From 3c6f000eca79d4e319486612e9b2a889246c2479 Mon Sep 17 00:00:00 2001
From: sneak <sneak@sneak.berlin>
Date: Wed, 11 Nov 2026 04:52:46 +0000
Subject: [PATCH] sww tests: wait for the starting line as long as the start
 takes (closes #324)

A start on a loaded host can take longer than the 10-second wait for
a line. The new output.lineBeforeExit waits until the line is written
or sww exits, so only the test binary's own timeout ends the wait. It
replaces the waits that span the start in runUntilStopped,
TestServesUntilToldToStop and TestLogLevelHoldsBackTheLessSevereProcessLines.

Model: opus-5-5
---
 internal/sww/sww_test.go | 34 ++++++++++++++++++++++++++++++----
 1 file changed, 30 insertions(+), 4 deletions(-)

diff --git a/internal/sww/sww_test.go b/internal/sww/sww_test.go
index 84b9b1f..fbff72f 100644
--- a/internal/sww/sww_test.go
+++ b/internal/sww/sww_test.go
@@ -92,6 +92,31 @@ func (o *output) line(t *testing.T, key, value string) map[string]any {
 	return nil
 }
 
+// lineBeforeExit returns the first line whose msg is msg, waiting for it
+// while sww runs. It waits as long as that takes, so that a slow start
+// cannot fail the test, and fails the test if sww exits first.
+func (o *output) lineBeforeExit(
+	t *testing.T, msg string, exited <-chan int,
+) map[string]any {
+	t.Helper()
+
+	for {
+		fields := o.findLine(t, func(fields map[string]any) bool {
+			return fields["msg"] == msg
+		})
+		if fields != nil {
+			return fields
+		}
+
+		select {
+		case status := <-exited:
+			t.Fatalf("exit status %d while waiting for a line with msg %q; output:\n%s",
+				status, msg, o.text())
+		case <-time.After(pollInterval):
+		}
+	}
+}
+
 // findLine returns the first line written so far for which matches is true, or
 // nil.
 func (o *output) findLine(
@@ -236,11 +261,12 @@ func TestServesUntilToldToStop(t *testing.T) {
 	}()
 
 	// The default rule file is read.
-	if rules := out.line(t, "msg", "read the rule files")["rules"]; rules != 12.0 {
+	readRules := out.lineBeforeExit(t, "read the rule files", exited)
+	if rules := readRules["rules"]; rules != 12.0 {
 		t.Errorf("read %v rules from the default rule file, want 12", rules)
 	}
 
-	starting := out.line(t, "msg", "starting")
+	starting := out.lineBeforeExit(t, "starting", exited)
 	wantStartingLine(t, starting, dir)
 
 	addr, _ := starting["address"].(string)
@@ -286,7 +312,7 @@ func TestLogLevelHoldsBackTheLessSevereProcessLines(t *testing.T) {
 		}, out)
 	}()
 
-	out.line(t, "msg", "fetching a list failed")
+	out.lineBeforeExit(t, "fetching a list failed", exited)
 	stop()
 
 	select {
@@ -1261,7 +1287,7 @@ func runUntilStopped(
 		exited <- run(ctx, env, out)
 	}()
 
-	addr, _ := out.line(t, "msg", "starting")["address"].(string)
+	addr, _ := out.lineBeforeExit(t, "starting", exited)["address"].(string)
 	use("http://" + addr + "/")
 	stop()
 
-- 
2.54.0