chore: interface{} -> any

README.md

@@ -648,7 +648,7 @@ normal validation.
 
 ## Modifying Kong's behaviour
 
-Each Kong parser can be configured via functional options passed to `New(cli interface{}, options...Option)`.
+Each Kong parser can be configured via functional options passed to `New(cli any, options...Option)`.
 
 The full set of options can be found [here](https://godoc.org/github.com/alecthomas/kong#Option).
 
@@ -706,7 +706,7 @@ All builtin Go types (as well as a bunch of useful stdlib types like `time.Time`
 1. `NamedMapper(string, Mapper)` and using the tag key `type:"<name>"`.
 2. `KindMapper(reflect.Kind, Mapper)`.
 3. `TypeMapper(reflect.Type, Mapper)`.
-4. `ValueMapper(interface{}, Mapper)`, passing in a pointer to a field of the grammar.
+4. `ValueMapper(any, Mapper)`, passing in a pointer to a field of the grammar.
 
 ### `ConfigureHelp(HelpOptions)` and `Help(HelpFunc)` - customising help
 

build.go

@@ -9,9 +9,9 @@ import (
 // Plugins are dynamically embedded command-line structures.
 //
 // Each element in the Plugins list *must* be a pointer to a structure.
-type Plugins []interface{}
+type Plugins []any
 
-func build(k *Kong, ast interface{}) (app *Application, err error) {
+func build(k *Kong, ast any) (app *Application, err error) {
 	v := reflect.ValueOf(ast)
 	iv := reflect.Indirect(v)
 	if v.Kind() != reflect.Ptr || iv.Kind() != reflect.Struct {

callbacks.go

@@ -19,7 +19,7 @@ func (b bindings) String() string {
 	return "bindings{" + strings.Join(out, ", ") + "}"
 }
 
-func (b bindings) add(values ...interface{}) bindings {
+func (b bindings) add(values ...any) bindings {
 	for _, v := range values {
 		v := v
 		b[reflect.TypeOf(v)] = func() (any, error) { return v, nil }
@@ -27,11 +27,11 @@ func (b bindings) add(values ...interface{}) bindings {
 	return b
 }
 
-func (b bindings) addTo(impl, iface interface{}) {
+func (b bindings) addTo(impl, iface any) {
 	b[reflect.TypeOf(iface).Elem()] = func() (any, error) { return impl, nil }
 }
 
-func (b bindings) addProvider(provider interface{}) error {
+func (b bindings) addProvider(provider any) error {
 	pv := reflect.ValueOf(provider)
 	t := pv.Type()
 	if t.Kind() != reflect.Func || t.NumOut() != 2 || t.Out(1) != reflect.TypeOf((*error)(nil)).Elem() {

config_test.go

@@ -42,7 +42,7 @@ func TestConfigValidation(t *testing.T) {
 	assert.Error(t, err)
 }
 
-func makeConfig(t *testing.T, config interface{}) (path string, cleanup func()) {
+func makeConfig(t *testing.T, config any) (path string, cleanup func()) {
 	t.Helper()
 	w, err := os.CreateTemp("", "")
 	assert.NoError(t, err)

context.go

@@ -102,7 +102,7 @@ func Trace(k *Kong, args []string) (*Context, error) {
 }
 
 // Bind adds bindings to the Context.
-func (c *Context) Bind(args ...interface{}) {
+func (c *Context) Bind(args ...any) {
 	c.bindings.add(args...)
 }
 
@@ -111,7 +111,7 @@ func (c *Context) Bind(args ...interface{}) {
 // This will typically have to be called like so:
 //
 //	BindTo(impl, (*MyInterface)(nil))
-func (c *Context) BindTo(impl, iface interface{}) {
+func (c *Context) BindTo(impl, iface any) {
 	c.bindings.addTo(impl, iface)
 }
 
@@ -119,7 +119,7 @@ func (c *Context) BindTo(impl, iface interface{}) {
 //
 // This is useful when the Run() function of different commands require different values that may
 // not all be initialisable from the main() function.
-func (c *Context) BindToProvider(provider interface{}) error {
+func (c *Context) BindToProvider(provider any) error {
 	return c.bindings.addProvider(provider)
 }
 
@@ -306,7 +306,7 @@ func (c *Context) AddResolver(resolver Resolver) {
 }
 
 // FlagValue returns the set value of a flag if it was encountered and exists, or its default value.
-func (c *Context) FlagValue(flag *Flag) interface{} {
+func (c *Context) FlagValue(flag *Flag) any {
 	for _, trace := range c.Path {
 		if trace.Flag == flag {
 			v, ok := c.values[trace.Flag.Value]
@@ -572,7 +572,7 @@ func (c *Context) Resolve() error {
 			}
 
