xml - Using XPATH to search text containing  

Question

I use XPather Browser to check my XPATH expressions on an HTML page.

My end goal is to use these expressions in Selenium for the testing of my user interfaces.

I got an HTML file with a content similar to this:

<tr>
  <td>abc</td>
  <td>&nbsp;</td>
</tr>

I want to select a node with a text containing the string " ".

With a normal string like "abc" there is no problem. I use an XPATH similar to //td[text()="abc"].

When I try with an an XPATH like //td[text()=" "] it returns nothing. Is there a special rule concerning texts with "&" ?

Answer 1

It seems that OpenQA, guys behind Selenium, have already addressed this problem. They defined some variables to explicitely match whitespaces. In my case, I need to use an XPATH similar to //td[text()="${nbsp}"].

I reproduced here the text from OpenQA concerning this issue (found here):

HTML automatically normalizes whitespace within elements, ignoring leading/trailing spaces and converting extra spaces, tabs and newlines into a single space. When Selenium reads text out of the page, it attempts to duplicate this behavior, so you can ignore all the tabs and newlines in your HTML and do assertions based on how the text looks in the browser when rendered. We do this by replacing all non-visible whitespace (including the non-breaking space " ") with a single space. All visible newlines (<br>, <p>, and <pre> formatted new lines) should be preserved.

We use the same normalization logic on the text of HTML Selenese test case tables. This has a number of advantages. First, you don't need to look at the HTML source of the page to figure out what your assertions should be; " " symbols are invisible to the end user, and so you shouldn't have to worry about them when writing Selenese tests. (You don't need to put " " markers in your test case to assertText on a field that contains " ".) You may also put extra newlines and spaces in your Selenese <td> tags; since we use the same normalization logic on the test case as we do on the text, we can ensure that assertions and the extracted text will match exactly.

This creates a bit of a problem on those rare occasions when you really want/need to insert extra whitespace in your test case. For example, you may need to type text in a field like this: "foo ". But if you simply write <td>foo </td> in your Selenese test case, we'll replace your extra spaces with just one space.

This problem has a simple workaround. We've defined a variable in Selenese, ${space}, whose value is a single space. You can use ${space} to insert a space that won't be automatically trimmed, like this: <td>foo${space}${space}${space}</td>. We've also included a variable ${nbsp}, that you can use to insert a non-breaking space.

Note that XPaths do not normalize whitespace the way we do. If you need to write an XPath like //div[text()="hello world"] but the HTML of the link is really "hello world", you'll need to insert a real " " into your Selenese test case to get it to match, like this: //div[text()="hello${nbsp}world"].