node-lodash-packages 4.15.0-1 / usr / lib / nodejs / lodash.lowerfirst / index.js

/**
 * lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * Copyright jQuery Foundation and other contributors <https://jquery.org/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */

/** Used as references for various `Number` constants. */
var INFINITY = 1 / 0;

/** `Object#toString` result references. */
var symbolTag = '[object Symbol]';

/** Used to compose unicode character classes. */
var rsAstralRange = '\\ud800-\\udfff',
    rsComboMarksRange = '\\u0300-\\u036f\\ufe20-\\ufe23',
    rsComboSymbolsRange = '\\u20d0-\\u20f0',
    rsVarRange = '\\ufe0e\\ufe0f';

/** Used to compose unicode capture groups. */
var rsAstral = '[' + rsAstralRange + ']',
    rsCombo = '[' + rsComboMarksRange + rsComboSymbolsRange + ']',
    rsFitz = '\\ud83c[\\udffb-\\udfff]',
    rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')',
    rsNonAstral = '[^' + rsAstralRange + ']',
    rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}',
    rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]',
    rsZWJ = '\\u200d';

/** Used to compose unicode regexes. */
var reOptMod = rsModifier + '?',
    rsOptVar = '[' + rsVarRange + ']?',
    rsOptJoin = '(?:' + rsZWJ + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*',
    rsSeq = rsOptVar + reOptMod + rsOptJoin,
    rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')';

/** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */
var reUnicode = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g');

/** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */
var reHasUnicode = RegExp('[' + rsZWJ + rsAstralRange  + rsComboMarksRange + rsComboSymbolsRange + rsVarRange + ']');

/** Detect free variable `global` from Node.js. */
var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;

/** Detect free variable `self`. */
var freeSelf = typeof self == 'object' && self && self.Object === Object && self;

/** Used as a reference to the global object. */
var root = freeGlobal || freeSelf || Function('return this')();

/**
 * Converts an ASCII `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function asciiToArray(string) {
  return string.split('');
}

/**
 * Checks if `string` contains Unicode symbols.
 *
 * @private
 * @param {string} string The string to inspect.
 * @returns {boolean} Returns `true` if a symbol is found, else `false`.
 */
function hasUnicode(string) {
  return reHasUnicode.test(string);
}

/**
 * Converts `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function stringToArray(string) {
  return hasUnicode(string)
    ? unicodeToArray(string)
    : asciiToArray(string);
}

/**
 * Converts a Unicode `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function unicodeToArray(string) {
  return string.match(reUnicode) || [];
}

/** Used for built-in method references. */
var objectProto = Object.prototype;

/**
 * Used to resolve the
 * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
 * of values.
 */
var objectToString = objectProto.toString;

/** Built-in value references. */
var Symbol = root.Symbol;

/** Used to convert symbols to primitives and strings. */
var symbolProto = Symbol ? Symbol.prototype : undefined,
    symbolToString = symbolProto ? symbolProto.toString : undefined;

/**
 * The base implementation of `_.slice` without an iteratee call guard.
 *
 * @private
 * @param {Array} array The array to slice.
 * @param {number} [start=0] The start position.
 * @param {number} [end=array.length] The end position.
 * @returns {Array} Returns the slice of `array`.
 */
function baseSlice(array, start, end) {
  var index = -1,
      length = array.length;

  if (start < 0) {
    start = -start > length ? 0 : (length + start);
  }
  end = end > length ? length : end;
  if (end < 0) {
    end += length;
  }
  length = start > end ? 0 : ((end - start) >>> 0);
  start >>>= 0;

  var result = Array(length);
  while (++index < length) {
    result[index] = array[index + start];
  }
  return result;
}

/**
 * The base implementation of `_.toString` which doesn't convert nullish
 * values to empty strings.
 *
 * @private
 * @param {*} value The value to process.
 * @returns {string} Returns the string.
 */
function baseToString(value) {
  // Exit early for strings to avoid a performance hit in some environments.
  if (typeof value == 'string') {
    return value;
  }
  if (isSymbol(value)) {
    return symbolToString ? symbolToString.call(value) : '';
  }
  var result = (value + '');
  return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
}

/**
 * Casts `array` to a slice if it's needed.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {number} start The start position.
 * @param {number} [end=array.length] The end position.
 * @returns {Array} Returns the cast slice.
 */
function castSlice(array, start, end) {
  var length = array.length;
  end = end === undefined ? length : end;
  return (!start && end >= length) ? array : baseSlice(array, start, end);
}

/**
 * Creates a function like `_.lowerFirst`.
 *
 * @private
 * @param {string} methodName The name of the `String` case method to use.
 * @returns {Function} Returns the new case function.
 */
function createCaseFirst(methodName) {
  return function(string) {
    string = toString(string);

    var strSymbols = hasUnicode(string)
      ? stringToArray(string)
      : undefined;

    var chr = strSymbols
      ? strSymbols[0]
      : string.charAt(0);

    var trailing = strSymbols
      ? castSlice(strSymbols, 1).join('')
      : string.slice(1);

    return chr[methodName]() + trailing;
  };
}

/**
 * Checks if `value` is object-like. A value is object-like if it's not `null`
 * and has a `typeof` result of "object".
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
 * @example
 *
 * _.isObjectLike({});
 * // => true
 *
 * _.isObjectLike([1, 2, 3]);
 * // => true
 *
 * _.isObjectLike(_.noop);
 * // => false
 *
 * _.isObjectLike(null);
 * // => false
 */
function isObjectLike(value) {
  return !!value && typeof value == 'object';
}

/**
 * Checks if `value` is classified as a `Symbol` primitive or object.
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
 * @example
 *
 * _.isSymbol(Symbol.iterator);
 * // => true
 *
 * _.isSymbol('abc');
 * // => false
 */
function isSymbol(value) {
  return typeof value == 'symbol' ||
    (isObjectLike(value) && objectToString.call(value) == symbolTag);
}

/**
 * Converts `value` to a string. An empty string is returned for `null`
 * and `undefined` values. The sign of `-0` is preserved.
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Lang
 * @param {*} value The value to process.
 * @returns {string} Returns the string.
 * @example
 *
 * _.toString(null);
 * // => ''
 *
 * _.toString(-0);
 * // => '-0'
 *
 * _.toString([1, 2, 3]);
 * // => '1,2,3'
 */
function toString(value) {
  return value == null ? '' : baseToString(value);
}

/**
 * Converts the first character of `string` to lower case.
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category String
 * @param {string} [string=''] The string to convert.
 * @returns {string} Returns the converted string.
 * @example
 *
 * _.lowerFirst('Fred');
 * // => 'fred'
 *
 * _.lowerFirst('FRED');
 * // => 'fRED'
 */
var lowerFirst = createCaseFirst('toLowerCase');

module.exports = lowerFirst;