fix: prevent SIGTERM/reload deadlock (#7562)

plugin/reload/reload_test.go

@@ -0,0 +1,50 @@
+package reload
+
+import (
+	"testing"
+
+	"github.com/coredns/caddy"
+)
+
+// fakeInput implements caddy.Input for testing parse().
+type fakeInput struct {
+	p string
+	b []byte
+}
+
+func (f fakeInput) ServerType() string { return "dns" }
+func (f fakeInput) Body() []byte       { return f.b }
+func (f fakeInput) Path() string       { return f.p }
+
+// TestParseInvalidCorefile ensures parse returns an error for invalid Corefile syntax.
+func TestParseInvalidCorefile(t *testing.T) {
+	t.Parallel()
+
+	broken := fakeInput{p: "Corefile", b: []byte(". { errors\n")}
+	if _, err := parse(broken); err == nil {
+		t.Fatalf("expected parse error for invalid Corefile, got nil")
+	}
+}
+
+// TestShutdownGate ensures the shutdown gate helper recognizes when shutdown is requested.
+func TestShutdownGate(t *testing.T) {
+	t.Parallel()
+
+	q := make(chan bool, 1)
+	if shutdownRequested(q) {
+		t.Fatalf("expected no shutdown before signal")
+	}
+	q <- true
+	if !shutdownRequested(q) {
+		t.Fatalf("expected shutdown after signal")
+	}
+}
+
+// TestHookIgnoresNonStartupEvent ensures hook is a no-op for non-startup events.
+func TestHookIgnoresNonStartupEvent(t *testing.T) {
+	t.Parallel()
+
+	if err := hook(caddy.EventName("not-startup"), nil); err != nil {
+		t.Fatalf("expected no error for non-startup event, got %v", err)
+	}
+}