Merge pull request 'Give the indexer a new build: its last build's program never reached the artifact store, so novox cannot apply (issue 1933)' (#32) from fix/1933-rebuild-indexer into main

Reviewed-on: #32

modules/mesh-delivery-assigner/cmd/mesh-delivery-assigner/integration_test.go

@@ -181,8 +181,10 @@ func TestAChangeIsComposedOnTheBus(t *testing.T) {
 	b.putJSON(t, provider.AssignmentsBucket, "ace.other", []byte(`{"node":"ace","module":"other","build":"build-2"}`))
 	heads := []delivery.Head{{Repository: "novox/web", Number: 7, Head: strings.Repeat("2", 40)}}
 	hash, _ := delivery.HeadsHash(heads)
-	cand, err := delivery.EncodeCandidate(delivery.Candidate{Group: "feat/x", HeadsHash: hash, Pulls: []delivery.CandidatePull{{Head: heads[0],
-		Modules: []string{"web"}, Fps: map[string]delivery.CandidateModule{"web": {FP2: delivery.SourcePrefix2 + strings.Repeat("b", 64), Manifest: changed}}}}})
+	// 1927/AC1: the candidate carries the fingerprint set the SDK computes, as the indexer writes it.
+	pulls := []delivery.CandidatePull{{Head: heads[0],
+		Modules: []string{"web"}, Fps: map[string]delivery.CandidateModule{"web": {FP2: delivery.SourcePrefix2 + strings.Repeat("b", 64), Manifest: changed}}}}
+	cand, err := delivery.EncodeCandidate(delivery.Candidate{Group: "feat/x", HeadsHash: hash, Pulls: pulls, FPSet: delivery.FingerprintSet(pulls)})
 	if err != nil {
 		t.Fatal(err)
 	}

modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go

@@ -179,7 +179,11 @@ type bed struct {
 // startBed starts the bus, the buckets the controller makes from the builder's and the build modules' manifests, the
 // build modules' streams and the builder's durable consumers on them, two nodes' toolchains, the indexer's manifests, and
 // the fake build modules. It runs no builder.
-func startBed(t *testing.T) *bed {
+func startBed(t *testing.T) *bed { return startBedWith(t, false) }
+
+// startBedWith is startBed with the nodes' capacity 0 from the start when closed: a puller that reads its capacity before a
+// test could close the nodes may be in a pull already and takes the first ask put (issue 1928).
+func startBedWith(t *testing.T, closed bool) *bed {
 	dir, err := os.MkdirTemp(os.Getenv("TMPDIR"), "b")
 	if err != nil {
 		t.Fatal(err)
@@ -243,6 +247,7 @@ func startBed(t *testing.T) *bed {
 	b.builds = mk(delivery.BuilderBuildsBucket, delivery.BuilderBuildsHistory)
 	b.instances = mk(instancesBucket, 1)
 	b.fake = &fakeBuildModules{js: js, ctx: ctx, calls: map[string]int{}}
+	b.fake.closed.Store(closed)
 	b.fake.serve(t, "mesh-build-go", "n1", "n2")
 	b.fake.serve(t, "mesh-build-node", "n1", "n2")
 	b.fake.serve(t, "mesh-build-image", "n1") // the image build module runs on n1 only
@@ -781,8 +786,7 @@ func (b *bed) asksPut(t *testing.T, nc *nats.Conn) func() []delivery.StepAsk {
 // 1887/AC3: a builder that started again while its asks waited in the streams (no node had a free slot) puts no second
 // ask: it waits for the asks its building key names, and the key is done once a node took them.
 func TestARestartedBuilderPutsNoSecondAsk(t *testing.T) {
-	b := startBed(t)
-	b.fake.closed.Store(true)
+	b := startBedWith(t, true) // 1928/AC1: no node can take an ask from the start, so no pull in hand takes the first one
 	b.module(t, "netcheck", "catalogue-a67f0196-netcheck.module.json", "modules/netcheck")
 	sub, err := nats.Connect(b.srvURL, nats.UserInfo("ctl", "pw"))
 	if err != nil {
@@ -792,11 +796,13 @@ func TestARestartedBuilderPutsNoSecondAsk(t *testing.T) {
 	asked := b.asksPut(t, sub)
 	b.start(t, "n1", nil)
 	v := b.await(t, "netcheck", func(v delivery.BuilderBuild) bool { return v.State == delivery.BuildBuilding && len(v.Asks) == 2 })
-	for deadline := time.Now().Add(5 * time.Second); len(asked()) < 2 && time.Now().Before(deadline); time.Sleep(20 * time.Millisecond) {
+	for deadline := time.Now().Add(20 * time.Second); len(asked()) < 2; time.Sleep(20 * time.Millisecond) {
+		if time.Now().After(deadline) {
+			t.Fatalf("asks put = %+v within 20 s, want the two the key names", asked())
+		}
 	}
 	b.stop()
 	b.start(t, "n1", nil) // the same builder, started again, while both asks wait
-	time.Sleep(500 * time.Millisecond)
 	b.fake.open()
 	done := b.await(t, "netcheck", isState(delivery.BuildDone))
 	if got := asked(); len(got) != 2 {

modules/mesh-delivery-checker/cmd/mesh-delivery-checker/integration_test.go

@@ -10,6 +10,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"sort"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -81,6 +82,9 @@ type fakeBuildModules struct {
 	mu       sync.Mutex
 	calls    map[string]int // by `<module>.<tool>`
 	testTool *testing.T
+	// beside is, by workspace, the siblings the fetch placed in it as `<owner/repo> <commit>`, sorted: a digest echoes them
+	// (1929/AC2; mesh-sdk buildstep.besideOf), or the level runs whole and keeps nothing.
+	beside map[string][]string
 }
 
 func (f *fakeBuildModules) count(tool string) int {
@@ -100,10 +104,30 @@ func (f *fakeBuildModules) result(t *testing.T, tool string, args map[string]any
 		}
 		fetched := readCaptured(t, name)
 		fetched["commit"], fetched["base"] = args["commit"], args["base"]
+		var refs []struct {
+			Repository string `json:"repository"`
+			Commit     string `json:"commit"`
+		}
+		raw, _ := json.Marshal(args["beside"])
+		_ = json.Unmarshal(raw, &refs)
+		var lines []string
+		for _, r := range refs {
+			lines = append(lines, r.Repository+" "+r.Commit)
+		}
+		sort.Strings(lines)
+		f.mu.Lock()
+		if f.beside == nil {
+			f.beside = map[string][]string{}
+		}
+		f.beside[fmt.Sprint(fetched["workspace"])] = lines
+		f.mu.Unlock()
 		v = fetched
 	case strings.HasSuffix(tool, "_digest"):
 		d := map[string]string{"unit": digU, "integration": digI}[level]
-		v = map[string]any{"level": level, "packages": map[string]string{"fixture/slow": d}}
+		f.mu.Lock()
+		beside := f.beside[fmt.Sprint(args["workspace"])]
+		f.mu.Unlock()
+		v = map[string]any{"level": level, "packages": map[string]string{"fixture/slow": d}, "beside": beside}
 	case strings.HasSuffix(tool, "_test"):
 		r := readCaptured(t, "go-test-slow")
 		r["level"] = level
@@ -288,6 +312,15 @@ func startBed(t *testing.T) *bed {
 		}
 		b.buckets[name] = kv
 	}
+	// 1929/AC1: the indexer's value of the repository's module, with no TypeScript manifest, so the Go build module alone
+	// judges the repository (an unknown repository is judged by both, issue 1887 A12).
+	known, err := delivery.EncodeModule(delivery.Module{Repository: repo, Commit: trunk, Path: "modules/m", None2: "the fingerprint is computed with its chain"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := b.buckets[delivery.ModulesBucket].Put(ctx, "m", known); err != nil {
+		t.Fatal(err)
+	}
 	b.setOnline(t, "n1", true)
 	for _, module := range []string{"mesh-build-go", "mesh-build-node"} {
 		b.setHealth(t, "n1", module)
@@ -436,7 +469,7 @@ func (b *bed) owed(t *testing.T, number int, head, state string) delivery.Owed {
 // TestCheckerJudgesACandidateAndOwesItsStatus: a candidate the indexer wrote, one pull request of mesh-delivery, is fetched
 // merged onto the trunk the gate names, digested and tested at both levels on the node, kept, previewed; the verdict passes
 // with the counts of both levels and the composition not run, and the status mesh/check is owed on the head as success.
-func TestCheckerJudgesACandidateAndOwesItsStatus(t *testing.T) { // N6/AC5, 1300/AC5, 1445/AC1
+func TestCheckerJudgesACandidateAndOwesItsStatus(t *testing.T) { // N6/AC5, 1300/AC5, 1445/AC1, 1929/AC1
 	b := startBed(t)
 	key := b.candidate(t, "feat/x", pull(repo, 7, head1))
 	b.start(t, nil)
@@ -476,7 +509,7 @@ func TestCheckerJudgesACandidateAndOwesItsStatus(t *testing.T) { // N6/AC5, 1300
 
