lib/src/ansi_code.dart - third_party/io - Git at Google

 // Copyright 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 import 'dart:async';
 import 'dart:io' as io;

 const _ansiEscapeLiteral = '\x1B';
 const _ansiEscapeForScript = r'\033';

 /// Whether formatted ANSI output is enabled for [wrapWith] and [AnsiCode.wrap].
 ///
 /// By default, returns `true` if both `stdout.supportsAnsiEscapes` and
 /// `stderr.supportsAnsiEscapes` from `dart:io` are `true`.
 ///
 /// The default can be overridden by setting the [Zone] variable [AnsiCode] to
 /// either `true` or `false`.
 ///
 /// [overrideAnsiOutput] is provided to make this easy.
 bool get ansiOutputEnabled =>
     Zone.current[AnsiCode] as bool? ??
     (io.stdout.supportsAnsiEscapes && io.stderr.supportsAnsiEscapes);

 /// Returns `true` no formatting is required for [input].
 bool _isNoop(bool skip, String? input, bool? forScript) =>
     skip ||
     input == null ||
     input.isEmpty ||
     !((forScript ?? false) || ansiOutputEnabled);

 /// Allows overriding [ansiOutputEnabled] to [enableAnsiOutput] for the code run
 /// within [body].
 T overrideAnsiOutput<T>(bool enableAnsiOutput, T Function() body) =>
     runZoned(body, zoneValues: <Object, Object>{AnsiCode: enableAnsiOutput});

 /// The type of code represented by [AnsiCode].
 class AnsiCodeType {
   final String _name;

   /// A foreground color.
   static const AnsiCodeType foreground = AnsiCodeType._('foreground');

   /// A style.
   static const AnsiCodeType style = AnsiCodeType._('style');

   /// A background color.
   static const AnsiCodeType background = AnsiCodeType._('background');

   /// A reset value.
   static const AnsiCodeType reset = AnsiCodeType._('reset');

   const AnsiCodeType._(this._name);

   @override
   String toString() => 'AnsiType.$_name';
 }

 /// Standard ANSI escape code for customizing terminal text output.
 ///
 /// [Source](https://en.wikipedia.org/wiki/ANSI_escape_code#Colors)
 class AnsiCode {
   /// The numeric value associated with this code.
   final int code;

   /// The [AnsiCode] that resets this value, if one exists.
   ///
   /// Otherwise, `null`.
   final AnsiCode? reset;

   /// A description of this code.
   final String name;

   /// The type of code that is represented.
   final AnsiCodeType type;

   const AnsiCode._(this.name, this.type, this.code, this.reset);

   /// Represents the value escaped for use in terminal output.
   String get escape => '$_ansiEscapeLiteral[${code}m';

   /// Represents the value as an unescaped literal suitable for scripts.
   String get escapeForScript => '$_ansiEscapeForScript[${code}m';

   String _escapeValue({bool forScript = false}) =>
       forScript ? escapeForScript : escape;

   /// Wraps [value] with the [escape] value for this code, followed by
   /// [resetAll].
   ///
   /// If [forScript] is `true`, the return value is an unescaped literal. The
   /// value of [ansiOutputEnabled] is also ignored.
   ///
   /// Returns `value` unchanged if
   ///   * [value] is `null` or empty
   ///   * both [ansiOutputEnabled] and [forScript] are `false`.
   ///   * [type] is [AnsiCodeType.reset]
   String? wrap(String? value, {bool forScript = false}) =>
       _isNoop(type == AnsiCodeType.reset, value, forScript)
           ? value
           : '${_escapeValue(forScript: forScript)}$value'
               '${reset!._escapeValue(forScript: forScript)}';

