Merge branch 'ms/ls-remote-exit-with-status'

* ms/ls-remote-exit-with-status:
  ls-remote: the --exit-code option reports "no matching refs"

Documentation/git-ls-remote.txt

@@ -10,7 +10,7 @@ SYNOPSIS
 --------
 [verse]
 'git ls-remote' [--heads] [--tags]  [-u <exec> | --upload-pack <exec>]
-	      <repository> [<refs>...]
+	      [--exit-code] <repository> [<refs>...]
 
 DESCRIPTION
 -----------
@@ -36,6 +36,12 @@ OPTIONS
 	SSH and where the SSH daemon does not use the PATH configured by the
 	user.
 
+--exit-code::
+	Exit with status "2" when no matching refs are found in the remote
+	repository. Usually the command exits with status "0" to indicate
+	it successfully talked with the remote repository, whether it
+	found any matching refs.
+
 <repository>::
 	Location of the repository.  The shorthand defined in
 	$GIT_DIR/branches/ can be used. Use "." (dot) to list references in

builtin/ls-remote.c

@@ -5,7 +5,7 @@
 
 static const char ls_remote_usage[] =
 "git ls-remote [--heads] [--tags]  [-u <exec> | --upload-pack <exec>]\n"
-"                     [-q|--quiet] [<repository> [<refs>...]]";
+"                     [-q|--quiet] [--exit-code] [<repository> [<refs>...]]";
 
 /*
  * Is there one among the list of patterns that match the tail part
@@ -35,6 +35,7 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
 	unsigned flags = 0;
 	int get_url = 0;
 	int quiet = 0;
+	int status = 0;
 	const char *uploadpack = NULL;
 	const char **pattern = NULL;
 
@@ -74,6 +75,11 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
 				get_url = 1;
 				continue;
 			}
+			if (!strcmp("--exit-code", arg)) {
+				/* return this code if no refs are reported */
+				status = 2;
+				continue;
+			}
 			usage(ls_remote_usage);
 		}
 		dest = arg;
@@ -121,6 +127,7 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
 		if (!tail_match(pattern, ref->name))
 			continue;
 		printf("%s	%s\n", sha1_to_hex(ref->old_sha1), ref->name);
+		status = 0; /* we found something */
 	}
-	return 0;
+	return status;
 }

t/t5512-ls-remote.sh

@@ -123,4 +123,28 @@ test_expect_success 'confuses pattern as remote when no remote specified' '
 
 '
 
+test_expect_success 'die with non-2 for wrong repository even with --exit-code' '
+	git ls-remote --exit-code ./no-such-repository ;# not &&
+	status=$? &&
+	test $status != 2 && test $status != 0
+'
+
+test_expect_success 'Report success even when nothing matches' '
+	git ls-remote other.git "refs/nsn/*" >actual &&
+	>expect &&
+	test_cmp expect actual
+'
+
+test_expect_success 'Report no-match with --exit-code' '
+	test_expect_code 2 git ls-remote --exit-code other.git "refs/nsn/*" >actual &&
+	>expect &&
+	test_cmp expect actual
+'
+
+test_expect_success 'Report match with --exit-code' '
+	git ls-remote --exit-code other.git "refs/tags/*" >actual &&
+	git ls-remote . tags/mark >expect &&
+	test_cmp expect actual
+'
+
 test_done