/** Used for native method references. */
var objectProto = Object.prototype;

/** Used to check objects for own properties. */
var hasOwnProperty = objectProto.hasOwnProperty;

/**
 * Used by `_.template` to customize its `_.assign` use.
 *
 * **Note:** This function is like `assignDefaults` except that it ignores
 * inherited property values when checking if a property is `undefined`.
 *
 * @private
 * @param {*} objectValue The destination object property value.
 * @param {*} sourceValue The source object property value.
 * @param {string} key The key associated with the object and source values.
 * @param {Object} object The destination object.
 * @returns {*} Returns the value to assign to the destination object.
 */
function assignOwnDefaults(objectValue, sourceValue, key, object) {
  return (objectValue === undefined || !hasOwnProperty.call(object, key))
    ? sourceValue
    : objectValue;
}

module.exports = assignOwnDefaults;