Make new nesting place for generated builtin code.

api/plugins/builtinconfig/loaddefaultconfig_test.go

@@ -0,0 +1,37 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package builtinconfig
+
+import (
+	"reflect"
+	"testing"
+
+	"sigs.k8s.io/kustomize/v3/api/internal/loadertest"
+	"sigs.k8s.io/kustomize/v3/api/resid"
+	"sigs.k8s.io/kustomize/v3/api/types"
+)
+
+func TestLoadDefaultConfigsFromFiles(t *testing.T) {
+	ldr := loadertest.NewFakeLoader("/app")
+	ldr.AddFile("/app/config.yaml", []byte(`
+namePrefix:
+- path: nameprefix/path
+  kind: SomeKind
+`))
+	tcfg, err := loadDefaultConfig(ldr, []string{"/app/config.yaml"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	expected := &TransformerConfig{
+		NamePrefix: []types.FieldSpec{
+			{
+				Gvk:  resid.Gvk{Kind: "SomeKind"},
+				Path: "nameprefix/path",
+			},
+		},
+	}
+	if !reflect.DeepEqual(tcfg, expected) {
+		t.Fatalf("expected %v\n but go6t %v\n", expected, tcfg)
+	}
+}