+ my $use = ($sha1 eq $null_sha1) || ($sha1 eq $wt_sha1);
+ return ($use, $wt_sha1);
+}
+
+sub changed_files
+{
+ my ($repo_path, $index, $worktree) = @_;
+ $ENV{GIT_INDEX_FILE} = $index;
+ $ENV{GIT_WORK_TREE} = $worktree;
+ my $must_unset_git_dir = 0;
+ if (not defined($ENV{GIT_DIR})) {
+ $must_unset_git_dir = 1;
+ $ENV{GIT_DIR} = $repo_path;
+ }
+
+ my @refreshargs = qw/update-index --really-refresh -q --unmerged/;
+ my @gitargs = qw/diff-files --name-only -z/;
+ try {
+ Git::command_oneline(@refreshargs);
+ } catch Git::Error::Command with {};
+
+ my $line = Git::command_oneline(@gitargs);
+ my @files;
+ if (defined $line) {
+ @files = split('\0', $line);
+ } else {
+ @files = ();
+ }
+
+ delete($ENV{GIT_INDEX_FILE});
+ delete($ENV{GIT_WORK_TREE});
+ delete($ENV{GIT_DIR}) if ($must_unset_git_dir);
+
+ return map { $_ => 1 } @files;