Commit `b6b09c54da`

b6b09c54da3f200e5a91d2be1c0e6902314ed098

parent: 85a32ad0bd

Verified · cmc

cmc <hello@cleberg.net> · 2026-08-24 03:14 UTC

mrs: preserve merged diffs

A fast-forward makes the live merge-base equal the MR head, so merged
MRs showed an empty diff. Record the target tip at merge time
(merged_base, migration 0006) and use it as the diff base for merged
MRs in mr diff and the web view; open MRs keep the live computation.

Layout: unified · split

e2e/mr_test.go +10

		@@ -248,6 +248,13 @@ func TestMergeRequests(t *testing.T) {
248	248	t.Fatalf("merge after fork deletion: %s", errOut)
249	249	}
250	250
	251	// Merged MRs keep their historical diff: after the fast-forward the
	252	// live merge-base equals the head, so the recorded base must be used.
	253	diffOut2, _, code := inst.ssh(t, aliceKey, "", "mr", "diff", "alice/lib", "1")
	254	if code != 0 \|\| !strings.Contains(diffOut2, "feature.txt") {
	255	t.Fatalf("post-merge diff empty: %d\n%s", code, diffOut2)
	256	}
	257
251	258	// Web read views.
252	259	status, body := inst.get(t, "/alice/lib/mrs?state=all")
253	260	if status != 200 \|\| !strings.Contains(body, "add feature") \|\| !strings.Contains(body, "second") {
		@@ -257,4 +264,7 @@ func TestMergeRequests(t *testing.T) {
257	264	if status != 200 \|\| !strings.Contains(body, "stale") \|\| !strings.Contains(body, "merged") {
258	265	t.Fatalf("mr detail: %d\n%s", status, body)
259	266	}
	267	if !strings.Contains(body, "feature.txt") {
	268	t.Fatalf("merged MR web diff empty:\n%s", body)
	269	}
260	270	}

internal/control/mr.go +10 −4

		@@ -352,9 +352,15 @@ func runMRDiff(c *Ctx, args []string) int {
352	352	}
353	353	dir := RepoDir(c.Cfg.Server.Root, repo.OwnerName, repo.Name)
354	354	head := mrHeadRef(mr.Number)
355		base, err := gitutil.MergeBase(dir, "refs/heads/"+mr.TargetRef, head)
356		if err != nil {
357		return c.fail(protocol.ExitFailure, "%v", err)
	355	// After a merge (especially fast-forward) the live merge-base equals
	356	// the head and the diff would vanish; use the recorded base instead.
	357	base := mr.MergedBase
	358	if base == "" {
	359	b, err := gitutil.MergeBase(dir, "refs/heads/"+mr.TargetRef, head)
	360	if err != nil {
	361	return c.fail(protocol.ExitFailure, "%v", err)
	362	}
	363	base = b
358	364	}
359	365	patch, err := gitutil.Diff(dir, base, head, 4<<20)
360	366	if err != nil {
		@@ -663,7 +669,7 @@ func runMRMerge(c *Ctx, args []string) int {
663	669	if err := gitutil.UpdateRefCAS(dir, targetRef, newSHA, targetSHA); err != nil {
664	670	return c.fail(protocol.ExitFailure, "target branch moved during merge; retry: %v", err)
665	671	}
666		if err := c.Store.SetMRState(mr.ID, "merged"); err != nil {
	672	if err := c.Store.MarkMerged(mr.ID, targetSHA); err != nil {
667	673	return c.fail(protocol.ExitFailure, "%v", err)
668	674	}
669	675	c.Store.RecordEvent(repo.ID, c.User.ID, "mr.merged", fmt.Sprintf(`{"number":%d,"sha":%q}`, mr.Number, newSHA))

internal/httpd/web.go +7 −1

		@@ -642,7 +642,13 @@ func (s Server) mr(w http.ResponseWriter, r http.Request) {
642	642
643	643	headRef := fmt.Sprintf("refs/merge-requests/%d/head", m.Number)
644	644	var lines []diffLine
645		if base, err := gitutil.MergeBase(p.Dir, "refs/heads/"+m.TargetRef, headRef); err == nil {
	645	base := m.MergedBase
	646	if base == "" {
	647	if b, err := gitutil.MergeBase(p.Dir, "refs/heads/"+m.TargetRef, headRef); err == nil {
	648	base = b
	649	}
	650	}
	651	if base != "" {
646	652	if patch, err := gitutil.Diff(p.Dir, base, headRef, 4<<20); err == nil {
647	653	lines = classifyDiff(patch)
648	654	}

internal/store/migrations/0006_merged_base.down.sql added +1

		@@ -0,0 +1 @@
	1	ALTER TABLE merge_requests DROP COLUMN merged_base;

internal/store/migrations/0006_merged_base.up.sql added +1

		@@ -0,0 +1 @@
	1	ALTER TABLE merge_requests ADD COLUMN merged_base TEXT NOT NULL DEFAULT '';

internal/store/mrs.go +12 −2

		@@ -18,6 +18,7 @@ type MR struct {
18	18	Body string
19	19	State string // open \| merged \| closed \| source_gone
20	20	HeadSHA string
	21	MergedBase string // target tip at merge time; base for historical diffs
21	22	CreatedAt string
22	23	UpdatedAt string
23	24	}
		@@ -57,7 +58,7 @@ const mrSelect = `
57	58	COALESCE(m.source_repo_id, 0),
58	59	COALESCE(COALESCE(su.username, so.name) \|\| '/' \|\| sr.name, ''),
59	60	m.source_ref, m.target_ref, m.title, m.body, m.state, m.head_sha,
60		m.created_at, m.updated_at
	61	m.merged_base, m.created_at, m.updated_at
61	62	FROM merge_requests m
62	63	JOIN users u ON u.id = m.author_id
63	64	LEFT JOIN repos sr ON sr.id = m.source_repo_id
		@@ -67,7 +68,7 @@ const mrSelect = `
67	68	func scanMR(row interface{ Scan(...any) error }) (MR, error) {
68	69	var m MR
69	70	err := row.Scan(&m.ID, &m.RepoID, &m.Number, &m.Author, &m.SourceRepoID, &m.SourcePath,
70		&m.SourceRef, &m.TargetRef, &m.Title, &m.Body, &m.State, &m.HeadSHA, &m.CreatedAt, &m.UpdatedAt)
	71	&m.SourceRef, &m.TargetRef, &m.Title, &m.Body, &m.State, &m.HeadSHA, &m.MergedBase, &m.CreatedAt, &m.UpdatedAt)
71	72	return m, err
72	73	}
73	74
		@@ -124,6 +125,15 @@ func (s *Store) OpenMRsBySource(sourceRepoID int64, sourceRef string) ([]MR, err
124	125	return out, rows.Err()
125	126	}
126	127
	128	// MarkMerged records the merge along with the target tip it landed on, so
	129	// the MR's diff stays reconstructable after fast-forwards.
	130	func (s *Store) MarkMerged(mrID int64, baseSHA string) error {
	131	_, err := s.DB.Exec(
	132	"UPDATE merge_requests SET state = 'merged', merged_base = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ','now') WHERE id = ?",
	133	baseSHA, mrID)
	134	return err
	135	}
	136
127	137	func (s *Store) SetMRState(mrID int64, state string) error {
128	138	res, err := s.DB.Exec(
129	139	"UPDATE merge_requests SET state = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ','now') WHERE id = ?",

Commit b6b09c54da

Commit `b6b09c54da`