pre-commit: Update metadata when committing changes to annexed files within a view.

So the user can now switch to a view and then move files around within it
to manage metadata. For example, moving a file into a new directory
when in the tags=* view adds a tag to it.

Implementation is fairly efficient. One diff-index, which is no more
expensive than the first stage of a git commit, followed by possibly
some cat-file --batch traffic to find the key (when deleting a file).
Very similar to what's done in direct mode when committing. And like
direct mode when updating the WC after a merge, it has to buffer the
diff-tree values in order to make 2 passes over them.

When not in a view, pre-commit now does one extra git symbolic-ref,
which is tiny overhead.

This commit was sponsored by Andrew Eskridge.
This commit is contained in:
Joey Hess 2014-02-19 14:14:44 -04:00
parent 02259d2a55
commit 39ebfa1a2e
6 changed files with 103 additions and 23 deletions

View file

@ -28,8 +28,6 @@
module Logs.MetaData (
getCurrentMetaData,
getMetaData,
setMetaData,
unsetMetaData,
addMetaData,
addMetaData',
currentMetaData,
@ -58,16 +56,6 @@ getCurrentMetaData = currentMetaData . collect <$$> getMetaData
where
collect = foldl' unionMetaData newMetaData . map value . S.toAscList
setMetaData :: Key -> MetaField -> String -> Annex ()
setMetaData = setMetaData' True
unsetMetaData :: Key -> MetaField -> String -> Annex ()
unsetMetaData = setMetaData' False
setMetaData' :: Bool -> Key -> MetaField -> String -> Annex ()
setMetaData' isset k field s = addMetaData k $
updateMetaData field (mkMetaValue (CurrentlySet isset) s) newMetaData
{- Adds in some metadata, which can override existing values, or unset
- them, but otherwise leaves any existing metadata as-is. -}
addMetaData :: Key -> MetaData -> Annex ()