From 3579a5075ce13fd1d8e139ffbc5d7065cd00fedf Mon Sep 17 00:00:00 2001
From: Alan Fitzgerald <alanfitzgerald@gmail.com>
Date: Wed, 30 Sep 2026 10:59:28 -0400
Subject: [PATCH] fix(prstatus): ignore CI runs superseded by a newer run of
 the same job

A run cancelled by a newer one (concurrency group, manual re-run) stays in
statusCheckRollup next to its replacement, and aggregateCI counted its
CANCELLED conclusion as a failure, so a green PR showed as failing.
Keep only the latest run per workflow+job before aggregating.
---
 internal/prstatus/prstatus.go      | 40 +++++++++++++++++++++++++++++-
 internal/prstatus/prstatus_test.go | 24 ++++++++++++++++++
 2 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/internal/prstatus/prstatus.go b/internal/prstatus/prstatus.go
index d34fc03..45f04b5 100644
--- a/internal/prstatus/prstatus.go
+++ b/internal/prstatus/prstatus.go
@@ -88,6 +88,12 @@ type rawCheck struct {
 	Status     string `json:"status"`
 	Conclusion string `json:"conclusion"`
 	State      string `json:"state"`
+	// Name, WorkflowName and StartedAt identify re-runs of the same job:
+	// a run cancelled by a newer one (a concurrency group, a manual
+	// re-run) stays in the rollup alongside its replacement.
+	Name         string `json:"name"`
+	WorkflowName string `json:"workflowName"`
+	StartedAt    string `json:"startedAt"`
 }
 
 // Fetch reports on a pull request via the gh CLI. With prURL set it looks up
@@ -201,7 +207,7 @@ func aggregateCI(checks []rawCheck) string {
 		return "NONE"
 	}
 	pending := false
-	for _, c := range checks {
+	for _, c := range latestRuns(checks) {
 		if c.Typename == "StatusContext" {
 			switch c.State {
 			case "FAILURE", "ERROR":
@@ -227,3 +233,35 @@ func aggregateCI(checks []rawCheck) string {
 	}
 	return "PASSING"
 }
+
+// latestRuns drops CheckRuns superseded by a newer run of the same job, so a
+// run cancelled in favour of its replacement doesn't mark the PR failing.
+// Unnamed checks and StatusContexts (already latest-per-context) pass through.
+func latestRuns(checks []rawCheck) []rawCheck {
+	started := func(c rawCheck) string {
+		// A queued run has no start time yet (or Go's zero time) but is
+		// the newest of its job.
+		if c.StartedAt == "" || strings.HasPrefix(c.StartedAt, "0001-") {
+			return "9999"
+		}
+		return c.StartedAt // RFC 3339 UTC, so it sorts as a string
+	}
+	latest := map[string]int{}
+	var out []rawCheck
+	for _, c := range checks {
+		if c.Typename == "StatusContext" || c.Name == "" {
+			out = append(out, c)
+			continue
+		}
+		key := c.WorkflowName + "\x00" + c.Name
+		if i, ok := latest[key]; ok {
+			if started(c) > started(out[i]) {
+				out[i] = c
+			}
+			continue
+		}
+		latest[key] = len(out)
+		out = append(out, c)
+	}
+	return out
+}
diff --git a/internal/prstatus/prstatus_test.go b/internal/prstatus/prstatus_test.go
index 5620552..f2614f8 100644
--- a/internal/prstatus/prstatus_test.go
+++ b/internal/prstatus/prstatus_test.go
@@ -140,6 +140,30 @@ func TestAggregateCI(t *testing.T) {
 			[]rawCheck{{Status: "IN_PROGRESS"}, {Status: "COMPLETED", Conclusion: "FAILURE"}},
 			"FAILING",
 		},
+		{
+			"run cancelled by a newer successful run of the same job",
+			[]rawCheck{
+				{Name: "build", WorkflowName: "CI", StartedAt: "2026-09-30T12:55:43Z", Status: "COMPLETED", Conclusion: "CANCELLED"},
+				{Name: "build", WorkflowName: "CI", StartedAt: "2026-09-30T12:55:49Z", Status: "COMPLETED", Conclusion: "SUCCESS"},
+			},
+			"PASSING",
+		},
+		{
+			"newer run of a job is queued, older one failed",
+			[]rawCheck{
+				{Name: "build", WorkflowName: "CI", StartedAt: "2026-09-30T12:55:43Z", Status: "COMPLETED", Conclusion: "FAILURE"},
+				{Name: "build", WorkflowName: "CI", StartedAt: "0001-01-01T00:00:00Z", Status: "QUEUED"},
+			},
+			"PENDING",
+		},
+		{
+			"latest run of a job cancelled still fails",
+			[]rawCheck{
+				{Name: "build", WorkflowName: "CI", StartedAt: "2026-09-30T12:55:49Z", Status: "COMPLETED", Conclusion: "CANCELLED"},
+				{Name: "build", WorkflowName: "CI", StartedAt: "2026-09-30T12:55:43Z", Status: "COMPLETED", Conclusion: "SUCCESS"},
+			},
+			"FAILING",
+		},
 		{
 			"legacy StatusContext failure",
 			[]rawCheck{{Typename: "StatusContext", State: "FAILURE"}},