Get all ansi escape sequences (#25)

Co-Authored-By: Sindre Sorhus <[email protected]>

Author: TiagoDanin

index.js

@@ -8,27 +8,68 @@ const ESCAPES = [
 	'\u009B'
 ];
 
-const END_CODE = 39;
-
 const wrapAnsi = code => `${ESCAPES[0]}[${code}m`;
 
+const checkAnsi = (ansiCodes, isEscapes, endAnsiCode) => {
+	let output = [];
+	ansiCodes = [...ansiCodes];
+
+	for (let ansiCode of ansiCodes) {
+		const ansiCodeOrigin = ansiCode;
+		if (ansiCode.match(';')) {
+			ansiCode = ansiCode.split(';')[0][0] + '0';
+		}
+
+		const item = ansiStyles.codes.get(parseInt(ansiCode, 10));
+		if (item) {
+			const indexEscape = ansiCodes.indexOf(item.toString());
+			if (indexEscape >= 0) {
+				ansiCodes.splice(indexEscape, 1);
+			} else {
+				output.push(wrapAnsi(isEscapes ? item : ansiCodeOrigin));
+			}
+		} else if (isEscapes) {
+			output.push(wrapAnsi(0));
+			break;
+		} else {
+			output.push(wrapAnsi(ansiCodeOrigin));
+		}
+	}
+
+	if (isEscapes) {
+		output = output.filter((element, index) => output.indexOf(element) === index);
+		if (endAnsiCode !== undefined) {
+			const fistEscapeCode = wrapAnsi(ansiStyles.codes.get(parseInt(endAnsiCode, 10)));
+			output = output.reduce((current, next) => next === fistEscapeCode ? [next, ...current] : [...current, next], []);
+		}
+	}
+
+	return output.join('');
+};
+
 module.exports = (string, begin, end) => {
 	const characters = [...string.normalize()];
+	const ansiCodes = [];
 
 	end = typeof end === 'number' ? end : characters.length;
 
 	let isInsideEscape = false;
-	let escapeCode;
+	let ansiCode;
 	let visible = 0;
 	let output = '';
 
 	for (const [index, character] of characters.entries()) {
 		let leftEscape = false;
 
 		if (ESCAPES.includes(character)) {
-			isInsideEscape = true;
 			const code = /\d[^m]*/.exec(string.slice(index, index + 18));
-			escapeCode = code === END_CODE ? undefined : code;
+			ansiCode = code && code.length > 0 ? code[0] : undefined;
+			if (visible < end) {
+				isInsideEscape = true;
+				if (ansiCode !== undefined) {
+					ansiCodes.push(ansiCode);
+				}
+			}
 		} else if (isInsideEscape && character === 'm') {
 			isInsideEscape = false;
 			leftEscape = true;
@@ -44,13 +85,10 @@ module.exports = (string, begin, end) => {
 
 		if (visible > begin && visible <= end) {
 			output += character;
-		} else if (visible === begin && !isInsideEscape && escapeCode !== undefined && escapeCode !== END_CODE) {
-			output += wrapAnsi(escapeCode);
+		} else if (visible === begin && !isInsideEscape && ansiCode !== undefined) {
+			output = checkAnsi(ansiCodes);
 		} else if (visible >= end) {
-			if (escapeCode !== undefined) {
-				output += wrapAnsi(ansiStyles.codes.get(parseInt(escapeCode, 10)) || END_CODE);
-			}
-
+			output += checkAnsi(ansiCodes, true, ansiCode);
 			break;
 		}
 	}

test.js

@@ -24,9 +24,9 @@ test('main', t => {
 		}
 	}
 
-	const a = util.inspect('\u001B[31mthe \u001B[39m\u001B[32mquick \u001B[39m\u001B[34m\u001B[39m');
-	const b = util.inspect('\u001B[32m\u001B[39m\u001B[34mbrown \u001B[39m\u001B[36mfox \u001B[39m\u001B[33m\u001B[39m');
-	const c = util.inspect('\u001B[31m \u001B[39m\u001B[32mquick \u001B[39m\u001B[34mbrown \u001B[39m\u001B[36mfox \u001B[39m\u001B[33m\u001B[39m');
+	const a = util.inspect('\u001B[31mthe \u001B[39m\u001B[32mquick \u001B[39m');
+	const b = util.inspect('\u001B[34mbrown \u001B[39m\u001B[36mfox \u001B[39m');
+	const c = util.inspect('\u001B[31m \u001B[39m\u001B[32mquick \u001B[39m\u001B[34mbrown \u001B[39m\u001B[36mfox \u001B[39m');
 
