Say the verdict in a line of at most 140 characters and owe the status mesh/check in the checker's bucket, which the forge bridge performs once per revision; the checker's stream checks wakes the readers of its buckets (issues 1682, 1683)

2026-10-21 21:20:42 +02:00
parent 4242fb5b0b
commit 96ba6bd3dc
19 changed files with 646 additions and 43 deletions
@@ -23,7 +23,7 @@ type judgeDeps struct {
 	kept     check.KV
 	previews check.KV
 	repos    *repoModules
-	announce func(ctx context.Context, key string)
+	announce check.Announcer
 	logf     func(format string, args ...any)
 }

@@ -32,9 +32,11 @@ import (
 	"mesh-delivery-checker/internal/check"
 )

-// previewWrittenSubject is the subject of the checker's preview.written event, on its stream previews (the bus names the
-// stream PREVIEWS); the indexer's watch of the previews bucket is woken by it.
-const previewWrittenSubject = "mesh.stream." + delivery.CheckerModule + ".event.preview.written"
+// eventSubject is the subject of an event of the checker's stream checks (the bus names the stream CHECKS): the indexer's
+// watch of the previews bucket and the forge bridge's watch of the owed bucket are woken by them.
+func eventSubject(event string) string {
+	return "mesh.stream." + delivery.CheckerModule + ".event." + event
+}

 const (
 	// defaultStepBound is how long the checker waits for one step of a build module (a fetch downloads the Go modules, a
@@ -196,18 +198,20 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		Link:     link,
 		Logf:     logger.Printf,
 	}
+	announce := func(ctx context.Context, event, key string) {
+		body, _ := json.Marshal(map[string]string{"key": key})
+		if _, err := js.Publish(ctx, eventSubject(event), body); err != nil {
+			logger.Printf("%s of %s was written and the part that reads it could not be told: %v", event, key, err)
+		}
+	}
 	repos := &repoModules{manifests: kvStore{buckets[delivery.ManifestsBucket]}, logf: logger.Printf}
 	ch.Judge = newJudge(judgeDeps{
 		runner: runner, tools: tools, presence: presence, have: have, places: places, trunks: trunks,
 		kept: kvStore{buckets[delivery.CheckerKeptBucket]}, previews: kvStore{buckets[delivery.PreviewsBucket]},
 		repos: repos, logf: logger.Printf,
-		announce: func(ctx context.Context, key string) {
-			body, _ := json.Marshal(map[string]string{"key": key})
-			if _, err := js.Publish(ctx, previewWrittenSubject, body); err != nil {
-				logger.Printf("previews.%s was written and the indexer could not be told: %v", key, err)
-			}
-		},
+		announce: announce,
 	})
+	ch.Announce = announce

 	// The toolchains first, so a check that starts from the first candidate finds the nodes.
 	watch := newToolchainWatch(ctx, js, tools, ch.NodesChanged, logger)
@@ -18,6 +18,17 @@ const DefaultBound = 30 * time.Minute
 // is judged again when the nodes change, by a watch and never a timer (ADR 0437 §8).
 const NodesWords = "build node qualifies"

+// The events the checker says on its stream checks (module.json): a preview or a status was written, so a part that reads
+// the bucket, which is made when the checker is assigned and may not exist when that part starts, finds it (ADR 0437 §8: no
+// timer). The body is {"key": ...}.
+const (
+	EventPreviewWritten = "preview.written"
+	EventOwedWritten    = "owed.written"
+)
+
+// Announcer says an event of the checker's stream, with the key written.
+type Announcer func(ctx context.Context, event, key string)
+
 // Outcome is what judging a case gives: the verdict (state, failure, levels, times, composition; the checker adds the
 // group, the heads and the trunk) and, for the line, what the check knows of the builds of the modules it touches.
 type Outcome struct {
@@ -56,8 +67,10 @@ type Checker struct {
 	Hold func() bool
 	// Link is the base of the address a status points at; the verdict key follows.
 	Link string
-	Now  func() time.Time
-	Logf func(format string, args ...any)
+	// Announce says a status was written (EventOwedWritten); nil says nothing.
+	Announce Announcer
+	Now      func() time.Time
+	Logf     func(format string, args ...any)

 	once      sync.Once
 	sem       chan struct{}
@@ -294,7 +307,7 @@ func (ch *Checker) try(ctx context.Context, key string, cs *Case) {
 		return
 	}
 	began := ch.now()
-	ch.writeOwed(ctx, cs, delivery.Verdict{State: delivery.VerdictRunning}, nil)
+	ch.writeOwed(ctx, cs, delivery.Verdict{State: delivery.VerdictRunning}, nil, nil)
 	out := ch.judge(ctx, cs)
 	if ctx.Err() != nil {
 		return
@@ -322,7 +335,7 @@ func (ch *Checker) try(ctx context.Context, key string, cs *Case) {
 		ch.nodesFail[cs.Key] = epoch
 		ch.mu.Unlock()
 	}
-	ch.writeOwed(ctx, cs, v, out.Builds)
+	ch.writeOwed(ctx, cs, v, out.Builds, out.Slowest)
 	ch.logf("%s: %s", cs.Key, v.State)
 }

