Judge a resume only by the builds its tier holds, and ask build-agent's own of build-agent (issue 1886, review round 1)

cmd/mesh-controller/plan_retry.go

@@ -210,7 +210,7 @@ func retryRefusal(p inventory.Plan, plans []inventory.Plan, onPath map[string]st
 			return fmt.Errorf("%s supersedes it: a newer merge of %s (%s at %s) is open, and resuming %s would build "+
 				"what that one replaced", q.ID, q.Repository, q.ID, short(q.Commit), p.ID)
 		}
-		for _, m := range yetToSend(p) {
+		for _, m := range holdingABuild(p) {
 			if q, found := newerPlanFor(m, p, plans); found {
 				return fmt.Errorf("%s has a newer plan, %s (%s, %s at %s): resuming %s would send the older build of it "+
 					"over the newer one", m, q.ID, q.State, q.Repository, short(q.Commit), p.ID)
@@ -639,25 +639,42 @@ func waitingIn(p inventory.Plan) (asked, unsent, unasked int) {
 	return asked, unsent, unasked
 }
 
-// yetToSend is every module a stopped walk has still to send: its current tier's modules not sent and every module of
-// the tiers after, sorted.
-func yetToSend(p inventory.Plan) []string {
+// holdingABuild is the modules of a stopped walk's current tier that hold a build of its commit, not yet sent: built and
+// not sent, or asked under a build id. Only these could put an older build over a newer plan's (review of issue 1886): a
+// module not yet asked is asked at its followed branch's head when the walk reaches it, and one asked on the builder's key
+// is settled by the look from the key of the commit it reads then. Sorted.
+func holdingABuild(p inventory.Plan) []string {
+	if p.Tier >= len(p.Tiers) {
+		return nil
+	}
 	var out []string
-	for i := p.Tier; i < len(p.Tiers); i++ {
-		for _, m := range p.Tiers[i] {
-			if s := p.Modules[m]; i > p.Tier || s == nil || s.SentAt == nil {
-				out = append(out, m)
-			}
+	for _, m := range p.Tiers[p.Tier] {
+		s := p.Modules[m]
+		if s == nil || s.SentAt != nil || s.Key {
+			continue
+		}
+		if s.State == "built" || (s.State == "asked" && s.Build != "") {
+			out = append(out, m)
 		}
 	}
 	sort.Strings(out)
 	return out
 }
 
-// resumeStopped sets a walk stopped by hand building again at the tier it stopped at, its stop cleared and its asks kept
-// (issue 1886): the next look carries it on as any walk — a build done waits for its reference, and one done on the
+// resumeStopped sets a walk stopped by hand building again at the tier it stopped at, its stop cleared and its asks kept but
+// build-agent's own (issue 1886): the next look carries it on as any walk — a build done waits for its reference, and one done on the
 // builder's key is handed on (novox/hq ADR 0522 §3). Its note keeps who stopped it and that a person resumed it.
 func resumeStopped(p *inventory.Plan) string {
+	// **Build-agent's own are asked of build-agent** (novox/hq ADR 0522 §6): one marked taken from a key it writes itself is
+	// set unasked, and the look asks the rest of a partly asked tier (unaskedOf), of build-agent, whatever the builder says.
+	var again []string
+	for _, m := range p.Tiers[p.Tier] {
+		if s := p.Modules[m]; s != nil && s.State == "asked" && s.Key && isBuildersOwn(m) {
+			s.State, s.Key, s.AskedAt, s.Build, s.Why = "", false, nil, "", ""
+			again = append(again, m)
+		}
+	}
+	sort.Strings(again)
 	asked, unsent, unasked := waitingIn(*p)
 	later := 0
 	for i := p.Tier + 1; i < len(p.Tiers); i++ {
@@ -666,10 +683,13 @@ func resumeStopped(p *inventory.Plan) string {
 	by, why := p.Delivery.Stopped, p.Delivery.StoppedWhy
 	waits := fmt.Sprintf("%d asked, %d built and not sent, %d not yet asked in it; %d not yet asked in the tiers after",
 		asked, unsent, unasked, later)
+	if len(again) > 0 {
+		waits += "; " + strings.Join(again, ", ") + " set unasked, for the look to ask of build-agent (its own, ADR 0522 §6)"
+	}
 	p.State = inventory.PlanBuilding
 	goesOnAgain(p)
 	p.Delivery.Kept = nil
 	p.Note = fmt.Sprintf("tier %d resumed by hand after the stop by %s (%s): %s", p.Tier, by, why, waits)
-	return fmt.Sprintf("%s resumed at tier %d of %d, stopped by %s: %s; nothing asked again — the next look carries it "+
+	return fmt.Sprintf("%s resumed at tier %d of %d, stopped by %s: %s; this verb asks nothing — the next look carries it "+
 		"on as any walk", p.ID, p.Tier+1, len(p.Tiers), by, waits)
 }