 // TestACheckOfEqualInputsRunsNothing: a second candidate (another head, the same digests) is checked with every package
 // taken from the first's kept verdicts: no test step runs and no second kept key appears.
-func TestACheckOfEqualInputsRunsNothing(t *testing.T) { // 1287/AC5, 1288/AC6
+func TestACheckOfEqualInputsRunsNothing(t *testing.T) { // 1287/AC5, 1288/AC6, 1929/AC2
 	b := startBed(t)
 	first := b.candidate(t, "feat/x", pull(repo, 7, head1))
 	b.start(t, nil)
@@ -574,7 +607,7 @@ func TestACheckLeftRunningIsTakenOverWhenTheCheckerStarts(t *testing.T) { // N6/
 
 // TestAMemberNamingAMeshSDKCommitOffTheTrunkFailsNamingTheCommit: the go.mod the forge answers names a commit that main does not
 // hold; the verdict fails naming the member and the commit and no test runs (ADR 0484 clause 9).
-func TestAMemberNamingAMeshSDKCommitOffTheTrunkFailsNamingTheCommit(t *testing.T) { // 1624/AC2
+func TestAMemberNamingAMeshSDKCommitOffTheTrunkFailsNamingTheCommit(t *testing.T) { // 1624/AC2, 1929/AC3
 	b := startBed(t)
 	b.stalePin.Store(true)
 	key := b.candidate(t, "feat/x", pull(repo, 7, head1))
@@ -583,9 +616,7 @@ func TestAMemberNamingAMeshSDKCommitOffTheTrunkFailsNamingTheCommit(t *testing.T
 	if v.State != delivery.VerdictFail || !strings.Contains(v.Failed.Words, "9aaa5c80ac5c") || !strings.Contains(v.Failed.Words, repo+"#7") {
 		t.Fatalf("verdict = %+v", v)
 	}
-	if n := b.fake.count("mesh-build-go.build_go_test"); n != 0 {
-		t.Errorf("%d test steps ran after a stale pin", n)
-	}
+	// 1929/AC3: no assertion that no test ran: one ask runs fetch, digest and tests (ADR 0525 §3).
 }
 
 // triesStore is the tries bucket as the tools write it.
@@ -671,7 +702,7 @@ func TestTheCheckerSaysOwedReadableOnTheBus(t *testing.T) { // R2-1
 		break
 	}
 	if said.Module != "mesh-delivery-checker" || said.Node != "n1" || !said.Keeps("owed") || !said.Readable("owed") ||
-		!said.Readable("previews") || !said.Readable("verdicts") || said.Readable("kept") || said.Readable("tries") || len(said.States) != 5 {
-		t.Fatalf("the checker said %+v, want its five states with owed, previews and verdicts readable", said)
+		!said.Readable("previews") || !said.Readable("verdicts") || !said.Readable("kept") || said.Readable("tries") || len(said.States) != 5 {
+		t.Fatalf("the checker said %+v, want its five states with kept, owed, previews and verdicts readable (1929/AC4; 1887 A5b)", said)
 	}
 }

modules/mesh-delivery-checker/go.mod

@@ -3,7 +3,7 @@ module mesh-delivery-checker
 go 1.26.0
 
 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023150321-a2c813a6b468
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023213200-403a5d72ab93
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0
 )

modules/mesh-delivery-checker/go.sum

@@ -1,5 +1,5 @@
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023150321-a2c813a6b468 h1:UcMee+IV2ii5E4dRZdQUaSaeh9IedTFYumuQbBiB0k0=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023150321-a2c813a6b468/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023213200-403a5d72ab93 h1:FAiFY2KBKEoZSH49OZTt7/zRBIQxyl5g/KhYrpggbN4=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261023213200-403a5d72ab93/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=
 github.com/google/go-tpm v0.9.8 h1:slArAR9Ft+1ybZu0lBwpSmpwhRXaa85hWtMinMyRAWo=

modules/mesh-delivery-checker/internal/check/beside.go

@@ -26,7 +26,7 @@ const (
 // checks/deps). Which commit of each is besideCommit's rule.
 var besideRules = map[string][]string{
 	controllerRepo:        {catalogueRepository, nodeEngineRepo, SDKRepository},
-	nodeEngineRepo:        {catalogueRepository, SDKRepository},
+	nodeEngineRepo:        {catalogueRepository, SDKRepository, controllerRepo},
 	SDKRepository:         {catalogueRepository, nodeEngineRepo},
 	catalogueRepository:   {SDKRepository, controllerRepo},
 	"novox/mesh-delivery": {SDKRepository, catalogueRepository},

modules/mesh-delivery-checker/internal/check/digestform_test.go

@@ -0,0 +1,83 @@
+package check
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// 1930/AC3: given a check ask whose stored end keeps the digest's packages as a list of {package, digest} (issue 1930),
+// or one stored before it with the packages a map keyed by package path, when the same heads are checked a second time,
+// then the kept verdicts the first check wrote are read from it: every package it passed is kept, none run again.
+func TestKeptVerdictsAreReadFromTheDigestsListForm(t *testing.T) {
+	for _, tc := range []struct {
+		name string
+		old  bool
+	}{{"the list form", false}, {"a map stored before issue 1930", true}} {
+		t.Run(tc.name, func(t *testing.T) {
+			b := newBench(t)
+			var stored []string
+			b.asks.Answer = func(a delivery.StepAsk) delivery.Step {
+				s := b.answer(a)
+				if tc.old && s.State == delivery.StepPassed {
+					s.Result = oldDigestForm(t, s.Result)
+				}
+				stored = append(stored, string(s.Result))
+				return s
+			}
+			first := b.judge(t, caseOf(t, pullOf(repoA, 7, head1))).Verdict
+			u := first.Levels[delivery.LevelUnit]
+			if first.State != delivery.VerdictPass || u.Run == 0 || u.Kept != 0 {
+				t.Fatalf("the first check = %+v", first)
+			}
+			if len(stored) == 0 {
+				t.Fatal("no ask's end was stored")
+			}
+			list := strings.Contains(stored[0], `"packages":[{"package":"fixture/slow"`)
+			if list == tc.old || strings.Contains(stored[0], `"fixture/slow":"`) != tc.old {
+				t.Fatalf("the stored end is not in the form under test: %s", stored[0])
+			}
+			b.steps.calls = nil
+			second := b.judge(t, caseOf(t, pullOf(repoA, 7, head1))).Verdict
+			if s := second.Levels[delivery.LevelUnit]; second.State != delivery.VerdictPass || s.Kept != u.Run || s.Run != 0 {
+				t.Fatalf("the second check's unit level = %+v, want %d kept and none run", s, u.Run)
+			}
+			if n := len(b.steps.tool("test")); n != 0 {
+				t.Errorf("%d test steps ran on the second check", n)
+			}
+		})
+	}
+}
+
+// oldDigestForm rewrites a check answer's level digests to the form stored before issue 1930: packages as a map keyed by
+// package path.
+func oldDigestForm(t *testing.T, result json.RawMessage) json.RawMessage {
+	t.Helper()
+	var a struct {
+		Fetch  json.RawMessage  `json:"fetch"`
+		Levels []map[string]any `json:"levels"`
+	}
+	if err := json.Unmarshal(result, &a); err != nil {
+		t.Fatal(err)
+	}
+	for _, l := range a.Levels {
+		d, ok := l["digest"].(map[string]any)
+		if !ok {
+			continue
+		}
+		m := map[string]any{}
+		list, _ := d["packages"].([]any)
+		for _, p := range list {
+			pd := p.(map[string]any)
+			m[pd["package"].(string)] = pd["digest"]
+		}
+		d["packages"] = m
+	}
+	raw, err := json.Marshal(a)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return raw
+}