   @override
   String toString() => '$name ${type._name} ($code)';
 }

 /// Returns a [String] formatted with [codes].
 ///
 /// If [forScript] is `true`, the return value is an unescaped literal. The
 /// value of [ansiOutputEnabled] is also ignored.
 ///
 /// Returns `value` unchanged if
 ///   * [value] is `null` or empty.
 ///   * both [ansiOutputEnabled] and [forScript] are `false`.
 ///   * [codes] is empty.
 ///
 /// Throws an [ArgumentError] if
 ///   * [codes] contains more than one value of type [AnsiCodeType.foreground].
 ///   * [codes] contains more than one value of type [AnsiCodeType.background].
 ///   * [codes] contains any value of type [AnsiCodeType.reset].
 String? wrapWith(String? value, Iterable<AnsiCode> codes,
     {bool forScript = false}) {
   // Eliminate duplicates
   final myCodes = codes.toSet();

   if (_isNoop(myCodes.isEmpty, value, forScript)) {
     return value;
   }

   var foreground = 0, background = 0;
   for (var code in myCodes) {
     switch (code.type) {
       case AnsiCodeType.foreground:
         foreground++;
         if (foreground > 1) {
           throw ArgumentError.value(codes, 'codes',
               'Cannot contain more than one foreground color code.');
         }
       case AnsiCodeType.background:
         background++;
         if (background > 1) {
           throw ArgumentError.value(codes, 'codes',
               'Cannot contain more than one foreground color code.');
         }
       case AnsiCodeType.reset:
         throw ArgumentError.value(
             codes, 'codes', 'Cannot contain reset codes.');
       case AnsiCodeType.style:
         // Ignore.
         break;
     }
   }

   final sortedCodes = myCodes.map((ac) => ac.code).toList()..sort();
   final escapeValue = forScript ? _ansiEscapeForScript : _ansiEscapeLiteral;

   return "$escapeValue[${sortedCodes.join(';')}m$value"
       '${resetAll._escapeValue(forScript: forScript)}';
 }

 //
 // Style values
 //

 const styleBold = AnsiCode._('bold', AnsiCodeType.style, 1, resetBold);
 const styleDim = AnsiCode._('dim', AnsiCodeType.style, 2, resetDim);
 const styleItalic = AnsiCode._('italic', AnsiCodeType.style, 3, resetItalic);
 const styleUnderlined =
     AnsiCode._('underlined', AnsiCodeType.style, 4, resetUnderlined);
 const styleBlink = AnsiCode._('blink', AnsiCodeType.style, 5, resetBlink);
 const styleReverse = AnsiCode._('reverse', AnsiCodeType.style, 7, resetReverse);

 /// Not widely supported.
 const styleHidden = AnsiCode._('hidden', AnsiCodeType.style, 8, resetHidden);

 /// Not widely supported.
 const styleCrossedOut =
     AnsiCode._('crossed out', AnsiCodeType.style, 9, resetCrossedOut);

 //
 // Reset values
 //

 const resetAll = AnsiCode._('all', AnsiCodeType.reset, 0, null);

 // NOTE: bold is weird. The reset code seems to be 22 sometimes – not 21
 // See https://gitlab.com/gnachman/iterm2/issues/3208
 const resetBold = AnsiCode._('bold', AnsiCodeType.reset, 22, null);
 const resetDim = AnsiCode._('dim', AnsiCodeType.reset, 22, null);
 const resetItalic = AnsiCode._('italic', AnsiCodeType.reset, 23, null);
 const resetUnderlined = AnsiCode._('underlined', AnsiCodeType.reset, 24, null);
 const resetBlink = AnsiCode._('blink', AnsiCodeType.reset, 25, null);
 const resetReverse = AnsiCode._('reverse', AnsiCodeType.reset, 27, null);
 const resetHidden = AnsiCode._('hidden', AnsiCodeType.reset, 28, null);
 const resetCrossedOut = AnsiCode._('crossed out', AnsiCodeType.reset, 29, null);

