我正在使用
Java / Selenium测试
JavaScript API.
我在Java端发出这些命令,
executor.executeScript("setName('Hello');");
// Thread.sleep(2000);
String output = (String)executor.executeScript("return getName()");
assertEquals(output,"Hello");
在JavaScript方面,这是一个异步函数,因此它需要一些时间并设置变量.
function setName(msg) {
// simulate async call
setName(function(){name = msg;},1000);
}
我需要等待这个异步函数完成,然后再转到Java中的下一行,执行assertEquals().
如果不在Java端使用Thread.sleep(),有没有办法实现这一点.
谢谢
解决方法
您可以轻松地要求Selenium等到特定条件成立;在你拥有的,一个替代方案是：
new FluentWait<JavascriptExecutor>(executor) {
protected RuntimeException timeoutException(
String message,Throwable lastException) {
Assert.fail("name was never set");
}
}.withTimeout(10,SECONDS)
.until(new Predicate<JavascriptExecutor>() {
public boolean apply(JavascriptExecutor e) {
return (Boolean)executor.executeScript("return ('Hello' === getName());");
}
});
但是,那么你基本上测试的是你刚刚编写的内容,并且缺点是如果在调用setName之前设置了name,则不必等待setName完成.我过去做过类似事情的一件事是：
在我的测试库中(用setTimeout垫片替换真正的异步调用),我有这个：
window._junit_testid_ = '*none*';
window._junit_async_calls_ = {};
function _setJunitTestid_(testId) {
window._junit_testid_ = testId;
}
function _setTimeout_(cont,timeout) {
var callId = Math.random().toString(36).substr(2);
var testId = window._junit_testid_;
window._junit_async_calls_[testId] |= {};
window._junit_async_calls_[testId][callId] = 1;
window.setTimeout(function(){
cont();
delete(window._junit_async_calls_[testId][callId]);
},timeout);
}
function _isTestDone_(testId) {
if (window._junit_async_calls_[testId]) {
var thing = window._junit_async_calls_[testId];
for (var prop in thing) {
if (thing.hasOwnProperty(prop)) return false;
}
delete(window._junit_async_calls_[testId]);
}
return true;
}
在我的库的其余部分,每当我需要设置稍后发生的事情时,我使用_setTimeout_而不是window.setTimeout.然后,在我的硒测试中,我做了这样的事情：
// First,this routine is in a library somewhere
public void waitForTest(JavascriptExecutor executor,String testId) {
new FluentWait<JavascriptExecutor>(executor) {
protected RuntimeException timeoutException(
String message,Throwable lastException) {
Assert.fail(testId + " did not finish async calls");
}
}.withTimeout(10,SECONDS)
.until(new Predicate<JavascriptExecutor>() {
public boolean apply(JavascriptExecutor e) {
return (Boolean)executor.executeScript(
"_isTestDone_('" + testId + "');");
}
});
}
// Inside an actual test:
@Test public void serverPingTest() {
// Do stuff to grab my WebDriver instance
// Do this before any interaction with the app
driver.executeScript("_setJunitTestid_('MainAppTest.serverPingTest');");
// Do other stuff including things that fire off what would be async calls
// but now call stuff in my testing library instead.
// ...
// Now I need to wait for all the async stuff to finish:
waitForTest(driver,"MainAppTest.serverPingTest");
// Now query stuff about the app,assert things if needed
}
请注意,如果需要,您可以多次调用waitForTest,只要您需要该测试暂停,直到完成所有异步操作.
