For consistency with 'got branch', switch 'got tag tagname commit' to
'got tag -c commit tagname'.

ok?

diff 212b39d173639f6f9aab137db52b888d5e1022ec /home/stsp/src/got
blob - b255255c35b0599f3ce3cfba03065a17637afdea
file + got/got.1
--- got/got.1
+++ got/got.1
@@ -587,7 +587,7 @@ Git's garbage collector.
 .It Cm br
 Short alias for
 .Cm branch .
-.It Cm tag Oo Fl m Ar message Oc Oo Fl r Ar repository-path Oc Oo Fl l Oc Ar name Op Ar commit
+.It Cm tag Oo Fl c Ar commit Oc Oo Fl m Ar message Oc Oo Fl r Ar repository-path Oc Oo Fl l Oc Ar name
 Manage tags in a repository.
 .Pp
 Tags are managed via references which live in the
@@ -599,24 +599,29 @@ command operates on references in this namespace only.
 References in this namespace point at tag objects which contain a pointer
 to another object, a tag message, as well as author and timestamp information.
 .Pp
-Expect one or two arguments and attempt to create a tag with the given
+Attempt to create a tag with the given
 .Ar name ,
 and make this tag point at the given
 .Ar commit .
 If no commit is specified, default to the latest commit on the work tree's
 current branch if invoked in a work tree, and to a commit resolved via
 the repository's HEAD reference otherwise.
-Otherwise, the expected argument is a commit ID SHA1 hash or an existing
-reference or tag name which will be resolved to a commit ID.
-An abbreviated hash argument will be expanded to a full SHA1 hash
-automatically, provided the abbreviation is unique.
 .Pp
 The options for
 .Cm got tag
 are as follows:
 .Bl -tag -width Ds
+.It Fl c Ar commit
+Make the newly created tag reference point at the specified
+.Ar commit .
+The expected
+.Ar commit
+argument is a commit ID SHA1 hash or an existing reference or tag name which
+will be resolved to a commit ID.
+An abbreviated hash argument will be expanded to a full SHA1 hash
+automatically, provided the abbreviation is unique.
 .It Fl m Ar message
-Use the specified tag message when creating the new tag
+Use the specified tag message when creating the new tag.
 Without the
 .Fl m
 option,
blob - 7a50d3a7ec56e05bab9576a9e6d61188b261f9a5
file + got/got.c
--- got/got.c
+++ got/got.c
@@ -3597,8 +3597,8 @@ __dead static void
 usage_tag(void)
 {
 	fprintf(stderr,
-	    "usage: %s tag [-r repository] | -l | "
-	        "[-m message] name [commit]\n", getprogname());
+	    "usage: %s tag [-c commit] [-r repository] [-l] "
+	        "[-m message] name\n", getprogname());
 	exit(1);
 }
 
@@ -3949,8 +3949,11 @@ cmd_tag(int argc, char *argv[])
 	const char *tag_name, *commit_id_arg = NULL, *tagmsg = NULL;
 	int ch, do_list = 0;
 
-	while ((ch = getopt(argc, argv, "m:r:l")) != -1) {
+	while ((ch = getopt(argc, argv, "c:m:r:l")) != -1) {
 		switch (ch) {
+		case 'c':
+			commit_id_arg = optarg;
+			break;
 		case 'm':
 			tagmsg = optarg;
 			break;
@@ -3974,14 +3977,15 @@ cmd_tag(int argc, char *argv[])
 	argv += optind;
 
 	if (do_list) {
+		if (commit_id_arg != NULL)
+			errx(1, "-c option can only be used when creating a tag");
 		if (tagmsg)
-			errx(1, "-l and -m options are mutually exclusive\n");
+			errx(1, "-l and -m options are mutually exclusive");
 		if (argc > 0)
 			usage_tag();
-	} else if (argc < 1 || argc > 2)
+	} else if (argc != 1)
 		usage_tag();
-	else if (argc > 1)
-		commit_id_arg = argv[1];
+
 	tag_name = argv[0];
 
 #ifndef PROFILE
blob - 4fe82be2ade02d326fa45a5b99005bf6bda52252
file + regress/cmdline/tag.sh
--- regress/cmdline/tag.sh
+++ regress/cmdline/tag.sh
@@ -23,7 +23,7 @@ function test_tag_create {
 	local tag2=2.0.0
 
 	# Create a tag based on repository's HEAD reference
-	got tag -m 'test' -r $testroot/repo $tag HEAD > $testroot/stdout
+	got tag -m 'test' -r $testroot/repo -c HEAD $tag > $testroot/stdout
 	ret="$?"
 	if [ "$ret" != "0" ]; then
 		echo "got ref command failed unexpectedly"
@@ -88,7 +88,7 @@ function test_tag_create {
 
 	# Attempt to create a tag pointing at a non-commit
 	local tree_id=`git_show_tree $testroot/repo`
-	(cd $testroot/wt && got tag -m 'test' foobar $tree_id \
+	(cd $testroot/wt && got tag -m 'test' -c $tree_id foobar \
 		2> $testroot/stderr)
 	ret="$?"
 	if [ "$ret" == "0" ]; then