 //
 // Foreground values
 //

 const black = AnsiCode._('black', AnsiCodeType.foreground, 30, resetAll);
 const red = AnsiCode._('red', AnsiCodeType.foreground, 31, resetAll);
 const green = AnsiCode._('green', AnsiCodeType.foreground, 32, resetAll);
 const yellow = AnsiCode._('yellow', AnsiCodeType.foreground, 33, resetAll);
 const blue = AnsiCode._('blue', AnsiCodeType.foreground, 34, resetAll);
 const magenta = AnsiCode._('magenta', AnsiCodeType.foreground, 35, resetAll);
 const cyan = AnsiCode._('cyan', AnsiCodeType.foreground, 36, resetAll);
 const lightGray =
     AnsiCode._('light gray', AnsiCodeType.foreground, 37, resetAll);
 const defaultForeground =
     AnsiCode._('default', AnsiCodeType.foreground, 39, resetAll);
 const darkGray = AnsiCode._('dark gray', AnsiCodeType.foreground, 90, resetAll);
 const lightRed = AnsiCode._('light red', AnsiCodeType.foreground, 91, resetAll);
 const lightGreen =
     AnsiCode._('light green', AnsiCodeType.foreground, 92, resetAll);
 const lightYellow =
     AnsiCode._('light yellow', AnsiCodeType.foreground, 93, resetAll);
 const lightBlue =
     AnsiCode._('light blue', AnsiCodeType.foreground, 94, resetAll);
 const lightMagenta =
     AnsiCode._('light magenta', AnsiCodeType.foreground, 95, resetAll);
 const lightCyan =
     AnsiCode._('light cyan', AnsiCodeType.foreground, 96, resetAll);
 const white = AnsiCode._('white', AnsiCodeType.foreground, 97, resetAll);

 //
 // Background values
 //

 const backgroundBlack =
     AnsiCode._('black', AnsiCodeType.background, 40, resetAll);
 const backgroundRed = AnsiCode._('red', AnsiCodeType.background, 41, resetAll);
 const backgroundGreen =
     AnsiCode._('green', AnsiCodeType.background, 42, resetAll);
 const backgroundYellow =
     AnsiCode._('yellow', AnsiCodeType.background, 43, resetAll);
 const backgroundBlue =
     AnsiCode._('blue', AnsiCodeType.background, 44, resetAll);
 const backgroundMagenta =
     AnsiCode._('magenta', AnsiCodeType.background, 45, resetAll);
 const backgroundCyan =
     AnsiCode._('cyan', AnsiCodeType.background, 46, resetAll);
 const backgroundLightGray =
     AnsiCode._('light gray', AnsiCodeType.background, 47, resetAll);
 const backgroundDefault =
     AnsiCode._('default', AnsiCodeType.background, 49, resetAll);
 const backgroundDarkGray =
     AnsiCode._('dark gray', AnsiCodeType.background, 100, resetAll);
 const backgroundLightRed =
     AnsiCode._('light red', AnsiCodeType.background, 101, resetAll);
 const backgroundLightGreen =
     AnsiCode._('light green', AnsiCodeType.background, 102, resetAll);
 const backgroundLightYellow =
     AnsiCode._('light yellow', AnsiCodeType.background, 103, resetAll);
 const backgroundLightBlue =
     AnsiCode._('light blue', AnsiCodeType.background, 104, resetAll);
 const backgroundLightMagenta =
     AnsiCode._('light magenta', AnsiCodeType.background, 105, resetAll);
 const backgroundLightCyan =
     AnsiCode._('light cyan', AnsiCodeType.background, 106, resetAll);
 const backgroundWhite =
     AnsiCode._('white', AnsiCodeType.background, 107, resetAll);

 /// All of the [AnsiCode] values that represent [AnsiCodeType.style].
 const List<AnsiCode> styles = [
   styleBold,
   styleDim,
   styleItalic,
   styleUnderlined,
   styleBlink,
   styleReverse,
   styleHidden,
   styleCrossedOut
 ];

 /// All of the [AnsiCode] values that represent [AnsiCodeType.foreground].
 const List<AnsiCode> foregroundColors = [
   black,
   red,
   green,
   yellow,
   blue,
   magenta,
   cyan,
   lightGray,
   defaultForeground,
   darkGray,
   lightRed,
   lightGreen,
   lightYellow,
   lightBlue,
   lightMagenta,
   lightCyan,
   white
 ];

 /// All of the [AnsiCode] values that represent [AnsiCodeType.background].
 const List<AnsiCode> backgroundColors = [
   backgroundBlack,
   backgroundRed,
   backgroundGreen,
   backgroundYellow,
   backgroundBlue,
   backgroundMagenta,
   backgroundCyan,
   backgroundLightGray,
   backgroundDefault,
   backgroundDarkGray,
   backgroundLightRed,
   backgroundLightGreen,
   backgroundLightYellow,
   backgroundLightBlue,
   backgroundLightMagenta,
   backgroundLightCyan,
   backgroundWhite
 ];
	// Copyright 2017, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	import 'dart:async';
	import 'dart:io' as io;

	const _ansiEscapeLiteral = '\x1B';
	const _ansiEscapeForScript = r'\033';

