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.

Regression Checker

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

Inputs

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 docs/project/infrastructure.md, docs/project/runbook.md, shared/references/output_normalization.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).

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