Limit annex.largefiles parsing to the subset of preferred content expressions that make sense in its context.

So, not "standard" or "lackingcopies", etc.

6 files changed, 110 insertions, 64 deletions

diff --git a/Annex/FileMatcher.hs b/Annex/FileMatcher.hs
index e3482ec8b..b4a4b6d9a 100644
--- a/Annex/FileMatcher.hs
+++ b/Annex/FileMatcher.hs
@@ -5,7 +5,15 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
-module Annex.FileMatcher where
+module Annex.FileMatcher (
+	GetFileMatcher,
+	checkFileMatcher,
+	checkMatcher,
+	matchAll,
+	preferredContentParser,
+	parsedToMatcher,
+	largeFilesMatcher,
+) where
 
 import qualified Data.Map as M
 
@@ -13,8 +21,6 @@ import Annex.Common
 import Limit
 import Utility.Matcher
 import Types.Group
-import Logs.Group
-import Annex.UUID
 import qualified Annex
 import Types.FileMatcher
 import Git.FilePath
@@ -53,53 +59,38 @@ fileMatchInfo file = do
 matchAll :: FileMatcher Annex
 matchAll = generate []
 
-parsedToMatcher :: [Either String (Token (MatchFiles Annex))] -> Either String (FileMatcher Annex)
+parsedToMatcher :: [ParseResult] -> Either String (FileMatcher Annex)
 parsedToMatcher parsed = case partitionEithers parsed of
 	([], vs) -> Right $ generate vs
 	(es, _) -> Left $ unwords $ map ("Parse failure: " ++) es
 
-exprParser :: FileMatcher Annex -> FileMatcher Annex -> Annex GroupMap -> M.Map UUID RemoteConfig -> Maybe UUID -> String -> [Either String (Token (MatchFiles Annex))]
-exprParser matchstandard matchgroupwanted getgroupmap configmap mu expr =
-	map parse $ tokenizeMatcher expr
-  where
-	parse = parseToken
-		matchstandard
-		matchgroupwanted
-		(limitPresent mu)
-		(limitInDir preferreddir)
-		getgroupmap
-	preferreddir = fromMaybe "public" $
-		M.lookup "preferreddir" =<< (`M.lookup` configmap) =<< mu
+data ParseToken
+	= SimpleToken String ParseResult
+	| ValueToken String (String -> ParseResult)
 
-parseToken :: FileMatcher Annex -> FileMatcher Annex -> MatchFiles Annex -> MatchFiles Annex -> Annex GroupMap -> String -> Either String (Token (MatchFiles Annex))
-parseToken matchstandard matchgroupwanted checkpresent checkpreferreddir getgroupmap t
+type ParseResult = Either String (Token (MatchFiles Annex))
+
+parseToken :: [ParseToken] -> String -> ParseResult
+parseToken l t
 	| t `elem` tokens = Right $ token t
-	| otherwise = case t of
-		"standard" -> call matchstandard
-		"groupwanted" -> call matchgroupwanted
-		"present" -> simply checkpresent
-		"inpreferreddir" -> simply checkpreferreddir
-		"unused" -> simply limitUnused
-		"anything" -> simply limitAnything
-		"nothing" -> simply limitNothing
-		_ -> case k of
-			"include" -> usev limitInclude
-			"exclude" -> usev limitExclude
-			"copies" -> usev limitCopies
-			"lackingcopies" -> usev $ limitLackingCopies False
-			"approxlackingcopies" -> usev $ limitLackingCopies True
-			"inbackend" -> usev limitInBackend
-			"largerthan" -> usev $ limitSize (>)
-			"smallerthan" -> usev $ limitSize (<)
-			"metadata" -> usev limitMetaData
-			"inallgroup" -> usev $ limitInAllGroup getgroupmap
-			_ -> Left $ "near " ++ show t
+	| otherwise = go l
   where
+	go [] = Left $ "near " ++ show t
+	go (SimpleToken s r : _) | s == t = r
+	go (ValueToken s mkr : _) | s == k = mkr v
+	go (_ : ps) = go ps
 	(k, v) = separate (== '=') t
-	simply = Right . Operation
-	usev a = Operation <$> a v
-	call sub = Right $ Operation $ \notpresent mi ->
-		matchMrun sub $ \a -> a notpresent mi
+
+commonTokens :: [ParseToken]
+commonTokens =
+	[ SimpleToken "unused" (simply limitUnused)
+	, SimpleToken "anything" (simply limitAnything)
+	, SimpleToken "nothing" (simply limitNothing)
+	, ValueToken "include" (usev limitInclude)
+	, ValueToken "exclude" (usev limitExclude)
+	, ValueToken "largerthan" (usev $ limitSize (>))
+	, ValueToken "smallerthan" (usev $ limitSize (<))
+	]
 