@@ -360,7 +373,7 @@ func failure(machine, words string) delivery.Verdict {
 // writeOwed writes, for each pull request judged, the status the forge bridge performs: pending while the check runs, success
 // or failure at its end (ADR 0484 clause 2). A key already holding the same value is not written again, so the bridge
 // performs one act for each change; an older head's key is never touched.
-func (ch *Checker) writeOwed(ctx context.Context, cs *Case, v delivery.Verdict, builds []BuildNote) {
+func (ch *Checker) writeOwed(ctx context.Context, cs *Case, v delivery.Verdict, builds []BuildNote, slowest []string) {
 	for _, p := range cs.Pulls {
 		key, err := delivery.CheckerOwedKey(p.Repository, p.Number, p.Head)
 		if err != nil {
@@ -369,32 +382,35 @@ func (ch *Checker) writeOwed(ctx context.Context, cs *Case, v delivery.Verdict,
 		}
 		state := map[string]string{delivery.VerdictRunning: "pending", delivery.VerdictPass: "success", delivery.VerdictFail: "failure"}[v.State]
 		o := delivery.Owed{Act: delivery.OwedStatus, Context: delivery.StatusContextCheck, State: state,
-			Target: strings.TrimSuffix(ch.Link, "/") + "/" + cs.Key, Text: Line(v, cs, p, builds)}
+			Target: strings.TrimSuffix(ch.Link, "/") + "/" + cs.Key, Text: Line(v, cs, p, builds, slowest)}
 		data, err := delivery.EncodeCheckerOwed(o)
 		if err != nil {
 			ch.logf("%s: the status of %s cannot be written: %v", cs.Key, key, err)
 			continue
 		}
-		if err := putOnce(ctx, ch.Owed, key, data, func(cur []byte) bool {
+		wrote, err := putOnce(ctx, ch.Owed, key, data, func(cur []byte) bool {
 			held, err := delivery.DecodeCheckerOwed(cur)
 			o.V = delivery.Version
 			return err == nil && delivery.SameOwed(held, o)
-		}); err != nil {
+		})
+		if err != nil {
 			ch.logf("%s: the status of %s cannot be written: %v", cs.Key, key, err)
+		} else if wrote && ch.Announce != nil {
+			ch.Announce(ctx, EventOwedWritten, key)
 		}
 	}
 }

 // putOnce writes data under key by create, or by compare-and-set when the key exists, and writes nothing when same says the
 // key holds the value already.
-func putOnce(ctx context.Context, kv KV, key string, data []byte, same func(cur []byte) bool) error {
+func putOnce(ctx context.Context, kv KV, key string, data []byte, same func(cur []byte) bool) (bool, error) {
 	for try := 0; try < 4; try++ {
 		cur, rev, found, err := kv.Get(ctx, key)
 		if err != nil {
-			return err
+			return false, err
 		}
 		if found && same(cur) {
-			return nil
+			return false, nil
 		}
 		if !found {
 			_, err = kv.Create(ctx, key, data)
@@ -404,9 +420,9 @@ func putOnce(ctx context.Context, kv KV, key string, data []byte, same func(cur
 		if errors.Is(err, ErrConflict) {
 			continue
 		}
-		return err
+		return err == nil, err
 	}
-	return fmt.Errorf("%s changed under every one of 4 tries", key)
+	return false, fmt.Errorf("%s changed under every one of 4 tries", key)
 }

 // Sweep closes, at start, every verdict left running for a candidate that no longer holds those heads: nothing will check
@@ -365,3 +365,23 @@ func TestSweepClosesARunningKeyNoCandidateHoldsAndLeavesOneItDoes(t *testing.T)
 		t.Errorf("the live key = %+v, want it left for the check to take over", v)
 	}
 }
+
+func TestTheForgeBridgeIsToldOnceForEachChangeOfAStatus(t *testing.T) { // 1683 (the checker's half of AC5)
+	ctx, j := context.Background(), passJudge()
+	r := newRig(t, j)
+	var told []string
+	r.ch.Announce = func(_ context.Context, event, key string) { told = append(told, event+" "+key) }
+	cand := candidateOf(t, "feat/x", pullOf(repoA, 7, head1))
+	r.ch.Candidate(ctx, "feat%2Fx", cand)
+	r.ch.Wait()
+	key, _ := delivery.CheckerOwedKey(repoA, 7, head1)
+	want := []string{EventOwedWritten + " " + key, EventOwedWritten + " " + key} // pending, then success
+	if len(told) != 2 || told[0] != want[0] || told[1] != want[1] {
+		t.Fatalf("told %v, want the status said when pending and when success", told)
+	}
+	r.ch.Candidate(ctx, "feat%2Fx", cand) // nothing changed: nothing written, nothing said
+	r.ch.Wait()
+	if len(told) != 2 {
+		t.Errorf("told %v after a check that changed nothing", told)
+	}
+}
@@ -508,11 +508,11 @@ func TestAPreviewIsWrittenOnceAndAnExistingKeyStands(t *testing.T) {
 func TestTheIndexerIsToldOfAPreviewOnceWhenItIsCreated(t *testing.T) { // 1445/AC4 (the checker's half)
 	b := newBench(t)
 	var told []string
-	b.ex.Announce = func(_ context.Context, key string) { told = append(told, key) }
+	b.ex.Announce = func(_ context.Context, event, key string) { told = append(told, event+" "+key) }
 	b.judge(t, caseOf(t, pullOf(repoA, 7, head1)))
 	b.judge(t, caseOf(t, pullOf(repoA, 7, head1)))
 	key, _ := delivery.PreviewKey(repoA, head1, trunkA)
-	if len(told) != 1 || told[0] != key {
+	if len(told) != 1 || told[0] != EventPreviewWritten+" "+key {
 		t.Errorf("told %v, want once of %s", told, key)
 	}
 }
@@ -50,8 +50,8 @@ type Examiner struct {
 	// Previews is the previews bucket; nil writes none.
 	Previews KV
 	Modules  BuildModules
-	// Announce says a preview was written under the key (the checker's preview.written event); nil says nothing.
-	Announce func(ctx context.Context, key string)
+	// Announce says a preview was written under the key (EventPreviewWritten); nil says nothing.
+	Announce Announcer
 	// Trunks are the trunk heads of every repository, for the siblings a repository's tests read.
 	Trunks interface{ Heads() map[string]string }
 	Now    func() time.Time
@@ -2,13 +2,26 @@ package check

 import (
 	"fmt"
+	"strings"
+	"unicode/utf8"

 	"git.novox.be/novox/mesh-sdk/go/delivery"
 )

