Add test case for skaffold init walk

In this change:
1. Refactor walk into its own function
2. Add sample directory structure and tests.

pkg/skaffold/initializer/init.go

@@ -77,35 +77,7 @@ func DoInit(out io.Writer, c Config) error {
 		}
 	}
 
-	var potentialConfigs, dockerfiles []string
-
-	err := filepath.Walk(rootDir, func(path string, f os.FileInfo, e error) error {
-		if f.IsDir() && util.IsHiddenDir(f.Name()) {
-			logrus.Debugf("skip walking hidden dir %s", f.Name())
-			return filepath.SkipDir
-		}
-		if f.IsDir() || util.IsHiddenFile(f.Name()) {
-			return nil
-		}
-		if IsSkaffoldConfig(path) {
-			if !c.Force {
-				return fmt.Errorf("pre-existing %s found", path)
-			}
-			logrus.Debugf("%s is a valid skaffold configuration: continuing since --force=true", path)
-			return nil
-		}
-		if IsSupportedKubernetesFileExtension(path) {
-			potentialConfigs = append(potentialConfigs, path)
-			return nil
-		}
-		// try and parse dockerfile
-		if docker.ValidateDockerfile(path) {
-			logrus.Infof("existing dockerfile found: %s", path)
-			dockerfiles = append(dockerfiles, path)
-		}
-		return nil
-	})
-
+	potentialConfigs, dockerfiles, err := walk(rootDir, c.Force, docker.ValidateDockerfile)
 	if err != nil {
 		return err
 	}
@@ -309,3 +281,37 @@ type dockerfilePair struct {
 	Dockerfile string
 	ImageName  string
 }
+
+func walk(dir string, force bool, validateDockerfile func(string) bool) ([]string, []string, error) {
+	var dockerfiles, potentialConfigs []string
+	err := filepath.Walk(dir, func(path string, f os.FileInfo, e error) error {
+		if f.IsDir() && util.IsHiddenDir(f.Name()) {
+			logrus.Debugf("skip walking hidden dir %s", f.Name())
+			return filepath.SkipDir
+		}
+		if f.IsDir() || util.IsHiddenFile(f.Name()) {
+			return nil
+		}
+		if IsSkaffoldConfig(path) {
+			if !force {
+				return fmt.Errorf("pre-existing %s found", path)
+			}
+			logrus.Debugf("%s is a valid skaffold configuration: continuing since --force=true", path)
+			return nil
+		}
+		if IsSupportedKubernetesFileExtension(path) {
+			potentialConfigs = append(potentialConfigs, path)
+			return nil
+		}
+		// try and parse dockerfile
+		if validateDockerfile(path) {
+			logrus.Infof("existing dockerfile found: %s", path)
+			dockerfiles = append(dockerfiles, path)
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, nil, err
+	}
+	return potentialConfigs, dockerfiles, nil
+}

pkg/skaffold/initializer/init_test.go

@@ -18,6 +18,10 @@ package initializer
 
 import (
 	"bytes"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/GoogleContainerTools/skaffold/testutil"
@@ -59,3 +63,146 @@ func TestPrintAnalyzeJSON(t *testing.T) {
 		})
 	}
 }
+
+func TestWalk(t *testing.T) {
+	emptyFile := []byte("")
+	tests := []struct {
+		name                string
+		filesWithContents   map[string][]byte
+		expectedConfigs     []string
+		expectedDockerfiles []string
+		force               bool
+		err                 bool
+	}{
+		{
+			name: "shd return correct k8 configs and dockerfiles",
+			filesWithContents: map[string][]byte{
+				"config/test.yaml":  emptyFile,
+				"k8pod.yml":         emptyFile,
+				"README":            emptyFile,
+				"deploy/Dockerfile": emptyFile,
+				"Dockerfile":        emptyFile,
+			},
+			force: false,
+			expectedConfigs: []string{
+				"config/test.yaml",
+				"k8pod.yml",
+			},
+			expectedDockerfiles: []string{
+				"Dockerfile",
+				"deploy/Dockerfile",
+			},
+			err: false,
+		},
+		{
+			name: "shd skip hidden dir",
+			filesWithContents: map[string][]byte{
+				".hidden/test.yaml":  emptyFile,
+				"k8pod.yml":          emptyFile,
+				"README":             emptyFile,
+				".hidden/Dockerfile": emptyFile,
+				"Dockerfile":         emptyFile,
+			},
+			force: false,
+			expectedConfigs: []string{
+				"k8pod.yml",
+			},
+			expectedDockerfiles: []string{
+				"Dockerfile",
+			},
+			err: false,
+		},
+		{
+			name: "shd not error when skaffold.config present and force = true",
+			filesWithContents: map[string][]byte{
+				"skaffold.yaml": []byte(`apiVersion: skaffold/v1beta6
+kind: Config
+deploy:
+  kustomize: {}`),
+				"config/test.yaml":  emptyFile,
+				"k8pod.yml":         emptyFile,
+				"README":            emptyFile,
+				"deploy/Dockerfile": emptyFile,
+				"Dockerfile":        emptyFile,
+			},
+			force: true,
+			expectedConfigs: []string{
+				"config/test.yaml",
+				"k8pod.yml",
+			},
+			expectedDockerfiles: []string{
+				"Dockerfile",
+				"deploy/Dockerfile",
+			},
+			err: false,
+		},
+		{
+			name: "shd  error when skaffold.config present and force = false",
+			filesWithContents: map[string][]byte{
+				"config/test.yaml":  emptyFile,
+				"k8pod.yml":         emptyFile,
+				"README":            emptyFile,
+				"deploy/Dockerfile": emptyFile,
+				"Dockerfile":        emptyFile,
+				"skaffold.yaml": []byte(`apiVersion: skaffold/v1beta6
+kind: Config
+deploy:
+  kustomize: {}`),
+			},
+			force:               false,
+			expectedConfigs:     nil,
+			expectedDockerfiles: nil,
+			err:                 true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			rootDir, err := ioutil.TempDir("", "test")
+			if err != nil {
+				t.Fatal(err)
+			}
+			createDirStructure(t, rootDir, test.filesWithContents)
+			potentialConfigs, dockerfiles, err := walk(rootDir, test.force, testValidDocker)
+			testutil.CheckErrorAndDeepEqual(t, test.err, err,
+				convertToAbsPath(rootDir, test.expectedConfigs), potentialConfigs)
+			testutil.CheckErrorAndDeepEqual(t, test.err, err,
+				convertToAbsPath(rootDir, test.expectedDockerfiles), dockerfiles)
+			os.Remove(rootDir)
+		})
+	}
+}
+
+func testValidDocker(path string) bool {
+	return strings.HasSuffix(path, "Dockerfile")
+}
+
+func createDirStructure(t *testing.T, dir string, filesWithContents map[string][]byte) {
+	t.Helper()
+	for file, content := range filesWithContents {
+		// Create Directory path if it does not exist.
+		absPath := filepath.Join(dir, filepath.Dir(file))
+		if _, err := os.Stat(absPath); err != nil {
+			if err := os.MkdirAll(absPath, os.ModePerm); err != nil {
+				t.Fatal(err)
+			}
+		}
+		// Create filepath with contents
+		f, err := os.Create(filepath.Join(dir, file))
+		if err != nil {
+			t.Fatal(err)
+		}
+		f.Write(content)
+		f.Close()
+	}
+}
+
+func convertToAbsPath(dir string, files []string) []string {
+	if files == nil {
+		return files
+	}
+	absPaths := make([]string, len(files))
+	for i, file := range files {
+		absPaths[i] = filepath.Join(dir, file)
+	}
+	return absPaths
+}