git-ls-files: add --exclude-standard

This provides a way for scripts to get at the new standard exclude
function.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-ls-files.txt

@@ -15,6 +15,7 @@ SYNOPSIS
 		[-x <pattern>|--exclude=<pattern>]
 		[-X <file>|--exclude-from=<file>]
 		[--exclude-per-directory=<file>]
+		[--exclude-standard]
 		[--error-unmatch] [--with-tree=<tree-ish>]
 		[--full-name] [--abbrev] [--] [<file>]\*
 
@@ -77,6 +78,10 @@ OPTIONS
 	read additional exclude patterns that apply only to the
 	directory and its subdirectories in <file>.
 
+--exclude-standard::
+	Add the standard git exclusions: .git/info/exclude, .gitignore
+	in each directory, and the user's global exclusion file.
+
 --error-unmatch::
 	If any <file> does not appear in the index, treat this as an
 	error (return 1).

builtin-ls-files.c

@@ -387,8 +387,8 @@ static void overlay_tree(const char *tree_name, const char *prefix)
 static const char ls_files_usage[] =
 	"git-ls-files [-z] [-t] [-v] (--[cached|deleted|others|stage|unmerged|killed|modified])* "
 	"[ --ignored ] [--exclude=<pattern>] [--exclude-from=<file>] "
-	"[ --exclude-per-directory=<filename> ] [--full-name] [--abbrev] "
-	"[--] [<file>]*";
+	"[ --exclude-per-directory=<filename> ] [--exclude-standard] "
+	"[--full-name] [--abbrev] [--] [<file>]*";
 
 int cmd_ls_files(int argc, const char **argv, const char *prefix)
 {
@@ -496,6 +496,11 @@ int cmd_ls_files(int argc, const char **argv, const char *prefix)
 			dir.exclude_per_dir = arg + 24;
 			continue;
 		}
+		if (!strcmp(arg, "--exclude-standard")) {
+			exc_given = 1;
+			setup_standard_excludes(&dir);
+			continue;
+		}
 		if (!strcmp(arg, "--full-name")) {
 			prefix_offset = 0;
 			continue;

git-add--interactive.perl

@@ -37,10 +37,7 @@ sub list_untracked {
 		chomp $_;
 		$_;
 	}
-	run_cmd_pipe(qw(git ls-files --others
-			--exclude-per-directory=.gitignore),
-		     "--exclude-from=$GIT_DIR/info/exclude",
-		     '--', @_);
+	run_cmd_pipe(qw(git ls-files --others --exclude-standard --), @_);
 }
 
 my $status_fmt = '%12s %12s %s';