php8: resolve union types in NamespaceResolver

pkg/visitor/nsresolver/namespace_resolver.go

@@ -278,6 +278,12 @@ func (nsr *NamespaceResolver) ResolveType(n ast.Vertex) {
 	switch nn := n.(type) {
 	case *ast.Nullable:
 		nsr.ResolveType(nn.Expr)
+
+	case *ast.Union:
+		for _, nnn := range nn.Types {
+			nsr.ResolveType(nnn)
+		}
+
 	case *ast.Name:
 		nsr.ResolveName(n, "")
 	case *ast.NameRelative:

pkg/visitor/nsresolver/namespace_resolver_test.go

@@ -540,6 +540,8 @@ func TestResolveFunctionName(t *testing.T) {
 func TestResolveMethodName(t *testing.T) {
 	nameAB := &ast.Name{Parts: []ast.Vertex{&ast.NamePart{Value: []byte("A")}, &ast.NamePart{Value: []byte("B")}}}
 	nameBC := &ast.Name{Parts: []ast.Vertex{&ast.NamePart{Value: []byte("B")}, &ast.NamePart{Value: []byte("C")}}}
+	nameCD := &ast.Name{Parts: []ast.Vertex{&ast.NamePart{Value: []byte("C")}, &ast.NamePart{Value: []byte("D")}}}
+	nameDE := &ast.Name{Parts: []ast.Vertex{&ast.NamePart{Value: []byte("D")}, &ast.NamePart{Value: []byte("E")}}}
 
 	methodNode := &ast.StmtClassMethod{
 		Name: &ast.Identifier{Value: []byte("A")},
@@ -548,6 +550,10 @@ func TestResolveMethodName(t *testing.T) {
 				Type: nameAB,
 				Var:  &ast.ExprVariable{Name: &ast.Identifier{Value: []byte("foo")}},
 			},
+			&ast.Parameter{
+				Type: &ast.Union{Types: []ast.Vertex{nameCD, nameDE}},
+				Var:  &ast.ExprVariable{Name: &ast.Identifier{Value: []byte("all")}},
+			},
 		},
 		ReturnType: &ast.Nullable{Expr: nameBC},
 		Stmt: &ast.StmtStmtList{
@@ -558,6 +564,8 @@ func TestResolveMethodName(t *testing.T) {
 	expected := map[ast.Vertex]string{
 		nameAB: "A\\B",
 		nameBC: "B\\C",
+		nameCD: "C\\D",
+		nameDE: "D\\E",
 	}
 
 	nsResolver := nsresolver.NewNamespaceResolver()