When I call the following function, waitForSelector passes for 'selector', but assertExists fails for the same selector. How is it possible?
casper.waitForSelector(selector, function() {
casper.test.assertExists(selector, sectionName + " opened up successfully.");
}, function() {
casper.test.fail(sectionName + " did not load in given time");
}, max_timeout);
Here is a complete example to reproduce the issue with an :nth-child selector.
This is a known bug (see #11632, #11737) in the Qt4 fork of WebKit (from 2010). It happens when :nth-child() or :nth-of-type() CSS3 selectors are used. The second time the selector is run, it returns a different result (most of the time null). The only known workaround is to use XPath expressions instead of CSS3 selectors. This bug is fixed in PhantomJS 2 as it uses a Qt5 fork of WebKit (version 538.1).
This is a minimal script to reproduce the issue on http://example.com (modified from here):
var casper = require('casper').create(),
x = require('casper').selectXPath;
casper.start('http://example.com', function() {
var selector = 'p:nth-child(3) > a',
xpSelector = '//*[local-name()="p" and position()=3]/a';
var first = this.exists(selector);
var second = this.exists(selector);
if(first !== second) {
console.error('Expected First selector to equal the Second');
} else {
console.log('Passed');
}
first = this.exists(x(xpSelector));
second = this.exists(x(xpSelector));
if(first !== second) {
console.error('Expected First selector to equal the Second');
} else {
console.log('Passed');
}
}).run();
Output:
Expected First selector to equal the Second Passed
Markup is:
<div>
<h1>text</h1>
<p>text</p>
<p><a href="url">text</a></p>
</div>
The XPath expression looks a little awkward, because it directly reproduces the intended behavior of the CSS selector. Normally one would write //p[2]/a.