-// Line is the words of a status for one pull request of a case (ADR 0447 clause 3, ADR 0484 clause 7).
-func Line(v delivery.Verdict, cs *Case, p Pull, builds []BuildNote) string {
-	return fmt.Sprintf("%s: %s", v.State, short12(p.Head))
+// MaxLine is the most characters a status's line has: the forge shows a status's description in a short space, and the full
+// report is linked (ADR 0447 clause 3, ADR 0484 clause 7). A line that would be longer drops its lesser parts in a fixed
+// order, and is cut last.
+const MaxLine = 140
+
+// seconds is a time in milliseconds in the unit a person reads: 350ms, 4.1s, 72s.
+func seconds(ms int64) string {
+	switch {
+	case ms < 1000:
+		return fmt.Sprintf("%dms", ms)
+	case ms < 10000:
+		return fmt.Sprintf("%.1fs", float64(ms)/1000)
+	}
+	return fmt.Sprintf("%ds", (ms+500)/1000)
 }

 func short12(s string) string {
@@ -17,3 +30,155 @@ func short12(s string) string {
 	}
 	return s
 }
+
+// firstFailed is what failed first, in words: a conflict, a refused step or a test, named before anything else.
+func firstFailed(v delivery.Verdict) string {
+	f := v.Failed
+	switch {
+	case f.Test != "":
+		if f.Words != "" {
+			return f.Test + ": " + f.Words
+		}
+		return f.Test
+	case f.Machine != "" && f.Words != "":
+		return f.Machine + ": " + f.Words
+	case f.Machine != "":
+		return f.Machine
+	}
+	return f.Words
+}
+
+// pieces are the parts of a line, from the most to the least needed.
+type pieces struct {
+	head, commits, counts, times, over, builds, composition, group string
+}
+
+func (p pieces) join(drop int) string {
+	parts := []string{p.head, p.commits, p.counts}
+	if drop < 3 && p.times != "" {
+		parts = append(parts, p.times)
+	}
+	if p.over != "" {
+		parts = append(parts, p.over)
+	}
+	if drop < 1 && p.builds != "" {
+		parts = append(parts, p.builds)
+	}
+	if drop < 2 && p.group != "" {
+		parts = append(parts, p.group)
+	}
+	if p.composition != "" {
+		parts = append(parts, p.composition)
+	}
+	out := make([]string, 0, len(parts))
+	for _, s := range parts {
+		if s != "" {
+			out = append(out, s)
+		}
+	}
+	return strings.Join(out, " | ")
+}
+
+func levelWords(name string, r delivery.LevelResult) string {
+	s := fmt.Sprintf("%s %d run, %d kept", name, r.Run, r.Kept)
+	if r.Skipped > 0 {
+		s += fmt.Sprintf(", %d skipped", r.Skipped)
+	}
+	return s
+}
+
+func compositionWords(c *delivery.Composition) string {
+	switch {
+	case c == nil, c.State == delivery.CompositionNotRun:
+		return "composition not yet run"
+	case c.State == delivery.CompositionPass:
+		return "composition passed with " + short12(c.SDK)
+	}
+	return "composition failed: " + c.Words
+}
+
+func buildWords(builds []BuildNote) string {
+	if len(builds) == 0 {
+		return ""
+	}
+	parts := make([]string, len(builds))
+	for i, b := range builds {
+		parts[i] = b.Module + " " + b.State
+	}
+	return "builds: " + strings.Join(parts, ", ")
+}
+
+// parts makes the pieces of the line of a pull request of a case.
+func parts(v delivery.Verdict, cs *Case, p Pull, builds []BuildNote, slowest []string) pieces {
+	var pc pieces
+	commits := short12(p.Head) + " on " + short12(p.Trunk)
+	switch v.State {
+	case delivery.VerdictRunning:
+		pc.head = "checking " + commits
+	case delivery.VerdictPass:
+		pc.head = "pass " + commits
+	default:
+		pc.head = "failed: " + firstFailed(v)
+		pc.commits = commits
+	}
+	var counts []string
+	for _, level := range []string{delivery.LevelUnit, delivery.LevelIntegration} {
+		if r, ok := v.Levels[level]; ok {
+			counts = append(counts, levelWords(level, r))
+		}
+	}
+	pc.counts = strings.Join(counts, " | ")
+	if v.State != delivery.VerdictRunning {
+		t := v.Took
+		var times []string
+		for _, x := range []struct {
+			name string
+			ms   int64
+		}{{"queue", t.Queue}, {"clone", t.Clone}, {"unit", t.Unit}, {"int setup", t.IntegrationSetup}, {"int run", t.IntegrationRun}, {"composition", t.Composition}} {
+			if x.ms > 0 {
+				times = append(times, x.name+" "+seconds(x.ms))
+			}
+		}
+		if len(times) > 0 {
+			pc.times = strings.Join(times, ", ")
+		}
+	}
+	if len(v.OverBound) > 0 {
+		pc.over = "over bound: " + strings.Join(v.OverBound, ", ")
+		if len(slowest) > 0 {
+			pc.over += " (slowest " + strings.Join(slowest, ", ") + ")"
+		}
+	}
+	pc.builds = buildWords(builds)
+	if v.State != delivery.VerdictRunning {
+		pc.composition = compositionWords(v.Composition)
+	}
+	if cs != nil && len(cs.Pulls) > 1 {
+		pc.group = fmt.Sprintf("group %s of %d pull requests", cs.Group, len(cs.Pulls))
+		if v.State != delivery.VerdictPass {
+			pc.group = fmt.Sprintf("%s#%d in group %s", p.Repository, p.Number, cs.Group)
+		}
+	}
+	return pc
+}
+
