@matheusbsbs / matheus-bagliano / commits / 7740ac691d

rebase: dereference tags

A rebase started with 'git rebase <A> <B>' is conceptually to first checkout <B> and run 'git rebase <A>' starting from that state. 'git rebase --abort' in the middle of such a rebase should take us back to the state we checked out <B>. This used to work, even when <B> is a tag that points at a commit, until Git 2.20.0 when the command was reimplemented in C. The command now complains that the tag object itself cannot be checked out, which may be technically correct but is not what the user asked to do. Fix this old regression by using lookup_commit_reference_by_name() when parsing <B>. The scripted version did not need to peel the tag because the commands it passed the tag to (e.g 'git reset') peeled the tag themselves. Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Phillip Wood committed Sep 21, 2021 at 10:24 UTC 7740ac691d8e7f1bed67bcbdb1ee5c5c618f7373
2 files changed +22 -10
builtin/rebase.c
+8 -6
@@ -1905,13 +1905,15 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
1905 die_if_checked_out(buf.buf, 1);
1906 options.head_name = xstrdup(buf.buf);
1907 /* If not is it a valid ref (branch or commit)? */
1908 - } else if (!get_oid(branch_name, &options.orig_head) &&
1909 - lookup_commit_reference(the_repository,
1910 - &options.orig_head))
1908 + } else {
1909 + struct commit *commit =
1910 + lookup_commit_reference_by_name(branch_name);
1911 + if (!commit)
1912 + die(_("no such branch/commit '%s'"),
1913 + branch_name);
1914 + oidcpy(&options.orig_head, &commit->object.oid);
1915 options.head_name = NULL;
1912 - else
1913 - die(_("no such branch/commit '%s'"),
1914 - branch_name);
1916 + }
1917 } else if (argc == 0) {
1918 /* Do not need to switch branches, we are already on it. */
1919 options.head_name =
t/t3407-rebase-abort.sh
+14 -4
@@ -11,18 +11,18 @@ test_expect_success setup '
11 test_commit a a a &&
12 git branch to-rebase &&
13
14 - test_commit b a b &&
15 - test_commit c a c &&
14 + test_commit --annotate b a b &&
15 + test_commit --annotate c a c &&
16
17 git checkout to-rebase &&
18 test_commit "merge should fail on this" a d d &&
19 - test_commit "merge should fail on this, too" a e pre-rebase
19 + test_commit --annotate "merge should fail on this, too" a e pre-rebase
20 '
21
22 # Check that HEAD is equal to "pre-rebase" and the current branch is
23 # "to-rebase"
24 check_head() {
25 - test_cmp_rev HEAD pre-rebase &&
25 + test_cmp_rev HEAD pre-rebase^{commit} &&
26 test "$(git symbolic-ref HEAD)" = refs/heads/to-rebase
27 }
28
@@ -67,6 +67,16 @@ testrebase() {
67 test_path_is_missing "$state_dir"
68 '
69
70 + test_expect_success "rebase$type --abort when checking out a tag" '
71 + test_when_finished "git symbolic-ref HEAD refs/heads/to-rebase" &&
72 + git reset --hard a -- &&
73 + test_must_fail git rebase$type --onto b c pre-rebase &&
74 + test_cmp_rev HEAD b^{commit} &&
75 + git rebase --abort &&
76 + test_cmp_rev HEAD pre-rebase^{commit} &&
77 + ! git symbolic-ref HEAD
78 + '
79 +
80 test_expect_success "rebase$type --abort does not update reflog" '
81 # Clean up the state from the previous one
82 git reset --hard pre-rebase &&