modules/mesh-delivery-checker/internal/check/failure_words_test.go

@@ -0,0 +1,73 @@
+package check
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// The failure the build module reported for group r4g on 2026-10-23: the test logged a line, then failed with a multi-line
+// t.Fatalf. Its output is what the build module now sends (its last lines, with the error line as Cause).
+func fatalAfterLog() Failure {
+	return Failure{
+		Package: "github.com/novox/mesh-controller/internal/broker", Test: "TestTheCataloguesDerivedSubjectsMeet",
+		Cause: "3 subscription(s) derive to a subject no emitter owns:",
+		Output: "    agreement_catalogue_test.go:130: judged against /var/lib/mesh-build-go-work/id/beside/mesh-catalog as cloned\n" +
+			"    agreement_catalogue_test.go:186: 3 subscription(s) derive to a subject no emitter owns:\n" +
+			"          a.b.c\n          d.e.f\n          g.h.i\n--- FAIL: TestTheCataloguesDerivedSubjectsMeet (0.00s)",
+	}
+}
+
+func TestAFailedTestsVerdictKeepsItsWholeFailureMessage(t *testing.T) { // 1901/AC1
+	v := levelFailure(&target{}, "unit", Tested{Failed: []Failure{fatalAfterLog()}})
+	for _, want := range []string{"3 subscription(s) derive to a subject no emitter owns:", "a.b.c", "d.e.f", "g.h.i"} {
+		if !strings.Contains(v.Failed.Words, want) {
+			t.Errorf("words lack %q: %q", want, v.Failed.Words)
+		}
+	}
+	if len(v.Failed.Words) > MaxWords+200 {
+		t.Errorf("words are %d bytes, bound %d", len(v.Failed.Words), MaxWords)
+	}
+}
+
+func TestTheStatusLineNamesTheFailureNotTheFirstLoggedLine(t *testing.T) { // 1901/AC2
+	v := levelFailure(&target{}, "unit", Tested{Failed: []Failure{fatalAfterLog()}})
+	got := firstFailed(*v)
+	if !strings.Contains(got, "3 subscription(s) derive to a subject no emitter owns:") || strings.Contains(got, "judged against") || strings.Contains(got, "\n") {
+		t.Errorf("firstFailed = %q", got)
+	}
+	// With no cause told apart (an older build module), the words still start at the first line, as before.
+	f := fatalAfterLog()
+	f.Cause = ""
+	v = levelFailure(&target{}, "unit", Tested{Failed: []Failure{f}})
+	if !strings.HasPrefix(v.Failed.Words, "agreement_catalogue_test.go:130") {
+		t.Errorf("words = %q", v.Failed.Words)
+	}
+}
+
+func TestWordsLongerThanTheBoundKeepTheirLastLines(t *testing.T) { // 1901/AC1
+	f := Failure{Output: strings.Repeat("log line of some length\n", 500) + "the cause is here"}
+	v := levelFailure(&target{}, "unit", Tested{Failed: []Failure{f}})
+	if !strings.HasSuffix(v.Failed.Words, "the cause is here") || len(v.Failed.Words) > MaxWords+200 {
+		t.Errorf("%d bytes, ends %q", len(v.Failed.Words), v.Failed.Words[len(v.Failed.Words)-30:])
+	}
+	_ = delivery.VerdictFail
+}
+
+// An older build module sends no "cause": its answer is still accepted and the verdict's words are its output, as before.
+func TestAnOlderBuildModulesFailureIsAcceptedWithItsWholeOutput(t *testing.T) { // 1901/AC3
+	old := `{"package":"p","test":"TestX","output":"x_test.go:1: logged\nx_test.go:2: the old kept lines"}`
+	var f Failure
+	if err := json.Unmarshal([]byte(old), &f); err != nil || f.Cause != "" {
+		t.Fatalf("1901/AC3: err = %v, cause = %q", err, f.Cause)
+	}
+	v := levelFailure(&target{}, "unit", Tested{Failed: []Failure{f}})
+	if v.Failed.Words != "x_test.go:1: logged\nx_test.go:2: the old kept lines" {
+		t.Errorf("1901/AC3: words = %q", v.Failed.Words)
+	}
+	if got := firstFailed(*v); !strings.Contains(got, "logged") || strings.Contains(got, "\n") {
+		t.Errorf("1901/AC3: status = %q", got)
+	}
+}

modules/mesh-delivery-checker/internal/check/judge.go

@@ -447,13 +447,11 @@ func (st *state) level(ctx context.Context, t *target, la delivery.LevelAnswer)
 		return fail(t.node, fmt.Sprintf("the check of %s#%d answered the level %q, which is no level", t.pull.Repository, t.pull.Number, level)), 0
 	}
 	var digests map[string]string
-	if t.module == buildrun.GoBuildModule && len(la.Digest) > 0 {
-		var d Digested
-		if err := json.Unmarshal(la.Digest, &d); err == nil {
-			digests = d.Packages
-			if t.runner != "" {
-				t.judgedBy(d.JudgedBy) // the installed module judged it: the runner is not used again
-			}
+	if t.module == buildrun.GoBuildModule && la.Digest != nil {
+		// The packages come as a list, never keyed by a package path (issue 1930); an answer stored before reads too.
+		digests = la.Digest.Map()
+		if t.runner != "" {
+			t.judgedBy(la.Digest.JudgedBy) // the installed module judged it: the runner is not used again
 		}
 	}
 	if t.runner != "" && la.Judged != "" {
@@ -525,13 +523,35 @@ func failedName(f Failure) string {
 	return f.Package + "." + f.Test
 }
 
-// firstLine is the first non-empty line of a failure's output, shortened.
+// MaxWords is the most a failed test's words in a verdict hold (issue 1901). **The words keep the failure's last lines**,
+// where a test says why it failed: the first line is often something it logged before (the group r4g verdict kept a
+// "judged against" line and lost the t.Fatalf after it), and the 120 characters kept before cut a docker command's echo
+// before docker's own error. Four kilobytes holds a long message and is small beside a verdict's other parts.
+const MaxWords = 4096
+
+// failureWords is a failure's words: its output's last lines up to MaxWords, with the line the build module told apart as
+// the test's error first when the output does not start with it, so the first line of the words is the cause and the
+// status line, which is cut short, names it.
+func failureWords(f Failure) string {
+	out := strings.TrimSpace(f.Output)
+	if len(out) > MaxWords {
+		out = out[len(out)-MaxWords:]
+		// Start on a whole line, and a whole character.
+		if i := strings.IndexByte(out, '\n'); i >= 0 {
+			out = "... " + strings.TrimLeft(out[i:], "\n")
+		}
+		out = strings.ToValidUTF8(out, "")
+	}
+	if c := strings.TrimSpace(f.Cause); c != "" && !strings.HasPrefix(firstLine(out), c) {
+		out = c + "\n" + out
+	}
+	return out
+}
+
+// firstLine is the first non-empty line of a failure's words.
 func firstLine(s string) string {
 	for _, l := range strings.Split(s, "\n") {
 		if l = strings.TrimSpace(l); l != "" {
-			if len(l) > 120 {
-				l = l[:120]
-			}
 			return l
 		}
 	}
@@ -548,7 +568,7 @@ func levelFailure(t *target, level string, res Tested) *delivery.Verdict {
 		if t.module == buildrun.NodeBuildModule && f.Package == "" {
 			name = res.Module
 		}
-		v.Failed = delivery.FailedFirst{Test: level + ": " + name, Words: firstLine(f.Output)}
+		v.Failed = delivery.FailedFirst{Test: level + ": " + name, Words: failureWords(f)}
 	default:
 		why := res.Why
 		if why == "" {

modules/mesh-delivery-checker/internal/check/line.go

@@ -37,18 +37,21 @@ func firstFailed(v delivery.Verdict) string {
 	f := v.Failed
 	switch {
 	case f.Test != "":
-		if f.Words != "" {
-			return f.Test + ": " + f.Words
+		if w := firstWordsLine(f.Words); w != "" {
+			return f.Test + ": " + w
 		}
 		return f.Test
-	case f.Machine != "" && f.Words != "":
-		return f.Machine + ": " + f.Words
+	case f.Machine != "" && firstWordsLine(f.Words) != "":
+		return f.Machine + ": " + firstWordsLine(f.Words)
 	case f.Machine != "":
 		return f.Machine
 	}
-	return f.Words
+	return firstWordsLine(f.Words)
 }
 
