89 lines
1.6 KiB
JavaScript
Executable File
89 lines
1.6 KiB
JavaScript
Executable File
'use strict';
|
|
const isFullwidthCodePoint = require('is-fullwidth-code-point');
|
|
|
|
const ESCAPES = [
|
|
'\u001B',
|
|
'\u009B'
|
|
];
|
|
|
|
const END_CODE = 39;
|
|
const ASTRAL_REGEX = /[\uD800-\uDBFF][\uDC00-\uDFFF]/;
|
|
|
|
const ESCAPE_CODES = new Map([
|
|
[0, 0],
|
|
[1, 22],
|
|
[2, 22],
|
|
[3, 23],
|
|
[4, 24],
|
|
[7, 27],
|
|
[8, 28],
|
|
[9, 29],
|
|
[30, 39],
|
|
[31, 39],
|
|
[32, 39],
|
|
[33, 39],
|
|
[34, 39],
|
|
[35, 39],
|
|
[36, 39],
|
|
[37, 39],
|
|
[90, 39],
|
|
[40, 49],
|
|
[41, 49],
|
|
[42, 49],
|
|
[43, 49],
|
|
[44, 49],
|
|
[45, 49],
|
|
[46, 49],
|
|
[47, 49]
|
|
]);
|
|
|
|
const wrapAnsi = code => `${ESCAPES[0]}[${code}m`;
|
|
|
|
module.exports = (str, begin, end) => {
|
|
const arr = Array.from(str.normalize());
|
|
|
|
end = typeof end === 'number' ? end : arr.length;
|
|
|
|
let insideEscape = false;
|
|
let escapeCode;
|
|
let visible = 0;
|
|
let output = '';
|
|
|
|
for (const item of arr.entries()) {
|
|
const i = item[0];
|
|
const x = item[1];
|
|
|
|
let leftEscape = false;
|
|
|
|
if (ESCAPES.indexOf(x) !== -1) {
|
|
insideEscape = true;
|
|
const code = /\d[^m]*/.exec(str.slice(i, i + 4));
|
|
escapeCode = code === END_CODE ? null : code;
|
|
} else if (insideEscape && x === 'm') {
|
|
insideEscape = false;
|
|
leftEscape = true;
|
|
}
|
|
|
|
if (!insideEscape && !leftEscape) {
|
|
++visible;
|
|
}
|
|
|
|
if (!ASTRAL_REGEX.test(x) && isFullwidthCodePoint(x.codePointAt())) {
|
|
++visible;
|
|
}
|
|
|
|
if (visible > begin && visible <= end) {
|
|
output += x;
|
|
} else if (visible === begin && !insideEscape && escapeCode !== undefined && escapeCode !== END_CODE) {
|
|
output += wrapAnsi(escapeCode);
|
|
} else if (visible >= end) {
|
|
if (escapeCode !== undefined) {
|
|
output += wrapAnsi(ESCAPE_CODES.get(parseInt(escapeCode, 10)) || END_CODE);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
return output;
|
|
};
|