Add support for ansi

Signed-off-by: Richie Bendall <richiebendall@gmail.com>

index.d.ts

@@ -183,6 +183,14 @@ export interface ChalkInstance extends ChalkFunction {
 	*/
 	hex: (color: string) => this;
 
+	/**
+	Use a [Select/Set Graphic Rendition](https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_parameters) (SGR) [color code number](https://en.wikipedia.org/wiki/ANSI_escape_code#3/4_bit) to set text color.
+
+	30 <= code && code < 38 || 90 <= code && code < 98
+	For example, 31 for red, 91 for redBright.
+	*/
+	ansi: (code: number) => this;
+
 	/**
 	Use a [8-bit unsigned number](https://en.wikipedia.org/wiki/ANSI_escape_code#8-bit) to set text color.
 	*/
@@ -207,6 +215,14 @@ export interface ChalkInstance extends ChalkFunction {
 	*/
 	bgHex: (color: string) => this;
 
+	/**
+	Use a [Select/Set Graphic Rendition](https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_parameters) (SGR) [color code number](https://en.wikipedia.org/wiki/ANSI_escape_code#3/4_bit) to set background color.
+	30 <= code && code < 38 || 90 <= code && code < 98
+	For example, 31 for red, 91 for redBright.
+	Use the foreground code, not the background code (for example, not 41, nor 101).
+	*/
+	bgAnsi: (code: number) => this;
+
 	/**
 	Use a [8-bit unsigned number](https://en.wikipedia.org/wiki/ANSI_escape_code#8-bit) to set background color.
 	*/

index.test-d.ts

@@ -43,9 +43,11 @@ expectType<string>(chalk`Works with numbers {bold.red ${1}}`);
 // -- Color methods --
 expectAssignable<colorReturn>(chalk.rgb(0, 0, 0));
 expectAssignable<colorReturn>(chalk.hex('#DEADED'));
+expectAssignable<colorReturn>(chalk.ansi(30));
 expectAssignable<colorReturn>(chalk.ansi256(0));
 expectAssignable<colorReturn>(chalk.bgRgb(0, 0, 0));
 expectAssignable<colorReturn>(chalk.bgHex('#DEADED'));
+expectAssignable<colorReturn>(chalk.bgAnsi(30));
 expectAssignable<colorReturn>(chalk.bgAnsi256(0));
 
 // -- Modifiers --

package.json

@@ -42,7 +42,7 @@
 		"text"
 	],
 	"dependencies": {
-		"ansi-styles": "^6.0.0",
+		"ansi-styles": "^6.1.0",
 		"supports-color": "^9.0.0"
 	},
 	"devDependencies": {

readme.md

@@ -298,6 +298,7 @@ The following color models can be used:
 
 - [`rgb`](https://en.wikipedia.org/wiki/RGB_color_model) - Example: `chalk.rgb(255, 136, 0).bold('Orange!')`
 - [`hex`](https://en.wikipedia.org/wiki/Web_colors#Hex_triplet) - Example: `chalk.hex('#FF8800').bold('Orange!')`
+- [`ansi`](https://en.wikipedia.org/wiki/ANSI_escape_code#3/4_bit) - Example: `chalk.ansi(31).bgAnsi(93)('red on yellowBright')`
 - [`ansi256`](https://en.wikipedia.org/wiki/ANSI_escape_code#8-bit) - Example: `chalk.bgAnsi256(194)('Honeydew, more or less')`
 
 ## Browser support

source/index.js

@@ -11,8 +11,8 @@ const {isArray} = Array;
 
 // `supportsColor.level` → `ansiStyles.color[name]` mapping
 const levelMapping = [
-	'ansi256',
+	'ansi',
-	'ansi256',
+	'ansi',
 	'ansi256',
 	'ansi16m'
 ];
@@ -74,7 +74,15 @@ styles.visible = {
 
 const getModelAnsi = (model, level, type, ...arguments_) => {
 	if (model === 'rgb') {
-		return level === 'ansi16m' ? ansiStyles[type].ansi16m(...arguments_) : ansiStyles[type].ansi256(ansiStyles.rgbToAnsi256(...arguments_));
+		if (level === 'ansi16m') {
+			return ansiStyles[type].ansi16m(...arguments_);
+		}
+
+		if (level === 'ansi256') {
+			return ansiStyles[type].ansi256(ansiStyles.rgbToAnsi256(...arguments_));
+		}
+
+		return ansiStyles[type].ansi(ansiStyles.rgbToAnsi(...arguments_));
 	}
 
 	if (model === 'hex') {
@@ -84,7 +92,7 @@ const getModelAnsi = (model, level, type, ...arguments_) => {
 	return ansiStyles[type](...arguments_);
 };
 
-const usedModels = ['rgb', 'hex', 'ansi256'];
+const usedModels = ['rgb', 'hex', 'ansi256', 'ansi'];
 
 for (const model of usedModels) {
 	styles[model] = {

test/chalk.js

@@ -93,6 +93,11 @@ test('line breaks should open and close colors with CRLF', t => {
 	t.is(chalk.grey('hello\r\nworld'), '\u001B[90mhello\u001B[39m\r\n\u001B[90mworld\u001B[39m');
 });
 
+test('properly convert RGB to 16 colors on basic color terminals', t => {
+	t.is(new Chalk({level: 1}).hex('#FF0000')('hello'), '\u001B[91mhello\u001B[39m');
+	t.is(new Chalk({level: 1}).bgHex('#FF0000')('hello'), '\u001B[101mhello\u001B[49m');
+});
+
 test('properly convert RGB to 256 colors on basic color terminals', t => {
 	t.is(new Chalk({level: 2}).hex('#FF0000')('hello'), '\u001B[38;5;196mhello\u001B[39m');
 	t.is(new Chalk({level: 2}).bgHex('#FF0000')('hello'), '\u001B[48;5;196mhello\u001B[49m');