mesh-issues and mesh-knowledge: milestones are records of the issue tracker, and progress reads them (ADR 0493 §1 to §4, issue 1781)

mesh-issues keeps each design's milestone in the state milestones (history 5), says milestone-set and
milestone-moved, and serves milestones, milestone-set and milestone-move. An issue's milestone is its own link
of kind milestone, so at most one milestone per issue is checked inside the issue's own write; kind commit
links a fixing commit. The triage links no milestone, pull request or commit. import with milestones=N seeds
a design's table once. mesh-knowledge's progress reads issue-tracker.milestones and its table parse is gone.

Squashed from four commits so the branch history does not carry a compiled bundle that was committed by
mistake (6 MB); the path is now in .gitignore.

modules/mesh-knowledge/cmd/mesh-knowledge/progress_test.go

@@ -45,8 +45,10 @@ type seatsWorld struct {
 	mu     sync.Mutex
 	rows   map[int]json.RawMessage
 	linked map[string][]int
-	asked  map[string]int
-	files  map[string]json.RawMessage
+	// milestones is the tracker's milestone records (issue 1781).
+	milestones json.RawMessage
+	asked      map[string]int
+	files      map[string]json.RawMessage
 }
 
 func newSeatsWorld(t *testing.T) *seatsWorld {
@@ -61,6 +63,7 @@ func newSeatsWorld(t *testing.T) *seatsWorld {
 		_ = json.Unmarshal(r, &n)
 		s.rows[n.Number] = r
 	}
+	s.milestones = readFixture(t, "tracker-milestones-47.json")
 	for _, f := range []string{"deliveries.json", "groups.json", "show-car-hunter-2.json"} {
 		s.files[f] = readFixture(t, f)
 	}
@@ -86,9 +89,15 @@ func (s *seatsWorld) ask(key string, body any) (json.RawMessage, error) {
 		Linked  string `json:"linked"`
 		Number  int    `json:"number"`
 		ID      string `json:"id"`
+		Design  int    `json:"design"`
 	}
 	_ = json.Unmarshal(raw, &a)
 	switch key {
+	case MilestonesVerb:
+		if a.Design != 0 && a.Design != 47 {
+			return json.RawMessage(`{"milestones": []}`), nil
+		}
+		return s.milestones, nil
 	case "seat:issue-tracker.list":
 		numbers := a.Numbers
 		if a.Linked != "" {
@@ -131,31 +140,37 @@ func (c *countingRecords) Read(p string) (string, string, error) {
 	return content, c.commit, err
 }
 
-// 1947/AC2: the milestone table of design 47, as hq holds it, read into milestones with their issues, and what the
-// prose does not say for certain said as warnings.
-func TestTheDesignReaderReadsTheMilestoneTable(t *testing.T) {
+// 1947/AC2, as issue 1781 changed it: a design's title, state and decisions are hq's; its milestones are the issue
+// tracker's records, ordered as its table, an id found with spaces or hyphens, and a closed one holding no issue done.
+func TestADesignsMilestonesAreTheTrackersRecords(t *testing.T) {
 	content, _, err := progressRecords().Read(DesignsFolder + "/47-delivery-from-commit-to-delivered.md")
 	if err != nil {
 		t.Fatal(err)
 	}
 	d := parseDesign(DesignsFolder+"/47-delivery-from-commit-to-delivered.md", content)
-	if d.Number != 47 || d.Title != "Delivery: from a commit to delivered" || d.Status != "in-progress" || !contains(d.Decisions, "ADR 0276") {
-		t.Fatalf("design %d %q %q %v", d.Number, d.Title, d.Status, d.Decisions)
+	if d.Number != 47 || d.Title != "Delivery: from a commit to delivered" || d.Status != "in-progress" || !contains(d.Decisions, "ADR 0276") ||
+		len(d.Milestones) != 0 {
+		t.Fatalf("design %d %q %q %v, %d milestones read from hq", d.Number, d.Title, d.Status, d.Decisions, len(d.Milestones))
 	}
-	if len(d.Milestones) != 29 {
-		t.Fatalf("%d milestones", len(d.Milestones))
+	seats := newSeatsWorld(t)
+	k := &KB{Seats: seats.ask}
+	ds, err := k.withMilestones([]*Design{d}, 47)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(ds[0].Milestones) != 29 || len(d.Milestones) != 0 || seats.asked[MilestonesVerb] != 1 {
+		t.Fatalf("%d milestones; the cached design holds %d", len(ds[0].Milestones), len(d.Milestones))
 	}
 	for _, c := range []struct {
 		id   string
 		want []int
 	}{
 		{"1", []int{973, 525}},
-		{"2b", []int{1025, 1019}},
 		{"R6", []int{1942, 1945, 1943, 1944, 1946, 1906, 1130}},
 		{"r4d", []int{}},
 		{"3 fix", []int{1082, 1049, 1047, 1083, 1079, 1084}},
 	} {
-		m := d.milestone(c.id)
+		m := ds[0].milestone(c.id)
 		if m == nil {
 			t.Fatalf("no milestone %s", c.id)
 		}
@@ -163,25 +178,10 @@ func TestTheDesignReaderReadsTheMilestoneTable(t *testing.T) {
 			t.Errorf("milestone %s: %v, want %v", c.id, m.Issues, c.want)
 		}
 	}
-	if r4a := d.milestone("R4a"); len(r4a.Issues) != 14 || !containsInt(r4a.Issues, 1360) {
-		t.Errorf("R4a's range 1353 to 1364 read as %v", r4a.Issues)
-	}
-	warned := strings.Join(d.Warnings, "\n")
-	for _, w := range []string{"issue 1209 is in milestones R3b and R3c", "issue 971 is in milestones 6 and R4c",
-		`"1353 to 1364" is a range in words, read as the 12 issues`, "milestone R4d names no issue"} {
-		if !strings.Contains(warned, w) {
-			t.Errorf("no warning %q in\n%s", w, warned)
-		}
-	}
-	// Design 57's range with an exception, and a design with no milestone table.
-	content, _, _ = progressRecords().Read(DesignsFolder + "/57-building-config-and-provisioning.md")
-	d57 := parseDesign(DesignsFolder+"/57-building-config-and-provisioning.md", content)
-	if m := d57.milestone("1"); m == nil || containsInt(m.Issues, 659) || !containsInt(m.Issues, 678) || !containsInt(m.Issues, 685) {
-		t.Errorf("design 57 milestone 1: %+v", d57.Milestones)
-	}
-	content, _, _ = progressRecords().Read(DesignsFolder + "/53-the-issue-tracker.md")
-	if d53 := parseDesign(DesignsFolder+"/53-the-issue-tracker.md", content); len(d53.Milestones) != 0 || d53.Status != "in-progress" {
-		t.Errorf("design 53: %+v", d53.Milestones)
+	closed := &Design{Milestones: []Milestone{{ID: "6", Status: "closed", Reason: "folded into release 4"}, {ID: "R4d", Status: "open"}}}
+	items, _ := milestoneItems(closed, nil, nil)
+	if items[0].State != StateDone || items[1].State != StateWaiting {
+		t.Fatalf("%+v", items)
 	}
 }
 