+// Report is the full line of a pull request's status, with no limit: what the read tools and the full report say.
+func Report(v delivery.Verdict, cs *Case, p Pull, builds []BuildNote, slowest []string) string {
+	return parts(v, cs, p, builds, slowest).join(0)
+}
+
+// Line is the words of a status for one pull request of a case (ADR 0447 clause 3, ADR 0484 clause 7): the verdict first (a
+// failure names the conflict, the refused step or the test before anything), the head and the trunk commit as twelve
+// characters each, the tests run, kept and skipped per level, the time of each part, a level over its bound with its slowest
+// tests, the builds of the touched modules, and that the composition was not yet run. It is at most MaxLine characters: the
+// builds, then the group, then the times drop in that order, and the line is cut at last.
+func Line(v delivery.Verdict, cs *Case, p Pull, builds []BuildNote, slowest []string) string {
+	pc := parts(v, cs, p, builds, slowest)
+	for drop := 0; drop <= 3; drop++ {
+		if s := pc.join(drop); utf8.RuneCountInString(s) <= MaxLine {
+			return s
+		}
+	}
+	runes := []rune(pc.join(3))
+	return string(runes[:MaxLine-1]) + "…"
+}
@@ -0,0 +1,134 @@
+package check
+
+import (
+	"strings"
+	"testing"
+	"unicode/utf8"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func lineCase(t testing.TB, pulls ...delivery.CandidatePull) (*Case, Pull) {
+	cs := caseOf(t, pulls...)
+	return cs, cs.Pulls[0]
+}
+
+func passVerdict() delivery.Verdict {
+	return delivery.Verdict{State: delivery.VerdictPass,
+		Levels:      map[string]delivery.LevelResult{delivery.LevelUnit: {Run: 12, Kept: 301}, delivery.LevelIntegration: {Run: 3, Kept: 40}},
+		Took:        delivery.Took{Queue: 800, Clone: 4100, Unit: 400, IntegrationSetup: 3200, IntegrationRun: 12000},
+		Composition: &delivery.Composition{State: delivery.CompositionNotRun}}
+}
+
+func TestAPassOpensWithTheVerdictAndSaysTheCommitsTheCountsTheTimesAndThatTheCompositionWasNotRun(t *testing.T) { // 1300/AC1
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	full := Report(passVerdict(), cs, p, nil, nil)
+	for _, want := range []string{"pass 111111111111 on aaaaaaaaaaaa", "unit 12 run, 301 kept", "integration 3 run, 40 kept", "queue 800ms", "clone 4.1s", "unit 400ms", "int setup 3.2s", "int run 12s", "composition not yet run"} {
+		if !strings.Contains(full, want) {
+			t.Errorf("the report %q lacks %q", full, want)
+		}
+	}
+	if !strings.HasPrefix(full, "pass ") || strings.Contains(full, "composition passed") {
+		t.Errorf("report = %q", full)
+	}
+	line := Line(passVerdict(), cs, p, nil, nil)
+	if n := utf8.RuneCountInString(line); n > MaxLine {
+		t.Errorf("the line is %d characters, want at most %d: %q", n, MaxLine, line)
+	}
+	if !strings.HasPrefix(line, "pass 111111111111 on aaaaaaaaaaaa") || !strings.Contains(line, "composition not yet run") || !strings.Contains(line, "unit 12 run, 301 kept") {
+		t.Errorf("line = %q", line)
+	}
+}
+
+func TestAFailureNamesTheTestTheConflictOrTheRefusedStepFirst(t *testing.T) { // 1300/AC2
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	for name, c := range map[string]struct {
+		v    delivery.Verdict
+		want string
+	}{
+		"test":     {delivery.Verdict{State: delivery.VerdictFail, Failed: delivery.FailedFirst{Test: "unit: m/a.TestX", Words: "want 4"}}, "failed: unit: m/a.TestX: want 4"},
+		"conflict": {delivery.Verdict{State: delivery.VerdictFail, Failed: delivery.FailedFirst{Machine: "shanks", Words: "novox/mesh-delivery#7 does not merge into the trunk: files in conflict: go.mod"}}, "failed: shanks: novox/mesh-delivery#7 does not merge into the trunk: files in conflict: go.mod"},
+		"refused":  {delivery.Verdict{State: delivery.VerdictFail, Failed: delivery.FailedFirst{Machine: "mesh-build-go", Words: "no go build node qualifies: builders disagree"}}, "failed: mesh-build-go: no go build node qualifies"},
+	} {
+		line := Line(c.v, cs, p, nil, nil)
+		if !strings.HasPrefix(line, c.want) || !strings.Contains(line, "111111111111 on aaaaaaaaaaaa") {
+			t.Errorf("%s: line = %q, want it to open with %q and name the commits", name, line, c.want)
+		}
+	}
+}
+
+func TestALevelOverItsBoundIsNamedWithItsSlowestTestsAndTheVerdictIsNotChanged(t *testing.T) { // 1300/AC3
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	v := passVerdict()
+	v.OverBound = []string{"unit"}
+	line := Line(v, cs, p, nil, []string{"unit pkg.TestSlow 7.0s"})
+	if !strings.HasPrefix(line, "pass ") || !strings.Contains(Report(v, cs, p, nil, []string{"unit pkg.TestSlow 7.0s"}), "over bound: unit (slowest unit pkg.TestSlow 7.0s)") {
+		t.Errorf("line = %q", line)
+	}
+}
+
