e2e: avoid unset defaults in generated tests (#7145)

I've observed a few cases in tests that are probably wrong, and added
some tests to cover this.

test/e2e/generator/generate.go

@@ -286,6 +286,13 @@ func generateNode(
 		Perturb:          nodePerturbations.Choose(r),
 	}
 
+	if node.Mempool == "" {
+		node.Mempool = "v1"
+	}
+	if node.PrivvalProtocol == "" {
+		node.PrivvalProtocol = "file"
+	}
+
 	if startAt > 0 {
 		node.StateSync = nodeStateSyncs.Choose(r)
 		if manifest.InitialHeight-startAt <= 5 && node.StateSync == e2e.StateSyncDisabled {

test/e2e/generator/generate_test.go

@@ -26,15 +26,27 @@ func TestGenerator(t *testing.T) {
 					numStateSyncs++
 				}
 				t.Run(name, func(t *testing.T) {
-					if node.StartAt > m.InitialHeight+5 && !node.Stateless() {
-						require.NotEqual(t, node.StateSync, e2e.StateSyncDisabled)
+					t.Run("StateSync", func(t *testing.T) {
+						if node.StartAt > m.InitialHeight+5 && !node.Stateless() {
+							require.NotEqual(t, node.StateSync, e2e.StateSyncDisabled)
+						}
+						if node.StateSync != e2e.StateSyncDisabled {
+							require.Zero(t, node.Seeds, node.StateSync)
+							require.True(t, len(node.PersistentPeers) >= 2 || len(node.PersistentPeers) == 0,
+								"peers: %v", node.PersistentPeers)
+						}
+					})
+					if e2e.Mode(node.Mode) != e2e.ModeLight {
+						t.Run("Mempool", func(t *testing.T) {
+							require.NotZero(t, node.Mempool)
+						})
+						t.Run("PrivvalProtocol", func(t *testing.T) {
+							require.NotZero(t, node.PrivvalProtocol)
+						})
+						t.Run("BlockSync", func(t *testing.T) {
+							require.NotZero(t, node.BlockSync)
+						})
 					}
-					if node.StateSync != e2e.StateSyncDisabled {
-						require.Zero(t, node.Seeds, node.StateSync)
-						require.True(t, len(node.PersistentPeers) >= 2 || len(node.PersistentPeers) == 0,
-							"peers: %v", node.PersistentPeers)
-					}
-
 				})
 			}
 			require.True(t, numStateSyncs <= 2)