Modernize source code

command.go

@@ -90,7 +90,7 @@ type Command struct {
 	// default behavior.
 	ExitErrHandler ExitErrHandlerFunc `json:"-"`
 	// Other custom info
-	Metadata map[string]interface{} `json:"metadata"`
+	Metadata map[string]any `json:"metadata"`
 	// Carries a function which returns app specific info.
 	ExtraInfo func() map[string]string `json:"-"`
 	// CustomRootCommandHelpTemplate the text template for app help topic.
@@ -559,7 +559,7 @@ func (cmd *Command) Count(name string) int {
 }
 
 // Value returns the value of the flag corresponding to `name`
-func (cmd *Command) Value(name string) interface{} {
+func (cmd *Command) Value(name string) any {
 	if fs := cmd.lookupFlag(name); fs != nil {
 		tracef("value found for name %[1]q (cmd=%[2]q)", name, cmd.Name)
 		return fs.Get()

command_test.go

@@ -1973,7 +1973,7 @@ func TestCommandHelpPrinter(t *testing.T) {
 	}()
 
 	wasCalled := false
-	HelpPrinter = func(io.Writer, string, interface{}) {
+	HelpPrinter = func(io.Writer, string, any) {
 		wasCalled = true
 	}
 
@@ -5420,7 +5420,7 @@ func TestCommand_ExclusiveFlagsWithAfter(t *testing.T) {
 func TestCommand_ParallelRun(t *testing.T) {
 	t.Parallel()
 
-	for i := 0; i < 10; i++ {
+	for i := range 10 {
 		t.Run(fmt.Sprintf("run_%d", i), func(t *testing.T) {
 			t.Parallel()
 

completion_test.go

@@ -69,15 +69,15 @@ func TestCompletionSubcommand(t *testing.T) {
 		args        []string
 		contains    string
 		msg         string
-		msgArgs     []interface{}
+		msgArgs     []any
 		notContains bool
 	}{
 		{
 			name:     "subcommand general completion",
 			args:     []string{"foo", "bar", completionFlag},
 			contains: "xyz",
 			msg:      "Expected output to contain shell name %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"xyz",
 			},
 		},
@@ -86,7 +86,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "-", completionFlag},
 			contains: "l1",
 			msg:      "Expected output to contain shell name %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"l1",
 			},
 		},
@@ -95,7 +95,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "--", completionFlag},
 			contains: "l1",
 			msg:      "Expected output to contain shell name %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"l1",
 			},
 			notContains: true,
@@ -105,7 +105,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "xyz", completionFlag},
 			contains: "-g",
 			msg:      "Expected output to contain flag %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"-g",
 			},
 			notContains: true,
@@ -115,7 +115,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "xyz", "-", completionFlag},
 			contains: "-g",
 			msg:      "Expected output to contain flag %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"-g",
 			},
 		},
@@ -124,7 +124,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "xyz", "--", completionFlag},
 			contains: "-g",
 			msg:      "Expected output to contain flag %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"-g",
 			},
 			notContains: true,
@@ -134,7 +134,7 @@ func TestCompletionSubcommand(t *testing.T) {
 			args:     []string{"foo", "bar", "xyz", "--", "sargs", completionFlag},
 			contains: "-g",
 			msg:      "Expected output to contain flag %[1]q",
-			msgArgs: []interface{}{
+			msgArgs: []any{
 				"-g",
 			},
 			notContains: true,

docs.go

@@ -35,21 +35,21 @@ func unquoteUsage(usage string) (string, string) {
 }
 
 func prefixedNames(names []string, placeholder string) string {
-	var prefixed string
+	var prefixed strings.Builder
 	for i, name := range names {
 		if name == "" {
 			continue
 		}
 
-		prefixed += prefixFor(name) + name
+		prefixed.WriteString(prefixFor(name) + name)
 		if placeholder != "" {
-			prefixed += " " + placeholder
+			prefixed.WriteString(" " + placeholder)
 		}
 		if i < len(names)-1 {
-			prefixed += ", "
+			prefixed.WriteString(", ")
 		}
 	}
-	return prefixed
+	return prefixed.String()
 }
 
 func envFormat(envVars []string, prefix, sep, suffix string) string {

flag.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"regexp"
+	"slices"
 	"strings"
 	"time"
 )
@@ -208,13 +209,7 @@ func FlagNames(name string, aliases []string) []string {
 }
 
 func hasFlag(flags []Flag, fl Flag) bool {
-	for _, existing := range flags {
-		if fl == existing {
-			return true
-		}
-	}
-
-	return false
+	return slices.Contains(flags, fl)
 }
 
 func flagSplitMultiValues(val string, sliceSeparator string, disableSliceSeparator bool) []string {

flag_bool.go

@@ -69,7 +69,7 @@ func (b *boolValue) Set(s string) error {
 	return err
 }
 
-func (b *boolValue) Get() interface{} { return *b.destination }
+func (b *boolValue) Get() any { return *b.destination }
 
 func (b *boolValue) String() string {
 	return strconv.FormatBool(*b.destination)

