revision.c: implement --max-count-oldest
"--max-count" is a commit limiting option and sets a maximum amount
of commits to be shown. If a user wants to see only the first N
commits of the history (the oldest commits) they'd have to do
something like
git log $(git rev-list HEAD | tail -n N | head -n 1)
This is not very user-friendly.
Teach get_revision() the --max-count-oldest option.
Signed-off-by: Mirko Faina <mroik@delayed.space>
[jc: fixed up t4202 <xmqq7boy4o05.fsf@gitster.g>]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/rev-list-options.adoc b/Documentation/rev-list-options.adoc
index 2d195a1..e8c88d0 100644
--- a/Documentation/rev-list-options.adoc
+++ b/Documentation/rev-list-options.adoc
@@ -16,7 +16,10 @@
`-<number>`::
`-n <number>`::
`--max-count=<number>`::
- Limit the output to _<number>_ commits.
+ Limit the output to the first _<number>_ commits that would be shown.
+
+`--max-count-oldest=<number>`::
+ Limit the output to the last _<number>_ commits that would be shown.
`--skip=<number>`::
Skip _<number>_ commits before starting to show the commit output.
diff --git a/revision.c b/revision.c
index 599b3a6..5d53db3 100644
--- a/revision.c
+++ b/revision.c
@@ -2339,10 +2339,28 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
}
if ((argcount = parse_long_opt("max-count", argv, &optarg))) {
+ if (revs->max_count_type == 1)
+ die_for_incompatible_opt2(1, "--max-count", 1,
+ "--max-count-oldest");
revs->max_count = parse_count(optarg);
revs->no_walk = 0;
+ revs->max_count_type = 0;
return argcount;
+ } else if ((argcount = parse_long_opt("max-count-oldest", argv, &optarg))) {
+ if (revs->max_count_type == 0 && revs->max_count != -1)
+ die_for_incompatible_opt2(1, "--max-count", 1,
+ "--max-count-oldest");
+ if (revs->skip_count > 0)
+ die_for_incompatible_opt2(1, "--skip", 1,
+ "--max-count-oldest");
+ revs->max_count = parse_count(optarg);
+ revs->no_walk = 0;
+ revs->max_count_type = 1;
+ revs->max_count_stage = 0;
} else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
+ if (revs->max_count_type == 1)
+ die_for_incompatible_opt2(1, "--skip", 1,
+ "--max-count-oldest");
revs->skip_count = parse_count(optarg);
return argcount;
} else if ((*arg == '-') && isdigit(arg[1])) {
@@ -4521,15 +4539,91 @@ static struct commit *get_revision_internal(struct rev_info *revs)
return c;
}
+static void retrieve_oldest_commits(struct rev_info *revs,
+ struct commit_list **queue)
+{
+ struct commit *c;
+ int max_count = revs->max_count;
+ int queuei_count = 0;
+ int queueo_count = 0;
+ struct commit_list *queueo = NULL;
+ struct commit_list *queuei = NULL;
+ struct commit_list *reversed_queue = NULL;
+ struct commit_list *p;
+
+ revs->max_count = -1;
+ while ((c = get_revision_internal(revs))) {
+ /*
+ * We need to reset SHOWN status otherwise --graph breaks.
+ * It is fine to do, get_revision_internal() doesn't consider
+ * children commits as they have been already processed and the
+ * traversal happens only child to parent.
+ *
+ * We do this because the --graph machinery relies on the status
+ * of the parents to decide how the printing will happen.
+ *
+ * We can't simply replace this instruction with a
+ * graph_update() as it doesn't do the actualy printing, we'd
+ * have to remove any commit that goes over the
+ * --max-count-oldest limit from revs->graph.
+ */
+ c->object.flags &= ~(SHOWN | CHILD_SHOWN);
+ commit_list_insert(c, &queuei);
+ if (!(c->object.flags & BOUNDARY))
+ queuei_count++;
+ while (queuei_count + queueo_count > max_count) {
+ if (!queueo_count) {
+ while ((c = pop_commit(&queuei))) {
+ commit_list_insert(c, &queueo);
+ queueo_count++;
+ }
+ queuei_count = 0;
+ }
+ c = pop_commit(&queueo);
+ queueo_count--;
+ /* We need to do this otherwise we'll discard the
+ * commits that go over the --max-count-oldest limit but
+ * not their respective boundaries. This matters only if
+ * we're discarding the commit right before the boundary.
