From c072a271e583cf9dc55c0a3ea73af3c6544783b0 Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Mon, 9 Nov 2026 23:17:05 +0100
Subject: [PATCH] =?UTF-8?q?D4b:=20a=20row=20that=20a=20candidate=20taken?=
 =?UTF-8?q?=20out=20ends=20its=20check=20with=20a=20named=20cause,=20so=20?=
 =?UTF-8?q?the=20asker=20drops=20its=20asks=20(ADR=200664=20=C2=A75,=20iss?=
 =?UTF-8?q?ue=201748)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Claude-Session: https://claude.ai/code/session_01JG73KEq4zoDfM9WtYpcQgZ
---
 .../internal/check/checker_test.go                | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/modules/mesh-delivery-checker/internal/check/checker_test.go b/modules/mesh-delivery-checker/internal/check/checker_test.go
index e644894b..e33901e1 100644
--- a/modules/mesh-delivery-checker/internal/check/checker_test.go
+++ b/modules/mesh-delivery-checker/internal/check/checker_test.go
@@ -3,6 +3,7 @@ package check
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"strings"
 	"sync"
@@ -362,6 +363,20 @@ func TestARepositoryWithNoTrunkCannotBeJudgedLoudlyUntilItsTrunkIsKnown(t *testi
 			}
 		})
 	}
+
+	// ADR 0664 §5 (issue 1748): a candidate taken out (its pull request merged or closed) ends the check running for it with a
+	// cause its asks' wait names, never a plain cancel, so its asker drops the asks it put on the build nodes.
+	t.Run("a candidate taken out ends its check with a named cause", func(t *testing.T) {
+		ch := &Checker{}
+		ch.init()
+		run, end := context.WithCancelCause(context.Background())
+		ch.live["g.heads"] = liveCheck{group: "g", end: end}
+		ch.Forget("g")
+		var s superseded
+		if cause := context.Cause(run); !errors.As(cause, &s) || s.by != "" || errors.Is(cause, context.Canceled) {
+			t.Errorf("the check was ended with %v, want superseded with no heads, not a plain cancel", cause)
+		}
+	})
 }
 
 func countWith(lines []string, words string) int {