Count the work the take-ins start in the background, so a test's mesh closes only once that work has ended (issue 1851, A5-A7; issue 1790, D3)

cmd/mesh-controller/first_builds.go

@@ -94,7 +94,7 @@ func askFirstBuilds(ctx context.Context, open *stores, m link.SourceMoved, now t
 		fmt.Printf("  the indexer's modules of %s cannot be read now (%v): they are registered when the builder's next "+
 			"write of one wakes the take-in\n", repository, err)
 	case len(modules) > 0:
-		go takeNewModules(context.WithoutCancel(ctx), open, modules...)
+		inBackground(func() { takeNewModules(context.WithoutCancel(ctx), open, modules...) })
 	}
 	return nil
 }

cmd/mesh-controller/mesh_for_test.go

@@ -56,6 +56,8 @@ func aMeshOnTheStore(t *testing.T) *stores {
 		t.Fatal(err)
 	}
 	t.Cleanup(open.Close)
+	// The work this mesh started in the background ends before its stores close (cleanups run last first).
+	t.Cleanup(background.Wait)
 	// A condition store of its own, held in memory (novox/hq to-be 45 §2): status leads with what is
 	// open, and a mesh with no bus would otherwise read as one whose conditions cannot be read.
 	withConditionsInMemory(t)

cmd/mesh-controller/new_modules.go

@@ -200,10 +200,10 @@ func newModuleObservations(now time.Time) []conditions.Observation {
 // watchNewModules wakes the take-in of new modules for each module the builder or the indexer writes, until ctx ends, and
 // looks at every module once now. A bucket not there yet is said: the look at start and a first merge's word still work.
 func watchNewModules(ctx context.Context, open *stores) {
-	go func() {
+	inBackground(func() {
 		answerHeldMerges(ctx, open.inventory)
 		takeNewModules(ctx, open)
-	}()
+	})
 	keys, closeKeys, err := openBuilderKeys()
 	if err != nil {
 		fmt.Printf("new modules: the builder's keys are not watched: %v\n", err)
@@ -223,7 +223,7 @@ func watchNewModules(ctx context.Context, open *stores) {
 // wakeNewModule takes module in when the catalogue does not hold it: never on the watch's own goroutine, which must keep
 // draining.
 func wakeNewModule(ctx context.Context, open *stores, module string) {
-	go func() {
+	inBackground(func() {
 		entries, err := open.inventory.Catalogued(ctx)
 		if err != nil {
 			return
@@ -236,6 +236,19 @@ func wakeNewModule(ctx context.Context, open *stores, module string) {
 			}
 		}
 		takeNewModules(ctx, open, module)
+	})
+}
+
+// background is the work the take-ins of keys and of announcements start beside the event that woke them, so a test
+// ends only once the work its mesh started has.
+var background sync.WaitGroup
+
+// inBackground runs work beside the caller, counted in background.
+func inBackground(work func()) {
+	background.Add(1)
+	go func() {
+		defer background.Done()
+		work()
 	}()
 }
 

cmd/mesh-controller/plan_keys.go

@@ -73,7 +73,7 @@ var keyTakes = struct {
 // the buckets and the records; a done key not recorded yet is taken in off the plans' hold, and its end asks the look.
 func settleFromKeys(ctx context.Context, open *stores, keys planKeyReads, p *inventory.Plan, tier []string) (bool, error) {
 	return settleKeys(ctx, open.inventory, keys, p, tier, func(module string, trunk sdkdelivery.Module, id string) {
-		go takeKeyOffTheHold(context.WithoutCancel(ctx), open, module, trunk, id)
+		inBackground(func() { takeKeyOffTheHold(context.WithoutCancel(ctx), open, module, trunk, id) })
 	})
 }
 

cmd/mesh-controller/states_announced.go

@@ -67,7 +67,7 @@ func keepAnnouncements(ctx context.Context, js *broker.JetStream, open *stores)
 			return
 		}
 		if changed {
-			go composeAnnouncedReads(context.WithoutCancel(ctx), open)
+			inBackground(func() { composeAnnouncedReads(context.WithoutCancel(ctx), open) })
 		}
 	})
 	if err != nil {