buck2-test-workflow

You can automate post-change Buck2 testing by running a comprehensive workflow that validates modified targets, executes recursive package tests, and performs target determination to ensure code quality. This prevents downstream breakage after changing BUILD and PACKAGE files.

The best way to run recursive package tests is using the ... pattern to catch issues across subpackages. This approach validates immediate targets and executes comprehensive package-wide tests to ensure downstream compatibility after modifications.

Target determination in Buck2 analyzes your changes to identify all affected targets and their reverse dependencies. This mechanism ensures you build and test only the necessary downstream targets, verifying compatibility without running the entire project test suite.

Yes, you can check reverse dependencies to prevent downstream breakage. The workflow includes optional reverse-dependency verification alongside immediate target tests and recursive package testing to ensure your changes do not break downstream consumers.

Yes, the workflow supports both immediate target validation and recursive testing. It orchestrates immediate target tests to ensure modified targets pass locally, while also applying the ... pattern to catch issues across subpackages for comprehensive coverage.

Relying only on immediate target tests misses issues in subpackages and downstream consumers. Without recursive package testing and reverse-dependency checks, changes to BUILD or PACKAGE files can cause undetected downstream breakage across your Buck2 project.