com.google.javascript.jscomp.js.es6_dart_runtime.js Maven / Gradle / Ivy
/*
* Copyright 2014 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @fileoverview Additional runtime functions required for transpilation from
* ES6 to ES5 of code generated by the Dart Dev Compiler.
*
* Note that DDC's output cannot currently be lowered to ES3 (heavy use of
* getters or setters, including in the runtime), so these helpers make no
* attempt of fallback behaviour when methods like Object.getPrototypeOf or
* Object.getOwnPropertyDescriptor are undefined (unlike helpers in es6/*.js).
*/
'require base';
/**
* Gets a property descriptor for a target instance, skipping its class
* and walking up the super-classes hierarchy.
*
* @private
* @param {!Object} target
* @param {!string} name
* @return {?}
*/
$jscomp.getSuperPropertyDescriptor_ = function(target, name) {
var getPrototypeOf = Object.getPrototypeOf;
var getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;
var cls = getPrototypeOf(target);
while (cls != null) {
cls = getPrototypeOf(cls);
if (cls != null) {
var desc = getOwnPropertyDescriptor(cls, name);
if (desc != null) {
return desc;
}
}
}
return undefined;
};
/**
* Gets a property of a target instance using its super class getter or value,
* or returns undefined if that property is not defined on any ancestor.
*
* @param {!Object} target
* @param {!string} propertyName
* @return {*}
*/
$jscomp.superGet = function(target, propertyName) {
var desc = $jscomp.getSuperPropertyDescriptor_(target, propertyName);
return desc && (desc.get ? desc.get.call(target) : desc.value);
};
/**
* Sets a property on a target instance using its super setter if is defined
* on any ancestor, or setting it as a simple property on the target otherwise.
*
* @template T
* @param {!Object} target
* @param {!string} propertyName
* @param {T} value
* @return {T}
*/
$jscomp.superSet = function(target, propertyName, value) {
var desc = $jscomp.getSuperPropertyDescriptor_(target, propertyName);
if (desc) {
if (!desc.set) {
throw new TypeError('No setter for super.' + propertyName);
}
desc.set.call(target, value);
} else {
target[propertyName] = value;
}
return value;
};