+// firstWordsLine is the first line of a failure's words: the words are several lines (issue 1901) and the status line one.
+func firstWordsLine(w string) string { return firstLine(w) }
+
 // pieces are the parts of a line, from the most to the least needed.
 type pieces struct {
 	head, commits, counts, shortCounts, times, shortTimes, over, builds, composition, shortComposition, group string

modules/mesh-delivery-checker/internal/check/pins_test.go

@@ -244,6 +244,39 @@ func TestTheSiblingsAreWhereTheTestsStateThem(t *testing.T) { // review D2, ADR
 	}
 }
 
+// 1295/R4g: the node-engine's tests read the controller's manifest, so a mesh-host pull request has mesh-controller beside it:
+// at the group member's head when the group holds one, else at its trunk.
+func hostCase(t *testing.T, pulls ...delivery.CandidatePull) *Case {
+	t.Helper()
+	c, err := delivery.DecodeCandidate(candidateOf(t, "feat/x", pulls...))
+	if err != nil {
+		t.Fatal(err)
+	}
+	cs := CaseOf(c, map[string]string{"novox/mesh-host": trunkA, controllerRepo: trunkA2})
+	if cs == nil {
+		t.Fatal("no case")
+	}
+	return cs
+}
+
+func TestTheNodeEnginesTestsHaveTheControllerBesideThem(t *testing.T) {
+	const host = "novox/mesh-host"
+	b := newBench(t)
+	b.ex.Trunks = trunksOf(t, map[string]string{host: trunkA, controllerRepo: trunkA2, catalogueRepository: trunkS, SDKRepository: trunkS})
+	b.judge(t, hostCase(t, pullOf(host, 5, head1)))
+	if c := besideOf(t, b, host)[controllerRepo]; c.Commit != trunkA2 || c.Ref != "" {
+		t.Errorf("the controller beside the node-engine alone = %+v, want its trunk %s", c, trunkA2)
+	}
+	b = newBench(t)
+	b.ex.Trunks = trunksOf(t, map[string]string{host: trunkA, controllerRepo: trunkA2, catalogueRepository: trunkS, SDKRepository: trunkS})
+	b.ex.Forge = &fakeForge{goMods: map[string]string{controllerRepo + " go.mod " + head2: capturedGoMod(t, "cb54756c3865")},
+		onTrunk: map[string]bool{"cb54756c3865": true}}
+	b.judge(t, hostCase(t, pullOf(host, 5, head1), pullOf(controllerRepo, 9, head2)))
+	if c := besideOf(t, b, host)[controllerRepo]; c.Commit != head2 || c.Ref != "refs/pull/9/head" {
+		t.Errorf("the controller beside the node-engine in a group = %+v, want the member's head %s", c, head2)
+	}
+}
+
 func TestThePinOfTheControllerThatCannotBeReadFailsTheCheck(t *testing.T) { // review D2
 	b := newBench(t)
 	b.ex.Trunks = trunksOf(t, map[string]string{"novox/mesh-controller": trunkA})

modules/mesh-delivery-checker/internal/check/results.go

@@ -59,6 +59,8 @@ type Failure struct {
 	Package string `json:"package"`
 	Test    string `json:"test,omitempty"`
 	Output  string `json:"output,omitempty"`
+	// Cause is the first line of what the test reported as its error, when the build module told it apart (issue 1901).
+	Cause string `json:"cause,omitempty"`
 }
 
 // TestTime is one test and the seconds it took.

modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/integration_test.go

@@ -478,3 +478,74 @@ func TestAMergeOfMeshSDKChangingOnlyGoLeavesItsNamedTreeEqual(t *testing.T) {
 		t.Errorf("the new form moved: %q/%q, then %q/%q", first.FP2, first.None2, second.FP2, second.None2)
 	}
 }
+
+// TestIndexerJudgesAnUnreadableVerdictAgainAtStart: the modules bucket holds avahi as an older SDK wrote it, with the reason
+// 'the manifest cannot be read', the inputs the merge carried (the tree, the lock hash by file name) and the digest of its
+// manifest, which manifests.<digest> holds and the running SDK reads; the go toolchain is reported. Within 5 s of the start
+// and with no repository merge the value carries a fingerprint and no reason (issue 1923).
+func TestIndexerJudgesAnUnreadableVerdictAgainAtStart(t *testing.T) { // 1923/AC3
+	manifest, err := os.ReadFile("../../internal/index/testdata/catalogue-a67f0196-avahi.module.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	const goSum = "3b5028f0c1e9bde04dd766abd63eb5931bc516bae695cf46f00abcd8510b0381"
+	digest := delivery.ManifestDigest(manifest)
+	_, ctx, _, modules := startIndexer(t, func(context.Context, jetstream.KeyValue) {}, func(ctx context.Context, js jetstream.JetStream) {
+		mkey, err := delivery.ManifestsKey(digest)
+		if err != nil {
+			t.Fatal(err)
+		}
+		mdata, err := delivery.EncodeManifest(delivery.Manifest{Module: "avahi", JSON: string(manifest)})
+		if err != nil {
+			t.Fatal(err)
+		}
+		manifests, err := js.KeyValue(ctx, delivery.ManifestsBucket)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := manifests.Put(ctx, mkey, mdata); err != nil {
+			t.Fatal(err)
+		}
+		stale, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: "89abcdef0123456789abcdef0123456789abcdef", Path: "modules/avahi",
+			Manifest: digest, None2: "the manifest cannot be read: claims node-build-go, which is a seat in the mesh's own namespace that it does not define",
+			Inputs2: &delivery.KeptInputs2{Tree: "tree-avahi", Locks: map[string]string{"go.sum": goSum}}})
+		if err != nil {
+			t.Fatal(err)
+		}
+		held, err := js.KeyValue(ctx, delivery.ModulesBucket)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := held.Put(ctx, "avahi", stale); err != nil {
+			t.Fatal(err)
+		}
+		kv, err := js.CreateKeyValue(ctx, jetstream.KeyValueConfig{Bucket: delivery.ToolchainsBucket("mesh-build-go"), History: 1})
+		if err != nil {
+			t.Fatal(err)
+		}
+		key, err := delivery.ToolchainKey("n1", "go")
+		if err != nil {
+			t.Fatal(err)
+		}
+		value, err := delivery.EncodeToolchain(delivery.Toolchain{Language: "go", Version: "go1.27.1", Recipe: "1", At: time.Now()})
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := kv.Put(ctx, key, value); err != nil {
+			t.Fatal(err)
+		}
+	})
+	var got delivery.Module
+	for deadline := time.Now().Add(5 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
+		if e, err := modules.Get(ctx, "avahi"); err == nil {
+			if m, err := delivery.DecodeModule(e.Value()); err == nil {
+				if got = m; got.FP2 != "" {
+					break
+				}
+			}
+		}
+	}
+	if got.FP2 == "" || got.None2 != "" {
+		t.Errorf("avahi = fp2 %q none2 %q within 5 s of the start, want a fingerprint and no reason", got.FP2, got.None2)
+	}
+}

modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/main.go

@@ -2,6 +2,9 @@
 // bridge's messages on the stream FORGE and keeps the candidate groups (candidates.<group>): the pull requests that share
 // a branch, their heads and the modules each touches. It reads the controller's builds to know which module a changed
 // directory is. It serves no request subject and holds no timer: every reaction is a message or a watch (ADR 0437 §8).
+//
+// Its build of 2026-10-24 00:37 named a program whose push never reached the artifact store, and a retry sends that
+// same build again; this paragraph was added only to give the indexer a new build (issue 1933).
 package main
 
 import (
@@ -288,7 +291,7 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	}
 	defer calls.Close()
 	ix := &index.Indexer{Store: kvStore{candidates}, Modules: kvStore{modules}, Manifests: kvStore{manifests}, Builds: known, Logf: logger.Printf,
-		Named: namedVia(calls.Call)}
+		Named: namedVia(calls.Call), Trunk: trunkVia(calls.Call), Contains: containsVia(calls.Call)}
 	// The gate's source bucket (mesh-delivery-gate_source) comes with the gate (release 3e, novox/hq ADR 0450 §1): its key
 	// main is the mesh's source revision, which stamps the modules (issue 1344). Where it does not exist yet the indexer does
 	// not wait for it (that needs a timer, ADR 0437 §8): it says so, and is started again with the gate.
@@ -325,6 +328,10 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 	if err := ix.RecomputeAtStart(ctx); err != nil {
 		logger.Printf("computing the new-form fingerprints at start: %v", err)
 	}
+	// The modules the trunk no longer holds go from the bucket (issue 1900); a merge does the same from its own message.
+	if err := ix.Reconcile(ctx); err != nil {
+		logger.Printf("dropping the modules the trunk does not hold at start: %v", err)
+	}
 	// A build module says each time it wrote its toolchains key: its stream, and the indexer's durable consumer on it, are
 	// made by the controller as the forge's are. Where the stream is not there yet the indexer says so and is started again
 	// with the build module, as with the gate's source.

modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named.go

@@ -46,3 +46,50 @@ func namedVia(call toolCaller) func(ctx context.Context, repository, sha string,
 		return a.Paths, nil
 	}
 }
+
+// trunkVia asks the forge for the module directories of a commit (issue 1900): the keys of the `trees` the same tool
+// answers without paths, one per directory that holds a module.json (the root as ""; the tool lists no other).
+func trunkVia(call toolCaller) func(ctx context.Context, repository, sha string) ([]string, error) {
+	return func(_ context.Context, repository, sha string) ([]string, error) {
+		owner, repo, ok := strings.Cut(delivery.RepositoryName(repository), "/")
+		if !ok {
+			return nil, fmt.Errorf("%q is not <owner>/<name>", repository)
+		}
+		raw, err := call(commitTreesTool, map[string]any{"owner": owner, "repo": repo, "sha": sha})
+		if err != nil {
+			return nil, err
+		}
+		var a struct {
+			Trees map[string]string `json:"trees"`
+		}
+		if err := json.Unmarshal(raw, &a); err != nil {
+			return nil, fmt.Errorf("the answer of %s is not {root, trees}: %w", commitTreesTool, err)
+		}
+		dirs := make([]string, 0, len(a.Trees))
+		for dir := range a.Trees {
+			dirs = append(dirs, dir)
+		}
+		return dirs, nil
+	}
+}
+
+// containsVia asks the forge whether a commit is in another (gitea.gitea_contains: contains is true for the same commit or an ancestor).
+func containsVia(call toolCaller) func(ctx context.Context, repository, commit, in string) (bool, error) {
+	return func(_ context.Context, repository, commit, in string) (bool, error) {
+		owner, repo, ok := strings.Cut(delivery.RepositoryName(repository), "/")
+		if !ok {
+			return false, fmt.Errorf("%q is not <owner>/<name>", repository)
+		}
+		raw, err := call("gitea.gitea_contains", map[string]any{"owner": owner, "repo": repo, "commit": commit, "in": in})
+		if err != nil {
+			return false, err
+		}
+		var a struct {
+			Contains *bool `json:"contains"`
+		}
+		if err := json.Unmarshal(raw, &a); err != nil || a.Contains == nil {
+			return false, fmt.Errorf("the answer of gitea.gitea_contains names no contains: %v", err)
+		}
+		return *a.Contains, nil
+	}
+}

modules/mesh-delivery-indexer/cmd/mesh-delivery-indexer/named_test.go

@@ -3,6 +3,8 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"slices"
+	"strings"
 	"testing"
 )
 
@@ -29,3 +31,22 @@ func TestNamedViaAsksTheTreesToolWithThePathsAndTakesTheirObjects(t *testing.T)
 		t.Error("an answer missing a path asked was taken")
 	}
 }
+
+func TestTheTrunkIsTheDirectoriesTheForgeListsTrees(t *testing.T) { // 1900/AC3
+	var gotArgs any
+	call := func(key string, body any) (json.RawMessage, error) {
+		gotArgs = body
+		return json.RawMessage(`{"root":"r","trees":{"modules/a":"x","modules/b":"y"}}`), nil
+	}
+	dirs, err := trunkVia(call)(context.Background(), "novox/mesh-catalog", strings.Repeat("a", 40))
+	if err != nil {
+		t.Fatal(err)
+	}
+	slices.Sort(dirs)
+	if !slices.Equal(dirs, []string{"modules/a", "modules/b"}) {
+		t.Errorf("dirs = %v", dirs)
+	}
+	if _, has := gotArgs.(map[string]any)["paths"]; has {
+		t.Error("the trunk asked for paths")
+	}
+}

modules/mesh-delivery-indexer/internal/index/candidates.go

@@ -52,7 +52,10 @@ type Indexer struct {
 	// manifest's paths (ADR 0495 clause 1, the lead's decision L8 of R4e). Nil asks nothing, and a module naming paths
 	// has none.
 	Named func(ctx context.Context, repository, sha string, paths map[string][]string) (map[string]map[string]string, error)
-	Logf  func(format string, args ...any)
+	Trunk func(ctx context.Context, repository, sha string) ([]string, error)
+	// Contains says whether a commit is the second or an ancestor of it (gitea.gitea_contains).
+	Contains func(ctx context.Context, repository, commit, in string) (bool, error)
+	Logf     func(format string, args ...any)
 
 	mu         sync.Mutex // guards source, toolchains and previews, which the watches and the forge messages all reach
 	source     sourceNow

modules/mesh-delivery-indexer/internal/index/inputs.go

@@ -69,7 +69,7 @@ func inputsOf(module, raw, tree string, locks map[string]string, base baseFP) mo
 func inputsOfNamed(module, raw, tree string, locks, objects map[string]string, base baseFP) moduleInputs {
 	m, err := catalogue.ParseManifestForInputs([]byte(raw))
 	if err != nil {
-		return moduleInputs{None2: "the manifest cannot be read: " + err.Error()}
+		return moduleInputs{None2: None2Unreadable + err.Error()}
 	}
 	if m.Module != module {
 		return moduleInputs{None2: fmt.Sprintf("the manifest is of module %q, not %q", m.Module, module)}

modules/mesh-delivery-indexer/internal/index/inputs_test.go

@@ -111,7 +111,8 @@ func TestABaseEntersByTheFingerprintOfItsModuleOrNamesItsAbsence(t *testing.T) {
 	}
 	// Through the indexer: modules.mesh-tools holds a fingerprint of the new form (a record written by a later release).
 	ix, mods, _ := manifestsIndexer(t, rec(t, "build-1", "avahi", catalogueRepo, "modules/avahi", "main", "", "2026-10-19T09:00:00Z", aInputs))
-	mods.put("mesh-tools", mustEncode(t, delivery.Module{Repository: catalogueRepo, Commit: merge, None: "x", FP2: fp, Manifest: strings.Repeat("a", 64)}))
+	mods.put("mesh-tools", mustEncode(t, delivery.Module{Repository: "novox/mesh-tools", // a base held of another repository stays when the catalogue merges (issue 1900)
+		Commit: merge, None: "x", FP2: fp, Manifest: strings.Repeat("a", 64)}))
 	f := withManifests(mergedMsg(catalogueRepo, map[string]string{"modules/avahi": "t"}), map[string]string{"modules/avahi": aModuleWithABase(t)}, nil)
 	if err := ix.Apply(context.Background(), f); err != nil {
 		t.Fatal(err)

modules/mesh-delivery-indexer/internal/index/modules.go

@@ -2,8 +2,10 @@ package index
 
 import (
 	"context"
+	"fmt"
 	"maps"
 	"slices"
+	"strings"
 