 			// Pick the last resolved value.
-			var selected interface{}
+			var selected any
 			for _, resolver := range resolvers {
 				s, err := resolver.Resolve(c, path, flag)
 				if err != nil {
@@ -757,7 +757,7 @@ func (e *unknownFlagError) Unwrap() error { return e.Cause }
 func (e *unknownFlagError) Error() string { return e.Cause.Error() }
 
 // Call an arbitrary function filling arguments with bound values.
-func (c *Context) Call(fn any, binds ...interface{}) (out []interface{}, err error) {
+func (c *Context) Call(fn any, binds ...any) (out []any, err error) {
 	fv := reflect.ValueOf(fn)
 	bindings := c.Kong.bindings.clone().add(binds...).add(c).merge(c.bindings)
 	return callAnyFunction(fv, bindings)
@@ -769,7 +769,7 @@ func (c *Context) Call(fn any, binds ...interface{}) (out []interface{}, err err
 //
 // Any passed values will be bindable to arguments of the target Run() method. Additionally,
 // all parent nodes in the command structure will be bound.
-func (c *Context) RunNode(node *Node, binds ...interface{}) (err error) {
+func (c *Context) RunNode(node *Node, binds ...any) (err error) {
 	type targetMethod struct {
 		node   *Node
 		method reflect.Value
@@ -815,7 +815,7 @@ func (c *Context) RunNode(node *Node, binds ...interface{}) (err error) {
 //
 // Any passed values will be bindable to arguments of the target Run() method. Additionally,
 // all parent nodes in the command structure will be bound.
-func (c *Context) Run(binds ...interface{}) (err error) {
+func (c *Context) Run(binds ...any) (err error) {
 	node := c.Selected()
 	if node == nil {
 		if len(c.Path) == 0 {
@@ -1087,7 +1087,7 @@ func checkAndMissing(paths []*Path) error {
 	return nil
 }
 
-func findPotentialCandidates(needle string, haystack []string, format string, args ...interface{}) error {
+func findPotentialCandidates(needle string, haystack []string, format string, args ...any) error {
 	if len(haystack) == 0 {
 		return fmt.Errorf(format, args...)
 	}

defaults.go

@@ -1,7 +1,7 @@
 package kong
 
 // ApplyDefaults if they are not already set.
-func ApplyDefaults(target interface{}, options ...Option) error {
+func ApplyDefaults(target any, options ...Option) error {
 	app, err := New(target, options...)
 	if err != nil {
 		return err

global.go

@@ -5,7 +5,7 @@ import (
 )
 
 // Parse constructs a new parser and parses the default command-line.
-func Parse(cli interface{}, options ...Option) *Context {
+func Parse(cli any, options ...Option) *Context {
 	parser, err := New(cli, options...)
 	if err != nil {
 		panic(err)

help.go

@@ -386,7 +386,7 @@ func newHelpWriter(ctx *Context, options HelpOptions) *helpWriter {
 	return w
 }
 
-func (h *helpWriter) Printf(format string, args ...interface{}) {
+func (h *helpWriter) Printf(format string, args ...any) {
 	h.Print(fmt.Sprintf(format, args...))
 }
 

kong.go

@@ -15,7 +15,7 @@ var (
 	callbackReturnSignature = reflect.TypeOf((*error)(nil)).Elem()
 )
 
-func failField(parent reflect.Value, field reflect.StructField, format string, args ...interface{}) error {
+func failField(parent reflect.Value, field reflect.StructField, format string, args ...any) error {
 	name := parent.Type().Name()
 	if name == "" {
 		name = "<anonymous struct>"
@@ -24,7 +24,7 @@ func failField(parent reflect.Value, field reflect.StructField, format string, a
 }
 
 // Must creates a new Parser or panics if there is an error.
-func Must(ast interface{}, options ...Option) *Kong {
+func Must(ast any, options ...Option) *Kong {
 	k, err := New(ast, options...)
 	if err != nil {
 		panic(err)
@@ -76,7 +76,7 @@ type Kong struct {
 // New creates a new Kong parser on grammar.
 //
 // See the README (https://github.com/alecthomas/kong) for usage instructions.
-func New(grammar interface{}, options ...Option) (*Kong, error) {
+func New(grammar any, options ...Option) (*Kong, error) {
 	k := &Kong{
 		Exit:          os.Exit,
 		Stdout:        os.Stdout,
@@ -401,7 +401,7 @@ func (k *Kong) applyHookToDefaultFlags(ctx *Context, node *Node, name string) er
 	})
 }
 
