locking: remove write permission for ignored files

When a file exists in a user's working copy that has been previously
marked as lockable and has since become ignored, the file's write
permission would no longer be managed by Git LFS.

Since 'git lfs lock' corresponds to pathname only (and thus is not
affected by Git-specific concepts such as .gitignore), let's continue to
manage those files' write permissions by using tools.FastWalkGitRepoAll
instead of tools.FastWalkGitRepo.

locking/lockable.go

@@ -122,7 +122,7 @@ func (c *Client) fixFileWriteFlags(absPath, workingDir string, lockable, unlocka
 		errs = append(errs, err)
 	}
 
-	tools.FastWalkGitRepo(absPath, func(parentDir string, fi os.FileInfo, err error) {
+	tools.FastWalkGitRepoAll(absPath, func(parentDir string, fi os.FileInfo, err error) {
 		if err != nil {
 			addErr(err)
 			return

t/t-lock.sh

@@ -229,3 +229,27 @@ begin_test "creating a lock (symlinked working directory)"
   popd > /dev/null
 )
 end_test
+
+begin_test "lock with .gitignore"
+(
+  set -e
+
+  reponame="lock-with-gitignore"
+  setup_remote_repo_with_file "$reponame" "a.txt"
+  clone_repo "$reponame" "$reponame"
+
+  echo "*.txt filter=lfs diff=lfs merge=lfs -text lockable" > .gitattributes
+
+  git add .gitattributes
+  git commit -m ".gitattributes: mark 'a.txt' as lockable"
+
+  rm -f a.txt && git checkout a.txt
+  refute_file_writeable a.txt
+
+  echo "*.txt" > .gitignore
+  git add .gitignore
+  git commit -m ".gitignore: ignore 'a.txt'"
+  rm -f a.txt && git checkout a.txt
+  refute_file_writeable a.txt
+)
+end_test