lookups for annex.name, annex.backends, etc

1 files changed, 18 insertions, 0 deletions

diff --git a/BackendList.hs b/BackendList.hs
index c744949b6..77e4bd817 100644
--- a/BackendList.hs
+++ b/BackendList.hs
@@ -4,6 +4,7 @@
 module BackendList where
 
 -- When adding a new backend, import it here and add it to the list.
+import Types
 import qualified BackendFile
 import qualified BackendChecksum
 import qualified BackendUrl
@@ -12,3 +13,20 @@ supportedBackends =
 	, BackendChecksum.backend
 	, BackendUrl.backend
 	]
+
+{- Parses a string with a list of backend names into
+ - a list of Backend objects. If the list is empty,
+ - defaults to supportedBackends. -}
+parseBackendList :: String -> [Backend]
+parseBackendList s = 
+	if (length s == 0)
+		then supportedBackends
+		else map (lookupBackendName) $ words s
+
+{- Looks up a supported backed by name. -}
+lookupBackendName :: String -> Backend
+lookupBackendName s =
+	if ((length matches) /= 1)
+		then error $ "unknown backend " ++ s
+		else matches !! 0
+	where matches = filter (\b -> s == name b) supportedBackends