Add work item existence validation feature

[Copilot]

Overview

This PR adds the ability to validate that work items referenced in commits and pull requests actually exist in Azure DevOps, not just that they match the AB#123 format. This addresses the feature request to catch typos and invalid work item references before code is merged.

Problem

Previously, the action only validated that commit messages and PR descriptions contained the AB# format but didn't verify whether the referenced work items actually existed in Azure DevOps. This could lead to:

• Commits with typos in work item numbers being merged
• Code linked to non-existent work items
• Reduced traceability between code changes and work items

Solution

Added a new optional input parameter verify-work-items-exist that enables validation of work item existence via the Azure DevOps API. When enabled, the action:

1. Extracts work item IDs from commits and PR body/title using the existing regex pattern
2. Calls the Azure DevOps API to verify each work item exists
3. Fails the action with a clear error message if any work item doesn't exist
4. Handles edge cases gracefully (connection failures, missing credentials, etc.)

Example

Before (format validation only):

Commit: "AB#99999 - Fix bug"
✅ PASS (AB# format found, but work item may not exist)

After (with verify-work-items-exist: true):

Commit: "AB#99999 - Fix bug"  
❌ FAIL: Work item 99999 does not exist in Azure DevOps

Usage

- name: Azure DevOps Commit Validator and Pull Request Linker
  uses: joshjohanning/azdo_commit_message_validator@v2
  with:
    verify-work-items-exist: true  # Enable work item validation
    azure-devops-organization: my-org
    azure-devops-token: ${{ secrets.AZURE_DEVOPS_PAT }}

Key Changes

• New module: validateWorkItem.js - Validates work item existence using azure-devops-node-api
• Updated action.yml: Added validation calls for both commit messages and PR body/title
• New input: verify-work-items-exist (defaults to false for backward compatibility)
• Enhanced documentation: Updated README.md with feature details and examples
• Comprehensive tests: Added 5 new tests covering success cases, errors, and edge cases

Backward Compatibility

This feature is fully backward compatible:

• Defaults to false - existing workflows are unaffected
• Only requires Azure DevOps credentials when enabled
• Shows a warning (not error) if enabled without credentials
• All existing functionality remains unchanged

Benefits

1. Early error detection - Catch invalid work item references before merge
2. Improved traceability - Ensure all code changes link to valid work items
3. Better compliance - Automatically enforce work item policies
4. Clear feedback - Descriptive error messages guide users to fix issues
5. Optional - Teams can opt-in when ready

Testing

All 33 tests passing ✅

• 25 bash tests (existing)
• 8 JavaScript tests (3 existing + 5 new)

New test coverage includes:

• Work item exists validation
• Non-existent work item handling
• Connection failure handling
• Null response handling
• Module export validation

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• dev.azure.com
  • Triggering command: node /home/REDACTED/work/azdo_commit_message_validator/azdo_commit_message_validator/node_modules/.bin/jest (dns block)
  • Triggering command: node /home/REDACTED/work/azdo_commit_message_validator/azdo_commit_message_validator/node_modules/.bin/jest --testNamePattern=should export (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

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This section details on the original issue you should resolve

<issue_title>Validate that work item exists</issue_title>
<issue_description>In addition to seeing if there is a valid link, ie AB#xyz, validate that it is a valid work item. This will require a valid Azure DevOps PAT though, whereas today you can get by without providing a token if you just want to simply verify the AB# exists.

Maybe add a new input for "verify-work-items-exist" </issue_description>

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

Fixes #64

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