"git tag -u keyname" broken

Commit 3968658 broke signed tags using
the "-u" flag when it made builtin-tag.c use parse_options() to parse its
arguments (but it quite possibly was broken even before that, by the
builtin rewrite).

It used to be that passing the signing ID with the -u parameter also
(obviously!) implied that you wanted to sign and annotate the tag, but
that logic got dropped. It also totally ignored the actual key ID that was
passed in.

This reinstates it all.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-tag.c

@@ -236,14 +236,18 @@ static const char tag_template[] =
 	"# Write a tag message\n"
 	"#\n";
 
+static void set_signingkey(const char *value)
+{
+	if (strlcpy(signingkey, value, sizeof(signingkey)) >= sizeof(signingkey))
+		die("signing key value too long (%.10s...)", value);
+}
+
 static int git_tag_config(const char *var, const char *value)
 {
 	if (!strcmp(var, "user.signingkey")) {
 		if (!value)
 			die("user.signingkey without value");
-		if (strlcpy(signingkey, value, sizeof(signingkey))
-						>= sizeof(signingkey))
-			die("user.signingkey value too long");
+		set_signingkey(value);
 		return 0;
 	}
 
@@ -396,6 +400,10 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 
 	argc = parse_options(argc, argv, options, git_tag_usage, 0);
 
+	if (keyid) {
+		sign = 1;
+		set_signingkey(keyid);
+	}
 	if (sign)
 		annotate = 1;
 

t/t7004-tag.sh

@@ -640,6 +640,46 @@ test_expect_success 'creating a signed tag with -m message should succeed' '
 	git diff expect actual
 '
 
+get_tag_header u-signed-tag $commit commit $time >expect
+echo 'Another message' >>expect
+echo '-----BEGIN PGP SIGNATURE-----' >>expect
+test_expect_success 'sign with a given key id' '
+
+	git tag -u committer@example.com -m "Another message" u-signed-tag &&
+	get_tag_msg u-signed-tag >actual &&
+	git diff expect actual
+
+'
+
+test_expect_success 'sign with an unknown id (1)' '
+
+	! git tag -u author@example.com -m "Another message" o-signed-tag
+
+'
+
+test_expect_success 'sign with an unknown id (2)' '
+
+	! git tag -u DEADBEEF -m "Another message" o-signed-tag
+
+'
+
+cat >fakeeditor <<'EOF'
+#!/bin/sh
+test -n "$1" && exec >"$1"
+echo A signed tag message
+echo from a fake editor.
+EOF
+chmod +x fakeeditor
+
+get_tag_header implied-sign $commit commit $time >expect
+./fakeeditor >>expect
+echo '-----BEGIN PGP SIGNATURE-----' >>expect
+test_expect_success '-u implies signed tag' '
+	GIT_EDITOR=./fakeeditor git-tag -u CDDE430D implied-sign &&
+	get_tag_msg implied-sign >actual &&
+	git diff expect actual
+'
+
 cat >sigmsgfile <<EOF
 Another signed tag
 message in a file.
@@ -667,13 +707,6 @@ test_expect_success 'creating a signed tag with -F - should succeed' '
 	git diff expect actual
 '
 
-cat >fakeeditor <<'EOF'
-#!/bin/sh
-test -n "$1" && exec >"$1"
-echo A signed tag message
-echo from a fake editor.
-EOF
-chmod +x fakeeditor
 get_tag_header implied-annotate $commit commit $time >expect
 ./fakeeditor >>expect
 echo '-----BEGIN PGP SIGNATURE-----' >>expect