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'use strict';
const stringWidth = require('string-width');
const stripAnsi = require('strip-ansi');
const ansiStyles = require('ansi-styles');
const ESCAPES = new Set([
'\u001B',
'\u009B'
]);
const END_CODE = 39;
const wrapAnsi = code => `${ESCAPES.values().next().value}[${code}m`;
// Calculate the length of words split on ' ', ignoring
// the extra characters added by ansi escape codes
const wordLengths = string => string.split(' ').map(character => stringWidth(character));
// Wrap a long word across multiple rows
// Ansi escape codes do not count towards length
const wrapWord = (rows, word, columns) => {
const characters = [...word];
let insideEscape = false;
let visible = stringWidth(stripAnsi(rows[rows.length - 1]));
for (const [index, character] of characters.entries()) {
const characterLength = stringWidth(character);
if (visible + characterLength <= columns) {
rows[rows.length - 1] += character;
} else {
rows.push(character);
visible = 0;
}
if (ESCAPES.has(character)) {
insideEscape = true;
} else if (insideEscape && character === 'm') {
insideEscape = false;
continue;
}
if (insideEscape) {
continue;
}
visible += characterLength;
if (visible === columns && index < characters.length - 1) {
rows.push('');
visible = 0;
}
}
// It's possible that the last row we copy over is only
// ansi escape characters, handle this edge-case
if (!visible && rows[rows.length - 1].length > 0 && rows.length > 1) {
rows[rows.length - 2] += rows.pop();
}
};
// Trims spaces from a string ignoring invisible sequences
const stringVisibleTrimSpacesRight = str => {
const words = str.split(' ');
let last = words.length;
while (last > 0) {
if (stringWidth(words[last - 1]) > 0) {
break;
}
last--;
}
if (last === words.length) {
return str;
}
return words.slice(0, last).join(' ') + words.slice(last).join('');
};
// The wrap-ansi module can be invoked
// in either 'hard' or 'soft' wrap mode
//
// 'hard' will never allow a string to take up more
// than columns characters
//
// 'soft' allows long words to expand past the column length
const exec = (string, columns, options = {}) => {
if (options.trim !== false && string.trim() === '') {
return '';
}
let pre = '';
let ret = '';
let escapeCode;
const lengths = wordLengths(string);
let rows = [''];
for (const [index, word] of string.split(' ').entries()) {
if (options.trim !== false) {
rows[rows.length - 1] = rows[rows.length - 1].trimLeft();
}
let rowLength = stringWidth(rows[rows.length - 1]);
if (index !== 0) {
if (rowLength >= columns && (options.wordWrap === false || options.trim === false)) {
// If we start with a new word but the current row length equals the length of the columns, add a new row
rows.push('');
rowLength = 0;
}
if (rowLength > 0 || options.trim === false) {
rows[rows.length - 1] += ' ';
rowLength++;
}
}
// In 'hard' wrap mode, the length of a line is
// never allowed to extend past 'columns'
if (options.hard && lengths[index] > columns) {
const remainingColumns = (columns - rowLength);
const breaksStartingThisLine = 1 + Math.floor((lengths[index] - remainingColumns - 1) / columns);
const breaksStartingNextLine = Math.floor((lengths[index] - 1) / columns);
if (breaksStartingNextLine < breaksStartingThisLine) {
rows.push('');
}
wrapWord(rows, word, columns);
continue;
}
if (rowLength + lengths[index] > columns && rowLength > 0 && lengths[index] > 0) {
if (options.wordWrap === false && rowLength < columns) {
wrapWord(rows, word, columns);
continue;
}
rows.push('');
}
if (rowLength + lengths[index] > columns && options.wordWrap === false) {
wrapWord(rows, word, columns);
continue;
}
rows[rows.length - 1] += word;
}
if (options.trim !== false) {
rows = rows.map(stringVisibleTrimSpacesRight);
}
pre = rows.join('\n');
for (const [index, character] of [...pre].entries()) {
ret += character;
if (ESCAPES.has(character)) {
const code = parseFloat(/\d[^m]*/.exec(pre.slice(index, index + 4)));
escapeCode = code === END_CODE ? null : code;
}
const code = ansiStyles.codes.get(Number(escapeCode));
if (escapeCode && code) {
if (pre[index + 1] === '\n') {
ret += wrapAnsi(code);
} else if (character === '\n') {
ret += wrapAnsi(escapeCode);
}
}
}
return ret;
};
// For each newline, invoke the method separately
module.exports = (string, columns, options) => {
return String(string)
.normalize()
.split('\n')
.map(line => exec(line, columns, options))
.join('\n');
};