+func TestSkippedTestsAreSaidAndNeverAFlatPass(t *testing.T) { // 1300/AC6
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	v := passVerdict()
+	v.Levels[delivery.LevelUnit] = delivery.LevelResult{Run: 12, Kept: 301, Skipped: 2}
+	if line := Line(v, cs, p, nil, nil); !strings.Contains(line, "unit 12 run, 301 kept, 2 skipped") {
+		t.Errorf("line = %q", line)
+	}
+}
+
+func TestAGroupsMembersEachCarryTheSameVerdict(t *testing.T) { // 1300/AC4
+	cs := caseOf(t, pullOf(repoA, 7, head1), pullOf(repoSDK, 12, head2))
+	a := Line(passVerdict(), cs, cs.Pulls[0], nil, nil)
+	b := Line(passVerdict(), cs, cs.Pulls[1], nil, nil)
+	if !strings.HasPrefix(a, "pass ") || !strings.HasPrefix(b, "pass ") || !strings.Contains(Report(passVerdict(), cs, cs.Pulls[0], nil, nil), "group feat/x of 2 pull requests") {
+		t.Errorf("lines %q and %q", a, b)
+	}
+	if !strings.Contains(a, "111111111111") || !strings.Contains(b, "222222222222") {
+		t.Errorf("each member's line names its own head: %q and %q", a, b)
+	}
+}
+
+func TestTheBuildsOfTheTouchedModulesAreSaidAndDroppedFirstWhenTheLineIsTooLong(t *testing.T) { // ADR 0484 clause 7
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	builds := []BuildNote{{"avahi", "built"}, {"mesh-tools", "waiting"}}
+	if r := Report(passVerdict(), cs, p, builds, nil); !strings.Contains(r, "builds: avahi built, mesh-tools waiting") {
+		t.Errorf("report = %q", r)
+	}
+	line := Line(passVerdict(), cs, p, builds, nil)
+	if utf8.RuneCountInString(line) > MaxLine {
+		t.Errorf("line %q is too long", line)
+	}
+	short := passVerdict()
+	short.Took = delivery.Took{}
+	if l := Line(short, cs, p, builds[:1], nil); !strings.Contains(l, "builds: avahi built") {
+		t.Errorf("a short line keeps its builds: %q", l)
+	}
+}
+
+func TestALineIsNeverLongerThanTheLimit(t *testing.T) { // 1300/AC1
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	v := delivery.Verdict{State: delivery.VerdictFail, Failed: delivery.FailedFirst{Test: "integration: " + strings.Repeat("pkg/", 50) + ".TestSomething", Words: strings.Repeat("because ", 40)}}
+	if line := Line(v, cs, p, nil, nil); utf8.RuneCountInString(line) > MaxLine || !strings.HasPrefix(line, "failed: integration: ") {
+		t.Errorf("line = %q (%d)", line, utf8.RuneCountInString(line))
+	}
+}
+
+func TestARunningCheckIsPending(t *testing.T) {
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	if line := Line(delivery.Verdict{State: delivery.VerdictRunning}, cs, p, nil, nil); line != "checking 111111111111 on aaaaaaaaaaaa" {
+		t.Errorf("line = %q", line)
+	}
+}
+
+func TestThePassedCompositionIsSaidOnlyWhenItWasRun(t *testing.T) { // ADR 0484 clause 6
+	cs, p := lineCase(t, pullOf(repoA, 7, head1))
+	v := passVerdict()
+	v.Composition = &delivery.Composition{State: delivery.CompositionPass, SDK: "afbe371003a570f088be4a394d83aa7a9458f7ab"}
+	if r := Report(v, cs, p, nil, nil); !strings.Contains(r, "composition passed with afbe371003a5") {
+		t.Errorf("report = %q", r)
+	}
+	v.Composition = nil
+	if r := Report(v, cs, p, nil, nil); !strings.Contains(r, "composition not yet run") || strings.Contains(r, "composition passed") {
+		t.Errorf("a verdict with no composition: %q", r)
+	}
+}
@@ -63,7 +63,7 @@ func (j *Examiner) writePreview(ctx context.Context, p Pull, fetched []Fetched)
 				return
 			}
 			if err == nil && j.Announce != nil {
-				j.Announce(ctx, key)
+				j.Announce(ctx, EventPreviewWritten, key)
 			}
 		}
 	}
@@ -111,8 +111,8 @@ func TestManifestDeclarations(t *testing.T) { // 1678/AC1
 	if m.SecretsOwner != "mesh-delivery-checker" {
 		t.Errorf("secrets-owner = %q", m.SecretsOwner)
 	}
-	// The checker says each time it wrote a preview, so the indexer's watch finds the bucket (ADR 0484 clause 3).
-	if want := []stream{{Name: "previews", Events: []string{"preview.**"}}}; !reflect.DeepEqual(m.Streams, want) {
+	// The checker says each time it wrote a preview or a status, so the indexer's and the forge bridge's watches find the buckets (ADR 0484 clauses 2 and 3).
+	if want := []stream{{Name: "checks", Events: []string{"preview.**", "owed.**"}}}; !reflect.DeepEqual(m.Streams, want) {
 		t.Errorf("streams = %+v, want %+v", m.Streams, want)
 	}
 	for _, k := range []string{"logs", "emits", "claims", "provides", "requires", "uses", "defines-seats", "tools", "seat", "seats", "bus"} {
@@ -7,7 +7,7 @@
    "mesh-build-node.toolchain.reported"
  ],
  "streams": [
-    { "name": "previews", "events": ["preview.**"] }
+    { "name": "checks", "events": ["preview.**", "owed.**"] }
  ],
  "state": [
    { "name": "kept", "history": 1 },
@@ -91,9 +91,34 @@ func (p *performer) refuse(ctx context.Context, doneKey string, rev uint64, a br
 	return true
 }

