Wait for the whole start pass before serving a served test, so a rotation test never reads it midway (issue 1945)

cmd/mesh-controller/composed_served_integration_test.go

@@ -240,10 +240,16 @@ func aServedMesh(t *testing.T) *servedMesh {
 		}
 		handingOver.Store(false)
 	})
-	// Served once both nodes have their own composition: the start's pass ran.
-	for _, node := range []string{"anchor", "laptop"} {
-		own, _ := sdkdelivery.ComposedNodeKey(node)
-		m.waitFor(t, done, node, own, 0)
+	// Served once both nodes have their own composition and their module's: the start's pass wrote them all. A node's
+	// compositions are written in key order, so anchor's own comes before its store's (issue 1945: a test that reads the
+	// revisions at once must not catch the pass midway).
+	for _, k := range []struct{ node, module, fp string }{{"anchor", "", ""}, {"laptop", "", ""}, {"anchor", "store", fpOf('a')},
+		{"laptop", "board", fpOf('b')}} {
+		key, _ := sdkdelivery.ComposedNodeKey(k.node)
+		if k.module != "" {
+			key, _ = sdkdelivery.ComposedKey(k.node, k.module, k.fp)
+		}
+		m.waitFor(t, done, k.node, key, 0)
 	}
 	return m
 }