我可以针对localhost运行我的量角器测试，但是当我点击我的内部测试服务器时，我无法让量角器在页面上找到元素。使用最新的Chrome和Firefox驱动程序时，Protractor 1.3.1和1.4.0也会出现同样的问题。
...AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\atoms\error.js:113
var template = new Error(this.message);
^
Process finished with exit code 1
所以我一直在尝试使用Element explorer来调试问题，但它给了我以下内容：
> list(by.css('#logindropdown'))
There was a webdriver error: UnknownError unknown error: Runtime.evaluate threw exception: TypeError: Cannot read property 'click' of null
(Session info: chrome=38.0.2125.111)
(Driver info: chromedriver=2.12.301325 (962dea43ddd90e7e4224a03fa3c36a421281abb7),platform=Windows NT 6.1 SP1 x86_64) (WARNING: The server did not provide any stacktrace information)
Command duration or timeout: 28 milliseconds
Build info: version: '2.44.0', revision: '76d78cf', time: '2014-10-23 20:02:37'
System info: host: 'NB2D1469', ip: '158.147.71.49', os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_67'
Session ID: 85966371ff89f75af8cf7fb5d15f6f23
Driver info: org.openqa.selenium.chrome.ChromeDriver
Capabilities [{platform=XP, acceptSslCerts=true, javascriptEnabled=true, browserName=chrome, chrome={userDataDir=C:\Users\mprent99\AppData\Local\Temp\scoped_dir6488_12276}, rotatable=false, locationContextEnabled=true, mobileEmulationEnabled=false, version=38.0
.2125.111, takesHeapSnapshot=true, cssSelectorsEnabled=true, databaseEnabled=false, handlesAlerts=true, browserConnectionEnabled=false, webStorageEnabled=true, nativeEvents=true, applicationCacheEnabled=false, takesScreenshot=true}]
像list(by.css('body'))这样的简单事情也会给出相同的例外情况。使用by.id会得到相同的结果list(by.id('logindropdown'))
没有结果的命令（当它们应该的时候）似乎避免了例外：
> list(by.css('a .caret'))
[ '' ]
> list(by.css('.caret'))
[ '' ]
在webdriver-manager终端中，我看到以下内容：
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:204)
at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:156)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:599)
at org.openqa.selenium.remote.RemoteWebDriver.executeAsyncScript(RemoteWebDriver.java:526)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.openqa.selenium.support.events.EventFiringWebDriver$2.invoke(EventFiringWebDriver.java:101)
at com.sun.proxy.$Proxy1.executeAsyncScript(Unknown Source)
at org.openqa.selenium.support.events.EventFiringWebDriver.executeAsyncScript(EventFiringWebDriver.java:225)
at org.openqa.selenium.remote.server.handler.ExecuteAsyncScript.call(ExecuteAsyncScript.java:55)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at org.openqa.selenium.remote.server.DefaultSession$1.run(DefaultSession.java:168)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
和
17:05:00.256 INFO - Executing: [execute async script: try { return (function (rootSelector, callback) {
var el = document.querySelector(rootSelector);
try {
if (angular.getTestability) {
angular.getTestability(el).whenStable(callback);
} else {
angular.element(el).injector().get('$browser').
notifyWhenNoOutstandingRequests(callback);
}
} catch (e) {
callback(e);
}
}).apply(this, arguments); }
catch(e) { throw (e instanceof Error) ? e : new Error(e); }, [body]])
17:05:00.562 WARN - Exception thrown
org.openqa.selenium.WebDriverException: unknown error: Runtime.evaluate threw exception: TypeError: Cannot read property 'click' of null
正在使用的版本：
protractor --version
Version 1.4.0 or Version 1.3.1
node --version
v0.10.30
webdriver-manager status
selenium standalone is up to date
chromedriver is up to date
IEDriver is not present
这些相同的东西在Chrome DevTools中运行得很好：
('.caret')
[<b class="caret"></b>]
$('a .caret')
[<b class="caret"></b>]
$('#logindropdown')
[<li id="logindropdown" class="dropdown ng-scope">…</li>]
$('body')
[<body class="vertical-grow">…</body>]
这是发生故障的onPrepare：
onPrepare: function() {
var username = element(by.model('login.userName'));
var password = element(by.model('login.password'));
browser.driver.get(env.baseUrl);
browser.driver.findElement(by.css('a .caret')).click();
username.sendKeys('user@company.com');
password.sendKeys('password');
browser.driver.findElement(by.css('.btn-primary')).click();
// Login takes some time, so wait until it's done.
// For the test app's login, we know it's done when it redirects to index.html.
browser.driver.wait(function() {
return browser.driver.getCurrentUrl().then(function(url) {
return (/dashboards/).test(url);
});
}, 5000);
}
这是其余的conf.js：
/*global browser,element,by */
var env = require('./env.js');
exports.config = {
seleniumAddress: 'http://localhost:4444/wd/hub',
specs: [
'loginTest.js'
],
suites: {
//smoke: 'spec/smoketests/*.js',
//full: 'spec/*.js'
},
directConnect: false,
multiCapabilities: [
// {browserName: 'firefox'}
{browserName: 'chrome'}
],
maxSessions: -1,
framework: 'jasmine',
// Options to be passed to Jasmine-node.
jasmineNodeOpts: {
// If true, display spec names.
isVerbose: false,
// If true, print colors to the terminal.
showColors: true,
// If true, include stack traces in failures.
includeStackTrace: true,
// Default time to wait in ms before a test fails.
defaultTimeoutInterval: 360000
},
// Selector for the element housing the angular app - this defaults to
// body, but is necessary if ng-app is on a descendant of <body>
rootElement: 'html'
};
如何进一步调试并找到此问题的根源？