-// owed performs the act an owed key asks at revision rev, once.
+// owed performs the act an owed key of the gate asks at revision rev, once.
 func (p *performer) owed(ctx context.Context, key string, rev uint64, value []byte) {
-	doneKey := "owed." + key
+	p.perform(ctx, "owed."+key, key, rev, value)
+}
+
+// checkOwed performs the status the checker owes on a head (mesh-delivery-checker_owed; novox/hq ADR 0484 clause 2) at
+// revision rev, once. Its keys are kept apart from the gate's, and a key that is not the checker's one act, the status
+// mesh/check, is left.
+func (p *performer) checkOwed(ctx context.Context, key string, rev uint64, value []byte) {
+	doneKey := "check." + key
+	if p.seen(ctx, doneKey, rev) {
+		return
+	}
+	if _, _, _, err := delivery.ParseCheckerOwedKey(key); err != nil {
+		p.logger.Printf("%s at revision %d is not a status of the checker, and is left: %v", key, rev, err)
+		p.keep(ctx, doneKey, rev)
+		return
+	}
+	if _, err := delivery.DecodeCheckerOwed(value); err != nil {
+		p.logger.Printf("%s at revision %d is not a status of the checker, and is left: %v", key, rev, err)
+		p.keep(ctx, doneKey, rev)
+		return
+	}
+	p.perform(ctx, doneKey, key, rev, value)
+}
+
+// perform does the act of an owed key once for the revision, under the bookkeeping key doneKey.
+func (p *performer) perform(ctx context.Context, doneKey, key string, rev uint64, value []byte) {
 	if p.seen(ctx, doneKey, rev) {
 		return
 	}
@@ -208,3 +208,57 @@ func TestAMergeWithTwoHandedStopsAtTheFirstRefusal(t *testing.T) { // ADR 0441
 		t.Errorf("calls %d messages %d, want the first refusal to stop the pass", len(f.calls), len(pub.data))
 	}
 }
+
+// checkerOwed is the status the checker owes, as it writes it (mesh-sdk go/delivery CheckerOwedKey, EncodeCheckerOwed).
+func checkerOwed(t *testing.T, number int, state, text string) (string, []byte) {
+	t.Helper()
+	key, err := delivery.CheckerOwedKey("novox/mesh-delivery", number, headA)
+	if err != nil {
+		t.Fatal(err)
+	}
+	v, err := delivery.EncodeCheckerOwed(delivery.Owed{Act: delivery.OwedStatus, Context: delivery.StatusContextCheck, State: state, Text: text, Target: "https://view.example/checks/g.0123456789ab"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return key, v
+}
+
+func TestTheCheckersStatusIsSetOncePerRevisionAndAKeyOfTheGateIsNotItsKey(t *testing.T) { // 1683/AC5 (ADR 0484 clause 2)
+	f := &forgeFake{}
+	p, _, done, _ := newPerformer(f)
+	key, v := checkerOwed(t, 12, "success", "pass aaaaaaaaaaaa on bbbbbbbbbbbb")
+	p.checkOwed(context.Background(), key, 3, v)
+	p.checkOwed(context.Background(), key, 3, v)
+	if len(f.calls) != 1 || f.calls[0].key != "gitea.gitea_commit_status" ||
+		f.calls[0].body != `{"context":"mesh/check","description":"pass aaaaaaaaaaaa on bbbbbbbbbbbb","owner":"novox","repo":"mesh-delivery","sha":"`+headA+`","state":"success","target_url":"https://view.example/checks/g.0123456789ab"}` {
+		t.Fatalf("calls = %+v", f.calls)
+	}
+	p.checkOwed(context.Background(), key, 4, v)
+	if len(f.calls) != 2 {
+		t.Errorf("a new revision was not performed: %+v", f.calls)
+	}
+	if _, ok := done["check."+key]; !ok {
+		t.Errorf("revision kept under %v, want check.%s", done, key)
+	}
+	// The gate's own owed bookkeeping is another key: the same owed key seen in the gate's bucket is its own act.
+	if _, ok := done["owed."+key]; ok {
+		t.Errorf("the checker's status was kept under the gate's key: %v", done)
+	}
+}
+
+func TestAnythingButTheCheckersStatusInItsBucketIsLeft(t *testing.T) { // ADR 0484 clause 2: the checker owes one act
+	f := &forgeFake{}
+	p, _, done, logs := newPerformer(f)
+	// A comment, and a status of another context: the SDK refuses both to the checker's encoder, so they are written raw.
+	commentKey, commentValue := owedKV(t, "novox/mesh-delivery", 12, "comment.1", delivery.Owed{Act: delivery.OwedComment, Text: "hello"})
+	gateKey, gateValue := owedKV(t, "novox/mesh-delivery", 12, "status=mesh/merge-gate",
+		delivery.Owed{Act: delivery.OwedStatus, Context: "mesh/merge-gate", State: "success", Text: "x", Target: "https://x.example"})
+	p.checkOwed(context.Background(), commentKey, 1, commentValue)
+	p.checkOwed(context.Background(), gateKey, 1, gateValue)
+	if len(f.calls) != 0 {
+		t.Errorf("the forge was called: %+v", f.calls)
+	}
+	if !strings.Contains(logs.String(), commentKey) || !strings.Contains(logs.String(), gateKey) || len(done) != 2 {
+		t.Errorf("log %q, kept %v: both keys are named and kept so they are not tried again", logs.String(), done)
+	}
+}
@@ -30,6 +30,10 @@ import (
 // The gate's buckets mesh-delivery-gate_merges and mesh-delivery-gate_owed are read and watched (the manifest's reads), the
 // bucket performed is the bridge's own (its state), and the five forge tools of the gate's acts are invoked (issue 1341, 1342).
 //
+// The checker's owed bucket is read like the gate's (reads) and the checker's stream checks is heard like EVENTS is (consumes
+// mesh-delivery-checker.owed.written; ADR 0484 clause 2): those entries are written by analogy with the ones the controller
+// composes for the gate's buckets and for the EVENTS consumer, not taken from a composed file.
+//
 // The lists are what mesh-controller's broker.PermissionsFor answers (internal/broker/nats.go:577) for a module principal
 // with the manifest of module.json: consumes the three gitea.pull events, invokes gitea.gitea_open_pulls,
 // gitea.gitea_commit_trees and gitea.gitea_get_file, state heads, and the stream forge; `**` is written `>` on the wire (modstreams.go
@@ -104,6 +108,14 @@ accounts {
            "mesh.mod.gitea.tool.gitea_add_comment"
            "mesh.mod.gitea.tool.gitea_add_comment.*"
            "mesh.stream.mesh-delivery-forge-bridge.event.forge.>"
+            "$JS.ACK.CHECKS.n1_mesh-delivery-forge-bridge.>"
+            "$JS.API.CONSUMER.INFO.CHECKS.n1_mesh-delivery-forge-bridge"
+            "$JS.API.CONSUMER.MSG.NEXT.CHECKS.n1_mesh-delivery-forge-bridge"
+            "$JS.API.CONSUMER.CREATE.KV_mesh-delivery-checker_owed.>"
+            "$JS.API.CONSUMER.DELETE.KV_mesh-delivery-checker_owed.>"
+            "$JS.API.DIRECT.GET.KV_mesh-delivery-checker_owed.>"
+            "$JS.API.STREAM.INFO.KV_mesh-delivery-checker_owed"
+            "$JS.FC.KV_mesh-delivery-checker_owed.>"
          ] }
          subscribe { allow: [
            "_INBOX.n1.mesh-delivery-forge-bridge.>"
@@ -205,6 +217,15 @@ func startBed(t *testing.T, openReply string, prepare func(ctx context.Context,
 	if _, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: "FORGE", Subjects: []string{"mesh.stream.mesh-delivery-forge-bridge.event.forge.>"}}); err != nil {
 		t.Fatal(err)
 	}
+	// The checker's stream checks and the bridge's durable consumer on its owed.written event; the checker's owed bucket is made
+	// only by the test that needs it, as when the checker is assigned after the bridge started.
+	if _, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: "CHECKS", Subjects: []string{"mesh.stream.mesh-delivery-checker.event.>"}}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := js.CreateOrUpdateConsumer(ctx, "CHECKS", jetstream.ConsumerConfig{Durable: "n1_mesh-delivery-forge-bridge", AckPolicy: jetstream.AckExplicitPolicy,
+		FilterSubjects: []string{"mesh.stream.mesh-delivery-checker.event.owed.written"}}); err != nil {
+		t.Fatal(err)
+	}
 	// The bridge's state bucket, made by the controller from the manifest's state entry before the process starts.
 	if _, err := js.CreateKeyValue(ctx, jetstream.KeyValueConfig{Bucket: headsBucket, History: 1}); err != nil {
 		t.Fatal(err)
@@ -706,3 +727,65 @@ func forgeMerged(t *testing.T, b *bed) []string {
 }