flag_map_impl.go

@@ -115,7 +115,7 @@ func (i *MapBase[T, C, VC]) Value() map[string]T {
 }
 
 // Get returns the mapping of values set by this flag
-func (i *MapBase[T, C, VC]) Get() interface{} {
+func (i *MapBase[T, C, VC]) Get() any {
 	return *i.dict
 }
 

flag_slice_base.go

@@ -105,7 +105,7 @@ func (i *SliceBase[T, C, VC]) Value() []T {
 }
 
 // Get returns the slice of values set by this flag
-func (i *SliceBase[T, C, VC]) Get() interface{} {
+func (i *SliceBase[T, C, VC]) Get() any {
 	return *i.slice
 }
 

flag_test.go

@@ -36,7 +36,7 @@ func (p *Parser) String() string {
 	return fmt.Sprintf("%s,%s", p[0], p[1])
 }
 
-func (p *Parser) Get() interface{} {
+func (p *Parser) Get() any {
 	return p
 }
 

godoc-current.txt

@@ -499,7 +499,7 @@ type Command struct {
 	// default behavior.
 	ExitErrHandler ExitErrHandlerFunc `json:"-"`
 	// Other custom info
-	Metadata map[string]interface{} `json:"metadata"`
+	Metadata map[string]any `json:"metadata"`
 	// Carries a function which returns app specific info.
 	ExtraInfo func() map[string]string `json:"-"`
 	// CustomRootCommandHelpTemplate the text template for app help topic.
@@ -777,7 +777,7 @@ func (cmd *Command) UintSlice(name string) []uint
     UintSlice looks up the value of a local UintSliceFlag, returns nil if not
     found
 
-func (cmd *Command) Value(name string) interface{}
+func (cmd *Command) Value(name string) any
     Value returns the value of the flag corresponding to `name`
 
 func (cmd *Command) VisibleCategories() []CommandCategory
@@ -1225,7 +1225,7 @@ func NewMapBase[T any, C any, VC ValueCreator[T, C]](defaults map[string]T) *Map
 
 func (i MapBase[T, C, VC]) Create(val map[string]T, p *map[string]T, c C) Value
 
-func (i *MapBase[T, C, VC]) Get() interface{}
+func (i *MapBase[T, C, VC]) Get() any
     Get returns the mapping of values set by this flag
 
 func (i *MapBase[T, C, VC]) Serialize() string
@@ -1312,7 +1312,7 @@ func NewSliceBase[T any, C any, VC ValueCreator[T, C]](defaults ...T) *SliceBase
 
 func (i SliceBase[T, C, VC]) Create(val []T, p *[]T, c C) Value
 
-func (i *SliceBase[T, C, VC]) Get() interface{}
+func (i *SliceBase[T, C, VC]) Get() any
     Get returns the slice of values set by this flag
 
 func (i *SliceBase[T, C, VC]) Serialize() string

help.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"slices"
 	"strings"
 	"text/tabwriter"
 	"text/template"
@@ -204,10 +205,8 @@ func cliArgContains(flagName string, args []string) bool {
 			count = 2
 		}
 		flag := fmt.Sprintf("%s%s", strings.Repeat("-", count), name)
-		for _, a := range args {
-			if a == flag {
-				return true
-			}
+		if slices.Contains(args, flag) {
+			return true
 		}
 	}
 	return false
@@ -496,13 +495,11 @@ func checkShellCompleteFlag(c *Command, arguments []string) (bool, []string) {
 		return false, arguments
 	}
 
-	for _, arg := range arguments {
-		// If arguments include "--", shell completion is disabled
-		// because after "--" only positional arguments are accepted.
-		// https://unix.stackexchange.com/a/11382
-		if arg == "--" {
-			return false, arguments[:pos]
-		}
+	// If arguments include "--", shell completion is disabled
+	// because after "--" only positional arguments are accepted.
+	// https://unix.stackexchange.com/a/11382
+	if slices.Contains(arguments, "--") {
+		return false, arguments[:pos]
 	}
 
 	return true, arguments[:pos]

