Add coverage CI workflow

[Copilot]

• Add SKIP_AI_ENFORCEMENT: 1 environment variable to coverage steps
• Applied to both coverage-text and coverage-html steps
• Matches pattern from testing.yml workflow
• Skips AI enforcement tests that require third-party tools (cargo machete, Ansible, OpenTofu)
• YAML linting passes

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Create coverage CI workflow</issue_title>
<issue_description>Parent Epic: #85

Overview

Create a GitHub Actions workflow to generate code coverage reports on every push and pull request. The workflow generates coverage in two formats: a text summary for immediate viewing in the workflow output, and an HTML report uploaded as an artifact for detailed inspection.

Note: This issue does NOT include Codecov or other external coverage service integration.

Goals

• Generate coverage reports automatically in CI/CD for all branches
• Display coverage summary in workflow output (text format)
• Make detailed HTML coverage reports available as artifacts
• Add .coverage/ directory to .gitignore

Specifications

Workflow Structure

Trigger Events: Push and pull_request (following testing.yml pattern)

Job: Single coverage job with these steps:

1. Checkout code - actions/checkout@v4
2. Setup Rust toolchain - dtolnay/rust-toolchain@stable
3. Enable caching - Swatinem/rust-cache@v2
4. Install cargo-llvm-cov - taiki-e/install-action@v2
5. Generate text coverage - cargo cov
6. Generate HTML report - cargo cov-html
7. Upload HTML artifact - actions/upload-artifact@v4

Example Workflow

name: Coverage

on:
  push:
  pull_request:

env:
  CARGO_TERM_COLOR: always

jobs:
  coverage:
    name: Coverage Report
    runs-on: ubuntu-latest

    steps:
      - id: checkout
        name: Checkout Repository
        uses: actions/checkout@v4

      - id: setup
        name: Setup Toolchain
        uses: dtolnay/rust-toolchain@stable

      - id: cache
        name: Enable Workflow Cache
        uses: Swatinem/rust-cache@v2

      - id: install-llvm-cov
        name: Install cargo-llvm-cov
        uses: taiki-e/install-action@v2
        with:
          tool: cargo-llvm-cov

      - id: coverage-text
        name: Generate Text Coverage Summary
        run: cargo cov

      - id: coverage-html
        name: Generate HTML Coverage Report
        run: cargo cov-html

      - id: upload-coverage
        name: Upload HTML Coverage Report
        uses: actions/upload-artifact@v4
        with:
          name: coverage-html-report
          path: target/llvm-cov/html/
          retention-days: 30

Implementation Plan

Phase 1: Update .gitignore (5 minutes)

• Add .coverage/ directory to .gitignore with comment

Phase 2: Create Workflow (15 minutes)

• Create .github/workflows/coverage.yml
• Add trigger events and environment variables
• Set up job structure

Phase 3: Configure Toolchain (10 minutes)

• Add Rust toolchain setup, caching, and cargo-llvm-cov installation

Phase 4: Generate Reports (15 minutes)

• Add text and HTML coverage generation steps

Phase 5: Upload Artifact (10 minutes)

• Add artifact upload step with 30-day retention

Phase 6: Testing (15 minutes)

• Test workflow on a feature branch
• Verify text output and HTML artifact availability

Acceptance Criteria

• .coverage/ directory added to .gitignore
• Workflow file exists at .github/workflows/coverage.yml
• Workflow triggers on push and pull_request
• Text coverage summary visible in workflow output
• HTML coverage artifact uploaded with 30-day retention
• Workflow does NOT block CI/CD on coverage failures

Notes

• Uses cov and cov-html aliases from .cargo/config.toml
• Follows patterns from existing testing.yml workflow
• Non-blocking by design - coverage is informational only
• Future enhancement: External coverage service integration can be added later</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Create coverage CI workflow #87

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[josecelano]

@copilot in the steps:

- id: coverage-text
  name: Generate Text Coverage Summary
  run: cargo cov

- id: coverage-html
  name: Generate HTML Coverage Report
  run: cargo cov-html

We need to skip the AI ENFORCEMENT tests. Some tests run E2E tests that require some third-party tools to be installed like: cargo machete, Ansible, OpenTofu. We do not need to run those tests to generate the code coverage. We nned to add the env var SKIP_AI_ENFORCEMENT with value 1 like the testing workflow (.github/workflows/testing.yml)

- id: test
  name: Run Unit Tests
  env:
    SKIP_AI_ENFORCEMENT: 1
  run: cargo test --tests --benches --examples --workspace --all-targets --all-features

[Copilot]

@copilot in the steps:

...

Added SKIP_AI_ENFORCEMENT: 1 to both coverage steps. This skips AI enforcement tests that require third-party tools. (commit b4092b6)

[josecelano]

ACK b4092b6