fix(nodebuilder/tests): fix TestShrexFromLights and TestArchivalBlobSync flakes

TestShrexFromLights: restructure to start light node after blocks are
filled so initial header exchange sync fetches all needed headers without
relying on gossipsub (same pattern that fixed TestShrexFromLightsWithBadFulls).

TestArchivalBlobSync: close the stopped archivalBN's host so that future
createPeer/LinkAll calls don't re-link new nodes to it. Without this,
new nodes may inadvertently reach archivalBN via shrex and get "protocols
not supported" errors since its handlers are gone after Stop().

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: rootulp

nodebuilder/tests/prune_test.go

@@ -102,10 +102,15 @@ func TestArchivalBlobSync(t *testing.T) {
 	require.NoError(t, err)
 	err = archivalBN.Stop(ctx)
 	require.NoError(t, err)
+	// Close the stopped archivalBN's host so that future createPeer/LinkAll
+	// calls don't re-link new nodes to it. Without this, new nodes may try
+	// to reach archivalBN via shrex and get "protocols not supported" errors
+	// since its handlers are gone.
+	err = archivalBN.Host.Close()
+	require.NoError(t, err)
 
 	// Reset bootstrappers to exclude the stopped archivalBN. Keep only archivalFN
-	// so new nodes don't attempt connections to the stopped node (which causes
-	// "protocol not supported" errors).
+	// so new nodes don't attempt connections to the stopped node.
 	sw.Bootstrappers = sw.Bootstrappers[:0]
 	sw.SetBootstrapper(t, archivalFN)
 

nodebuilder/tests/shrex_test.go

@@ -41,22 +41,33 @@ func TestShrexFromLights(t *testing.T) {
 	bridge := sw.NewBridgeNode()
 	sw.SetBootstrapper(t, bridge)
 
-	cfg := sw.DefaultTestConfig(node.Light)
-	cfg.Share.Discovery.PeersLimit = 1
-	light := sw.NewNodeWithConfig(node.Light, cfg)
-
 	err := bridge.Start(ctx)
 	require.NoError(t, err)
-	err = light.Start(ctx)
-	require.NoError(t, err)
 
 	bridgeClient := getAdminClient(ctx, bridge, t)
-	lightClient := getAdminClient(ctx, light, t)
 
 	// wait for chain to be filled
 	require.NoError(t, <-fillDn)
 
-	for i := range heightsCh {
+	// Collect all filled block heights and wait for bridge to sync them
+	heights := make([]uint64, 0, blocks)
+	for h := range heightsCh {
+		heights = append(heights, h)
+	}
+	_, err = bridgeClient.Header.WaitForHeight(ctx, heights[len(heights)-1])
+	require.NoError(t, err)
+
+	// Start the light node after blocks are filled so its initial header
+	// exchange sync fetches all needed headers without relying on gossipsub.
+	cfg := sw.DefaultTestConfig(node.Light)
+	cfg.Share.Discovery.PeersLimit = 1
+	light := sw.NewNodeWithConfig(node.Light, cfg)
+	err = light.Start(ctx)
+	require.NoError(t, err)
+
+	lightClient := getAdminClient(ctx, light, t)
+
+	for _, i := range heights {
 		h, err := bridgeClient.Header.GetByHeight(ctx, i)
 		require.NoError(t, err)