Test drive 104 new Professional-grade tests for web standards

March 18th, 2010

The Windows Internet Explorer Platform Preview build marks an important milestone in the development of the next version of Internet Explorer. A significant part of the platform preview is focused on new or proposed World Wide Web Consortium (W3C) web standards.

The goal of industry standards is actually “interoperability.” For HD television standards, that means that multiple TVs can render the same rich content in a consistent way. In the web case, that means the same HTML, script, and formatting markup work the same across different browsers. Eliminating the need for different code paths for different browsers benefits everyone, and creates more opportunity for developers to innovate on great web content.

Developers have said they want to use the same markup across all modern browsers. Each proposed standard needs a comprehensive test suite to make this happen. The test suite helps resolve ambiguities in the specification by testing any implementation (aka browser) built on that specification.

The test suites also need to thoroughly exercise everything in the specification and not just test a handful of things sampled from various parts of the spec. During the IE8 project we submitted 7201 test cases to the W3C’s CSS 2.1 Working Group in an effort to help the industry develop a comprehensive test of the CSS 2.1 specification. It was exciting to see other companies join in and provide additional cases as well. As a result, the count of CSS 2.1 test cases grew to 8777 as it moved from pre-alpha to Alpha on January 27th, 2010. This will help every browser vendor build a more consistently behaving browser on which web developers can finally start to depend.

As we look through the test suites for other web standards working groups, we’re finding areas in which there is a need for more thorough testing. As a result, we’re expanding the working groups into which Microsoft is submitting test cases. We also listened to feedback about the volume of test cases and the frequency in which we submit them to the working groups. In conjunction with our first preview release, we’re submitting 104 test cases across six different proposed or recommended web standards. These include:


Number of new cases submitted by Microsoft

Test Suite

Test Case Feedback Link

Scalable Vector Graphics (SVG) 1.1 (2nd Edition)


SVG Test Suite

Test Review Wiki

CSS3 Backgrounds and Borders


CSS 3 Backgrounds and Borders Test Suite (no suite yet)

CSS test suite mailing list

CSS3 Selectors


CSS3 Selectors Test Suite

CSS test suite mailing list

DOM Level 2 Core


DOM L2 Core Test Suite

DOM Mail Archives

DOM Level 3 Events


DOM L3 Events Test Suite

DOM Mail Archives

DOM Level 2 Style


DOM L2 Core Test Suite

DOM Mail Archives




Until these all make it through the W3C test publishing process, you can find the cases on the Internet Explorer Testing Center.

I want to thank the members in the W3C working groups that helped us develop these tests, the community members for providing valuable feedback on the tests, as well as the engineers on the IE team that made these possible.

Jason Upton
Test Manager, Internet Explorer