Users who are accustomed to doing `git checkout <tag>` assume that
`git switch <tag>` will do the same thing. Inform them of the --detach
option so they aren't left wondering why `git switch` doesn't work but
`git checkout` does.
Signed-off-by: Alex Henrie <alexhenrie24@xxxxxxxxx>
---
v2:
- Rephrase advice
- Print advice after error message
- Create a new config variable to suppress the advice
- Add tests
---
Documentation/config/advice.txt | 3 +++
advice.c | 1 +
advice.h | 1 +
builtin/checkout.c | 30 +++++++++++++++++++-----------
t/t2060-switch.sh | 11 +++++++++++
5 files changed, 35 insertions(+), 11 deletions(-)
diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index adee26fbbb..c40eb09cb7 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -85,6 +85,9 @@ advice.*::
linkgit:git-switch[1] or linkgit:git-checkout[1]
to move to the detach HEAD state, to instruct how to
create a local branch after the fact.
+ suggestDetachingHead::
+ Advice shown when linkgit:git-switch[1] refuses to detach HEAD
+ without the explicit `--detach` option.
checkoutAmbiguousRemoteBranchName::
Advice shown when the argument to
linkgit:git-checkout[1] and linkgit:git-switch[1]
diff --git a/advice.c b/advice.c
index e00d30254c..2e1fd48304 100644
--- a/advice.c
+++ b/advice.c
@@ -42,6 +42,7 @@ static struct {
[ADVICE_CHECKOUT_AMBIGUOUS_REMOTE_BRANCH_NAME] = { "checkoutAmbiguousRemoteBranchName", 1 },
[ADVICE_COMMIT_BEFORE_MERGE] = { "commitBeforeMerge", 1 },
[ADVICE_DETACHED_HEAD] = { "detachedHead", 1 },
+ [ADVICE_SUGGEST_DETACHING_HEAD] = { "suggestDetachingHead", 1 },
[ADVICE_FETCH_SHOW_FORCED_UPDATES] = { "fetchShowForcedUpdates", 1 },
[ADVICE_GRAFT_FILE_DEPRECATED] = { "graftFileDeprecated", 1 },
[ADVICE_IGNORED_HOOK] = { "ignoredHook", 1 },
diff --git a/advice.h b/advice.h
index a7521d6087..a3957123a1 100644
--- a/advice.h
+++ b/advice.h
@@ -20,6 +20,7 @@ struct string_list;
ADVICE_CHECKOUT_AMBIGUOUS_REMOTE_BRANCH_NAME,
ADVICE_COMMIT_BEFORE_MERGE,
ADVICE_DETACHED_HEAD,
+ ADVICE_SUGGEST_DETACHING_HEAD,
ADVICE_FETCH_SHOW_FORCED_UPDATES,
ADVICE_GRAFT_FILE_DEPRECATED,
ADVICE_IGNORED_HOOK,
diff --git a/builtin/checkout.c b/builtin/checkout.c
index d9b31bbb6d..9244827ca0 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -1397,23 +1397,31 @@ static void die_expecting_a_branch(const struct branch_info *branch_info)
{
struct object_id oid;
char *to_free;
+ int code;
if (dwim_ref(branch_info->name, strlen(branch_info->name), &oid, &to_free, 0) == 1) {
const char *ref = to_free;
if (skip_prefix(ref, "refs/tags/", &ref))
- die(_("a branch is expected, got tag '%s'"), ref);
- if (skip_prefix(ref, "refs/remotes/", &ref))
- die(_("a branch is expected, got remote branch '%s'"), ref);
- die(_("a branch is expected, got '%s'"), ref);
+ code = die_message(_("a branch is expected, got tag '%s'"), ref);
+ else if (skip_prefix(ref, "refs/remotes/", &ref))
+ code = die_message(_("a branch is expected, got remote branch '%s'"), ref);
+ else
+ code = die_message(_("a branch is expected, got '%s'"), ref);
}
- if (branch_info->commit)
- die(_("a branch is expected, got commit '%s'"), branch_info->name);
- /*
- * This case should never happen because we already die() on
- * non-commit, but just in case.
- */
- die(_("a branch is expected, got '%s'"), branch_info->name);
+ else if (branch_info->commit)
+ code = die_message(_("a branch is expected, got commit '%s'"), branch_info->name);
+ else
+ /*
+ * This case should never happen because we already die() on
+ * non-commit, but just in case.
+ */
+ code = die_message(_("a branch is expected, got '%s'"), branch_info->name);
+
+ if (advice_enabled(ADVICE_SUGGEST_DETACHING_HEAD))
+ advise(_("If you want to detach HEAD at the commit, try again with the --detach option."));
+
+ exit(code);
}
static void die_if_some_operation_in_progress(void)
diff --git a/t/t2060-switch.sh b/t/t2060-switch.sh
index ebb961be29..f54691bac9 100755
--- a/t/t2060-switch.sh
+++ b/t/t2060-switch.sh
@@ -32,6 +32,17 @@ test_expect_success 'switch and detach' '
test_must_fail git symbolic-ref HEAD
'
+test_expect_success 'suggestion to detach' '
+ test_must_fail git switch main^{commit} 2>stderr &&
+ test_i18ngrep "try again with the --detach option" stderr
+'
+
+test_expect_success 'suggestion to detach is suppressed with advice.suggestDetachingHead=false' '
+ test_config advice.suggestDetachingHead false &&
+ test_must_fail git switch main^{commit} 2>stderr &&
+ test_i18ngrep ! "try again with the --detach option" stderr
+'
+
test_expect_success 'switch and detach current branch' '
test_when_finished git switch main &&
git switch main &&
--
2.35.1
