puppeteer/lib/helper.js
Andrey Lushnikov e6af6e19d6 feat(console): dispatch JSHandles as console arguments (#975)
This patch starts dispatching JSHandle instances as console arguments.

BREAKING CHANGE: this changes the API of the ConsoleMessage.

Fixes #324.
2017-10-09 17:01:01 -07:00

219 lines
6.8 KiB
JavaScript

/**
* Copyright 2017 Google Inc. All rights reserved.
*
* 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.
*/
const debugError = require('debug')(`puppeteer:error`);
/** @type {?Map<string, boolean>} */
let apiCoverage = null;
class Helper {
/**
* @param {function()|string} fun
* @param {!Array<*>} args
* @return {string}
*/
static evaluationString(fun, ...args) {
if (Helper.isString(fun)) {
console.assert(args.length === 0, 'Cannot evaluate a string with arguments');
return fun;
}
return `(${fun})(${args.map(serializeArgument).join(',')})`;
/**
* @param {*} arg
* @return {string}
*/
function serializeArgument(arg) {
if (Object.is(arg, undefined))
return 'undefined';
return JSON.stringify(arg);
}
}
/**
* @param {!Object} exceptionDetails
* @return {string}
*/
static getExceptionMessage(exceptionDetails) {
if (exceptionDetails.exception)
return exceptionDetails.exception.description;
let message = exceptionDetails.text;
if (exceptionDetails.stackTrace) {
for (const callframe of exceptionDetails.stackTrace.callFrames) {
const location = callframe.url + ':' + callframe.lineNumber + ':' + callframe.columnNumber;
const functionName = callframe.functionName || '<anonymous>';
message += `\n at ${functionName} (${location})`;
}
}
return message;
}
/**
* @param {!Session} client
* @param {!Object} remoteObject
* @return {!Promise<!Object>}
*/
static valueFromRemoteObject(remoteObject) {
console.assert(!remoteObject.objectId, 'Cannot extract value when objectId is given');
if (remoteObject.unserializableValue) {
switch (remoteObject.unserializableValue) {
case '-0':
return -0;
case 'NaN':
return NaN;
case 'Infinity':
return Infinity;
case '-Infinity':
return -Infinity;
default:
throw new Error('Unsupported unserializable value: ' + remoteObject.unserializableValue);
}
}
return remoteObject.value;
}
/**
* @param {!Session} client
* @param {!Object} remoteObject
*/
static async releaseObject(client, remoteObject) {
if (!remoteObject.objectId)
return;
await client.send('Runtime.releaseObject', {objectId: remoteObject.objectId}).catch(error => {
// Exceptions might happen in case of a page been navigated or closed.
// Swallow these since they are harmless and we don't leak anything in this case.
debugError(error);
});
}
/**
* @param {!Object} classType
*/
static tracePublicAPI(classType) {
let className = classType.prototype.constructor.name;
className = className.substring(0, 1).toLowerCase() + className.substring(1);
const debug = require('debug')(`puppeteer:${className}`);
if (!debug.enabled && !apiCoverage)
return;
for (const methodName of Reflect.ownKeys(classType.prototype)) {
const method = Reflect.get(classType.prototype, methodName);
if (methodName === 'constructor' || typeof methodName !== 'string' || methodName.startsWith('_') || typeof method !== 'function')
continue;
if (apiCoverage)
apiCoverage.set(`${className}.${methodName}`, false);
Reflect.set(classType.prototype, methodName, function(...args) {
const argsText = args.map(stringifyArgument).join(', ');
const callsite = `${className}.${methodName}(${argsText})`;
if (debug.enabled)
debug(callsite);
if (apiCoverage)
apiCoverage.set(`${className}.${methodName}`, true);
return method.call(this, ...args);
});
}
if (classType.Events) {
if (apiCoverage) {
for (const event of Object.values(classType.Events))
apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, false);
}
const method = Reflect.get(classType.prototype, 'emit');
Reflect.set(classType.prototype, 'emit', function(event, ...args) {
const argsText = [JSON.stringify(event)].concat(args.map(stringifyArgument)).join(', ');
if (debug.enabled && this.listenerCount(event))
debug(`${className}.emit(${argsText})`);
if (apiCoverage && this.listenerCount(event))
apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, true);
return method.call(this, event, ...args);
});
}
/**
* @param {!Object} arg
* @return {string}
*/
function stringifyArgument(arg) {
if (Helper.isString(arg) || Helper.isNumber(arg) || !arg)
return JSON.stringify(arg);
if (typeof arg === 'function') {
let text = arg.toString().split('\n').map(line => line.trim()).join('');
if (text.length > 20)
text = text.substring(0, 20) + '…';
return `"${text}"`;
}
const state = {};
const keys = Object.keys(arg);
for (const key of keys) {
const value = arg[key];
if (Helper.isString(value) || Helper.isNumber(value))
state[key] = JSON.stringify(value);
}
const name = arg.constructor.name === 'Object' ? '' : arg.constructor.name;
return name + JSON.stringify(state);
}
}
/**
* @param {!EventEmitter} emitter
* @param {string} eventName
* @param {function(?)} handler
* @return {{emitter: !EventEmitter, eventName: string, handler: function(?)}}
*/
static addEventListener(emitter, eventName, handler) {
emitter.on(eventName, handler);
return { emitter, eventName, handler };
}
/**
* @param {!Array<{emitter: !EventEmitter, eventName: string, handler: function(?)}>}
*/
static removeEventListeners(listeners) {
for (const listener of listeners)
listener.emitter.removeListener(listener.eventName, listener.handler);
listeners.splice(0, listeners.length);
}
/**
* @return {?Map<string, boolean>}
*/
static publicAPICoverage() {
return apiCoverage;
}
static recordPublicAPICoverage() {
apiCoverage = new Map();
}
/**
* @param {!Object} obj
* @return {boolean}
*/
static isString(obj) {
return typeof obj === 'string' || obj instanceof String;
}
/**
* @param {!Object} obj
* @return {boolean}
*/
static isNumber(obj) {
return typeof obj === 'number' || obj instanceof Number;
}
}
module.exports = {
helper: Helper,
debugError
};