test-coverage-gate

Test Coverage Gate

Overview

Untested code is unverified code. Shipping without coverage data is shipping blind.

This skill enforces minimum test coverage thresholds before code leaves your machine. It detects your coverage tool, runs the analysis, compares results against thresholds, and blocks shipping if coverage is insufficient.

Core principle: No code ships without meeting coverage thresholds. Period.

Iron Law:

NO SHIP WITHOUT COVERAGE GATE PASSING
If coverage is below threshold, the PR does not get created.

When to Use

Always, before:

• Running /ship to create a PR
• Merging feature branches
• Tagging releases
• Deploying to staging or production

Especially when:

• Adding new features (new code must be tested)
• Refactoring (coverage must not drop)
• Fixing bugs (regression test required)
• Touching critical paths (auth, payments, data processing)

Skip only when:

• Documentation-only changes (no source code modified)
• Configuration file changes (non-code)
• Generated code explicitly excluded from coverage

Configuration

Default Thresholds

Line Coverage:     80%
Branch Coverage:   80%
Function Coverage: 80%

Custom Thresholds

Override defaults per project via codingbuddy.config.json, package.json, or tool-native config:

// codingbuddy.config.json
{
  "coverage": {
    "thresholds": {
      "lines": 80,
      "branches": 80,
      "functions": 80
    },
    "tool": "auto",        // "vitest" | "jest" | "c8" | "istanbul" | "auto"
    "excludePatterns": [
      "**/*.config.*",
      "**/generated/**",
      "**/migrations/**"
    ]
  }
}

// package.json (alternative)
{
  "coverageGate": {
    "lines": 80,
    "branches": 80,
    "functions": 80
  }
}

Per-Tool Native Config

If thresholds are already defined in your test tool's config, the gate respects them:

Tool	Config Location
Vitest	vitest.config.ts → test.coverage.thresholds
Jest	jest.config.ts → coverageThreshold.global
c8	.c8rc.json or package.json → c8
Istanbul/nyc	.nycrc or package.json → nyc