Fix generating into same package

arguments/parser.go

@@ -46,6 +46,12 @@ func New(args []string, workingDir string, evaler Evaler, stater Stater) (*Parse
 		"Display this help",
 	)
 
+	testFlag := fs.Bool(
+		"test",
+		false,
+		"Append \"_test\" to pacakge name",
+	)
+
 	err := fs.Parse(args[1:])
 	if err != nil {
 		return nil, err
@@ -59,9 +65,9 @@ func New(args []string, workingDir string, evaler Evaler, stater Stater) (*Parse
 
 	packageMode := *packageFlag
 	result := &ParsedArguments{
-		PrintToStdOut: any(args, "-"),
+		PrintToStdOut:                                any(args, "-"),
 		GenerateInterfaceAndShimFromPackageDirectory: packageMode,
-		GenerateMode: *generateFlag,
+		GenerateMode:                                 *generateFlag,
 	}
 	if *generateFlag {
 		return result, nil
@@ -75,6 +81,9 @@ func New(args []string, workingDir string, evaler Evaler, stater Stater) (*Parse
 	result.parseOutputPath(packageMode, workingDir, *outputPathFlag, fs.Args())
 	result.parseDestinationPackageName(packageMode, fs.Args())
 	result.parsePackagePath(packageMode, fs.Args())
+	if *testFlag {
+		result.TestPackage = true
+	}
 	return result, nil
 }
 
@@ -154,11 +163,13 @@ func (a *ParsedArguments) parseOutputPath(packageMode bool, workingDir string, o
 
 func (a *ParsedArguments) parseDestinationPackageName(packageMode bool, args []string) {
 	if packageMode {
+		// TODO: a.DestinationPackagePath
 		a.parsePackagePath(packageMode, args)
 		a.DestinationPackageName = path.Base(a.PackagePath) + "shim"
 		return
 	}
 
+	a.DestinationPackagePath = filepath.Dir(a.OutputPath)
 	a.DestinationPackageName = restrictToValidPackageName(filepath.Base(filepath.Dir(a.OutputPath)))
 }
 
@@ -182,11 +193,13 @@ func (a *ParsedArguments) parsePackagePath(packageMode bool, args []string) {
 type ParsedArguments struct {
 	GenerateInterfaceAndShimFromPackageDirectory bool
 
-	SourcePackageDir string // abs path to the dir containing the interface to fake
-	PackagePath      string // package path to the package containing the interface to fake
-	OutputPath       string // path to write the fake file to
+	SourcePackageDir       string // abs path to the dir containing the interface to fake
+	PackagePath            string // package path to the package containing the interface to fake
+	OutputPath             string // path to write the fake file to
+	DestinationPackagePath string // path to destination package
+	TestPackage            bool   // append "_test" to package name
 
-	DestinationPackageName string // often the base-dir for OutputPath but must be a valid package name
+	DestinationPackageName string // often the base-dir for OutputPath but must be a valid package name DEPRECATED
 
 	InterfaceName string // the interface to counterfeit
 	FakeImplName  string // the name of the struct implementing the given interface

arguments/usage.go

@@ -3,7 +3,7 @@ package arguments
 const usage = `
 USAGE
 	counterfeiter
-		[-generate>] [-o <output-path>] [-p] [--fake-name <fake-name>]
+		[-generate>] [-o <output-path>] [-p] [--fake-name <fake-name>] [--test]
 		[<source-path>] <interface> [-]
 
 ARGUMENTS
@@ -83,4 +83,8 @@ OPTIONS
 	example:
 		# writes "CoolThing" to ./mypackagefakes/cool_thing.go
 		counterfeiter --fake-name CoolThing ./mypackage MyInterface
+
+	--test
+		When generating into the same directory as the source interface,
+		append a "_test" suffix to the package name of the generated file.
 `

fixtures/same/interface.go

@@ -0,0 +1,9 @@
+package same // import "github.com/maxbrunsfeld/counterfeiter/v6/fixtures/same"
+
+//go:generate go run github.com/maxbrunsfeld/counterfeiter/v6 -o same_fake.go . SomeInterface
+type SomeInterface interface {
+	DoThings(string, uint64) (int, error)
+	DoNothing()
+	DoASlice([]byte)
+	DoAnArray([4]byte)
+}

fixtures/same/notexported.go

@@ -0,0 +1,9 @@
+package same // import "github.com/maxbrunsfeld/counterfeiter/v6/fixtures/same"
+
+//go:generate go run github.com/maxbrunsfeld/counterfeiter/v6 -o notexported_fake.go . someNotExportedInterface
+type someNotExportedInterface interface {
+	DoThings(string, uint64) (int, error)
+	DoNothing()
+	DoASlice([]byte)
+	DoAnArray([4]byte)
+}