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
@@ -33,18 +35,22 @@ func (ix *Indexer) applyMerged(ctx context.Context, f delivery.Forge) error {
 	objects, namedErr := ix.namedObjects(ctx, f)
 	overlay := map[string]delivery.Module{}
 	dirOf := map[string]string{}
+	named, every := map[string]bool{}, true // every module the message's manifests name, and whether each names one
 	for _, dir := range slices.Sorted(maps.Keys(f.Manifests)) {
 		raw := f.Manifests[dir]
 		name := manifestModule(raw)
 		if name == "" {
 			ix.logf("%s at %s: the manifest in %q names no module, so no module is written for it", f.Repository, f.Merge, dir)
+			every = false
 			continue
 		}
 		key, err := delivery.ModulesKey(name)
 		if err != nil {
+			every = false
 			ix.logf("%s: the module %q has no usable key, skipped: %v", f.Repository, name, err)
 			continue
 		}
+		named[key] = true
 		cur, has := held[key]
 		if has && cur.Repository != "" && !delivery.SameRepository(cur.Repository, f.Repository) {
 			ix.logf("%s at %s: %q names the module %s, which the indexer holds of %s; left as it is (a move between repositories is the operator's)", f.Repository, f.Merge, dir, name, cur.Repository)
@@ -64,12 +70,24 @@ func (ix *Indexer) applyMerged(ctx context.Context, f delivery.Forge) error {
 		} else {
 			in := inputsOfNamed(name, raw, f.Trees[dir], f.Locks[dir], objects[dir], ix.baseFP(ctx))
 			next.Inputs2, next.None2, next.ArtifactPaths = in.Kept, in.None2, in.ArtifactPaths
+			if in.Kept == nil && strings.HasPrefix(in.None2, None2Unreadable) {
+				// The manifest cannot be read by this SDK; the inputs the merge carried are kept all the same, so a later SDK
+				// that reads it judges the module again at start with no merge (issue 1923).
+				next.Inputs2 = unreadInputs(f.Trees[dir], f.Locks[dir], f.Paths[dir])
+			}
 			if in.Kept == nil && namedErr[dir] != "" {
 				next.None2 = in.None2 + ": the forge could not say them: " + namedErr[dir]
 			}
 		}
 		overlay[key] = next
 	}
+	// A module of this repository the merge commit holds no module.json for is gone from the trunk, and so is its key
+	// (issue 1900). A message that carries no manifests (an older writer) or one that cannot be read whole says nothing.
+	if len(f.Manifests) > 0 && every {
+		if err := ix.dropRemoved(ctx, f.Repository, held, func(key string, _ delivery.Module) bool { return named[key] }); err != nil {
+			return err
+		}
+	}
 	// What this merge moved reaches the modules standing on it (a base's tree, build-agent's fingerprint), in the graph's order.
 	return ix.recomputeWith(ctx, overlay)
 }
@@ -149,3 +167,115 @@ func (ix *Indexer) namedObjects(ctx context.Context, f delivery.Forge) (map[stri
 	}
 	return objects, nil
 }
+
+// dropRemoved deletes, from the modules the bucket holds of the repository, each one the trunk no longer holds (issue 1900):
+// held(key, module) says whether the trunk holds it. A module of another repository, or of none known, is never touched.
+func (ix *Indexer) dropRemoved(ctx context.Context, repository string, held map[string]delivery.Module, trunkHolds func(key string, m delivery.Module) bool) error {
+	for _, key := range slices.Sorted(maps.Keys(held)) {
+		cur := held[key]
+		if cur.Repository == "" || !delivery.SameRepository(cur.Repository, repository) || trunkHolds(key, cur) {
+			continue
+		}
+		err := write(ctx, ix.Modules, key, func(value []byte, found bool) ([]byte, bool, error) {
+			if !found {
+				return nil, false, nil
+			}
+			if m, err := delivery.DecodeModule(value); err != nil || !delivery.SameRepository(m.Repository, repository) {
+				return nil, false, nil
+			}
+			return nil, true, nil
+		})
+		if err != nil {
+			return fmt.Errorf("modules.%s: %w", key, err)
+		}
+		ix.logf("modules.%s deleted: %s holds no module of that name at its trunk (issue 1900)", key, repository)
+	}
+	return nil
+}
+
+// Reconcile deletes the modules keys whose module the trunk does not hold, for each repository the latest source names a
+// head of: the module directories at that head are asked of the forge (Trunk), and a module of the repository whose
+// directory is not among them goes (issue 1900). It is run at the indexer's start; a merge does the same from its own
+// message (applyMerged). A repository whose trunk cannot be read, or reads as holding no module at all, is left as it is
+// and said: a failure never empties the bucket.
+func (ix *Indexer) Reconcile(ctx context.Context) error {
+	if ix.Modules == nil || ix.Trunk == nil {
+		return nil
+	}
+	ix.mu.Lock()
+	heads := maps.Clone(ix.source.heads)
+	ix.mu.Unlock()
+	held, err := ix.heldModules(ctx)
+	if err != nil {
+		return err
+	}
+	for _, repository := range slices.Sorted(maps.Keys(heads)) {
+		mine := map[string]delivery.Module{}
+		for key, m := range held {
+			if m.Repository != "" && delivery.SameRepository(m.Repository, repository) {
+				mine[key] = m
+			}
+		}
+		if len(mine) == 0 {
+			continue
+		}
+		dirs, err := ix.Trunk(ctx, repository, heads[repository])
+		if err != nil {
+			ix.logf("%s at %s: the modules of the trunk cannot be read, so none is dropped: %v", repository, heads[repository], err)
+			continue
+		}
+		if len(dirs) == 0 {
+			ix.logf("%s at %s: the trunk reads as holding no module, so none is dropped", repository, heads[repository])
+			continue
+		}
+		there := map[string]bool{}
+		for _, d := range dirs {
+			there[pathOf(strings.Trim(d, "/"))] = true
+		}
+		head := heads[repository]
+		// The source can lag a merge already applied: a key written at a commit the head read does not hold (a merge heard
+		// first) is not read as removed, only one whose commit the head is, or contains.
+		stays := func(_ string, m delivery.Module) bool {
+			if m.Path == "" || there[m.Path] {
+				return true
+			}
+			if m.Commit == head {
+				return false
+			}
+			if m.Commit == "" || ix.Contains == nil {
+				return true
+			}
+			in, err := ix.Contains(ctx, repository, m.Commit, head)
+			if err != nil {
+				ix.logf("%s: whether %s is in %s cannot be read, so the module at %s is kept: %v", repository, m.Commit, head, m.Path, err)
+				return true
+			}
+			return !in
+		}
+		if err := ix.dropRemoved(ctx, repository, mine, stays); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// None2Unreadable begins the reason of a module whose manifest the running SDK cannot read.
+const None2Unreadable = "the manifest cannot be read: "
+
+// unreadInputs are the inputs a merge carried for a module whose manifest cannot be read: the directory's tree, the lock
+// hashes by file name (the artifacts that own them are not known without the manifest) and the objects of the named
+// paths the message carried; nil when the message carried no tree. Judging the manifest again (rejudged) turns them into
+// the inputs of the module (issue 1923).
+func unreadInputs(tree string, locks, paths map[string]string) *delivery.KeptInputs2 {
+	if tree == "" {
+		return nil
+	}
+	in := &delivery.KeptInputs2{Tree: tree}
+	if len(locks) > 0 {
+		in.Locks = maps.Clone(locks)
+	}
+	if len(paths) > 0 {
+		in.Paths = maps.Clone(paths)
+	}
+	return in
+}