	/// Whether formatted ANSI output is enabled for [wrapWith] and [AnsiCode.wrap].
	///
	/// By default, returns `true` if both `stdout.supportsAnsiEscapes` and
	/// `stderr.supportsAnsiEscapes` from `dart:io` are `true`.
	///
	/// The default can be overridden by setting the [Zone] variable [AnsiCode] to
	/// either `true` or `false`.
	///
	/// [overrideAnsiOutput] is provided to make this easy.
	bool get ansiOutputEnabled =>
	Zone.current[AnsiCode] as bool? ??
	(io.stdout.supportsAnsiEscapes && io.stderr.supportsAnsiEscapes);

	/// Returns `true` no formatting is required for [input].
	bool _isNoop(bool skip, String? input, bool? forScript) =>
	skip \|\|
	input == null \|\|
	input.isEmpty \|\|
	!((forScript ?? false) \|\| ansiOutputEnabled);

	/// Allows overriding [ansiOutputEnabled] to [enableAnsiOutput] for the code run
	/// within [body].
	T overrideAnsiOutput<T>(bool enableAnsiOutput, T Function() body) =>
	runZoned(body, zoneValues: <Object, Object>{AnsiCode: enableAnsiOutput});

	/// The type of code represented by [AnsiCode].
	class AnsiCodeType {
	final String _name;

	/// A foreground color.
	static const AnsiCodeType foreground = AnsiCodeType._('foreground');

	/// A style.
	static const AnsiCodeType style = AnsiCodeType._('style');

	/// A background color.
	static const AnsiCodeType background = AnsiCodeType._('background');

	/// A reset value.
	static const AnsiCodeType reset = AnsiCodeType._('reset');

	const AnsiCodeType._(this._name);

	@override
	String toString() => 'AnsiType.$_name';
	}

	/// Standard ANSI escape code for customizing terminal text output.
	///
	/// [Source](https://en.wikipedia.org/wiki/ANSI_escape_code#Colors)
	class AnsiCode {
	/// The numeric value associated with this code.
	final int code;

	/// The [AnsiCode] that resets this value, if one exists.
	///
	/// Otherwise, `null`.
	final AnsiCode? reset;

	/// A description of this code.
	final String name;

	/// The type of code that is represented.
	final AnsiCodeType type;

	const AnsiCode._(this.name, this.type, this.code, this.reset);

	/// Represents the value escaped for use in terminal output.
	String get escape => '$_ansiEscapeLiteral[${code}m';

	/// Represents the value as an unescaped literal suitable for scripts.
	String get escapeForScript => '$_ansiEscapeForScript[${code}m';

	String _escapeValue({bool forScript = false}) =>
	forScript ? escapeForScript : escape;

	/// Wraps [value] with the [escape] value for this code, followed by
	/// [resetAll].
	///
	/// If [forScript] is `true`, the return value is an unescaped literal. The
	/// value of [ansiOutputEnabled] is also ignored.
	///
	/// Returns `value` unchanged if
	/// * [value] is `null` or empty
	/// * both [ansiOutputEnabled] and [forScript] are `false`.
	/// * [type] is [AnsiCodeType.reset]
	String? wrap(String? value, {bool forScript = false}) =>
	_isNoop(type == AnsiCodeType.reset, value, forScript)
	? value
	: '${_escapeValue(forScript: forScript)}$value'
	'${reset!._escapeValue(forScript: forScript)}';

