[PATCH] difftool --dir-diff: copy back all files matching the working tree

[Kenichi Saita <nitoyon@gmail.com>]

After running the user's diff tool, "git difftool --dir-dif --no-symlink"
currently copied back a temporary file to working tree only when a file
contains unstaged changes in the working tree.

Change this behavior so that temporary files are copied back to working
tree whenever the right-hand side of the comparison has the same SHA1
as the file in the working tree.

Signed-off-by: Kenichi Saita <nitoyon@gmail.com>
---
 git-difftool.perl   |    9 ++-------
 t/t7800-difftool.sh |   19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/git-difftool.perl b/git-difftool.perl
index 8a75205..e57d3d1 100755
--- a/git-difftool.perl
+++ b/git-difftool.perl
@@ -85,13 +85,9 @@ sub exit_cleanup
 
 sub use_wt_file
 {
-	my ($repo, $workdir, $file, $sha1, $symlinks) = @_;
+	my ($repo, $workdir, $file, $sha1) = @_;
 	my $null_sha1 = '0' x 40;
 
-	if ($sha1 ne $null_sha1 and not $symlinks) {
-		return 0;
-	}
-
 	if (! -e "$workdir/$file") {
 		# If the file doesn't exist in the working tree, we cannot
 		# use it.
@@ -213,8 +209,7 @@ EOF
 
 		if ($rmode ne $null_mode) {
 			my ($use, $wt_sha1) = use_wt_file($repo, $workdir,
-							  $dst_path, $rsha1,
-							  $symlinks);
+							  $dst_path, $rsha1);
 			if ($use) {
 				push @working_tree, $dst_path;
 				$wtindex .= "$rmode $wt_sha1\t$dst_path\0";
diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index d46f041..2418528 100755
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -385,6 +385,25 @@ test_expect_success PERL,SYMLINKS 'difftool --dir-diff --symlink without unstage
 	test_cmp actual expect
 '
 
+write_script modify-right-file <<\EOF
+echo "new content" >"$2/file"
+EOF
+
+run_dir_diff_test 'difftool --dir-diff syncs worktree with unstaged change' '
+	test_when_finished git reset --hard &&
+	echo "orig content" >file &&
+	git difftool -d $symlinks --extcmd "$(pwd)/modify-right-file" branch &&
+	echo "new content" >expect &&
+	test_cmp expect file
+'
+
+run_dir_diff_test 'difftool --dir-diff syncs worktree without unstaged change' '
+	test_when_finished git reset --hard &&
+	git difftool -d $symlinks --extcmd "$(pwd)/modify-right-file" branch &&
+	echo "new content" >expect &&
+	test_cmp expect file
+'
+
 write_script modify-file <<\EOF
 echo "new content" >file
 EOF
-- 
1.7.1