lodash/lodash._createpad/index.js

/**
 * lodash 3.0.0 (Custom Build) <https://lodash.com/>
 * Build: `lodash modern modularize exports="npm" -o ./`
 * Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
 * Based on Underscore.js 1.7.0 <http://underscorejs.org/LICENSE>
 * Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 * Available under MIT license <https://lodash.com/license>
 */
var repeat = require('lodash.repeat');

/**
 * Converts `value` to a string if it is not one. An empty string is returned
 * for `null` or `undefined` values.
 *
 * @private
 * @param {*} value The value to process.
 * @returns {string} Returns the string.
 */
function baseToString(value) {
  if (typeof value == 'string') {
    return value;
  }
  return value == null ? '' : (value + '');
}

/** Native method references. */
var ceil = Math.ceil;

/* Native method references for those with the same name as other `lodash` methods. */
var nativeIsFinite = global.isFinite;

/**
 * Creates the pad required for `string` based on the given padding length.
 * The `chars` string may be truncated if the number of padding characters
 * exceeds the padding length.
 *
 * @private
 * @param {string} string The string to create padding for.
 * @param {number} [length=0] The padding length.
 * @param {string} [chars=' '] The string used as padding.
 * @returns {string} Returns the pad for `string`.
 */
function createPad(string, length, chars) {
  var strLength = string.length;
  length = +length;

  if (strLength >= length || !nativeIsFinite(length)) {
    return '';
  }
  var padLength = length - strLength;
  chars = chars == null ? ' ' : baseToString(chars);
  return repeat(chars, ceil(padLength / chars.length)).slice(0, padLength);
}

module.exports = createPad;