 func sha256Sum(b []byte) []byte { s := sha256.Sum256(b); return s[:] }
+
+// TestBridgePerformsTheCheckersStatusOncePerRevisionOfItsOwedKey: the checker's owed bucket is made after the bridge started;
+// the checker writes the status mesh/check it owes on a head (the SDK's CheckerOwedKey and EncodeCheckerOwed, which the checker
+// itself writes with) and says so on its stream; the bridge sets the status on the forge within 10 s, with the context
+// mesh/check, the state and the line; the same revision is not set again, a new revision is (ADR 0484 clause 2).
+func TestBridgePerformsTheCheckersStatusOncePerRevisionOfItsOwedKey(t *testing.T) { // 1683/AC5, ADR 0484 §2
+	b := startBed(t, `{"result":{"pulls":[]}}`, nil)
+	calls := make(chan string, 8)
+	sub, err := b.ctl.Subscribe("mesh.mod.gitea.tool.gitea_commit_status", func(m *nats.Msg) {
+		calls <- string(m.Data)
+		_ = m.Respond([]byte(`{"result":{},"node":"n0"}`))
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = sub.Unsubscribe() })
+	if err := b.ctl.Flush(); err != nil {
+		t.Fatal(err)
+	}
+	kv, err := b.js.CreateKeyValue(b.ctx, jetstream.KeyValueConfig{Bucket: delivery.CheckerOwedBucket, History: delivery.CheckerOwedHistory})
+	if err != nil {
+		t.Fatal(err)
+	}
+	key, err := delivery.CheckerOwedKey("novox/mesh-delivery", 12, head)
+	if err != nil {
+		t.Fatal(err)
+	}
+	put := func(state, text string) {
+		v, err := delivery.EncodeCheckerOwed(delivery.Owed{Act: delivery.OwedStatus, Context: delivery.StatusContextCheck, State: state, Text: text, Target: "https://view.example/checks/g.0123456789ab"})
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := kv.Put(b.ctx, key, v); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := b.js.Publish(b.ctx, owedWrittenSubject, []byte(`{"key":"`+key+`"}`)); err != nil {
+			t.Fatal(err)
+		}
+	}
+	next := func() string {
+		select {
+		case got := <-calls:
+			return got
+		case <-time.After(10 * time.Second):
+			t.Fatal("the status was not set within 10 s")
+		}
+		return ""
+	}
+	put("pending", "checking 0123456789ab on aaaaaaaaaaaa")
+	if got := next(); !strings.Contains(got, `"context":"mesh/check"`) || !strings.Contains(got, `"state":"pending"`) || !strings.Contains(got, `"sha":"`+head+`"`) || !strings.Contains(got, `"repo":"mesh-delivery"`) {
+		t.Fatalf("first call = %s", got)
+	}
+	put("success", "pass 0123456789ab on aaaaaaaaaaaa | unit 2 run, 3 kept")
+	if got := next(); !strings.Contains(got, `"state":"success"`) || !strings.Contains(got, "unit 2 run, 3 kept") {
+		t.Fatalf("second call = %s", got)
+	}
+	select {
+	case extra := <-calls:
+		t.Errorf("a third call was made: %s", extra)
+	case <-time.After(500 * time.Millisecond):
+	}
+}
@@ -0,0 +1,82 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"strings"
+	"sync"
+
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// checksStream is the stream the checker carries its events on, as the bus names it (declared by the checker as the stream
+// checks, heard by this module through consumes; novox/hq ADR 0484 clause 2).
+const checksStream = "CHECKS"
+
+// owedWrittenSubject is the subject of the checker's owed.written event.
+const owedWrittenSubject = "mesh.stream." + delivery.CheckerModule + ".event.owed.written"
+
+// lateWatch watches a bucket that may be made after the bridge started: the checker's owed bucket. The bridge holds no timer
+// (ADR 0437 §8), so it watches the bucket where it exists at start, and otherwise when the checker says it wrote a status
+// (owed.written, handled by Written).
+type lateWatch struct {
+	ctx context.Context
+	js  interface {
+		KeyValue(ctx context.Context, bucket string) (jetstream.KeyValue, error)
+	}
+	bucket  string
+	react   func(ctx context.Context, key string, rev uint64, value []byte)
+	logger  *log.Logger
+	errs    chan error
+	mu      sync.Mutex
+	watched bool
+}
+
+// ensure starts the watch if the bucket exists and is not watched.
+func (w *lateWatch) ensure() error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	if w.watched {
+		return nil
+	}
+	kv, err := w.js.KeyValue(w.ctx, w.bucket)
+	switch {
+	case errors.Is(err, jetstream.ErrBucketNotFound):
+		w.logger.Printf("the bucket %s does not exist yet: it is watched when the checker says it wrote a status", w.bucket)
+		return nil
+	case err != nil:
+		return fmt.Errorf("the bucket %s: %w", w.bucket, err)
+	}
+	w.watched = true
+	go func() {
+		w.errs <- watch(w.ctx, kv, func(key string, rev uint64, value []byte) {
+			hctx, cancel := context.WithTimeout(w.ctx, syncDeadline)
