Let delivery-stop leave merges out and walk the others again, so a group stop ends only its own change (hq issue 459, ADR 0299)

One walk carries every merge of its batch, so ending it for one group member
ended every other delivery on it. delivery-stop now takes without: the walk
ends, every other merge it answered is batched again, and each later merge of
a left-out merge's repository is left out too, since it contains it.

cmd/mesh-controller/issue459_test.go

@@ -0,0 +1,177 @@
+package main
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// novox/hq issue 459, ADR 0299: since the merge window one walk carries every merge of its batch, so a stop of one
+// group member through `delivery-stop` ended the walk of every other delivery in it. The stop now names the merges
+// to leave out: the walk is ended, and every other merge it answered is walked again in a fresh batch without them
+// — the stopped merge, and each later merge of its repository's branch, which contains it and ends with it.
+
+// leaved is a kept merge of a repository, made at a moment.
+func leaved(repository, commit string, made time.Time) inventory.BatchedMerge {
+	return inventory.BatchedMerge{Repository: repository, Branch: "main", Commit: commit, Merged: made, Heard: made}
+}
+
+// The stopped merge is left out, and so is each later merge of its repository's branch, naming the merge it
+// contains; an earlier merge of that repository and every other repository's merge are walked again.
+func TestLeftOutAreTheStoppedMergeAndTheMergesThatContainIt(t *testing.T) {
+	c1 := leaved("novox/mesh-catalog", "c1aaaaaaaaaa", t0)
+	c2 := leaved("novox/mesh-catalog", "c2bbbbbbbbbb", t0.Add(10*time.Second))
+	c3 := leaved("novox/mesh-catalog", "c3cccccccccc", t0.Add(20*time.Second))
+	o1 := leaved("novox/one", "o1dddddddddd", t0.Add(5*time.Second))
+	again, out, err := leaveOut([]inventory.BatchedMerge{c1, o1, c2, c3}, []string{"novox/Mesh-Catalog@c2bbbbbbbbbb"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	var walked []string
+	for _, m := range again {
+		walked = append(walked, m.Commit)
+	}
+	if !reflect.DeepEqual(walked, []string{c1.Commit, o1.Commit}) {
+		t.Fatalf("walked again: %v; want the earlier catalogue merge and the other repository's", walked)
+	}
+	want := []inventory.PlanLeftOut{{Repository: "novox/mesh-catalog", Commit: c2.Commit},
+		{Repository: "novox/mesh-catalog", Commit: c3.Commit, Contains: c2.Commit}}
+	if !reflect.DeepEqual(out, want) {
+		t.Fatalf("left out: %+v; want %+v", out, want)
+	}
+	// A merge the walk does not answer is refused, naming it: nothing ends.
+	if _, _, err := leaveOut([]inventory.BatchedMerge{c1, o1}, []string{"novox/mesh-catalog@ffffffffffff"}); err == nil ||
+		!strings.Contains(err.Error(), "ffffffffffff") {
+		t.Fatalf("a merge the walk does not answer was left out: %v", err)
+	}
+	if _, _, err := leaveOut([]inventory.BatchedMerge{c1}, []string{"no-commit"}); err == nil {
+		t.Fatal("a merge without its commit was taken")
+	}
+}
+
+// The seat verb passes the merges to leave out to the command.
+func TestDeliveryStopTakesTheMergesToLeaveOut(t *testing.T) {
+	got, err := argvFor("delivery-stop", map[string]any{"plan": "plan-1", "why": "w", "by": "jochen",
+		"without": "novox/mesh-lab@b1,novox/mesh-lab@b2"})
+	want := []string{"delivery", "stop", "plan-1", "--why", "w", "--by", "mesh-delivery for jochen",
+		"--without", "novox/mesh-lab@b1,novox/mesh-lab@b2"}
+	if err != nil || !reflect.DeepEqual(got, want) {
+		t.Fatalf("delivery-stop with without → %v %v, wanted %v", got, err, want)
+	}
+}
+
+// A walk of the catalogue's merge and another repository's is stopped without the catalogue's: it ends stopped,
+// names the batch that walks the other merge again and the merge it left out, and that batch is cut into a walk
+// that builds the other repository's module alone.
+func TestAStopWithoutAMergeWalksTheOthersAgain(t *testing.T) {
+	open := windowed(t)
+	asksRecorded(t)
+	ctx := t.Context()
+	cat := catalogueMerge("cat1aaaaaaaa", "app", t0)
+	one := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	hear(t, open, cat, t0.Add(time.Second))
+	hear(t, open, one, t0.Add(6*time.Second))
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 || !ws[0].Open() {
+		t.Fatalf("no open walk to stop: %+v", ws)
+	}
+	stopped := ws[0]
+	p, said, err := stopWalkWithout(ctx, open.inventory, stopped.ID, "mesh-delivery for jochen", "its group stopped",
+		[]string{"novox/mesh-catalog@" + cat.Commit}, t0.Add(3*time.Minute))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p.State != inventory.PlanFailed || p.Delivery.Stopped == "" || p.Delivery.WalkedAgainBy == "" ||
