teach "git branch" a --quiet option

There's currently no way to suppress the informational
"deleted branch..." or "set up tracking..." messages.  This
patch provides a "-q" option to do so.

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

Documentation/git-branch.txt

@@ -126,6 +126,11 @@ OPTIONS
 	relationship to upstream branch (if any). If given twice, print
 	the name of the upstream branch, as well.
 
+-q::
+--quiet::
+	Be more quiet when creating or deleting a branch, suppressing
+	non-error messages.
+
 --abbrev=<length>::
 	Alter the sha1's minimum display length in the output listing.
 	The default value is 7 and can be overridden by the `core.abbrev`

builtin/branch.c

@@ -146,7 +146,8 @@ static int branch_merged(int kind, const char *name,
 	return merged;
 }
 
-static int delete_branches(int argc, const char **argv, int force, int kinds)
+static int delete_branches(int argc, const char **argv, int force, int kinds,
+			   int quiet)
 {
 	struct commit *rev, *head_rev = NULL;
 	unsigned char sha1[20];
@@ -216,9 +217,10 @@ static int delete_branches(int argc, const char **argv, int force, int kinds)
 			ret = 1;
 		} else {
 			struct strbuf buf = STRBUF_INIT;
-			printf(_("Deleted %sbranch %s (was %s).\n"), remote,
-			       bname.buf,
-			       find_unique_abbrev(sha1, DEFAULT_ABBREV));
+			if (!quiet)
+				printf(_("Deleted %sbranch %s (was %s).\n"),
+				       remote, bname.buf,
+				       find_unique_abbrev(sha1, DEFAULT_ABBREV));
 			strbuf_addf(&buf, "branch.%s", bname.buf);
 			if (git_config_rename_section(buf.buf, NULL) < 0)
 				warning(_("Update of config-file failed"));
@@ -678,6 +680,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	int delete = 0, rename = 0, force_create = 0, list = 0;
 	int verbose = 0, abbrev = -1, detached = 0;
 	int reflog = 0, edit_description = 0;
+	int quiet = 0;
 	enum branch_track track;
 	int kinds = REF_LOCAL_BRANCH;
 	struct commit_list *with_commit = NULL;
@@ -686,6 +689,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		OPT_GROUP("Generic options"),
 		OPT__VERBOSE(&verbose,
 			"show hash and subject, give twice for upstream branch"),
+		OPT__QUIET(&quiet, "suppress informational messages"),
 		OPT_SET_INT('t', "track",  &track, "set up tracking mode (see git-pull(1))",
 			BRANCH_TRACK_EXPLICIT),
 		OPT_SET_INT( 0, "set-upstream",  &track, "change upstream info",
@@ -766,7 +770,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		abbrev = DEFAULT_ABBREV;
 
 	if (delete)
-		return delete_branches(argc, argv, delete > 1, kinds);
+		return delete_branches(argc, argv, delete > 1, kinds, quiet);
 	else if (list)
 		return print_ref_list(kinds, detached, verbose, abbrev,
 				      with_commit, argv);
@@ -808,7 +812,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		if (kinds != REF_LOCAL_BRANCH)
 			die(_("-a and -r options to 'git branch' do not make sense with a branch name"));
 		create_branch(head, argv[0], (argc == 2) ? argv[1] : head,
-			      force_create, reflog, 0, 0, track);
+			      force_create, reflog, 0, quiet, track);
 	} else
 		usage_with_options(builtin_branch_usage, options);