+			defer cancel()
+			w.react(hctx, key, rev, value)
+		})
+	}()
+	return nil
+}
+
+// Written takes one owed.written event of the checker in: its bucket is watched if it is not. A subject that is not the
+// checker's is terminated; a failure stays unacknowledged, and the server delivers it again.
+func (w *lateWatch) Written(m interface {
+	Subject() string
+	Ack() error
+	Term() error
+}) {
+	if !strings.HasPrefix(m.Subject(), owedWrittenSubject) {
+		w.logger.Printf("%s: not the checker's owed.written, dropped", m.Subject())
+		_ = m.Term()
+		return
+	}
+	if err := w.ensure(); err != nil {
+		w.logger.Printf("%s: left for redelivery: %v", m.Subject(), err)
+		return
+	}
+	_ = m.Ack()
+}
@@ -202,7 +202,7 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		return fmt.Errorf("the bucket %s: %w", performedBucket, err)
 	}
 	perf := &performer{call: call, pub: rec, done: kvRevisions{performedKV}, logger: logger}
-	watching := make(chan error, 2)
+	watching := make(chan error, 3)
 	for _, w := range []struct {
 		bucket string
 		react  func(ctx context.Context, key string, rev uint64, value []byte)
@@ -225,6 +225,24 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 			})
 		}()
 	}
+	// The checker's statuses (mesh/check, unrequired until release R4f): its bucket is made when the checker is assigned, which
+	// may be after the bridge started, and the bridge holds no timer; the checker says on its stream each time it wrote a
+	// status, and the bucket is then watched (late.go).
+	late := &lateWatch{ctx: ctx, js: js, bucket: delivery.CheckerOwedBucket, react: perf.checkOwed, logger: logger, errs: watching}
+	if err := late.ensure(); err != nil {
+		return err
+	}
+	switch ccons, err := js.Consumer(ctx, checksStream, cred.Node+"_"+cred.Module); {
+	case err != nil:
+		logger.Printf("the consumer %s_%s on %s does not exist yet, so the checker's statuses are not heard until the bridge starts again: %v", cred.Node, cred.Module, checksStream, err)
+	default:
+		cc, err := ccons.Consume(func(m jetstream.Msg) { late.Written(m) },
+			jetstream.ConsumeErrHandler(func(_ jetstream.ConsumeContext, err error) { logger.Printf("hearing the bus: %v", err) }))
+		if err != nil {
+			return err
+		}
+		defer cc.Stop()
+	}
 	if err := said(ctx); err != nil {
 		return err
 	}
@@ -86,10 +86,10 @@ func TestManifestDeclarations(t *testing.T) { // 1235/AC1
 	if !reflect.DeepEqual(m.Streams, []stream{{Name: "forge", Events: []string{"forge.**"}}}) {
 		t.Errorf("streams = %+v", m.Streams)
 	}
-	if want := []string{"gitea.pull.closed", "gitea.pull.merged", "gitea.pull.updated"}; !reflect.DeepEqual(sorted(m.Consumes), want) {
+	if want := []string{"gitea.pull.closed", "gitea.pull.merged", "gitea.pull.updated", "mesh-delivery-checker.owed.written"}; !reflect.DeepEqual(sorted(m.Consumes), want) {
 		t.Errorf("consumes = %v, want %v", m.Consumes, want)
 	}
-	if want := []string{"mesh-delivery-gate.merges", "mesh-delivery-gate.owed"}; !reflect.DeepEqual(sorted(m.Reads), want) {
+	if want := []string{"mesh-delivery-checker.owed", "mesh-delivery-gate.merges", "mesh-delivery-gate.owed"}; !reflect.DeepEqual(sorted(m.Reads), want) {
 		t.Errorf("reads = %v, want %v", m.Reads, want)
 	}
 	if want := []string{"gitea.gitea_add_comment", "gitea.gitea_commit_status", "gitea.gitea_commit_trees", "gitea.gitea_delivery_view",
@@ -5,7 +5,8 @@
  "consumes": [
    "gitea.pull.updated",
    "gitea.pull.merged",
-    "gitea.pull.closed"
+    "gitea.pull.closed",
+    "mesh-delivery-checker.owed.written"
  ],
  "streams": [
    { "name": "forge", "events": ["forge.**"] }
@@ -15,6 +16,7 @@
    { "name": "performed", "history": 1 }
  ],
  "reads": [
+    "mesh-delivery-checker.owed",
    "mesh-delivery-gate.merges",
    "mesh-delivery-gate.owed"
  ],
@@ -15,9 +15,9 @@ import (
 	"mesh-delivery-indexer/internal/index"
 )

-// PreviewsStream is the stream the checker carries its preview.written event on, as the bus names it (declared by the
-// checker as the stream previews, heard by this module through consumes; novox/hq ADR 0484 clause 3).
-const PreviewsStream = "PREVIEWS"
+// PreviewsStream is the stream the checker carries its events on, as the bus names it (declared by the
+// checker as the stream checks, heard by this module through consumes; novox/hq ADR 0484 clause 3).
+const PreviewsStream = "CHECKS"

 // previewWrittenSubject is the subject of the checker's preview.written event.
 const previewWrittenSubject = "mesh.stream." + delivery.CheckerModule + ".event.preview.written"