Get-PesterCodeCoverage

A GitHub Action that aggregates Pester code coverage reports and generates a detailed summary with coverage statistics. Fails the workflow if coverage falls below specified targets.

This GitHub Action is a part of the PSModule framework. It is recommended to use the Process-PSModule workflow to automate the whole process of managing the PowerShell module.

Features

• Combines multiple code coverage reports from parallel test runs
• Generates markdown/HTML tables showing missed & executed commands
• Displays analyzed files and coverage statistics
• Configurable step summary sections
• Threshold enforcement for minimum code coverage

Usage

Inputs

Name	Description	Required	Default
Debug	Enable debug output	No	false
Verbose	Enable verbose output	No	false
Version	Exact version of GitHub module to install	No	Latest
Prerelease	Allow prerelease versions	No	false
WorkingDirectory	Working directory for the action	No	.
StepSummary_Mode	Controls which sections to show in the GitHub step summary. Use 'Full' for all sections, 'None' to disable, or a comma-separated list of 'Missed, Executed, Files'.	No	Missed, Files
CodeCoveragePercentTarget	Target code coverage percentage	No	Max target from individual reports

Example Workflow

    - name: Process Code Coverage
      uses: PSModule/Get-PesterCodeCoverage@v1
      with:
        StepSummary_Mode: Full
        CodeCoveragePercentTarget: 80

Outputs

GitHub Step Summary

The action generates a detailed summary visible in the GitHub Actions UI:

1. Coverage Overview Table

   • Coverage percentage vs target
   • Analyzed/executed/missed command counts
   • Number of files analyzed

2. Expandable Sections

   • Missed Commands: HTML table with code snippets
   • Executed Commands: HTML table with code snippets
   • Analyzed Files: List of covered files

Example summary:

✅ Code Coverage Report

Summary:
| Coverage | Target | Analyzed      | Executed      | Missed        | Files         |
|----------|--------|---------------|---------------|---------------|---------------|
| 85%      | 80%    | 1000 commands | 850 commands  | 150 commands  | 15 files      |

▶️ Missed commands [150] (click to expand)
▶️ Executed commands [850] (click to expand)
▶️ Files analyzed [15] (click to expand)

Requirements

1. Pester Code Coverage Reports Preceding steps must generate JSON coverage reports named *-CodeCoverage*.json

2. GitHub CLI The action uses gh run download to fetch artifacts from the current workflow run

Behavior

1. Coverage Calculation

   • Combines multiple coverage reports
   • Removes duplicate entries
   • Calculates aggregate coverage percentage

2. Threshold Enforcement Fails the workflow if coverage is below either:

   • Explicitly specified CodeCoveragePercentTarget
   • Highest target from individual reports (if no target specified)

3. Output Control Configure visibility of sections using StepSummary_Mode:

   # Show all sections
   StepSummary_Mode: Full
   
   # Disable summary
   StepSummary_Mode: None
   
   # Custom selection
   StepSummary_Mode: Missed, Files

Troubleshooting

Enable debugging by setting inputs:

with:
  Debug: true
  Verbose: true