	@override
	String toString() => '$name ${type._name} ($code)';
	}

	/// Returns a [String] formatted with [codes].
	///
	/// If [forScript] is `true`, the return value is an unescaped literal. The
	/// value of [ansiOutputEnabled] is also ignored.
	///
	/// Returns `value` unchanged if
	/// * [value] is `null` or empty.
	/// * both [ansiOutputEnabled] and [forScript] are `false`.
	/// * [codes] is empty.
	///
	/// Throws an [ArgumentError] if
	/// * [codes] contains more than one value of type [AnsiCodeType.foreground].
	/// * [codes] contains more than one value of type [AnsiCodeType.background].
	/// * [codes] contains any value of type [AnsiCodeType.reset].
	String? wrapWith(String? value, Iterable<AnsiCode> codes,
	{bool forScript = false}) {
	// Eliminate duplicates
	final myCodes = codes.toSet();

	if (_isNoop(myCodes.isEmpty, value, forScript)) {
	return value;
	}

	var foreground = 0, background = 0;
	for (var code in myCodes) {
	switch (code.type) {
	case AnsiCodeType.foreground:
	foreground++;
	if (foreground > 1) {
	throw ArgumentError.value(codes, 'codes',
	'Cannot contain more than one foreground color code.');
	}
	case AnsiCodeType.background:
	background++;
	if (background > 1) {
	throw ArgumentError.value(codes, 'codes',
	'Cannot contain more than one foreground color code.');
	}
	case AnsiCodeType.reset:
	throw ArgumentError.value(
	codes, 'codes', 'Cannot contain reset codes.');
	case AnsiCodeType.style:
	// Ignore.
	break;
	}
	}

	final sortedCodes = myCodes.map((ac) => ac.code).toList()..sort();
	final escapeValue = forScript ? _ansiEscapeForScript : _ansiEscapeLiteral;

	return "$escapeValue[${sortedCodes.join(';')}m$value"
	'${resetAll._escapeValue(forScript: forScript)}';
	}

	//
	// Style values
	//

	const styleBold = AnsiCode._('bold', AnsiCodeType.style, 1, resetBold);
	const styleDim = AnsiCode._('dim', AnsiCodeType.style, 2, resetDim);
	const styleItalic = AnsiCode._('italic', AnsiCodeType.style, 3, resetItalic);
	const styleUnderlined =
	AnsiCode._('underlined', AnsiCodeType.style, 4, resetUnderlined);
	const styleBlink = AnsiCode._('blink', AnsiCodeType.style, 5, resetBlink);
	const styleReverse = AnsiCode._('reverse', AnsiCodeType.style, 7, resetReverse);

	/// Not widely supported.
	const styleHidden = AnsiCode._('hidden', AnsiCodeType.style, 8, resetHidden);

	/// Not widely supported.
	const styleCrossedOut =
	AnsiCode._('crossed out', AnsiCodeType.style, 9, resetCrossedOut);

	//
	// Reset values
	//

	const resetAll = AnsiCode._('all', AnsiCodeType.reset, 0, null);

	// NOTE: bold is weird. The reset code seems to be 22 sometimes – not 21
	// See https://gitlab.com/gnachman/iterm2/issues/3208
	const resetBold = AnsiCode._('bold', AnsiCodeType.reset, 22, null);
	const resetDim = AnsiCode._('dim', AnsiCodeType.reset, 22, null);
	const resetItalic = AnsiCode._('italic', AnsiCodeType.reset, 23, null);
	const resetUnderlined = AnsiCode._('underlined', AnsiCodeType.reset, 24, null);
	const resetBlink = AnsiCode._('blink', AnsiCodeType.reset, 25, null);
	const resetReverse = AnsiCode._('reverse', AnsiCodeType.reset, 27, null);
	const resetHidden = AnsiCode._('hidden', AnsiCodeType.reset, 28, null);
	const resetCrossedOut = AnsiCode._('crossed out', AnsiCodeType.reset, 29, null);

