BidiChecker is a tool for the automated testing of web pages for errors in support of right-to-left (RTL) languages, also known as bidirectional (bidi) because they routinely include left-to-right items such as numbers and Latin-script words and phrases.
Bidi support for a web page is a common requirement, even for pages in left-to-right scripts. Any page which accepts user input or displays multilingual content is likely to end up handling bidirectional text at some point, as it will eventually encounter data in Arabic, Hebrew or another RTL language. Unfortunately, handling bidirectional text can be tricky and requires special processing at every appearance of potentially bidi data in the UI. (Examples of common bidi UI bugs can be found here.) As a result, bidi text support often regresses when a developer adds a new feature and simply forgets about bidi.
For exploratory testing, you can also run BidiChecker manually by installing this handy bookmarklet in your browser.
Using BidiChecker does not require any custom "hooks" or modifications to the product under test. New BidiChecker-based tests can be written in addition to the product's existing test suite.