Fix moq for go 1.13 and avoid creating empty directory (#105)

* Fix moq for go 1.13 and avoid creating empty directory

This fixes #103 and also fixes #102

* Update .travis.yml

.travis.yml

@@ -3,9 +3,9 @@ language: go
 sudo: false
 
 go:
-  - 1.9.x
-  - 1.10.x
   - 1.11.x
+  - 1.12.x
+  - 1.13.x
   - tip
 
 before_install:

pkg/moq/moq.go

@@ -73,22 +73,11 @@ type Mocker struct {
 func New(src, packageName string) (*Mocker, error) {
 	srcPkg, err := pkgInfoFromPath(src, packages.LoadSyntax)
 	if err != nil {
-		return nil, fmt.Errorf("Couldn't load source package: %s", err)
+		return nil, fmt.Errorf("couldn't load source package: %s", err)
 	}
-	pkgPath := srcPkg.PkgPath
-
-	if len(packageName) == 0 {
-		packageName = srcPkg.Name
-	} else {
-		mockPkgPath := filepath.Join(src, packageName)
-		if _, err := os.Stat(mockPkgPath); os.IsNotExist(err) {
-			os.Mkdir(mockPkgPath, os.ModePerm)
-		}
-		mockPkg, err := pkgInfoFromPath(mockPkgPath, packages.LoadFiles)
+	pkgPath, err := findPkgPath(packageName, srcPkg)
 	if err != nil {
-			return nil, fmt.Errorf("Couldn't load mock package: %s", err)
-		}
-		pkgPath = mockPkg.PkgPath
+		return nil, fmt.Errorf("couldn't load mock package: %s", err)
 	}
 
 	tmpl, err := template.New("moq").Funcs(templateFuncs).Parse(moqTemplate)
@@ -98,12 +87,44 @@ func New(src, packageName string) (*Mocker, error) {
 	return &Mocker{
 		tmpl:    tmpl,
 		srcPkg:  srcPkg,
-		pkgName: packageName,
+		pkgName: preventZeroStr(packageName, srcPkg.Name),
 		pkgPath: pkgPath,
 		imports: make(map[string]bool),
 	}, nil
 }
 
+func preventZeroStr(val, defaultVal string) string {
+	if val == "" {
+		return defaultVal
+	}
+	return val
+}
+
+func findPkgPath(pkgInputVal string, srcPkg *packages.Package) (string, error) {
+	if pkgInputVal == "" {
+		return srcPkg.PkgPath, nil
+	}
+	if pkgInDir(".", pkgInputVal) {
+		return ".", nil
+	}
+	if pkgInDir(srcPkg.PkgPath, pkgInputVal) {
+		return srcPkg.PkgPath, nil
+	}
+	subdirectoryPath := filepath.Join(srcPkg.PkgPath, pkgInputVal)
+	if pkgInDir(subdirectoryPath, pkgInputVal) {
+		return subdirectoryPath, nil
+	}
+	return "", nil
+}
+
+func pkgInDir(pkgName, dir string) bool {
+	currentPkg, err := pkgInfoFromPath(dir, packages.LoadFiles)
+	if err != nil {
+		return false
+	}
+	return currentPkg.Name == pkgName || currentPkg.Name+"_test" == pkgName
+}
+
 // Mock generates a mock for the specified interface name.
 func (m *Mocker) Mock(w io.Writer, name ...string) error {
 	if len(name) == 0 {
@@ -173,7 +194,7 @@ func (m *Mocker) Mock(w io.Writer, name ...string) error {
 }
 
 func (m *Mocker) packageQualifier(pkg *types.Package) string {
-	if m.pkgPath == pkg.Path() {
+	if m.pkgPath != "" && m.pkgPath == pkg.Path() {
 		return ""
 	}
 	path := pkg.Path()

pkg/moq/moq_test.go

@@ -131,6 +131,25 @@ func TestMoqExplicitPackageWithStaticCheck(t *testing.T) {
 	}
 }
 
+func TestNotCreatingEmptyDirWhenPkgIsGiven(t *testing.T) {
+	m, err := New("testpackages/example", "different")
+	if err != nil {
+		t.Fatalf("moq.New: %s", err)
+	}
+	var buf bytes.Buffer
+	err = m.Mock(&buf, "PersonStore")
+	if err != nil {
+		t.Errorf("m.Mock: %s", err)
+	}
+	s := buf.String()
+	if len(s) == 0 {
+		t.Fatalf("mock should be generated")
+	}
+	if _, err := os.Stat("testpackages/example/different"); !os.IsNotExist(err) {
+		t.Fatalf("no empty dir should be created by moq")
+	}
+}
+
 // TestVeradicArguments tests to ensure variadic work as
 // expected.
 // see https://github.com/matryer/moq/issues/5