avoid uncessary call to inAnnex

sync --content: Avoid a redundant checksum of a file that was
incrementally verified, when used on NTFS and perhaps other filesystems.

When sync has just gotten the content, it does not need to check inAnnex a
second time. On NTFS, for some reason the write of the inode cache after
it gets the content is not immediately able to be read, and with an
empty/non-matching inode cache due to that stale data, inAnnex falls back
to hashing the whole object to determine if it's present.

Sponsored-by: Brock Spratlen on Patreon

CHANGELOG

@@ -11,6 +11,8 @@ git-annex (8.20210904) UNRELEASED; urgency=medium
   * Sped up git-annex smudge --clean by 25%.
   * Resume where it left off when copying a file to/from a local git remote
     was interrupted.
+  * sync --content: Avoid a redundant checksum of a file that was
+    incrementally verified, when used on NTFS and perhaps other filesystems.
 
  -- Joey Hess <id@joeyh.name>  Fri, 03 Sep 2021 12:02:55 -0400
 

Command/Sync.hs

@@ -809,10 +809,11 @@ syncFile ebloom rs af k = do
 	let (have, lack) = partition (\r -> Remote.uuid r `elem` locs) rs
 
 	got <- anyM id =<< handleget have inhere
-	putrs <- handleput lack
+	let inhere' = inhere || got
+	putrs <- handleput lack inhere'
 
 	u <- getUUID
-	let locs' = concat [if inhere || got then [u] else [], putrs, locs]
+	let locs' = concat [if inhere' then [u] else [], putrs, locs]
 
 	-- To handle --all, a bloom filter is populated with all the keys
 	-- of files in the working tree in the first pass. On the second
@@ -855,14 +856,15 @@ syncFile ebloom rs af k = do
 		| Remote.readonly r || remoteAnnexReadOnly (Remote.gitconfig r) = return False
 		| isThirdPartyPopulated r = return False
 		| otherwise = wantSend True (Just k) af (Remote.uuid r)
-	handleput lack = catMaybes <$> ifM (inAnnex k)
+	handleput lack inhere
+		| inhere = catMaybes <$>
 			( forM lack $ \r ->
 				ifM (wantput r <&&> put r)
 					( return (Just (Remote.uuid r))
 					, return Nothing
 					)
-		, return []
 			)
+		| otherwise = return []
 	put dest = includeCommandAction $ 
 		Command.Move.toStart' dest Command.Move.RemoveNever af k ai si
 

doc/bugs/__96__sync_-C__96___takes_longer_to_get_file_than___96__get__96__.mdwn

@@ -724,3 +724,5 @@ from 159 to 296985).
 Git Annex is great. It works quite nicely with my multi-gigabyte backup files (largest around 180GB) via the BLAKE2B160E backend :)
 
 [[!meta title="windows: sync -C takes longer than get, apparently extra checksum"]] 
+
+> [[fixed|done]] --[[Joey]]

doc/bugs/__96__sync_-C__96___takes_longer_to_get_file_than___96__get__96__/comment_11_d485bbc1c0f2fceaaa2e4142dccdc1f7._comment

@@ -0,0 +1,17 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 11"""
+ date="2021-10-01T15:57:12Z"
+ content="""
+Fixed by avoiding sync calling inAnnex when it knows it has the content,
+because it just got it.
+
+This does leave open the possibility that there are similar situations
+elsewhere, that lead to either extra work like this, or to incorrect
+behavior. Since sqlite write followed by a read is generally something
+git-annex is careful of, and also since it is generally careful to have
+reasonable behavior is sqlite somehow loses data, I'm not too worried about
+incorrect behavior. I feel comfortable closing this bug with just this fix,
+despite not getting to the bottom of the issue of why sqlite writes are
+not immediately able to be read back on NTFS.
+"""]]