+		!reflect.DeepEqual(p.Delivery.LeftOut, []inventory.PlanLeftOut{{Repository: "novox/mesh-catalog", Commit: cat.Commit}}) {
+		t.Fatalf("the stopped walk reads %s %+v", p.State, p.Delivery)
+	}
+	if said.WalkedAgainBy != p.Delivery.WalkedAgainBy || !reflect.DeepEqual(said.WalkedAgain, []string{"novox/one@" + one.Commit}) {
+		t.Fatalf("the stop answered %+v", said)
+	}
+	again, err := open.inventory.MergesOf(ctx, p.Delivery.WalkedAgainBy)
+	if err != nil || len(again) != 1 || again[0].Commit != one.Commit {
+		t.Fatalf("the fresh batch answers %+v (%v); want the other repository's merge alone", again, err)
+	}
+	if left, _ := open.inventory.MergesOf(ctx, stopped.ID); len(left) != 1 || left[0].Commit != cat.Commit {
+		t.Fatalf("the stopped walk still answers %+v; want the left-out merge alone", left)
+	}
+	cutAt(t, open, t0.Add(4*time.Minute))
+	fresh, err := open.inventory.PlanByID(ctx, p.Delivery.WalkedAgainBy)
+	if err != nil || fresh.Batch() || !fresh.Open() {
+		t.Fatalf("the fresh batch was not cut into a walk: %s %v", fresh.State, err)
+	}
+	if _, in := fresh.Modules["one"]; !in {
+		t.Fatalf("the fresh walk does not build one: %v", fresh.Modules)
+	}
+	if _, in := fresh.Modules["app"]; in {
+		t.Fatalf("the fresh walk builds app, whose merge was left out: %v", fresh.Modules)
+	}
+	if len(fresh.Delivery.Merges) != 1 || fresh.Delivery.Merges[0].Commit != one.Commit {
+		t.Fatalf("the fresh walk answers %+v", fresh.Delivery.Merges)
+	}
+	// A stopped walk starts no search of its own (ADR 0276 decision 3 is for a failed one).
+	cutAt(t, open, t0.Add(5*time.Minute))
+	if alone, _ := open.inventory.AloneMerges(ctx); len(alone) != 0 {
+		t.Fatalf("a merge of the stopped walk waits to be walked alone: %+v", alone)
+	}
+}
+
+// A later merge of the stopped merge's repository contains it: it is left out too, named with the merge it
+// contains, and only the other repository's merge is walked again. With nothing left to walk, the walk is only
+// ended. A merge the walk does not answer is refused, and nothing ends.
+func TestAStopWithoutAMergeEndsTheMergesThatContainIt(t *testing.T) {
+	open := windowed(t)
+	asksRecorded(t)
+	ctx := t.Context()
+	first := catalogueMerge("cat1aaaaaaaa", "app", t0)
+	later := catalogueMerge("cat2cccccccc", "notes", t0.Add(10*time.Second))
+	one := repoMerge("one", "one1bbbbbbbb", t0.Add(5*time.Second))
+	hear(t, open, first, t0.Add(time.Second))
+	hear(t, open, one, t0.Add(6*time.Second))
+	hear(t, open, later, t0.Add(11*time.Second))
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	walk := ws[0]
+
+	if _, _, err := stopWalkWithout(ctx, open.inventory, walk.ID, "mesh-delivery for jochen", "x",
+		[]string{"novox/mesh-catalog@ffffffffffff"}, t0.Add(3*time.Minute)); err == nil {
+		t.Fatal("a stop leaving out a merge the walk does not answer was taken")
+	}
+	if p, _ := open.inventory.PlanByID(ctx, walk.ID); !p.Open() {
+		t.Fatalf("a refused stop ended the walk: %s", p.State)
+	}
+
+	p, said, err := stopWalkWithout(ctx, open.inventory, walk.ID, "mesh-delivery for jochen", "its group stopped",
+		[]string{"novox/mesh-catalog@" + first.Commit}, t0.Add(3*time.Minute))
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := []inventory.PlanLeftOut{{Repository: "novox/mesh-catalog", Commit: first.Commit},
+		{Repository: "novox/mesh-catalog", Commit: later.Commit, Contains: first.Commit}}
+	if !reflect.DeepEqual(p.Delivery.LeftOut, want) || !reflect.DeepEqual(said.LeftOut, want) {
+		t.Fatalf("left out %+v, said %+v; want %+v", p.Delivery.LeftOut, said.LeftOut, want)
+	}
+	if !strings.Contains(p.Note, later.Commit[:8]) || !strings.Contains(p.Note, p.Delivery.WalkedAgainBy) {
+		t.Fatalf("the stopped walk's note does not name the merge ended with it and the fresh batch: %q", p.Note)
+	}
+	again, _ := open.inventory.MergesOf(ctx, p.Delivery.WalkedAgainBy)
+	if len(again) != 1 || again[0].Commit != one.Commit {
+		t.Fatalf("walked again: %+v; want the other repository's merge alone", again)
+	}
+
+	// Nothing left once the other repository's merge is left out too: the fresh walk is stopped, and nothing more.
+	cutAt(t, open, t0.Add(4*time.Minute))
+	fresh, _ := open.inventory.PlanByID(ctx, p.Delivery.WalkedAgainBy)
+	q, said, err := stopWalkWithout(ctx, open.inventory, fresh.ID, "mesh-delivery for jochen", "that one too",
+		[]string{"novox/one@" + one.Commit}, t0.Add(5*time.Minute))
+	if err != nil || q.State != inventory.PlanFailed || q.Delivery.WalkedAgainBy != "" || said.WalkedAgainBy != "" {
+		t.Fatalf("a stop leaving nothing to walk: %s %+v %+v %v", q.State, q.Delivery, said, err)
+	}
+	if _, bs := walks(t, open); len(bs) != 0 {
+		t.Fatalf("a batch of nothing was made: %+v", bs)
+	}
+}