+ */
+ for (p = c->parents; p; p = p->next)
+ p->item->object.flags &= ~CHILD_SHOWN;
+ }
+ }
+
+ while ((c = pop_commit(&queueo)))
+ commit_list_insert(c, &reversed_queue);
+ while ((c = pop_commit(&queuei)))
+ commit_list_insert(c, &queueo);
+ while ((c = pop_commit(&queueo)))
+ commit_list_insert(c, &reversed_queue);
+
+ while ((c = pop_commit(&reversed_queue)))
+ commit_list_insert(c, queue);
+}
+
struct commit *get_revision(struct rev_info *revs)
{
struct commit *c;
struct commit_list *reversed;
+ struct commit_list *queue = NULL;
+ struct commit_list *p;
+
+ if (revs->max_count_type == 1 && !revs->max_count_stage) {
+ retrieve_oldest_commits(revs, &queue);
+ commit_list_free(revs->commits);
+ revs->commits = queue;
+ revs->max_count_stage = 1;
+ }
if (revs->reverse) {
reversed = NULL;
- while ((c = get_revision_internal(revs)))
- commit_list_insert(c, &reversed);
+ if (revs->max_count_type == 1)
+ while ((c = pop_commit(&revs->commits)))
+ commit_list_insert(c, &reversed);
+ else
+ while ((c = get_revision_internal(revs)))
+ commit_list_insert(c, &reversed);
commit_list_free(revs->commits);
revs->commits = reversed;
revs->reverse = 0;
@@ -4543,7 +4637,18 @@ struct commit *get_revision(struct rev_info *revs)
return c;
}
- c = get_revision_internal(revs);
+ if (revs->max_count_stage) {
+ c = pop_commit(&revs->commits);
+ if (c) {
+ c->object.flags |= SHOWN;
+ if (!(c->object.flags & BOUNDARY))
+ for (p = c->parents; p; p = p->next)
+ p->item->object.flags |= CHILD_SHOWN;
+ }
+ } else {
+ c = get_revision_internal(revs);
+ }
+
if (c && revs->graph)
graph_update(revs->graph, c);
if (!c) {
diff --git a/revision.h b/revision.h
index 584f133..e157463 100644
--- a/revision.h
+++ b/revision.h
@@ -309,6 +309,8 @@ struct rev_info {
/* special limits */
int skip_count;
int max_count;
+ unsigned int max_count_type:1;
+ unsigned int max_count_stage:1;
timestamp_t max_age;
timestamp_t max_age_as_filter;
timestamp_t min_age;
diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 05cee9e..75edb0e 100755
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -1882,6 +1882,46 @@
test_cmp_graph --name-status tangle..reach
'
+test_expect_success 'log --max-count-oldest=3 --oneline' '
+ test_when_finished rm expect &&
+ git log --oneline | tail -n3 >expect &&
+ git log --oneline --max-count-oldest=3 >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'log --max-count-oldest=3 --reverse --oneline' '
+ test_when_finished rm expect &&
+ git log --oneline --reverse | head -n3 >expect &&
+ git log --oneline --max-count-oldest=3 --reverse >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'log --max-count-oldest with --max-count' '
+ test_when_finished rm stderr &&
+ test_must_fail git log --max-count-oldest=3 --max-count=3 2>stderr &&
+ test_grep "cannot be used together" stderr
+'
+
+test_expect_success 'log --max-count-oldest with --skip' '
+ test_when_finished rm stderr &&
+ test_must_fail git log --max-count-oldest=3 --skip=1 2>stderr &&
+ test_grep "cannot be used together" stderr
+'
+
+test_expect_success 'log --max-count-oldest=1000 --graph --boundary' '
+ test_when_finished rm expect actual &&
+ git log --graph --boundary >expect &&
+ git log --max-count-oldest=1000 --graph --boundary >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'log --oneline --graph --boundary --max-count-oldest=1' '
+ test_when_finished rm -f actual &&
+ git log --oneline --graph --boundary --max-count-oldest=1 \
+ HEAD~1..HEAD >actual &&
+ test_line_count = 2 actual
+'
+
cat >expect <<-\EOF
* reach
|