-func formatMultilineMessage(w io.Writer, leaders []string, format string, args ...interface{}) {
+func formatMultilineMessage(w io.Writer, leaders []string, format string, args ...any) {
 	lines := strings.Split(strings.TrimRight(fmt.Sprintf(format, args...), "\n"), "\n")
 	leader := ""
 	for _, l := range leaders {
@@ -417,25 +417,25 @@ func formatMultilineMessage(w io.Writer, leaders []string, format string, args .
 }
 
 // Printf writes a message to Kong.Stdout with the application name prefixed.
-func (k *Kong) Printf(format string, args ...interface{}) *Kong {
+func (k *Kong) Printf(format string, args ...any) *Kong {
 	formatMultilineMessage(k.Stdout, []string{k.Model.Name}, format, args...)
 	return k
 }
 
 // Errorf writes a message to Kong.Stderr with the application name prefixed.
-func (k *Kong) Errorf(format string, args ...interface{}) *Kong {
+func (k *Kong) Errorf(format string, args ...any) *Kong {
 	formatMultilineMessage(k.Stderr, []string{k.Model.Name, "error"}, format, args...)
 	return k
 }
 
 // Fatalf writes a message to Kong.Stderr with the application name prefixed then exits with a non-zero status.
-func (k *Kong) Fatalf(format string, args ...interface{}) {
+func (k *Kong) Fatalf(format string, args ...any) {
 	k.Errorf(format, args...)
 	k.Exit(1)
 }
 
 // FatalIfErrorf terminates with an error message if err != nil.
-func (k *Kong) FatalIfErrorf(err error, args ...interface{}) {
+func (k *Kong) FatalIfErrorf(err error, args ...any) {
 	if err == nil {
 		return
 	}

kong_test.go

@@ -14,7 +14,7 @@ import (
 	"github.com/alecthomas/kong"
 )
 
-func mustNew(t *testing.T, cli interface{}, options ...kong.Option) *kong.Kong {
+func mustNew(t *testing.T, cli any, options ...kong.Option) *kong.Kong {
 	t.Helper()
 	options = append([]kong.Option{
 		kong.Name("test"),
@@ -1680,7 +1680,7 @@ func TestOptionReturnsErr(t *testing.T) {
 func TestEnumValidation(t *testing.T) {
 	tests := []struct {
 		name string
-		cli  interface{}
+		cli  any
 		fail bool
 	}{
 		{
@@ -1954,7 +1954,7 @@ func TestVersionFlagShouldStillWork(t *testing.T) {
 func TestSliceDecoderHelpfulErrorMsg(t *testing.T) {
 	tests := []struct {
 		name string
-		cli  interface{}
+		cli  any
 		args []string
 		err  string
 	}{
@@ -2004,7 +2004,7 @@ func TestSliceDecoderHelpfulErrorMsg(t *testing.T) {
 func TestMapDecoderHelpfulErrorMsg(t *testing.T) {
 	tests := []struct {
 		name     string
-		cli      interface{}
+		cli      any
 		args     []string
 		expected string
 	}{

mapper.go

@@ -251,7 +251,7 @@ func (r *Registry) RegisterType(typ reflect.Type, mapper Mapper) *Registry {
 }
 
 // RegisterValue registers a Mapper by pointer to the field value.
-func (r *Registry) RegisterValue(ptr interface{}, mapper Mapper) *Registry {
+func (r *Registry) RegisterValue(ptr any, mapper Mapper) *Registry {
 	key := reflect.ValueOf(ptr)
 	if key.Kind() != reflect.Ptr {
 		panic("expected a pointer")
@@ -473,7 +473,7 @@ func mapDecoder(r *Registry) MapperFunc {
 			case string:
 				childScanner = ScanAsType(t.Type, SplitEscaped(v, mapsep)...)
 
-			case []map[string]interface{}:
+			case []map[string]any:
 				for _, m := range v {
 					err := jsonTranscode(m, target.Addr().Interface())
 					if err != nil {
@@ -482,7 +482,7 @@ func mapDecoder(r *Registry) MapperFunc {
 				}
 				return nil
 
-			case map[string]interface{}:
+			case map[string]any:
 				return jsonTranscode(v, target.Addr().Interface())
 
 			default:
@@ -548,11 +548,11 @@ func sliceDecoder(r *Registry) MapperFunc {
 			case string:
 				childScanner = ScanAsType(t.Type, SplitEscaped(v, sep)...)
 
-			case []interface{}:
+			case []any:
 				return jsonTranscode(v, target.Addr().Interface())
 
 			default:
-				v = []interface{}{v}
+				v = []any{v}
 				return jsonTranscode(v, target.Addr().Interface())
 			}
 		} else {
@@ -922,7 +922,7 @@ func (f *FileContentFlag) Decode(ctx *DecodeContext) error { //nolint: revive
 	return nil
 }
 
-func jsonTranscode(in, out interface{}) error {
+func jsonTranscode(in, out any) error {
 	data, err := json.Marshal(in)
 	if err != nil {
 		return err

model.go

@@ -69,7 +69,7 @@ func (n *Node) Leaf() bool {
 // Find a command/argument/flag by pointer to its field.
 //
 // Returns nil if not found. Panics if ptr is not a pointer.
-func (n *Node) Find(ptr interface{}) *Node {
+func (n *Node) Find(ptr any) *Node {
 	key := reflect.ValueOf(ptr)
 	if key.Kind() != reflect.Ptr {
 		panic("expected a pointer")

options.go

@@ -79,7 +79,7 @@ type dynamicCommand struct {
 	help  string
 	group string
 	tags  []string
-	cmd   interface{}
+	cmd   any
 }
 
 // DynamicCommand registers a dynamically constructed command with the root of the CLI.
@@ -87,7 +87,7 @@ type dynamicCommand struct {
 // This is useful for command-line structures that are extensible via user-provided plugins.
 //
 // "tags" is a list of extra tag strings to parse, in the form <key>:"<value>".
-func DynamicCommand(name, help, group string, cmd interface{}, tags ...string) Option {
+func DynamicCommand(name, help, group string, cmd any, tags ...string) Option {
 	return OptionFunc(func(k *Kong) error {
 		if run := getMethod(reflect.Indirect(reflect.ValueOf(cmd)), "Run"); !run.IsValid() {
 			return fmt.Errorf("kong: DynamicCommand %q must be a type with a 'Run' method; got %T", name, cmd)
@@ -156,7 +156,7 @@ func KindMapper(kind reflect.Kind, mapper Mapper) Option {
 }
 
 // ValueMapper registers a mapper to a field value.
-func ValueMapper(ptr interface{}, mapper Mapper) Option {
+func ValueMapper(ptr any, mapper Mapper) Option {
 	return OptionFunc(func(k *Kong) error {
 		k.registry.RegisterValue(ptr, mapper)
 		return nil
@@ -191,7 +191,7 @@ func Writers(stdout, stderr io.Writer) Option {
 //	  	AfterApply(...) error
 //
 // Called before validation/assignment, and immediately after validation/assignment, respectively.
-func Bind(args ...interface{}) Option {
+func Bind(args ...any) Option {
 	return OptionFunc(func(k *Kong) error {
 		k.bindings.add(args...)
 		return nil
@@ -201,7 +201,7 @@ func Bind(args ...interface{}) Option {
 // BindTo allows binding of implementations to interfaces.
 //
 //	BindTo(impl, (*iface)(nil))
-func BindTo(impl, iface interface{}) Option {
+func BindTo(impl, iface any) Option {
 	return OptionFunc(func(k *Kong) error {
 		k.bindings.addTo(impl, iface)
 		return nil
@@ -212,11 +212,11 @@ func BindTo(impl, iface interface{}) Option {
 //
 // The provider function must have the signature:
 //
-//	func() (interface{}, error)
+//	func() (any, error)
 //
 // This is useful when the Run() function of different commands require different values that may
 // not all be initialisable from the main() function.
-func BindToProvider(provider interface{}) Option {
+func BindToProvider(provider any) Option {
 	return OptionFunc(func(k *Kong) error {
 		return k.bindings.addProvider(provider)
 	})

resolver.go

@@ -14,15 +14,15 @@ type Resolver interface {
 	Validate(app *Application) error
 
 	// Resolve the value for a Flag.
-	Resolve(context *Context, parent *Path, flag *Flag) (interface{}, error)
+	Resolve(context *Context, parent *Path, flag *Flag) (any, error)
 }
 
 // ResolverFunc is a convenience type for non-validating Resolvers.
-type ResolverFunc func(context *Context, parent *Path, flag *Flag) (interface{}, error)
+type ResolverFunc func(context *Context, parent *Path, flag *Flag) (any, error)
 
 var _ Resolver = ResolverFunc(nil)
 
