NonDex

What NonDex is

NonDex is a free, MIT-licensed tool for finding Java tests that rely on one behavior even though an API specification permits several. It explores allowed behaviors in under-determined APIs to help expose implementation-dependent assumptions that can make tests flaky or cause portability bugs across Java runtime environments. The project supports JUnit and TestNG and provides Maven and Gradle plugins as well as command-line instructions. It reports tests that pass without shuffling but fail when behaviors are shuffled, and logs results in a `.nondex` directory. Debug tasks provide reproduction arguments and output, with a stack trace for an invocation point when one can be identified. Covered API areas include collections, reflection, file listing, and locale- or time-related methods. The listed requirements are Java 8–21, Maven 3.6+ with Surefire for the Maven plugin, or Gradle 5.0+ for the Gradle plugin. Linux and macOS are listed platforms; an automatic Gradle setup script is documented for both. Java 9 and later need module options in command-line setup instead of the Java 8 boot class path option. The license provides the software as-is without warranty.