mesh-delivery: a merge that starts over a stopped duplicate is made from the forge's word too (issue 783)

modules/mesh-delivery/cmd/mesh-delivery/holder.go

@@ -524,15 +524,23 @@ func (h *Holder) PullMerged(p PullEvent) {
 	if over := startedOverFor(d, p.Number); over != "" {
 		// A delivery stopped only by an earlier, closed duplicate pull request with the same head is not lost when
 		// its merge is heard without the open announcement either: it is started over for the merging pull request
-		// the same way an announcement would, before the merge is taken as usual (novox/hq issue 783).
+		// the same way an announcement would, before the merge is taken as usual (novox/hq issue 783). Heard this
+		// way — its own merge, with no open announcement of this pull request — it is made exactly as a first-heard
+		// merge in every field but its id: FromForge, and its check the forge's word on the head, so a long-past
+		// merge replayed from the bus's history still falls under the history rule (issue 313) and is not held for
+		// a person (review round 1).
 		fresh, t, err := h.freshAnnouncement(p, now, over)
 		if err != nil {
 			h.refuse(err)
 			return
 		}
+		fresh.FromForge = true
+		if s := p.HeadChecks["mesh/merge-gate"]; s != "" {
+			fresh.Check = &Verdict{At: now, Gate: verdictOfState(s), Summary: "the head's mesh/merge-gate, as the forge holds it",
+				Repo: verdictOfState(p.HeadChecks["mesh/repo-check"])}
+		}
 		d, ts = fresh, []Transition{t}
-		if v := decidedOnHead(p.HeadChecks, now); v != nil {
-			d.Check = v
+		if d.Check != nil {
 			ts = append(ts, settle(d, Facts{Now: now})...)
 		}
 	} else if d == nil {

modules/mesh-delivery/cmd/mesh-delivery/issue783_test.go

@@ -3,6 +3,7 @@ package main
 import (
 	"strings"
 	"testing"
+	"time"
 )
 
 // novox/hq issue 783: mesh-catalog commit b5417c28 was pushed while #305 (from branch adr-359-mesh-mail-733) was
@@ -20,6 +21,7 @@ const (
 	head783, merge783   = "d305d305d305d305", "d315d315d315d315"
 	head783b, merge783b = "d306d306d306d306", "d316d316d316d316"
 	head783c            = "d307d307d307d307"
+	head783d, merge783d = "d308d308d308d308", "d318d318d318d318"
 	catalog783          = "novox/mesh-catalog"
 	branch783           = "adr-359-mesh-mail-733"
 )
@@ -113,3 +115,37 @@ func TestAStoppedDeliveryAnnouncedAgainByItsOwnPullRequestStaysStopped(t *testin
 		t.Fatalf("#307 announced again by itself left it %s, Number %d; want it to stay stopped", d.State, d.Number)
 	}
 }
+
+// TestAMergeHeardLongAfterStartingOverAStoppedDuplicateIsHistoryLikeAnyOtherReplayedMerge is review round 1's
+// decision: a delivery started over from a merge heard without its open announcement (as in decision 4, above)
+// takes FromForge exactly as a first-heard merge does, so one replayed from the bus's history long after it
+// happened still falls under the history rule (novox/hq issue 313) and is never held for a person.
+func TestAMergeHeardLongAfterStartingOverAStoppedDuplicateIsHistoryLikeAnyOtherReplayedMerge(t *testing.T) {
+	w := newWorld(t)
+	id := IDOf(catalog783, head783d)
+
+	w.h.PullUpdated(pr(catalog783, 308, head783d, branch783+"-d", "src/d.go"))
+	w.h.PullClosed(pr(catalog783, 308, head783d, branch783+"-d"))
+	if w.state(id) != Stopped {
+		t.Fatalf("#308 closed unmerged left it %s; want stopped", w.state(id))
+	}
+
+	m := merged(catalog783, 318, head783d, merge783d)
+	m.MergedAt = w.now.Add(-historyLate - time.Minute).UTC().Format(time.RFC3339)
+	w.h.PullMerged(m)
+
+	d := w.delivery(id)
+	if d.State == Stopped || d.Number != 318 {
+		t.Fatalf("#318's merge, heard long after it happened with no announcement of its own, left it %s, Number %d; "+
+			"want started over for #318", d.State, d.Number)
+	}
+	if !d.FromForge {
+		t.Fatal("a merge heard without its own announcement is made from the forge's word: FromForge is false")
+	}
+	if d.History == "" {
+		t.Fatalf("a merge heard %s after it happened is history, never held for a person; History is empty", historyLate+time.Minute)
+	}
+	if d.State == Held {
+		t.Fatalf("history is never held for a person; state is %s, HeldWhy %q", d.State, d.HeldWhy)
+	}
+}