-func (r ResolverFunc) Resolve(context *Context, parent *Path, flag *Flag) (interface{}, error) { //nolint: revive
+func (r ResolverFunc) Resolve(context *Context, parent *Path, flag *Flag) (any, error) { //nolint: revive
 	return r(context, parent, flag)
 }
 func (r ResolverFunc) Validate(app *Application) error { return nil } //nolint: revive
@@ -31,12 +31,12 @@ func (r ResolverFunc) Validate(app *Application) error { return nil } //nolint:
 //
 // Flag names are used as JSON keys indirectly, by tring snake_case and camelCase variants.
 func JSON(r io.Reader) (Resolver, error) {
-	values := map[string]interface{}{}
+	values := map[string]any{}
 	err := json.NewDecoder(r).Decode(&values)
 	if err != nil {
 		return nil, err
 	}
-	var f ResolverFunc = func(context *Context, parent *Path, flag *Flag) (interface{}, error) {
+	var f ResolverFunc = func(context *Context, parent *Path, flag *Flag) (any, error) {
 		name := strings.ReplaceAll(flag.Name, "-", "_")
 		snakeCaseName := snakeCase(flag.Name)
 		raw, ok := values[name]
@@ -47,7 +47,7 @@ func JSON(r io.Reader) (Resolver, error) {
 		}
 		raw = values
 		for _, part := range strings.Split(name, ".") {
-			if values, ok := raw.(map[string]interface{}); ok {
+			if values, ok := raw.(map[string]any); ok {
 				raw, ok = values[part]
 				if !ok {
 					return nil, nil

resolver_test.go

@@ -12,7 +12,7 @@ import (
 
 type envMap map[string]string
 
-func newEnvParser(t *testing.T, cli interface{}, env envMap, options ...kong.Option) *kong.Kong {
+func newEnvParser(t *testing.T, cli any, env envMap, options ...kong.Option) *kong.Kong {
 	t.Helper()
 	for name, value := range env {
 		t.Setenv(name, value)
@@ -275,7 +275,7 @@ func TestResolverWithBool(t *testing.T) {
 		Bool bool
 	}
 
-	var resolver kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+	var resolver kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 		if flag.Name == "bool" {
 			return true, nil
 		}
@@ -294,14 +294,14 @@ func TestLastResolverWins(t *testing.T) {
 		Int []int
 	}
 
-	var first kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+	var first kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 		if flag.Name == "int" {
 			return 1, nil
 		}
 		return nil, nil
 	}
 
-	var second kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+	var second kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 		if flag.Name == "int" {
 			return 2, nil
 		}
@@ -318,7 +318,7 @@ func TestResolverSatisfiesRequired(t *testing.T) {
 	var cli struct {
 		Int int `required`
 	}
-	var resolver kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+	var resolver kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 		if flag.Name == "int" {
 			return 1, nil
 		}
@@ -336,7 +336,7 @@ func TestResolverTriggersHooks(t *testing.T) {
 		Flag hookValue
 	}
 
-	var first kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+	var first kong.ResolverFunc = func(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 		if flag.Name == "flag" {
 			return "one", nil
 		}
@@ -355,7 +355,7 @@ type validatingResolver struct {
 }
 
 func (v *validatingResolver) Validate(app *kong.Application) error { return v.err }
-func (v *validatingResolver) Resolve(context *kong.Context, parent *kong.Path, flag *kong.Flag) (interface{}, error) {
+func (v *validatingResolver) Resolve(context *kong.Context, parent *kong.Path, flag *kong.Flag) (any, error) {
 	return nil, nil
 }
 

scanner.go

@@ -41,7 +41,7 @@ func (t TokenType) String() string {
 
 // Token created by Scanner.
 type Token struct {
-	Value interface{}
+	Value any
 	Type  TokenType
 }
 
@@ -171,7 +171,7 @@ func (s *Scanner) PopValue(context string) (Token, error) {
 // PopValueInto pops a value token into target or returns an error.
 //
 // "context" is used to assist the user if the value can not be popped, eg. "expected <context> value but got <type>"
-func (s *Scanner) PopValueInto(context string, target interface{}) error {
+func (s *Scanner) PopValueInto(context string, target any) error {
 	t, err := s.PopValue(context)
 	if err != nil {
 		return err
@@ -204,13 +204,13 @@ func (s *Scanner) Peek() Token {
 }
 
 // Push an untyped Token onto the front of the Scanner.
-func (s *Scanner) Push(arg interface{}) *Scanner {
+func (s *Scanner) Push(arg any) *Scanner {
 	s.PushToken(Token{Value: arg})
 	return s
 }
 
 // PushTyped pushes a typed token onto the front of the Scanner.
-func (s *Scanner) PushTyped(arg interface{}, typ TokenType) *Scanner {
+func (s *Scanner) PushTyped(arg any, typ TokenType) *Scanner {
 	s.PushToken(Token{Value: arg, Type: typ})
 	return s
 }