Add NewTestBundle function to testutils package

This commit adds small helper function in testutils module, that would
help with testing modules that relay on bundle interface. The function
will take directory with testdata as a parameter, and load all files in
it into its fakefile system, allowing bundle to get those files and
render required yaml/kustomize files storing them as airship documents
in the returned bundle.

Change-Id: Ib55180cc720c42cab77626601d9ec0d6151b8454

pkg/document/bundle_test.go

@@ -9,18 +9,12 @@ import (
 	"sigs.k8s.io/kustomize/v3/pkg/gvk"
 	"sigs.k8s.io/kustomize/v3/pkg/types"
 
-	"opendev.org/airship/airshipctl/pkg/document"
 	"opendev.org/airship/airshipctl/testutil"
 )
 
 func TestNewBundle(t *testing.T) {
 
-	fSys := testutil.SetupTestFs(t, "testdata")
+	bundle := testutil.NewTestBundle(t, "testdata")
-	bundle, err := document.NewBundle(fSys, "/", "/")
-	if err != nil {
-		t.Fatalf("Building Bundle Failed: %v", err)
-	}
-
 	require := require.New(t)
 	require.NotNil(bundle)
 
@@ -28,12 +22,7 @@ func TestNewBundle(t *testing.T) {
 
 func TestBundleDocumentFiltering(t *testing.T) {
 
-	fSys := testutil.SetupTestFs(t, "testdata")
+	bundle := testutil.NewTestBundle(t, "testdata")
-	bundle, err := document.NewBundle(fSys, "/", "/")
-	if err != nil {
-		t.Fatalf("Building Bundle Failed: %v", err)
-	}
-
 	assert := assert.New(t)
 
 	t.Run("GetKustomizeResourceMap", func(t *testing.T) {

testutil/testdatafs.go

@@ -5,7 +5,10 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/v3/pkg/fs"
+
+	"opendev.org/airship/airshipctl/pkg/document"
 )
 
 // SetupTestFs help manufacture a fake file system for testing purposes. It
@@ -13,26 +16,28 @@ import (
 // to the tests themselves, and will write each of those files (preserving
 // names) to an in-memory file system and return that fs
 func SetupTestFs(t *testing.T, fixtureDir string) fs.FileSystem {
+	t.Helper()
 
 	x := fs.MakeFakeFS()
 
 	files, err := ioutil.ReadDir(fixtureDir)
-	if err != nil {
+	require.NoError(t, err, "Failed to read fixture directory, setting up testfs failed")
-		t.Fatalf("Unable to read fixture directory %s: %v", fixtureDir, err)
-	}
 	for _, file := range files {
 		fileName := file.Name()
 		filePath := filepath.Join(fixtureDir, fileName)
 		fileBytes, err := ioutil.ReadFile(filePath)
-		if err != nil {
+		require.NoError(t, err, "Failed to read file, setting up testfs failed")
-			t.Fatalf("Error reading fixture %s: %v", filePath, err)
-		}
-		// nolint: errcheck
 		err = x.WriteFile(filepath.Join("/", file.Name()), fileBytes)
-		if err != nil {
+		require.NoError(t, err, "Failed to write file, setting up testfs failed")
-			t.Fatalf("Error writing fixture %s: %v", filePath, err)
-		}
 	}
 	return x
 
 }
+
+// NewTestBundle helps to create a new bundle with FakeFs containing documents from fixtureDir
+func NewTestBundle(t *testing.T, fixtureDir string) document.Bundle {
+	t.Helper()
+	b, err := document.NewBundle(SetupTestFs(t, fixtureDir), "/", "/")
+	require.NoError(t, err, "Failed to build a bundle, setting up TestBundle failed")
+	return b
+}