33 lines
975 B
JavaScript
33 lines
975 B
JavaScript
'use strict';
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var bind = require('function-bind');
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var ES = require('es-abstract/es7');
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var slice = bind.call(Function.call, String.prototype.slice);
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module.exports = function padStart(maxLength) {
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var O = ES.RequireObjectCoercible(this);
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var S = ES.ToString(O);
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var stringLength = ES.ToLength(S.length);
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var fillString;
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if (arguments.length > 1) {
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fillString = arguments[1];
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}
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var filler = typeof fillString === 'undefined' ? '' : ES.ToString(fillString);
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if (filler === '') {
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filler = ' ';
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}
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var intMaxLength = ES.ToLength(maxLength);
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if (intMaxLength <= stringLength) {
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return S;
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}
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var fillLen = intMaxLength - stringLength;
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while (filler.length < fillLen) {
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var fLen = filler.length;
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var remainingCodeUnits = fillLen - fLen;
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filler += fLen > remainingCodeUnits ? slice(filler, 0, remainingCodeUnits) : filler;
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}
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var truncatedStringFiller = filler.length > fillLen ? slice(filler, 0, fillLen) : filler;
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return truncatedStringFiller + S;
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};
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