ln-513-regression-checker

Runs existing test suite to catch regressions after implementation changes. Use when Story needs regression verification. No status changes.

310 stars

Best use case

ln-513-regression-checker is best used when you need a repeatable AI agent workflow instead of a one-off prompt.

Runs existing test suite to catch regressions after implementation changes. Use when Story needs regression verification. No status changes.

Teams using ln-513-regression-checker should expect a more consistent output, faster repeated execution, less prompt rewriting.

When to use this skill

  • You want a reusable workflow that can be run more than once with consistent structure.

When not to use this skill

  • You only need a quick one-off answer and do not need a reusable workflow.
  • You cannot install or maintain the underlying files, dependencies, or repository context.

Installation

Claude Code / Cursor / Codex

$curl -o ~/.claude/skills/ln-513-regression-checker/SKILL.md --create-dirs "https://raw.githubusercontent.com/levnikolaevich/claude-code-skills/main/skills-catalog/ln-513-regression-checker/SKILL.md"

Manual Installation

  1. Download SKILL.md from GitHub
  2. Place it in .claude/skills/ln-513-regression-checker/SKILL.md inside your project
  3. Restart your AI agent — it will auto-discover the skill

How ln-513-regression-checker Compares

Feature / Agentln-513-regression-checkerStandard Approach
Platform SupportNot specifiedLimited / Varies
Context Awareness High Baseline
Installation ComplexityUnknownN/A

Frequently Asked Questions

What does this skill do?

Runs existing test suite to catch regressions after implementation changes. Use when Story needs regression verification. No status changes.

Where can I find the source code?

You can find the source code on GitHub using the link provided at the top of the page.

SKILL.md Source

> **Paths:** File paths (`shared/`, `references/`, `../ln-*`) are relative to skills repo root. If not found at CWD, locate this SKILL.md directory and go up one level for repo root. If `shared/` is missing, fetch files via WebFetch from `https://raw.githubusercontent.com/levnikolaevich/claude-code-skills/master/skills/{path}`.

# Regression Checker

**Type:** L3 Worker
**Category:** 5XX Quality

Runs the existing test suite to ensure no regressions after implementation changes.

## Inputs

| Input | Required | Source | Description |
|-------|----------|--------|-------------|
| `storyId` | Yes | args, git branch, kanban, user | Story to process |

**Resolution:** Story Resolution Chain.
**Status filter:** To Review

## Purpose & Scope
- Detect test framework (pytest/jest/vitest/go test/etc.) and test dirs.
- Execute full suite; capture stdout/stderr for Story quality gate.
- Return PASS/FAIL with counts/log excerpts; never modifies Linear or kanban.
- Preserve full stdout/stderr output for downstream log analysis.

## When to Use
- After code quality checks pass
- Code quality check passed

## Workflow

### Phase 0: Resolve Inputs

**MANDATORY READ:** Load `shared/references/input_resolution_pattern.md`, `shared/references/ci_tool_detection.md`

1. **Resolve storyId:** Run Story Resolution Chain per guide (status filter: [To Review]).

### Phase 1: Execute Tests

**MANDATORY READ:** Load `shared/references/output_normalization.md`

Read target project files if they exist: `docs/project/infrastructure.md`, `docs/project/runbook.md`

1) Auto-discover test framework per ci_tool_detection.md Command Registry (Test Frameworks section).
2) Get service endpoints, port allocation from infrastructure.md. Get exact test commands, Docker setup, environment variables from runbook.md. Runbook commands take priority over auto-detection (per ci_tool_detection.md Discovery Hierarchy).
3) Build appropriate test command; run with timeout (5min per ci_tool_detection.md); capture stdout/stderr.
4) Parse results: passed/failed counts; key failing tests.
5) **Normalize + group failures:** Apply `shared/references/output_normalization.md` §1-§3 to test output. Group failing tests by error category (Import/Module, Assertion, Timeout, Type, Connection, Runtime). Report grouped: e.g., "3 Import errors in auth/, 2 Assertion mismatches in payment/".
6) Output verdict JSON (PASS or FAIL + grouped failures list) and add Linear comment.

## Critical Rules
- No selective test runs; run full suite.
- Do not fix tests or change status; only report.
- Language preservation in comment (EN/RU).

## Runtime Summary Artifact

**MANDATORY READ:** Load `shared/references/quality_summary_contract.md`

Accept optional `summaryArtifactPath`.

Summary kind:
- `quality-worker`

Required payload semantics:
- `worker = "ln-513"`
- `status`
- `verdict`
- `issues`
- `warnings`
- `artifact_path`

Write the summary to the provided artifact path or return the same envelope in structured output.

## Definition of Done

- [ ] Framework detected; command executed
- [ ] Results parsed; verdict produced with failing tests (if any)
- [ ] Linear comment posted with summary

## Reference Files
- Risk-based limits used downstream: `shared/references/risk_based_testing_guide.md`
- **CI tool detection:** `shared/references/ci_tool_detection.md`
- **Output normalization:** `shared/references/output_normalization.md`
- **Pytest patterns:** `references/pytest_configuration.md`

---
**Version:** 3.1.0
**Last Updated:** 2026-01-09

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