This page has been deprecated and is no longer being maintained.
For up to date information on contributing and authoring CSS Test suites, see:
http://testthewebforward.org/docs/test-style-guidelines.html#self-describing-tests </strong>
</html> # Self-Describing Tests A self-describing test is a test page that describes what the page should look like when the test has passed. A human examining the test page can then determine from the description whether the test has passed or failed. > [!NOTE] > The following are some examples of self-describing tests, using common techniques to identify passes: > > * [Identical Renderings](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/escapes-000.htm) > * [Green Background](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/escapes-002.htm) > * [No Red 1](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/abspos-containing-block-003.htm) > * [No Red 2](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/border-conflict-w-079.htm) > * [Described Alignment](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/margin-collapse-clear-007.htm) > * [Overlapping](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/table-anonymous-objects-021.htm) > * [Imprecise Description 1](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/border-style-inset-001.htm) > * [Imprecise Description 2](http://www.w3.org/Style/CSS/Test/CSS2.1/20100127/html4/text-decoration-001.htm) Self-describing tests have some advantages: - They can be run easily on any layout engine. - They can test areas of the spec that are not precise enough to be comparable to a reference rendering. (For example, underlining cannot be compared to a reference because the position and thickness of the underline is UA-dependent.) - Failures can (should) be easily determined by a human viewing the test without needing special tools. They also have some disadvantages: - They cannot be automated: a human must determine whether the test has passed or failed. - In some cases it is difficult or impossible to design the test for a glaringly obvious pass or fail. (In these cases, if it's possible to create a reference, the [reftest](/test/reftest/) format may be more appropriate.) Self-describing tests must follow the [CSS test format guidelines](/format/). Additional information on writing self-describing tests is available [on the W3C site](http://www.w3.org/Style/CSS/Test/guidelines.html).