 {- This is really dumb tokenization; there's no support for quoted values.
  - Open and close parens are always treated as standalone tokens;
@@ -109,6 +100,30 @@ tokenizeMatcher = filter (not . null ) . concatMap splitparens . words
   where
 	splitparens = segmentDelim (`elem` "()")
 
+preferredContentParser :: FileMatcher Annex -> FileMatcher Annex -> Annex GroupMap -> M.Map UUID RemoteConfig -> Maybe UUID -> String -> [ParseResult]
+preferredContentParser matchstandard matchgroupwanted getgroupmap configmap mu expr =
+	map parse $ tokenizeMatcher expr
+  where
+ 	parse = parseToken $
+		[ SimpleToken "standard" (call matchstandard)
+		, SimpleToken "groupwanted" (call matchgroupwanted)
+		, SimpleToken "present" (simply $ limitPresent mu)
+		, SimpleToken "inpreferreddir" (simply $ limitInDir preferreddir)
+		, ValueToken "copies" (usev limitCopies)
+		, ValueToken "lackingcopies" (usev $ limitLackingCopies False)
+		, ValueToken "approxlackingcopies" (usev $ limitLackingCopies True)
+		, ValueToken "inbacked" (usev limitInBackend)
+		, ValueToken "metadata" (usev limitMetaData)
+		, ValueToken "inallgroup" (usev $ limitInAllGroup getgroupmap)
+		] ++ commonTokens
+	preferreddir = fromMaybe "public" $
+		M.lookup "preferreddir" =<< (`M.lookup` configmap) =<< mu
+
+largeFilesParser :: String -> [ParseResult]
+largeFilesParser expr = map parse $ tokenizeMatcher expr
+  where
+	parse = parseToken commonTokens
+
 {- Generates a matcher for files large enough (or meeting other criteria)
  - to be added to the annex, rather than directly to git. -}
 largeFilesMatcher :: Annex GetFileMatcher
@@ -123,13 +138,15 @@ largeFilesMatcher = go =<< annexLargeFiles <$> Annex.getGitConfig
 			then return matchAll
 			else mkmatcher expr
 
-	mkmatcher expr = do
-		u <- getUUID
-		-- No need to read remote configs, that's only needed for
-		-- inpreferreddir, which is used in preferred content
-		-- expressions but does not make sense in the 
-		-- annex.largefiles expression.
-		let emptyconfig = M.empty
-		either badexpr return $
-			parsedToMatcher $ exprParser matchAll matchAll groupMap emptyconfig (Just u) expr
+	mkmatcher = either badexpr return . parsedToMatcher . largeFilesParser
 	badexpr e = error $ "bad annex.largefiles configuration: " ++ e
+
+simply :: MatchFiles Annex -> ParseResult
+simply = Right . Operation
+
+usev :: MkLimit Annex -> String -> ParseResult
+usev a v = Operation <$> a v
+
+call :: FileMatcher Annex -> ParseResult
+call sub = Right $ Operation $ \notpresent mi ->
+	matchMrun sub $ \a -> a notpresent mi
diff --git a/Command/MatchExpression.hs b/Command/MatchExpression.hs
index 062a46b55..a75101dce 100644
--- a/Command/MatchExpression.hs
+++ b/Command/MatchExpression.hs
@@ -60,7 +60,7 @@ optParser desc = MatchExpressionOptions
 seek :: MatchExpressionOptions -> CommandSeek
 seek o = do
 	u <- getUUID
-	case parsedToMatcher $ exprParser matchAll matchAll groupMap M.empty (Just u) (matchexpr o) of
+	case parsedToMatcher $ preferredContentParser matchAll matchAll groupMap M.empty (Just u) (matchexpr o) of
 		Left e -> liftIO $ bail $ "bad expression: " ++ e
 		Right matcher -> ifM (checkmatcher matcher)
 			( liftIO exitSuccess
diff --git a/Logs/PreferredContent.hs b/Logs/PreferredContent.hs
index a74effb92..d84abbaba 100644
--- a/Logs/PreferredContent.hs
+++ b/Logs/PreferredContent.hs
@@ -102,7 +102,7 @@ makeMatcher groupmap configmap groupwantedmap u = go True True
 		| null (lefts tokens) = generate $ rights tokens
 		| otherwise = unknownMatcher u
 	  where
-		tokens = exprParser matchstandard matchgroupwanted (pure groupmap) configmap (Just u) expr
+		tokens = preferredContentParser matchstandard matchgroupwanted (pure groupmap) configmap (Just u) expr
 		matchstandard
 			| expandstandard = maybe (unknownMatcher u) (go False False)
 				(standardPreferredContent <$> getStandardGroup mygroups)
@@ -133,7 +133,7 @@ checkPreferredContentExpression expr = case parsedToMatcher tokens of
 	Left e -> Just e
 	Right _ -> Nothing
   where
-	tokens = exprParser matchAll matchAll (pure emptyGroupMap) M.empty Nothing expr
+	tokens = preferredContentParser matchAll matchAll (pure emptyGroupMap) M.empty Nothing expr
 