cmd/mesh-controller/plan_retry_stopped_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -28,7 +29,7 @@ func TestRetryResumesAWalkStoppedByHand(t *testing.T) {
 	var tier1 []string
 	for _, m := range []string{"build-agent", "mesh-tools"} {
 		tier1 = append(tier1, m)
-		p.Modules[m] = &inventory.PlanModule{State: "built", BuiltAt: &sent}
+		p.Modules[m] = &inventory.PlanModule{State: "built", AskedAt: &sent, BuiltAt: &sent, Build: "build-" + m}
 	}
 	onKeys := []string{"mesh-build-go", "mesh-build-image", "mesh-build-node", "mesh-delivery-checker",
 		"mesh-delivery-forge-bridge", "mesh-delivery-gate", "mesh-delivery-indexer", "mesh-delivery-view"}
@@ -56,11 +57,23 @@ func TestRetryResumesAWalkStoppedByHand(t *testing.T) {
 		t.Errorf("the note does not record the hand resume and the stop it undid: %q", p.Note)
 	}
 	for _, m := range onKeys {
-		if s := p.Modules[m]; s.State != "asked" || !s.Key || s.Build != "build-"+m {
+		s := p.Modules[m]
+		if isBuildersOwn(m) {
+			// Build-agent's own are asked of build-agent whatever the builder says (ADR 0522 §6): set unasked, for the look.
+			if s.State != "" || s.Key || s.Build != "" || s.AskedAt != nil {
+				t.Errorf("%s, build-agent's own, was left on the builder's key: %+v", m, s)
+			}
+			if !slices.Contains(unaskedOf(p), m) {
+				t.Errorf("%s is not among what the look asks next: %v", m, unaskedOf(p))
+			}
+			continue
+		}
+		if s.State != "asked" || !s.Key || s.Build != "build-"+m {
 			t.Errorf("%s's ask was not kept for the look to hand on: %+v", m, s)
 		}
 	}
-	for _, w := range []string{"plan-r4e", "tier 2 of 3", "8 asked", "2 built and not sent", "3 not yet asked"} {
+	for _, w := range []string{"plan-r4e", "tier 2 of 3", "5 asked", "2 built and not sent", "3 not yet asked in it",
+		"3 not yet asked in the tiers after", "mesh-build-go, mesh-build-image, mesh-build-node set unasked"} {
 		if !strings.Contains(said, w) {
 			t.Errorf("the answer %q does not say %q", said, w)
 		}
@@ -87,3 +100,40 @@ func TestRetryResumesAWalkStoppedByHand(t *testing.T) {
 		t.Errorf("a stopped walk was resumed beside a related open walk: %v", err)
 	}
 }
+
+// A newer plan holding a module the stopped walk has not yet asked does not refuse its resume (review of issue 1886): that
+// module is asked at its followed branch's head when the walk reaches it, so no older build goes over the newer. Open and
+// related, the newer walk refuses it under one walk at a time; done, it does not. One holding a build the walk has not sent
+// still refuses it.
+func TestResumeIsNotRefusedByANewerPlanOfAModuleNotYetAsked(t *testing.T) {
+	at := time.Date(2026, 10, 23, 0, 1, 53, 0, time.UTC)
+	sent := at.Add(-time.Hour)
+	p := inventory.Plan{ID: "plan-r4e", Repository: "novox/mesh-sdk", Branch: "main", Commit: "7aacbc16",
+		Created: at.Add(-2 * time.Hour), State: inventory.PlanFailed, Tier: 1,
+		Delivery: &inventory.PlanDelivery{Stopped: "a person", StoppedWhy: "issue 1886"},
+		Tiers:    [][]string{{"mesh-sdk"}, {"build-agent", "mesh-delivery-gate"}, {"mesh-delivery-builder", "gitea"}},
+		Modules: map[string]*inventory.PlanModule{
+			"mesh-sdk":              {State: "built", BuiltAt: &sent, SentAt: &sent},
+			"build-agent":           {State: "built", BuiltAt: &sent},
+			"mesh-delivery-gate":    {State: "asked", AskedAt: &sent, Key: true},
+			"mesh-delivery-builder": {}, "gitea": {}}}
+	newer := func(state string, holds string) inventory.Plan {
+		return inventory.Plan{ID: "plan-1792715180015327197", Repository: "novox/mesh-delivery", Branch: "main",
+			Commit: "d00dfeed", Created: at, State: state, Tiers: [][]string{{holds}},
+			Modules: map[string]*inventory.PlanModule{holds: {State: "asked"}}}
+	}
+	if err := retryRefusal(p, []inventory.Plan{p, newer(inventory.PlanDone, "mesh-delivery-builder")}, ownPathOf(nil)); err != nil {
+		t.Errorf("a done newer plan of a module not yet asked refused the resume: %v", err)
+	}
+	if err := retryRefusal(p, []inventory.Plan{p, newer(inventory.PlanDone, "mesh-delivery-gate")}, ownPathOf(nil)); err != nil {
+		t.Errorf("a done newer plan of a module on the builder's key refused the resume: %v", err)
+	}
+	if err := retryRefusal(p, []inventory.Plan{p, newer(inventory.PlanBuilding, "mesh-delivery-builder")}, ownPathOf(nil)); err == nil ||
+		!strings.Contains(err.Error(), "one walk at a time") {
+		t.Errorf("an open newer walk related to it did not refuse the resume under one walk at a time: %v", err)
+	}
+	if err := retryRefusal(p, []inventory.Plan{p, newer(inventory.PlanDone, "build-agent")}, ownPathOf(nil)); err == nil ||
+		!strings.Contains(err.Error(), "older build") {
+		t.Errorf("a newer plan of a built module not yet sent did not refuse the resume: %v", err)
+	}
+}