lodash/_baseConforms.js

define(['./keys'], function(keys) {

  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
  var undefined;

  /**
   * The base implementation of `_.conforms` which doesn't clone `source`.
   *
   * @private
   * @param {Object} source The object of property predicates to conform to.
   * @returns {Function} Returns the new function.
   */
  function baseConforms(source) {
    var props = keys(source),
        length = props.length;

    return function(object) {
      if (object == null) {
        return !length;
      }
      var index = length;
      while (index--) {
        var key = props[index],
            predicate = source[key],
            value = object[key];

        if ((value === undefined &&
            !(key in Object(object))) || !predicate(value)) {
          return false;
        }
      }
      return true;
    };
  }

  return baseConforms;
});