snapshot-testing

Automate regression detection by comparing current test outputs against approved baselines. This approach captures actual API responses and serializes them into files, enabling quick visual diffs and streamlined version control-based reviews.

Snapshot testing captures actual outputs and compares them against approved baselines to detect regressions. It uses scrubbers to neutralize dynamic values like dates or IDs, stabilizing the baselines across different runs and environments.

Set up a baseline workflow by running a test on your rendered content to generate a received file. You then review and approve this file to establish the verified baseline, which future test runs will automatically compare against.

Snapshot testing works effectively with serialized data in .NET projects. By configuring the Verify framework in your test project, you can capture and compare serialized outputs to guard against unintended changes in your data structures.

Snapshot tests fail across environments when baselines contain dynamic values that change per run. You need to apply scrubbers to neutralize these volatile elements, ensuring the baseline files remain stable regardless of where the tests execute.

The best way to review changes is using a received versus verified file workflow. This method captures the new HTTP response output in a received file, allowing you to compare it directly against the approved baseline before committing updates.