modules/mesh-delivery-indexer/internal/index/remove_test.go

@@ -0,0 +1,144 @@
+package index
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+func twoModules(t *testing.T) (*Indexer, *memStore) {
+	t.Helper()
+	ix, mods := modulesIndexer(t)
+	if err := ix.Apply(context.Background(), mergedMsg(catalogueRepo, map[string]string{"modules/a": "t", "modules/b": "t"})); err != nil {
+		t.Fatal(err)
+	}
+	for _, k := range []string{"a", "b"} {
+		if _, ok := mods.vals[k]; !ok {
+			t.Fatalf("setup: modules.%s not written", k)
+		}
+	}
+	return ix, mods
+}
+
+func TestAMergeThatRemovesAModuleDeletesItsKey(t *testing.T) { // 1900/AC1
+	ix, mods := twoModules(t)
+	if err := ix.Apply(context.Background(), mergedMsg(catalogueRepo, map[string]string{"modules/a": "t2"})); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := mods.vals["b"]; ok {
+		t.Error("modules.b is still held after a merge whose trunk has no module b")
+	}
+	if _, ok := mods.vals["a"]; !ok {
+		t.Error("modules.a, which the trunk still holds, was deleted")
+	}
+}
+
+func TestAMergeLeavesTheModulesOfAnotherRepository(t *testing.T) { // 1900/AC1 (scope)
+	ix, mods := twoModules(t)
+	if err := ix.Apply(context.Background(), mergedMsg("novox/mesh-delivery", map[string]string{"modules/c": "t"})); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := mods.vals["a"]; !ok {
+		t.Error("a merge of another repository deleted modules.a")
+	}
+	if _, ok := mods.vals["b"]; !ok {
+		t.Error("a merge of another repository deleted modules.b")
+	}
+}
+
+func TestAMergeWithoutManifestsDeletesNothing(t *testing.T) { // 1900/AC1: older writers send none, which does not say the trunk is empty
+	ix, mods := twoModules(t)
+	f := mergedMsg(catalogueRepo, map[string]string{"modules/a": "t2"})
+	f.Manifests = nil
+	if err := ix.Apply(context.Background(), f); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := mods.vals["b"]; !ok {
+		t.Error("a merge message with no manifests deleted modules.b")
+	}
+}
+
+func TestAPathWithoutAModuleJSONIsNeverAModule(t *testing.T) { // 1900/AC2: testdata such as fixture-build
+	ix, mods := twoModules(t)
+	f := mergedMsg(catalogueRepo, map[string]string{"modules/a": "t2"})
+	f.Trees["testdata/fixture-build"] = "t" // a directory in the tree whose module.json the message does not carry
+	if err := ix.Apply(context.Background(), f); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := mods.vals["fixture-build"]; ok {
+		t.Error("modules.fixture-build written for a path without a module.json")
+	}
+}
+
+func TestStartingDeletesTheKeysTheTrunkDoesNotHold(t *testing.T) { // 1900/AC3
+	ix, mods := twoModules(t)
+	ctx := context.Background()
+	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
+		t.Fatal(err)
+	}
+	var asked string
+	ix.Trunk = func(_ context.Context, repository, sha string) ([]string, error) {
+		asked = repository + "@" + sha
+		return []string{"modules/a"}, nil
+	}
+	ix.Contains = func(context.Context, string, string, string) (bool, error) { return true, nil }
+	if err := ix.Reconcile(ctx); err != nil {
+		t.Fatal(err)
+	}
+	if asked != catalogueRepo+"@"+merge {
+		t.Errorf("the trunk was asked as %q, want the source's head of the repository", asked)
+	}
+	if _, ok := mods.vals["b"]; ok {
+		t.Error("modules.b is still held though the trunk holds no module at modules/b")
+	}
+	if _, ok := mods.vals["a"]; !ok {
+		t.Error("modules.a was deleted")
+	}
+}
+
+func TestStartingDeletesNothingWhenTheTrunkCannotBeRead(t *testing.T) { // 1900/AC3: failure is loud, never a mass delete
+	ix, mods := twoModules(t)
+	ctx := context.Background()
+	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, merge)); err != nil {
+		t.Fatal(err)
+	}
+	for name, trunk := range map[string]func(context.Context, string, string) ([]string, error){
+		"an error":         func(context.Context, string, string) ([]string, error) { return nil, errors.New("forge down") },
+		"no module at all": func(context.Context, string, string) ([]string, error) { return nil, nil },
+	} {
+		ix.Trunk = trunk
+		_ = ix.Reconcile(ctx)
+		if len(mods.vals) != 2 {
+			t.Errorf("%s: %d keys held, want 2 untouched", name, len(mods.vals))
+		}
+	}
+	_ = delivery.RootPath
+}
+
+func TestAKeyWrittenAheadOfTheSourceHeadStaysAndOneWithoutAPathIsSkipped(t *testing.T) { // 1900/AC3 (review): the source lags a merge already applied
+	ix, mods := twoModules(t) // written at the merge commit C
+	ctx := context.Background()
+	const older = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+	if err := ix.ApplySource(ctx, 3, sourceOf(catalogueRepo, older)); err != nil {
+		t.Fatal(err)
+	}
+	mods.put("nopath", mustEncode(t, delivery.Module{Repository: catalogueRepo, Commit: older, None2: "x", Manifest: strings.Repeat("a", 64)}))
+	ix.Trunk = func(context.Context, string, string) ([]string, error) { return []string{"modules/a"}, nil }
+	ix.Contains = func(_ context.Context, _, commit, in string) (bool, error) { return commit == in, nil } // C is not in B
+	if err := ix.Reconcile(ctx); err != nil {
+		t.Fatal(err)
+	}
+	for _, k := range []string{"a", "b", "nopath"} {
+		if _, ok := mods.vals[k]; !ok {
+			t.Errorf("modules.%s was deleted", k)
+		}
+	}
+	ix.Contains = func(context.Context, string, string, string) (bool, error) { return false, errors.New("forge down") }
+	_ = ix.Reconcile(ctx)
+	if _, ok := mods.vals["b"]; !ok {
+		t.Error("modules.b deleted though whether its commit is in the head cannot be read")
+	}
+}

modules/mesh-delivery-indexer/internal/index/stale_none2_test.go

@@ -0,0 +1,77 @@
+package index
+
+import (
+	"context"
+	"strings"
+	"testing"
+)
+
+// unreadableAvahi is avahi's manifest with a field the running parser refuses: the shape of a manifest an older SDK could
+// not read.
+func unreadableAvahi(t *testing.T) string {
+	t.Helper()
+	raw := strings.Replace(catalogueManifest(t, "avahi"), `"version": "1",`, `"version": "1", "scope": "everything",`, 1)
+	if raw == catalogueManifest(t, "avahi") {
+		t.Fatal("the fixture has no version line")
+	}
+	return raw
+}
+
+func TestAMergeOfAnUnreadableManifestKeepsTheInputsBesideTheReason(t *testing.T) { // 1923/AC1
+	_, mods := newFormIndexer(t, mod{"avahi", unreadableAvahi(t)})
+	m, ok := moduleOf(t, mods, "avahi")
+	if !ok || !strings.HasPrefix(m.None2, "the manifest cannot be read: ") || m.FP2 != "" {
+		t.Fatalf("module = %+v, want the reason 'the manifest cannot be read' and no fingerprint", m)
+	}
+	if m.Inputs2 == nil || m.Inputs2.Tree != "tree-avahi" || m.Inputs2.Locks["go.sum"] != avahiGoSum {
+		t.Errorf("inputs = %+v, want the directory's tree and its lock hashes kept", m.Inputs2)
+	}
+}
+
+func TestAStaleUnreadableVerdictIsJudgedAgainAtStartAndAnotherReasonIsLeft(t *testing.T) { // 1923/AC2
+	ctx := context.Background()
+	// The fingerprint a merge of the readable manifest gives.
+	ixGood, good := newFormIndexer(t, mod{"avahi", catalogueManifest(t, "avahi")})
+	reportToolchain(t, ixGood, "mesh-build-go", "novox", "go", "go1.27.1")
+	reportToolchain(t, ixGood, "mesh-build-go", "ace", "go", "go1.27.1")
+	want, _ := moduleOf(t, good, "avahi")
+	if want.FP2 == "" {
+		t.Fatalf("the readable manifest gives no fingerprint: %+v", want)
+	}
+
+	// The same module as an older SDK wrote it: the reason, the inputs kept at the merge, the manifest stored by digest.
+	ix, mods := newFormIndexer(t, mod{"avahi", unreadableAvahi(t)})
+	reportToolchain(t, ix, "mesh-build-go", "novox", "go", "go1.27.1")
+	reportToolchain(t, ix, "mesh-build-go", "ace", "go", "go1.27.1")
+	stale, _ := moduleOf(t, mods, "avahi")
+	stale.Manifest = want.Manifest
+	ix.Manifests.(*memStore).put(want.Manifest, good2(t, ixGood, want.Manifest))
+	mods.put("avahi", mustEncode(t, stale))
+	if err := ix.Recompute(ctx); err != nil {
+		t.Fatal(err)
+	}
+	got, _ := moduleOf(t, mods, "avahi")
+	if got.FP2 != want.FP2 || got.None2 != "" {
+		t.Errorf("after the start: fp2 %q none2 %q, want %q and no reason", got.FP2, got.None2, want.FP2)
+	}
+
+	// A manifest still unreadable keeps its value as it was.
+	ix2, mods2 := newFormIndexer(t, mod{"avahi", unreadableAvahi(t)})
+	before := string(mods2.vals["avahi"])
+	if err := ix2.Recompute(ctx); err != nil {
+		t.Fatal(err)
+	}
+	if after := string(mods2.vals["avahi"]); after != before {
+		t.Errorf("a manifest still unreadable changed the value:\n%s\n%s", before, after)
+	}
+}
+
+// good2 is the stored manifest value of the digest in the indexer that merged the readable manifest.
+func good2(t *testing.T, ix *Indexer, digest string) []byte {
+	t.Helper()
+	v, _, found, err := ix.Manifests.Get(context.Background(), digest)
+	if err != nil || !found {
+		t.Fatalf("manifests.%s: %v %v", digest, found, err)
+	}
+	return v
+}

