subtest-isolation

Create minimal reproduction subtests to isolate and debug failing tests.

29|4|Updated Dec 2, 2025
One-click install
npx skills add https://github.com/bearcove/pikru --skill subtest-isolation
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: subtest-isolation
Source: https://github.com/bearcove/pikru/tree/main/.claude/skills/subtest-isolation
Command: npx skills add https://github.com/bearcove/pikru --skill subtest-isolation

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Complex test failures often hide under layers of interaction, making it hard to identify the exact cause. This skill provides a disciplined approach to isolate issues by crafting minimal subtests that reproduce a single problem.

Core Features & Use Cases

  • Create small, focused test fragments that reproduce the failure with only the necessary elements.
  • Incrementally add targeted debug output and inspect state to reveal root causes.
  • Validate fixes in both the isolated subtest and the original test to prevent regressions.

Quick Start

Create a minimal reproduction subtest file that reproduces the failure and run it against the test suite to verify the issue.

Frequently Asked Questions about subtest-isolation

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I isolate a failing test to find the root cause of a bug?

To isolate a failing test, you create a minimal reproduction subtest that triggers the exact bug with only the necessary elements. This disciplined subtest workflow verifies the failure and helps identify the root cause.

What is the best way to debug complex test failures hidden by interaction layers?

The best way to debug complex test failures is using a subtest isolation workflow. This approach involves crafting a minimal subtest, incrementally adding targeted debug output, and inspecting state to reveal the root cause.

How do I create a minimal reproduction for a failing test?

You create a minimal reproduction by writing a small, focused test fragment that reproduces the failure with only the necessary elements. Run this isolated subtest against your test suite to verify the issue.

How do I verify a fix for an isolated bug without causing regressions?

To verify a fix without regressions, validate the solution in both the isolated subtest and the original test. Comparing against baseline implementations confirms the issue is resolved before deciding to keep or remove the subtest.

When should I use subtest isolation for debugging?

You should use subtest isolation when complex test failures hide under layers of interaction, making it hard to identify the exact cause. Creating a minimal subtest isolates a single problem for focused diagnostics.

Can I compare baseline implementations to confirm a test failure issue?

Yes, you can compare against baseline implementations to confirm the issue. This subtest isolation workflow includes applying targeted diagnostics and verifying failure to precisely identify the root cause.