Merge branch 'dl/warn-tagging-a-tag'

gitster · gitster · commit a19856234152 · 2019-05-09T00:37:22.000+09:00
"git tag" learned to give an advice suggesting it might be a
mistake when creating an annotated or signed tag that points at
another tag.

* dl/warn-tagging-a-tag:
  tag: advise on nested tags
  tag: fix formatting
diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
@@ -90,4 +90,6 @@ advice.*::
 	waitingForEditor::
 		Print a message to the terminal whenever Git is waiting for
 		editor input from the user.
+	nestedTag::
+		Advice shown if a user attempts to recursively tag a tag object.
 --
diff --git a/advice.c b/advice.c
@@ -26,6 +26,7 @@ int advice_ignored_hook = 1;
 int advice_waiting_for_editor = 1;
 int advice_graft_file_deprecated = 1;
 int advice_checkout_ambiguous_remote_branch_name = 1;
+int advice_nested_tag = 1;
 
 static int advice_use_color = -1;
 static char advice_colors[][COLOR_MAXLEN] = {
@@ -81,6 +82,7 @@ static struct {
 	{ "waitingForEditor", &advice_waiting_for_editor },
 	{ "graftFileDeprecated", &advice_graft_file_deprecated },
 	{ "checkoutAmbiguousRemoteBranchName", &advice_checkout_ambiguous_remote_branch_name },
+	{ "nestedTag", &advice_nested_tag },
 
 	/* make this an alias for backward compatibility */
 	{ "pushNonFastForward", &advice_push_update_rejected }
diff --git a/advice.h b/advice.h
@@ -26,6 +26,7 @@ extern int advice_ignored_hook;
 extern int advice_waiting_for_editor;
 extern int advice_graft_file_deprecated;
 extern int advice_checkout_ambiguous_remote_branch_name;
+extern int advice_nested_tag;
 
 int git_default_advice_config(const char *var, const char *value);
 __attribute__((format (printf, 1, 2)))
diff --git a/builtin/tag.c b/builtin/tag.c
@@ -22,10 +22,11 @@
 #include "ref-filter.h"
 
 static const char * const git_tag_usage[] = {
-	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
+	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>]\n"
+		"\t\t<tagname> [<head>]"),
 	N_("git tag -d <tagname>..."),
-	N_("git tag -l [-n[<num>]] [--contains <commit>] [--no-contains <commit>] [--points-at <object>]"
-		"\n\t\t[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]"),
+	N_("git tag -l [-n[<num>]] [--contains <commit>] [--no-contains <commit>] [--points-at <object>]\n"
+		"\t\t[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]"),
 	N_("git tag -v [--format=<format>] <tagname>..."),
 	NULL
 };
@@ -205,7 +206,14 @@ struct create_tag_options {
 	} cleanup_mode;
 };
 
-static void create_tag(const struct object_id *object, const char *tag,
+static const char message_advice_nested_tag[] =
+	N_("You have created a nested tag. The object referred to by your new is\n"
+	   "already a tag. If you meant to tag the object that it points to, use:\n"
+	   "\n"
+	   "\tgit tag -f %s %s^{}");
+
+static void create_tag(const struct object_id *object, const char *object_ref,
+		       const char *tag,
 		       struct strbuf *buf, struct create_tag_options *opt,
 		       struct object_id *prev, struct object_id *result)
 {
@@ -215,7 +223,10 @@ static void create_tag(const struct object_id *object, const char *tag,
 
 	type = oid_object_info(the_repository, object, NULL);
 	if (type <= OBJ_NONE)
-	    die(_("bad object type."));
+		die(_("bad object type."));
+
+	if (type == OBJ_TAG && advice_nested_tag)
+		advise(_(message_advice_nested_tag), tag, object_ref);
 
 	strbuf_addf(&header,
 		    "object %s\n"
@@ -549,7 +560,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	if (create_tag_object) {
 		if (force_sign_annotate && !annotate)
 			opt.sign = 1;
-		create_tag(&object, tag, &buf, &opt, &prev, &object);
+		create_tag(&object, object_ref, tag, &buf, &opt, &prev, &object);
 	}
 
 	transaction = ref_transaction_begin(&err);
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
@@ -1700,6 +1700,17 @@ test_expect_success '--points-at finds annotated tags of tags' '
 	test_cmp expect actual
 '
 
+test_expect_success 'recursive tagging should give advice' '
+	sed -e "s/|$//" <<-EOF >expect &&
+	hint: You have created a nested tag. The object referred to by your new is
+	hint: already a tag. If you meant to tag the object that it points to, use:
+	hint: |
+	hint: 	git tag -f nested annotated-v4.0^{}
+	EOF
+	git tag -m nested nested annotated-v4.0 2>actual &&
+	test_i18ncmp expect actual
+'
+
 test_expect_success 'multiple --points-at are OR-ed together' '
 	cat >expect <<-\EOF &&
 	v2.0
