internal/baseIsEqual.js

import baseIsEqualDeep from './baseIsEqualDeep';

/**
 * The base implementation of `_.isEqual` without support for `this` binding
 * `customizer` functions.
 *
 * @private
 * @param {*} value The value to compare.
 * @param {*} other The other value to compare.
 * @param {Function} [customizer] The function to customize comparing values.
 * @param {boolean} [isWhere] Specify performing partial comparisons.
 * @param {Array} [stackA] Tracks traversed `value` objects.
 * @param {Array} [stackB] Tracks traversed `other` objects.
 * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
 */
function baseIsEqual(value, other, customizer, isWhere, stackA, stackB) {
  // Exit early for identical values.
  if (value === other) {
    // Treat `+0` vs. `-0` as not equal.
    return value !== 0 || (1 / value == 1 / other);
  }
  var valType = typeof value,
      othType = typeof other;

  // Exit early for unlike primitive values.
  if ((valType != 'function' && valType != 'object' && othType != 'function' && othType != 'object') ||
      value == null || other == null) {
    // Return `false` unless both values are `NaN`.
    return value !== value && other !== other;
  }
  return baseIsEqualDeep(value, other, baseIsEqual, customizer, isWhere, stackA, stackB);
}

export default baseIsEqual;