	//
	// Foreground values
	//

	const black = AnsiCode._('black', AnsiCodeType.foreground, 30, resetAll);
	const red = AnsiCode._('red', AnsiCodeType.foreground, 31, resetAll);
	const green = AnsiCode._('green', AnsiCodeType.foreground, 32, resetAll);
	const yellow = AnsiCode._('yellow', AnsiCodeType.foreground, 33, resetAll);
	const blue = AnsiCode._('blue', AnsiCodeType.foreground, 34, resetAll);
	const magenta = AnsiCode._('magenta', AnsiCodeType.foreground, 35, resetAll);
	const cyan = AnsiCode._('cyan', AnsiCodeType.foreground, 36, resetAll);
	const lightGray =
	AnsiCode._('light gray', AnsiCodeType.foreground, 37, resetAll);
	const defaultForeground =
	AnsiCode._('default', AnsiCodeType.foreground, 39, resetAll);
	const darkGray = AnsiCode._('dark gray', AnsiCodeType.foreground, 90, resetAll);
	const lightRed = AnsiCode._('light red', AnsiCodeType.foreground, 91, resetAll);
	const lightGreen =
	AnsiCode._('light green', AnsiCodeType.foreground, 92, resetAll);
	const lightYellow =
	AnsiCode._('light yellow', AnsiCodeType.foreground, 93, resetAll);
	const lightBlue =
	AnsiCode._('light blue', AnsiCodeType.foreground, 94, resetAll);
	const lightMagenta =
	AnsiCode._('light magenta', AnsiCodeType.foreground, 95, resetAll);
	const lightCyan =
	AnsiCode._('light cyan', AnsiCodeType.foreground, 96, resetAll);
	const white = AnsiCode._('white', AnsiCodeType.foreground, 97, resetAll);

	//
	// Background values
	//

	const backgroundBlack =
	AnsiCode._('black', AnsiCodeType.background, 40, resetAll);
	const backgroundRed = AnsiCode._('red', AnsiCodeType.background, 41, resetAll);
	const backgroundGreen =
	AnsiCode._('green', AnsiCodeType.background, 42, resetAll);
	const backgroundYellow =
	AnsiCode._('yellow', AnsiCodeType.background, 43, resetAll);
	const backgroundBlue =
	AnsiCode._('blue', AnsiCodeType.background, 44, resetAll);
	const backgroundMagenta =
	AnsiCode._('magenta', AnsiCodeType.background, 45, resetAll);
	const backgroundCyan =
	AnsiCode._('cyan', AnsiCodeType.background, 46, resetAll);
	const backgroundLightGray =
	AnsiCode._('light gray', AnsiCodeType.background, 47, resetAll);
	const backgroundDefault =
	AnsiCode._('default', AnsiCodeType.background, 49, resetAll);
	const backgroundDarkGray =
	AnsiCode._('dark gray', AnsiCodeType.background, 100, resetAll);
	const backgroundLightRed =
	AnsiCode._('light red', AnsiCodeType.background, 101, resetAll);
	const backgroundLightGreen =
	AnsiCode._('light green', AnsiCodeType.background, 102, resetAll);
	const backgroundLightYellow =
	AnsiCode._('light yellow', AnsiCodeType.background, 103, resetAll);
	const backgroundLightBlue =
	AnsiCode._('light blue', AnsiCodeType.background, 104, resetAll);
	const backgroundLightMagenta =
	AnsiCode._('light magenta', AnsiCodeType.background, 105, resetAll);
	const backgroundLightCyan =
	AnsiCode._('light cyan', AnsiCodeType.background, 106, resetAll);
	const backgroundWhite =
	AnsiCode._('white', AnsiCodeType.background, 107, resetAll);

	/// All of the [AnsiCode] values that represent [AnsiCodeType.style].
	const List<AnsiCode> styles = [
	styleBold,
	styleDim,
	styleItalic,
	styleUnderlined,
	styleBlink,
	styleReverse,
	styleHidden,
	styleCrossedOut
	];

	/// All of the [AnsiCode] values that represent [AnsiCodeType.foreground].
	const List<AnsiCode> foregroundColors = [
	black,
	red,
	green,
	yellow,
	blue,
	magenta,
	cyan,
	lightGray,
	defaultForeground,
	darkGray,
	lightRed,
	lightGreen,
	lightYellow,
	lightBlue,
	lightMagenta,
	lightCyan,
	white
	];

	/// All of the [AnsiCode] values that represent [AnsiCodeType.background].
	const List<AnsiCode> backgroundColors = [
	backgroundBlack,
	backgroundRed,
	backgroundGreen,
	backgroundYellow,
	backgroundBlue,
	backgroundMagenta,
	backgroundCyan,
	backgroundLightGray,
	backgroundDefault,
	backgroundDarkGray,
	backgroundLightRed,
	backgroundLightGreen,
	backgroundLightYellow,
	backgroundLightBlue,
	backgroundLightMagenta,
	backgroundLightCyan,
	backgroundWhite
	];