gate: an approved merge whose trunk moved waits for its carried verdict and merges on it with no second ask, never on the old one (ADR 0548 §8; issue 568 G4)

2026-10-26 11:43:18 +01:00
parent c8e1e2b2fa
commit 100e74f283
3 changed files with 42 additions and 11 deletions
@@ -164,6 +164,45 @@ func TestOneCheckPerDeliveryAtTheGate(t *testing.T) {
 				t.Fatalf("merges %v; the turns were %q, want %q", w.forge.merges, turns.said(), want)
 			}
 		},
+		// §8: an approved delivery whose trunk moved goes back to proposed, waits for its carried verdict rather than being
+		// handed on the old one, and merges on it with no second ask.
+		"an approved merge whose trunk moved merges on its carried verdict with no second ask": func(t *testing.T) {
+			w := newWorld(t)
+			putCheckerVerdict(w, "running", headOf(oneRepo, 9, otherHead)) // holds the approved merge (§2)
+			id := approvedLone(w)
+			w.settleAll()
+			if w.op.count() != 1 || len(w.forge.merges) != 0 {
+				t.Fatalf("asked %d times, merges %v; want approved and held", w.op.count(), w.forge.merges)
+			}
+			w.h.PullMerged(merged(oneRepo, 5, otherHead, oneTrunk2)) // a merge at the forge moves the trunk
+			putCheckerVerdict(w, "pass", headOf(oneRepo, 9, otherHead))
+			w.settleAll()
+			if len(w.forge.merges) != 0 {
+				t.Fatalf("merges %v: handed on a verdict judged on the old trunk", w.forge.merges)
+			}
+			d := w.delivery(id)
+			if d.Ready == nil || !strings.Contains(d.Ready.Waits, "being carried") {
+				t.Fatalf("after the trunk moved it waits for %q, want its verdict carried", d.Ready.Waits)
+			}
+			// The checker's carried line: the head on the new trunk, carried from the old one.
+			carried := checkStatus(oneRepo, oneHead, "success", oneTrunk2)
+			carried.Description = "pass " + oneHead[:12] + " on " + oneTrunk2[:12] + " | carried from " + oneTrunk[:12] + " | unit 0 run, 4 kept"
+			if head, trunk := checkLine(carried.Description); head != oneHead[:12] || trunk != oneTrunk2[:12] {
+				t.Fatalf("the carried line reads as %s on %s", head, trunk)
+			}
+			if head, trunk := checkLine("failed: a test"); head != "" || trunk != "" {
+				t.Fatalf("a line that names no commits gave %q %q", head, trunk)
+			}
+			putCheckerVerdict(w, "pass", headOf(oneRepo, 1, oneHead))
+			w.h.CommitStatus(carried)
+			w.settleAll()
+			if w.op.count() != 1 {
+				t.Errorf("the Approve was asked %d times, want once: it stands through the carry", w.op.count())
+			}
+			if d := w.delivery(id); d.Check == nil || d.Check.Trunk != oneTrunk2[:12] || len(w.forge.merges) != 1 {
+				t.Errorf("after the carry: verdict %+v, merges %v; want merged on the carried verdict", d.Check, w.forge.merges)
+			}
+		},
 	} {
 		t.Run(name, run)
 	}
@@ -199,14 +199,3 @@ func TestAClosedPullRequestAsksNoForgetChecks(t *testing.T) {
 	w.h.PullUpdated(p)
 	w.h.PullClosed(p)
 }
-
-// 1302: the mesh/check line gives the head and the trunk it judged.
-func TestTheCheckLineGivesHeadAndTrunk(t *testing.T) {
-	head, trunk := checkLine("pass " + oneHead[:12] + " on " + oneTrunk[:12] + " | unit 4 run, 0 kept | group g of 2 pull requests")
-	if head != oneHead[:12] || trunk != oneTrunk[:12] {
-		t.Fatalf("head %q trunk %q", head, trunk)
-	}
-	if head, trunk = checkLine("failed: a test"); head != "" || trunk != "" {
-		t.Fatalf("a line that names no commits gave %q %q", head, trunk)
-	}
-}
@@ -387,6 +387,9 @@ func (h *Holder) readyWaits(d *Delivery) string {
 	case d.State == Proposed && d.outOfDate() != "" && d.AskedAgain != nil:
 		return "its check against the trunk's head is asked and has not answered"
 	case d.State == Proposed && d.outOfDate() != "" && d.Check.Passes() && h.covering(d) != nil:
+		// Approved, and its trunk moved: the checker carries its verdict to the trunk's head by its package digests (ADR 0548
+		// §5, §8). The Approve stands and is not asked again; the merge waits for the carried verdict, not a fresh check.
+		return "approved; its verdict is being carried to the trunk's head " + shortOf(d.TrunkNow, 12) + " (" + d.outOfDate() + ")"
 	case d.State == Proposed && d.outOfDate() != "":
 		return "its verdict is out of date: its check against the trunk's head is asked before the operator is"
 	case d.State == Proposed && d.AskedAgain != nil: