Firefox Add-On Test Tools: Page Validator and Link Evaluator

There are a number of Firefox add-ons that can assist you when testing web sites. I've reviewed several of the most popular ones and will tell you about them in this and upcoming articles. This week I've taken a look at two FireFox add-on tools, Page Validator and Link Evaluator. These tools offer a convenient and easy way to provide additional coverage for each web page you test. And if you're looking to find and report additional bugs during your functional testing, these tools may be just what you're looking for.

Both of these tools take a look "behind the scenes" at the underlying HTML of each web page displayed in the Firefox browser. And both provide a valuable assessment of the format and integrity of the web pages you test.

Page Validator validates a page using the W3C Markup Validation Service. The most compelling reason to test web pages to conform to the W3C validation rule-set is because "validation is one of the simplest ways to check whether a page is built in accordance with Web standards, and provides one of the most reliable guarantee that future Web platforms will handle it as designed." In other words, you do this to "future proof" your web pages. From a tester's perspective, you are providing information to the developer and management as to how well each web page conforms to W3C standards so that they can understand why, in some browsers, your web page may not be rendering as expected. Recommendation: before you report all the errors that this FireFox add-on reports, become familiar with the W3C Validation Service FAQs and be sure you understand what the errors mean before reporting them.

Link Evaluator is just as easy to use and as effective as Page Validator. It works as an enhanced Link Checker - both for the links on the current Web page and for any Bookmarked links. It examines both the HTTP status code and the page contents returned by each URL, and attempts to distinguish between various results, such as broken links, network time-outs, authentication failure, and 'incorrect/correct' content for the given URL.

I ran Link Evaluator on the first page of the Testlabs.com blog. After each link was checked, Link Evaluator highlighted them with a color indicating the test "score": green for full success, yellow for part, and red for no success. Rollover text was added to each link, noting the HTTP status returned, e.g. 200 - OK. I did get some yellow colored links that did not seem to have any problems. I would be careful reporting "yellow" links without investigating them further to find the exact reason they were scored as only partially successful.

I strongly recommend installing these tools in your FireFox browser whenever doing compatibility testing - I guarantee you that you will find some additional bugs to report. You can download and install Page Validator here and Link Evaluator here.