@@ -207,8 +207,8 @@ func TestDesignsAreReadAgainOnlyWhenHqMoves(t *testing.T) {
 	if rec.reads != 3 {
 		t.Fatalf("read %d documents for the mesh, want 3", rec.reads)
 	}
-	if !strings.Contains(p.Tree, "3 designs in progress, 2 with milestones") || !strings.Contains(p.Tree, "design 47 · Delivery: from a commit to delivered") ||
-		!strings.Contains(p.Tree, "1 designs in progress name no milestones (issue 845): 53") {
+	if !strings.Contains(p.Tree, "3 designs in progress, 1 with milestones") || !strings.Contains(p.Tree, "design 47 · Delivery: from a commit to delivered") ||
+		!strings.Contains(p.Tree, "2 designs in progress name no milestones (issue 845): 53, 57") {
 		t.Fatalf("mesh:\n%s", p.Tree)
 	}
 	for range 2 {
@@ -303,7 +303,7 @@ func TestProgressOfADesignMinimalAndDetailed(t *testing.T) {
 		t.Fatal(err)
 	}
 	raw, _ := json.Marshal(p)
-	if len(raw) > DefaultBound || p.Detail != DetailMinimal || !strings.Contains(p.Source, "issue 1781") {
+	if len(raw) > DefaultBound || p.Detail != DetailMinimal || !strings.Contains(p.Source, "the issue tracker's milestone records of design 47") {
 		t.Fatalf("%d bytes, %s, %s", len(raw), p.Detail, p.Source)
 	}
 	if seats.asked["seat:issue-tracker.list"] != 1 || seats.asked["seat:mesh-delivery.deliveries"] != 0 || seats.asked["seat:issue-tracker.get"] != 0 {
@@ -316,7 +316,7 @@ func TestProgressOfADesignMinimalAndDetailed(t *testing.T) {
 	if !strings.HasPrefix(lines[0], "✗ design 47 · Delivery: from a commit to delivered — ") {
 		t.Fatalf("first line %q", lines[0])
 	}
-	for _, want := range []string{"✗ R6  4/7  1945 fixing since", "✗ 3 fix  0/1  1049 fixing, worker fix-chain-cat@shanks stale since"} {
+	for _, want := range []string{"✗ R6  4/7  1945 fixing since", "✗ 3-fix  0/1  1049 fixing, worker fix-chain-cat@shanks stale since"} {
 		if !strings.Contains(p.Tree, want) {
 			t.Errorf("no %q in\n%s", want, p.Tree)
 		}
@@ -346,7 +346,7 @@ func TestProgressOfADesignMinimalAndDetailed(t *testing.T) {
 	if raw, _ := json.Marshal(small); len(raw) > LeastBound || !strings.Contains(small.Cut, "raise bound") {
 		t.Fatalf("%d bytes within %d; cut %q", len(raw), LeastBound, small.Cut)
 	}
-	for _, bad := range []ProgressAsk{{Of: "design"}, {Of: "milestone 47/R99"}, {Of: "design 47", Detail: "full"}} {
+	for _, bad := range []ProgressAsk{{Of: "design"}, {Of: "milestone 47/R99"}, {Of: "design 47", Detail: "full"}, {Of: "design 57"}} {
 		if _, err := k.Progress(bad); err == nil {
 			t.Errorf("%+v was answered", bad)
 		}