Add compiler utils test.

api/internal/plugins/compiler/utils_test.go

@@ -0,0 +1,26 @@
+// Copyright 2020 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package compiler
+
+import (
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"sigs.k8s.io/kustomize/api/filesys"
+)
+
+func TestDeterminePluginSrcRoot(t *testing.T) {
+	actual, err := DeterminePluginSrcRoot(filesys.MakeFsOnDisk())
+	if err != nil {
+		t.Error(err)
+	}
+	if !filepath.IsAbs(actual) {
+		t.Errorf("expected absolute path, but got '%s'", actual)
+	}
+	expectedSuffix := filepath.Join("sigs.k8s.io", "kustomize", "plugin")
+	if !strings.HasSuffix(actual, expectedSuffix) {
+		t.Errorf("expected suffix '%s' in '%s'", expectedSuffix, actual)
+	}
+}