Rename Value.Value to Value.Target to correctly reflect its purpose.

build.go

@@ -131,7 +131,7 @@ func buildField(k *Kong, node *Node, v reflect.Value, ft reflect.StructField, fv
 		Default: tag.Default,
 		Mapper:  mapper,
 		Tag:     tag,
-		Value:   fv,
+		Target:  fv,
 
 		// Flags are optional by default, and args are required by default.
 		Required: (!tag.Arg && tag.Required) || (tag.Arg && !tag.Optional),

help.go

@@ -197,7 +197,7 @@ func formatFlag(haveShort bool, flag *Flag) string {
 	if !isBool {
 		flagString += fmt.Sprintf("=%s", flag.FormatPlaceHolder())
 	}
-	if flag.Value.Value.Kind() == reflect.Slice {
+	if flag.Value.Target.Kind() == reflect.Slice {
 		flagString += " ..."
 	}
 	return flagString

kong.go

@@ -90,7 +90,7 @@ func (k *Kong) extraFlags() []*Flag {
 		Value: &Value{
 			Name:   "help",
 			Help:   "Show context-sensitive help.",
-			Value:  value,
+			Target: value,
 			Tag:    &Tag{},
 			Mapper: k.registry.ForValue(value),
 		},
@@ -152,9 +152,9 @@ func (k *Kong) applyHooks(ctx *Context) error {
 		case trace.Command != nil:
 			key = trace.Command.Target
 		case trace.Positional != nil:
-			key = trace.Positional.Value
+			key = trace.Positional.Target
 		case trace.Flag != nil:
-			key = trace.Flag.Value.Value
+			key = trace.Flag.Value.Target
 		default:
 			panic("unsupported Path")
 		}

kong_test.go

@@ -391,12 +391,13 @@ func TestDuplicateFlagChoosesLast(t *testing.T) {
 	require.Equal(t, 2, cli.Flag)
 }
 
-func TestDuplicateSliceDoesNotAccumulate(t *testing.T) {
+func TestDuplicateSliceAccumulates(t *testing.T) {
 	var cli struct {
 		Flag []int
 	}
 
-	_, err := mustNew(t, &cli).Parse([]string{"--flag=1,2", "--flag=3,4"})
+	args := []string{"--flag=1,2", "--flag=3,4"}
+	_, err := mustNew(t, &cli).Parse(args)
 	require.NoError(t, err)
-	require.Equal(t, []int{3, 4}, cli.Flag)
+	require.Equal(t, []int{1, 2, 3, 4}, cli.Flag)
 }

mapper.go

@@ -226,6 +226,12 @@ func floatDecoder(bits int) MapperFunc {
 	}
 }
 
+func mapDecoder(d *Registry) MapperFunc {
+	return func(ctx *DecodeContext, target reflect.Value) error {
+		return nil
+	}
+}
+
 func sliceDecoder(d *Registry) MapperFunc {
 	return func(ctx *DecodeContext, target reflect.Value) error {
 		el := target.Type().Elem()
@@ -242,7 +248,7 @@ func sliceDecoder(d *Registry) MapperFunc {
 		if childDecoder == nil {
 			return fmt.Errorf("no mapper for element type of %s", target.Type())
 		}
-		for childScanner.Peek().Type != EOLToken {
+		for !childScanner.Peek().IsEOL() {
 			childValue := reflect.New(el).Elem()
 			err := childDecoder.Decode(ctx.WithScanner(childScanner), childValue)
 			if err != nil {

model.go

@@ -139,7 +139,7 @@ type Value struct {
 	Default  string
 	Mapper   Mapper
 	Tag      *Tag
-	Value    reflect.Value
+	Target   reflect.Value
 	Required bool
 	Set      bool   // Set to true when this value is set through some mechanism.
 	Format   string // Formatting directive, if applicable.
@@ -166,7 +166,7 @@ func (v *Value) Summary() string {
 
 // IsCumulative returns true of the value is a slice.
 func (v *Value) IsCumulative() bool {
-	return v.Value.Kind() == reflect.Slice
+	return v.Target.Kind() == reflect.Slice
 }
 
 // IsBool returns true if the underlying value is a boolean.
@@ -174,12 +174,12 @@ func (v *Value) IsBool() bool {
 	if m, ok := v.Mapper.(BoolMapper); ok && m.IsBool() {
 		return true
 	}
-	return v.Value.Kind() == reflect.Bool
+	return v.Target.Kind() == reflect.Bool
 }
 
 // Parse tokens into value, parse, and validate, but do not write to the field.
 func (v *Value) Parse(scan *Scanner) (reflect.Value, error) {
-	value := reflect.New(v.Value.Type()).Elem()
+	value := reflect.New(v.Target.Type()).Elem()
 	err := v.Mapper.Decode(&DecodeContext{Value: v, Scan: scan}, value)
 	if err == nil {
 		v.Set = true
@@ -189,7 +189,7 @@ func (v *Value) Parse(scan *Scanner) (reflect.Value, error) {
 
 // Apply value to field.
 func (v *Value) Apply(value reflect.Value) {
-	v.Value.Set(value)
+	v.Target.Set(value)
 	v.Set = true
 }
 
@@ -197,7 +197,7 @@ func (v *Value) Apply(value reflect.Value) {
 //
 // Does not include resolvers.
 func (v *Value) Reset() error {
-	v.Value.Set(reflect.Zero(v.Value.Type()))
+	v.Target.Set(reflect.Zero(v.Target.Type()))
 	if v.Default != "" {
 		value, err := v.Parse(Scan(v.Default))
 		if err != nil {
@@ -239,7 +239,7 @@ func (f *Flag) FormatPlaceHolder() string {
 		tail += ", ..."
 	}
 	if f.Default != "" {
-		if f.Value.Value.Kind() == reflect.String {
+		if f.Value.Target.Kind() == reflect.String {
 			return strconv.Quote(f.Default) + tail
 		}
 		return f.Default + tail