modules/mesh-delivery-indexer/internal/index/toolchains.go

@@ -156,6 +156,7 @@ func (ix *Indexer) recomputeModules(ctx context.Context, overlay map[string]deli
 	}
 	slices.Sort(keys)
 	held := map[string]delivery.Module{}
+	stale := map[string]bool{} // values an SDK that could not read their manifest wrote, judged again (issue 1923)
 	all := map[string]*known{}
 	for _, key := range keys {
 		cur, ok := overlay[key]
@@ -176,11 +177,15 @@ func (ix *Indexer) recomputeModules(ctx context.Context, overlay map[string]deli
 		if cur.Manifest == "" || cur.Inputs2 == nil {
 			continue
 		}
-		m, err := ix.manifestOf(ctx, cur.Manifest)
+		raw, m, err := ix.manifestRaw(ctx, cur.Manifest)
 		if err != nil {
 			ix.logf("modules.%s: its manifest %s cannot be read, left: %v", key, cur.Manifest, err)
 			continue
 		}
+		if again, ok := ix.rejudged(ctx, m, cur, raw); ok {
+			cur, stale[key] = again, true
+			held[key] = cur
+		}
 		all[key] = &known{key: key, cur: cur, languages: languagesOf(m), bases: basesOf(m), contexts: hasContext(m)}
 	}
 	tools := ix.agreed()
@@ -275,10 +280,10 @@ func (ix *Indexer) recomputeModules(ctx context.Context, overlay map[string]deli
 			finals[key] = final
 			continue
 		}
-		if k.cur.FP2 == r.fp && k.cur.None2 == r.none && reflect.DeepEqual(k.cur.Toolchains, r.tcs) {
+		if !stale[key] && k.cur.FP2 == r.fp && k.cur.None2 == r.none && reflect.DeepEqual(k.cur.Toolchains, r.tcs) {
 			continue
 		}
-		digest, inputs := k.cur.Manifest, k.cur.Inputs2
+		digest, inputs, paths := k.cur.Manifest, k.cur.Inputs2, k.cur.ArtifactPaths
 		err := write(ctx, ix.Modules, key, func(value []byte, found bool) ([]byte, bool, error) {
 			if !found {
 				return nil, false, nil
@@ -291,7 +296,7 @@ func (ix *Indexer) recomputeModules(ctx context.Context, overlay map[string]deli
 				return nil, false, nil
 			}
 			cur.FP2, cur.None2, cur.Toolchains = r.fp, r.none, r.tcs
-			cur.Inputs2 = inputs
+			cur.Inputs2, cur.ArtifactPaths = inputs, paths
 			data, err := delivery.EncodeModule(cur)
 			return data, false, err
 		})
@@ -326,24 +331,41 @@ func (ix *Indexer) writeOverlay(ctx context.Context, overlay, finals map[string]
 	return nil
 }
 
-// manifestOf is the parsed manifest manifests.<digest> holds.
-func (ix *Indexer) manifestOf(ctx context.Context, digest string) (catalogue.Manifest, error) {
+// manifestRaw is manifests.<digest>: the manifest as stored and parsed by the running SDK.
+func (ix *Indexer) manifestRaw(ctx context.Context, digest string) (string, catalogue.Manifest, error) {
 	key, err := delivery.ManifestsKey(digest)
 	if err != nil {
-		return catalogue.Manifest{}, err
+		return "", catalogue.Manifest{}, err
 	}
 	value, _, found, err := ix.Manifests.Get(ctx, key)
 	if err != nil {
-		return catalogue.Manifest{}, err
+		return "", catalogue.Manifest{}, err
 	}
 	if !found {
-		return catalogue.Manifest{}, fmt.Errorf("manifests.%s is not there", key)
+		return "", catalogue.Manifest{}, fmt.Errorf("manifests.%s is not there", key)
 	}
 	kept, err := delivery.DecodeManifest(value)
 	if err != nil {
-		return catalogue.Manifest{}, err
+		return "", catalogue.Manifest{}, err
 	}
-	return catalogue.ParseManifestForInputs([]byte(kept.JSON))
+	m, err := catalogue.ParseManifestForInputs([]byte(kept.JSON))
+	return kept.JSON, m, err
+}
+
+// rejudged is a value an SDK that could not read its manifest wrote, as the running SDK judges it: its kept inputs (the
+// tree, the lock hashes by file name, the named paths' objects) taken through the manifest as a merge takes them, and the
+// reason that gives. It answers false for any other value, and for one whose manifest the running SDK still cannot make
+// inputs of (issue 1923).
+func (ix *Indexer) rejudged(ctx context.Context, m catalogue.Manifest, cur delivery.Module, raw string) (delivery.Module, bool) {
+	if cur.FP2 != "" || cur.Inputs2 == nil || !strings.HasPrefix(cur.None2, None2Unreadable) {
+		return cur, false
+	}
+	in := inputsOfNamed(m.Module, raw, cur.Inputs2.Tree, cur.Inputs2.Locks, cur.Inputs2.Paths, ix.baseFP(ctx))
+	if in.Kept == nil {
+		return cur, false
+	}
+	cur.Inputs2, cur.None2, cur.ArtifactPaths = in.Kept, in.None2, in.ArtifactPaths
+	return cur, true
 }
 
 // hasContext is whether an artifact of the manifest reads another repository's tree.

modules/mesh-delivery-indexer/manifest_test.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"regexp"
 	"slices"
 	"strings"
 	"testing"
@@ -94,9 +95,10 @@ func TestManifestDeclarations(t *testing.T) { // 1238/AC1, 1444 (reads the build
 	if m.SecretsOwner != "mesh-delivery-indexer" {
 		t.Errorf("secrets-owner = %q", m.SecretsOwner)
 	}
-	// One invoke: the forge's trees with the named paths' objects, since the indexer is the one reader of a manifest's paths
-	// (ADR 0499 clauses 2 and 3, ADR 0495 clause 1, the lead's decision L8 of R4e).
-	if want := []string{"gitea.gitea_commit_trees"}; !reflect.DeepEqual(m.Invokes, want) {
+	// Two invokes: the forge's trees (the named paths' objects, since the indexer is the one reader of a manifest's paths:
+	// ADR 0499 clauses 2 and 3, ADR 0495 clause 1; and the module directories of the trunk, issue 1900) and whether a
+	// commit is in another (issue 1900).
+	if want := []string{"gitea.gitea_commit_trees", "gitea.gitea_contains"}; !reflect.DeepEqual(m.Invokes, want) {
 		t.Errorf("invokes = %v, want %v", m.Invokes, want)
 	}
 	// No emits, no streams, no bus, no seat, no tool (ADR 0437 §4).
@@ -169,3 +171,32 @@ func TestServesNoRequestSubjectAndHoldsNoTicker(t *testing.T) { // 1238/AC9 (ADR
 		t.Fatalf("read %d source files, want the program's", files)
 	}
 }
+
+// Every forge tool the program calls is granted in invokes, or the bus refuses the call (issue 1900).
+func TestEveryGiteaToolTheCodeCallsIsInInvokes(t *testing.T) {
+	m, _ := load(t)
+	files, err := filepath.Glob("cmd/mesh-delivery-indexer/*.go")
+	if err != nil || len(files) == 0 {
+		t.Fatalf("no program files: %v", err)
+	}
+	re := regexp.MustCompile(`gitea\.gitea_[a-z_]+`)
+	seen := 0
+	for _, f := range files {
+		if strings.HasSuffix(f, "_test.go") {
+			continue
+		}
+		src, err := os.ReadFile(f)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, tool := range re.FindAllString(string(src), -1) {
+			seen++
+			if !slices.Contains(m.Invokes, tool) {
+				t.Errorf("%s calls %s, which invokes does not grant", f, tool)
+			}
+		}
+	}
+	if seen < 2 {
+		t.Errorf("found %d tool names in the program, want at least the two it calls", seen)
+	}
+}

modules/mesh-delivery-indexer/module.json

@@ -21,7 +21,8 @@
     "mesh-delivery-gate.source"
   ],
   "invokes": [
-    "gitea.gitea_commit_trees"
+    "gitea.gitea_commit_trees",
+    "gitea.gitea_contains"
   ],
   "own-secrets": {
     "broker": "${dir:state}/broker"