 	t.is(util.inspect(sliceAnsi(fixture, 0, 10)), a);
 	t.is(util.inspect(sliceAnsi(fixture, 10, 20)), b);
@@ -50,33 +50,45 @@ test('doesn\'t add unnecessary escape codes', t => {
 	t.is(sliceAnsi('\u001B[31municorn\u001B[39m', 0, 3), '\u001B[31muni\u001B[39m');
 });
 
-test.failing('can slice a normal character before a colored character', t => {
+test('can slice a normal character before a colored character', t => {
 	t.is(sliceAnsi('a\u001B[31mb\u001B[39m', 0, 1), 'a');
 });
 
-test.failing('can slice a normal character after a colored character', t => {
+test('can slice a normal character after a colored character', t => {
 	t.is(sliceAnsi('\u001B[31ma\u001B[39mb', 1, 2), 'b');
 });
 
 // See https://github.com/chalk/slice-ansi/issues/22
-test.failing('can slice a string styled with both background and foreground', t => {
+test('can slice a string styled with both background and foreground', t => {
 	// Test string: `chalk.bgGreen.black('test');`
 	t.is(sliceAnsi('\u001B[42m\u001B[30mtest\u001B[39m\u001B[49m', 0, 1), '\u001B[42m\u001B[30mt\u001B[39m\u001B[49m');
 });
 
+test('can slice a string styled with modifier', t => {
+	// Test string: `chalk.underline('test');`
+	t.is(sliceAnsi('\u001B[4mtest\u001B[24m', 0, 1), '\u001B[4mt\u001B[24m');
+});
+
+test('can slice a string with unknown ANSI color', t => {
+	t.is(sliceAnsi('\u001B[20mTEST\u001B[49m', 0, 4), '\u001B[20mTEST\u001B[0m');
+	t.is(sliceAnsi('\u001B[1001mTEST\u001B[49m', 0, 3), '\u001B[1001mTES\u001B[0m');
+	t.is(sliceAnsi('\u001B[1001mTEST\u001B[49m', 0, 2), '\u001B[1001mTE\u001B[0m');
+});
+
 test('weird null issue', t => {
 	const s = '\u001B[1mautotune.flipCoin("easy as") ? 🎂 : 🍰 \u001B[33m★\u001B[39m\u001B[22m';
 	const result = sliceAnsi(s, 38);
 	t.false(result.includes('null'));
 });
 
 test('support true color escape sequences', t => {
-	t.is(sliceAnsi('\u001B[[1m\u001B[[48;2;255;255;255m\u001B[[38;2;255;0;0municorn\u001B[[39m\u001B[[49m\u001B[[22m', 0, 3), '\u001B[1m\u001B[48;2;255;255;25m\u001B[38;2;255;0;0muni\u001B[39m');
+	t.is(sliceAnsi('\u001B[1m\u001B[48;2;255;255;255m\u001B[38;2;255;0;0municorn\u001B[39m\u001B[49m\u001B[22m', 0, 3), '\u001B[1m\u001B[48;2;255;255;255m\u001B[38;2;255;0;0muni\u001B[22m\u001B[49m\u001B[39m');
 });
 
 // See https://github.com/chalk/slice-ansi/issues/24
-test.failing('doesn\'t add extra escapes', t => {
+test('doesn\'t add extra escapes', t => {
 	const output = `${chalk.black.bgYellow(' RUNS ')}  ${chalk.green('test')}`;
 	t.is(sliceAnsi(output, 0, 7), `${chalk.black.bgYellow(' RUNS ')} `);
 	t.is(sliceAnsi(output, 0, 8), `${chalk.black.bgYellow(' RUNS ')}  `);
+	t.is(sliceAnsi('\u001B[31m' + output, 0, 4), `\u001B[31m${chalk.black.bgYellow(' RUN')}`);
 });