Put a broken module back at once, and excuse a wait only for a move that added an account group (hq issue 318 review)

cmd/mesh-controller/gate.go

@@ -119,6 +119,9 @@ type gateFacts struct {
 	healthErr error
 	// heldOn is, per "<module>@<machine>", the provider its findings are held under (ADR 0240 rule 5).
 	heldOn map[string]string
+	// groupsAdded is, per module, whether the move judged puts an account in a group its previous build did
+	// not (issue 318 review): the only move whose wait for a new login is excused.
+	groupsAdded map[string]bool
 }
 
 // gatherGateFacts reads what a judging needs, from the store, the bus and this controller's memory. A
@@ -430,6 +433,7 @@ func judgeMoves(ctx context.Context, open *stores, g *inventory.PlanGate, pairs
 	if err != nil {
 		return "", err
 	}
+	facts.groupsAdded = movesAddingGroups(ctx, open.inventory, g, pairs, shelf)
 	// **What is wrong with a machine itself is the machine's** (novox/hq issue 281): read once for each
 	// machine judged, apart from what is wrong with a module there, and never pinned on the module the
 	// gate happens to be kept on.
@@ -544,7 +548,8 @@ func judgeMoves(ctx context.Context, open *stores, g *inventory.PlanGate, pairs
 			fail(g.BrokenWhy)
 			break
 		}
-		// What broke fails the send; what is beside it is judged to its own verdict first, within the bound.
+		// What broke fails the send, and is put back at once by the caller (putBackBroken); what is beside
+		// it is judged to its own verdict first, within the bound.
 		g.Passes, g.LastPass, g.Failing = 0, nil, failing
 		g.Last = fmt.Sprintf("%s; %s judged to its own verdict before the send's", g.BrokenWhy, strings.Join(judging, ", "))
 	case worst == healthWaiting:
@@ -607,6 +612,37 @@ func joinSaid(a, b string) string {
 	return a + "; " + b
 }
 
+// movesAddingGroups is, per module a gate judges, whether its move puts an account in a group the build it
+// moved from did not: read from the builds' manifests. A module whose move is not known adds none.
+func movesAddingGroups(ctx context.Context, inv *inventory.Inventory, g *inventory.PlanGate, pairs []judged,
+	shelf map[string]catalogue.Manifest) map[string]bool {
+	out := map[string]bool{}
+	for _, j := range pairs {
+		if _, done := out[j.module]; done {
+			continue
+		}
+		from, to := g.From, g.To
+		for _, c := range g.Carried {
+			if c.Module == j.module {
+				from, to = c.From, c.To
+				break
+			}
+		}
+		target, found, err := inv.ManifestAt(ctx, j.module, to)
+		if err != nil || !found {
+			target = shelf[j.module]
+		}
+		before, had, err := inv.ManifestAt(ctx, j.module, from)
+		if err != nil || (from != "" && !had) {
+			// What it moved from is not known: no wait is excused, rather than one the move did not bring.
+			out[j.module] = false
+			continue
+		}
+		out[j.module] = addsAccountGroups(before, had, target)
+	}
+	return out
+}
+
 // decide sets a gate's verdict.
 func decide(g *inventory.PlanGate, verdict, why string, now time.Time) {
 	g.Verdict, g.Why, g.JudgedAt = verdict, why, &now