help_test.go

@@ -481,7 +481,7 @@ func TestShowCommandHelp_HelpPrinter(t *testing.T) {
 		{
 			name:     "no-command",
 			template: "",
-			printer: func(w io.Writer, _ string, _ interface{}) {
+			printer: func(w io.Writer, _ string, _ any) {
 				fmt.Fprint(w, "yo")
 			},
 			command:      "",
@@ -517,7 +517,7 @@ func TestShowCommandHelp_HelpPrinter(t *testing.T) {
 			defer func(old HelpPrinterFunc) {
 				HelpPrinter = old
 			}(HelpPrinter)
-			HelpPrinter = func(w io.Writer, templ string, data interface{}) {
+			HelpPrinter = func(w io.Writer, templ string, data any) {
 				assert.Equal(t, tt.wantTemplate, templ, "template mismatch")
 				tt.printer(w, templ, data)
 			}
@@ -947,7 +947,7 @@ func TestShowRootCommandHelp_HelpPrinter(t *testing.T) {
 		{
 			name:     "standard-command",
 			template: "",
-			printer: func(w io.Writer, _ string, _ interface{}) {
+			printer: func(w io.Writer, _ string, _ any) {
 				fmt.Fprint(w, "yo")
 			},
 			wantTemplate: RootCommandHelpTemplate,
@@ -956,7 +956,7 @@ func TestShowRootCommandHelp_HelpPrinter(t *testing.T) {
 		{
 			name:     "custom-template-command",
 			template: "{{doublecho .Name}}",
-			printer: func(w io.Writer, templ string, data interface{}) {
+			printer: func(w io.Writer, templ string, data any) {
 				// Pass a custom function to ensure it gets used
 				fm := map[string]any{"doublecho": doublecho}
 				DefaultPrintHelpCustom(w, templ, data, fm)
@@ -971,7 +971,7 @@ func TestShowRootCommandHelp_HelpPrinter(t *testing.T) {
 			defer func(old HelpPrinterFunc) {
 				HelpPrinter = old
 			}(HelpPrinter)
-			HelpPrinter = func(w io.Writer, templ string, data interface{}) {
+			HelpPrinter = func(w io.Writer, templ string, data any) {
 				assert.Equal(t, tt.wantTemplate, templ, "unexpected template")
 				tt.printer(w, templ, data)
 			}
@@ -1006,7 +1006,7 @@ func TestShowRootCommandHelp_HelpPrinterCustom(t *testing.T) {
 		{
 			name:     "standard-command",
 			template: "",
-			printer: func(w io.Writer, _ string, _ interface{}, _ map[string]interface{}) {
+			printer: func(w io.Writer, _ string, _ any, _ map[string]any) {
 				fmt.Fprint(w, "yo")
 			},
 			wantTemplate: RootCommandHelpTemplate,
@@ -1015,7 +1015,7 @@ func TestShowRootCommandHelp_HelpPrinterCustom(t *testing.T) {
 		{
 			name:     "custom-template-command",
 			template: "{{doublecho .Name}}",
-			printer: func(w io.Writer, templ string, data interface{}, _ map[string]interface{}) {
+			printer: func(w io.Writer, templ string, data any, _ map[string]any) {
 				// Pass a custom function to ensure it gets used
 				fm := map[string]any{"doublecho": doublecho}
 				DefaultPrintHelpCustom(w, templ, data, fm)
@@ -1030,7 +1030,7 @@ func TestShowRootCommandHelp_HelpPrinterCustom(t *testing.T) {
 			defer func(old HelpPrinterCustomFunc) {
 				HelpPrinterCustom = old
 			}(HelpPrinterCustom)
-			HelpPrinterCustom = func(w io.Writer, templ string, data interface{}, fm map[string]interface{}) {
+			HelpPrinterCustom = func(w io.Writer, templ string, data any, fm map[string]any) {
 				assert.Nil(t, fm, "unexpected function map passed")
 				assert.Equal(t, tt.wantTemplate, templ, "unexpected template")
 				tt.printer(w, templ, data, fm)
@@ -1514,8 +1514,8 @@ Including newlines.
 And then another long line. Blah blah blah does anybody ever read these things?`,
 	}
 
-	HelpPrinter = func(w io.Writer, templ string, data interface{}) {
-		funcMap := map[string]interface{}{
+	HelpPrinter = func(w io.Writer, templ string, data any) {
+		funcMap := map[string]any{
 			"wrapAt": func() int {
 				return 30
 			},
@@ -1597,8 +1597,8 @@ func TestWrappedCommandHelp(t *testing.T) {
 	cmd.setupDefaults([]string{"cli.test"})
 	cmd.setupCommandGraph()
 
-	HelpPrinter = func(w io.Writer, templ string, data interface{}) {
-		funcMap := map[string]interface{}{
+	HelpPrinter = func(w io.Writer, templ string, data any) {
+		funcMap := map[string]any{
 			"wrapAt": func() int {
 				return 30
 			},
@@ -1665,8 +1665,8 @@ func TestWrappedSubcommandHelp(t *testing.T) {
 		},
 	}
 
-	HelpPrinter = func(w io.Writer, templ string, data interface{}) {
-		funcMap := map[string]interface{}{
+	HelpPrinter = func(w io.Writer, templ string, data any) {
+		funcMap := map[string]any{
 			"wrapAt": func() int {
 				return 30
 			},
@@ -1737,8 +1737,8 @@ func TestWrappedHelpSubcommand(t *testing.T) {
 		},
 	}
 
-	HelpPrinter = func(w io.Writer, templ string, data interface{}) {
-		funcMap := map[string]interface{}{
+	HelpPrinter = func(w io.Writer, templ string, data any) {
+		funcMap := map[string]any{
 			"wrapAt": func() int {
 				return 30
 			},
@@ -1821,8 +1821,8 @@ func TestCategorizedHelp(t *testing.T) {
 		},
 	}
 
-	HelpPrinter = func(w io.Writer, templ string, data interface{}) {
-		funcMap := map[string]interface{}{
+	HelpPrinter = func(w io.Writer, templ string, data any) {
+		funcMap := map[string]any{
 			"wrapAt": func() int {
 				return 30
 			},