---
titel: "Bug fix with a regression-test cycle"
adresse: https://anvil-coder.tech/en/use-cases/bugfix-regressionstest-zyklus
beschreibung: "A reported bug first gets a regression test that demonstrably shows it red, then the fix, until that same test turns green."
sprache: en
---

Use cases

# Bug fix with a regression-test cycle

A reported bug first gets a regression test that demonstrably shows it red, then the fix, until that same test turns green.

## Case study in full

Synthetic example — illustrative magnitudes, not a measurement.

Stack profile: `php-laravel-13` · Data origin: Synthetic example, not a reference run. · Measurement period: —

A reproducible bug has been reported, but no test captures it permanently. Without such a test, the same bug can return unnoticed as soon as the affected code changes again.

**Out of scope — not automated:** Not automated: classifying the bug as reproducible and relevant remains a human decision, as does approving the fix and its counter-check before the merge.

### Prerequisites

- A reproducible bug report described in the tracker.

- A stack profile with the project's existing test commands.

- Guardrails that record a test obligation for bug fixes.

- Approval that the fix including a regression test may be carried out.

### Workflow

- The bug report from the tracker is turned into a plan with a reproduction step.

- A regression test is added that demonstrably shows the bug as red before the fix.

- The actual fix is implemented until that same test turns green.

- The counter-check runs against the full affected test suite, not just the new test.

- The result goes out as a pull request to the repository, referencing the bug report.

### Result artifacts

- The new regression test stays part of the test suite and guards against recurrence.

- Before/after status of the test traceable in the commit history.

- One pull request referencing the original bug report.

- A note on whether related code paths were checked for the same bug.

### Key figures

Scope

**Stories/tickets**

1

**Slices**

3

**Files/modules**

6

Throughput

**Validated slices**

3

**Retries**

3

**Human approvals**

1

Quality

**Checks run**

Reproduktionstest, Regressionstest, Vollständige Testsuite

**Gates passed**

3

**Gates failed**

1

**Remaining debt**

A related code path was flagged as possibly affected and logged as a separate ticket for review.

Resources — no pricing

**Prompt tokens**

40000

**Completion tokens**

15000

**Cache tokens**

50000

**Model calls**

20

**Sandbox runtime**

5 minutes

**Model/stack context**

Stack: PHP with Laravel 13, MVC (profile php-laravel-13).

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Every example on this page was created for illustration. It is not a promise about the duration, quality or cost of a future run of your own — your own figures appear in the cockpit after logging in, within your own tenant context.

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