 {- Puts a UUID in a standard group, and sets its preferred content to use
  - the standard expression for that group (unless preferred content is
diff --git a/debian/changelog b/debian/changelog
index a834e3de1..6b4373af6 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -10,6 +10,9 @@ git-annex (6.20160127) UNRELEASED; urgency=medium
     this is particulary useful for v6 repositories, since the
     .gitattributes configuration will apply in all clones of the
     repository.
+  * Limit annex.largefiles parsing to the subset of preferred content
+    expressions that make sense in its context. So, not "standard"
+    or "lackingcopies", etc.
 
  -- Joey Hess <id@joeyh.name>  Thu, 28 Jan 2016 13:53:09 -0400
 
diff --git a/doc/git-annex-preferred-content.mdwn b/doc/git-annex-preferred-content.mdwn
index c8c5d06af..bea82654f 100644
--- a/doc/git-annex-preferred-content.mdwn
+++ b/doc/git-annex-preferred-content.mdwn
@@ -32,7 +32,7 @@ elsewhere to allow removing it).
 
 # EXPRESSIONS
 
-* `include=glob` and `exclude=glob`
+* `include=glob` / `exclude=glob`
 
   Match files to include, or exclude.
 
@@ -101,7 +101,7 @@ elsewhere to allow removing it).
   Matches only files that git-annex believes are present in all repositories
   in the specified group.
 
-* `smallerthan=size` and `largerthan=size`
+* `smallerthan=size` / `largerthan=size`
 
   Matches only files whose content is smaller than, or larger than the
   specified size.
diff --git a/doc/tips/largefiles.mdwn b/doc/tips/largefiles.mdwn
index ec51ecf66..c07d7f3f2 100644
--- a/doc/tips/largefiles.mdwn
+++ b/doc/tips/largefiles.mdwn
@@ -42,19 +42,45 @@ checkouts behave differently. The git configuration overrides the
 
 ## syntax
 
+The value of annex.largefiles is similar to a
+[[preferred content expression|git-annex-preferred-content]].
+The following terms can be used in annex.largefiles:
+
+* `include=glob` / `exclude=glob`
+
+  Specify files to include or exclude.
+
+* `smallerthan=size` / `largerthan=size`
+
+  Matches only files smaller than, or larger than the specified size.
+
+  The size can be specified with any commonly used units, for example,
+  "0.5 gb" or "100 KiloBytes"
+
+* `anything`
+
+  Matches any file.
+
+* `nothing`
+
+  Matches no files. (Same as "not anything")
+
+* `not expression`
+
+  Inverts what the expression matches.
+
+* `and` / `or` / `( expression )`
+
+  These can be used to build up more complicated expressions.
+
 The way the `.gitattributes` example above works is, `*.c` and `*.h` files
-have the annex.largefiles attribute set to "nothing", which matches nothing,
+have the annex.largefiles attribute set to "nothing",
 and so those files are never treated as large files. All other files use
 the other value, which checks the file size.
 
-The value of annex.largefiles is a
-[[preferred content expression|git-annex-preferred-content]] that is
-used to match the large files.
-
 Note that, since git attribute values cannot contain whitespace,
-it's useful to instead parenthesize the terms of the 
-[[preferred content expression|git-annex-preferred-content]]. This trick
-allows setting the annex.largefiles attribute to more complicated expressions.
+it's useful to instead parenthesize the terms of the annex.largefiles
+attribute. This trick allows for more complicated expressions.
 For example, this is the same as the git config shown earlier, shoehorned
 into a git attribute: