rebase-merges: try and use branch names as labels
When interactively rebasing merge commits, the commit message is parsed to extract a probably meaningful label name. For instance if the merge commit is “Merge branch 'feature0'”, then the rebase script will have thes lines: ``` label feature0 merge -C $sha feature0 # “Merge branch 'feature0' ``` This heuristic fails in the case of octopus merges or when the merge commit message is actually unrelated to the parent commits. An example that combines both is: ``` *---. 967bfa4 (HEAD -> integration) Integration |\ \ \ | | | * 2135be1 (feature2, feat2) Feature 2 | |_|/ |/| | | | * c88b01a Feature 1 | |/ |/| | * 75f3139 (feat0) Feature 0 |/ * 25c86d0 (main) Initial commit ``` yields the labels Integration, Integration-2 and Integration-3. Fix this by using a branch name for each merge commit's parent that is the tip of at least one branch, and falling back to a label derived from the merge commit message otherwise. In the example above, the labels become feat0, Integration and feature2. Signed-off-by: Nicolas Guichard <nicolas@guichard.eu> Acked-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Nicolas Guichard committed
Oct 9, 2024 at 07:58 UTC
436892123dd9d442fe4f534bba6f7ead635db06c
3 files changed
+25
-16
sequencer.c
+17
-8
@@ -5819,7 +5819,7 @@ static int make_script_with_merges(struct pretty_print_context *pp,
5819
int root_with_onto = flags & TODO_LIST_ROOT_WITH_ONTO;
5820
int skipped_commit = 0;
5821
struct strbuf buf = STRBUF_INIT, oneline = STRBUF_INIT;
5822
- struct strbuf label = STRBUF_INIT;
5822
+ struct strbuf label_from_message = STRBUF_INIT;
5823
struct commit_list *commits = NULL, **tail = &commits, *iter;
5824
struct commit_list *tips = NULL, **tips_tail = &tips;
5825
struct commit *commit;
@@ -5842,6 +5842,7 @@ static int make_script_with_merges(struct pretty_print_context *pp,
5842
oidmap_init(&state.commit2label, 0);
5843
hashmap_init(&state.labels, labels_cmp, NULL, 0);
5844
strbuf_init(&state.buf, 32);
5845
+ load_branch_decorations();
5846
5847
if (revs->cmdline.nr && (revs->cmdline.rev[0].flags & BOTTOM)) {
5848
struct labels_entry *onto_label_entry;
@@ -5902,18 +5903,18 @@ static int make_script_with_merges(struct pretty_print_context *pp,
5903
continue;
5904
}
5905
5905
- /* Create a label */
5906
- strbuf_reset(&label);
5906
+ /* Create a label from the commit message */
5907
+ strbuf_reset(&label_from_message);
5908
if (skip_prefix(oneline.buf, "Merge ", &p1) &&
5909
(p1 = strchr(p1, '\'')) &&
5910
(p2 = strchr(++p1, '\'')))
5910
- strbuf_add(&label, p1, p2 - p1);
5911
+ strbuf_add(&label_from_message, p1, p2 - p1);
5912
else if (skip_prefix(oneline.buf, "Merge pull request ",
5913
&p1) &&
5914
(p1 = strstr(p1, " from ")))
5914
- strbuf_addstr(&label, p1 + strlen(" from "));
5915
+ strbuf_addstr(&label_from_message, p1 + strlen(" from "));
5916
else
5916
- strbuf_addbuf(&label, &oneline);
5917
+ strbuf_addbuf(&label_from_message, &oneline);
5918
5919
strbuf_reset(&buf);
5920
strbuf_addf(&buf, "%s -C %s",
@@ -5921,6 +5922,14 @@ static int make_script_with_merges(struct pretty_print_context *pp,
5922
5923
/* label the tips of merged branches */
5924
for (; to_merge; to_merge = to_merge->next) {
5925
+ const char *label = label_from_message.buf;
5926
+ const struct name_decoration *decoration =
5927
+ get_name_decoration(&to_merge->item->object);
5928
+
5929
+ if (decoration)
5930
+ skip_prefix(decoration->name, "refs/heads/",
5931
+ &label);
5932
+
5933
oid = &to_merge->item->object.oid;
5934
strbuf_addch(&buf, ' ');
5935
@@ -5933,7 +5942,7 @@ static int make_script_with_merges(struct pretty_print_context *pp,
5942
tips_tail = &commit_list_insert(to_merge->item,
5943
tips_tail)->next;
5944
5936
- strbuf_addstr(&buf, label_oid(oid, label.buf, &state));
5945
+ strbuf_addstr(&buf, label_oid(oid, label, &state));
5946
}
5947
strbuf_addf(&buf, " # %s", oneline.buf);
5948
@@ -6041,7 +6050,7 @@ static int make_script_with_merges(struct pretty_print_context *pp,
6050
free_commit_list(commits);
6051
free_commit_list(tips);
6052
6044
- strbuf_release(&label);
6053
+ strbuf_release(&label_from_message);
6054
strbuf_release(&oneline);
6055
strbuf_release(&buf);
6056
t/t3404-rebase-interactive.sh
+2
-2
@@ -1870,7 +1870,7 @@ test_expect_success '--update-refs adds commands with --rebase-merges' '
1870
pick $(git log -1 --format=%h branch2~1) F
1871
pick $(git log -1 --format=%h branch2) I
1872
update-ref refs/heads/branch2
1873
- label merge
1873
+ label branch2
1874
reset onto
1875
pick $(git log -1 --format=%h refs/heads/second) J
1876
update-ref refs/heads/second
@@ -1881,7 +1881,7 @@ test_expect_success '--update-refs adds commands with --rebase-merges' '
1881
update-ref refs/heads/third
1882
pick $(git log -1 --format=%h HEAD~2) M
1883
update-ref refs/heads/no-conflict-branch
1884
- merge -C $(git log -1 --format=%h HEAD~1) merge # merge
1884
+ merge -C $(git log -1 --format=%h HEAD~1) branch2 # merge
1885
update-ref refs/heads/merge-branch
1886
EOF
1887
t/t3430-rebase-merges.sh
+6
-6
@@ -108,19 +108,19 @@ test_expect_success 'generate correct todo list' '
108
109
reset onto
110
pick $b B
111
- label E
111
+ label first
112
113
reset onto
114
pick $c C
115
label branch-point
116
pick $f F
117
pick $g G
118
- label H
118
+ label second
119
120
reset branch-point # C
121
pick $d D
122
- merge -C $e E # E
123
- merge -C $h H # H
122
+ merge -C $e first # E
123
+ merge -C $h second # H
124
125
EOF
126
@@ -462,11 +462,11 @@ test_expect_success 'A root commit can be a cousin, treat it that way' '
462
'
463
464
test_expect_success 'labels that are object IDs are rewritten' '
465
- git checkout -b third B &&
465
+ git checkout --detach B &&
466
test_commit I &&
467
third=$(git rev-parse HEAD) &&
468
git checkout -b labels main &&
469
- git merge --no-commit third &&
469
+ git merge --no-commit $third &&
470
test_tick &&
471
git commit -m "Merge commit '\''$third'\'' into labels" &&
472
echo noop >script-from-scratch &&