PR Metrics

PR Metrics is a both a GitHub Action and Azure DevOps Pipelines task for adding size and test coverage indicators to the start of each Pull Request title.

The Azure Pipelines task can be downloaded from the Visual Studio Marketplace.

For example, a PR with the title "Adding code" could become either:

• XS ✔️ ▪️ Adding code
• L ⚠️ ▪️ Adding code

The former would indicate an extra small PR with sufficient test coverage, whereas the latter would indicate a large PR with insufficient test coverage.

This task helps ensure engineers keep PRs to an appropriate size with appropriate test coverage, while informing reviewers of the expected time commitment for a thorough review of the code.

The task will also add a comment to the PR with a detailed breakdown of the metrics:

Metrics for iteration 1

✔️ Thanks for keeping your pull request small.

✔️ Thanks for adding tests.

	Lines
Product Code	100
Test Code	50
Subtotal	150
Ignored	5
Total	155

It will furthermore add a comment to indicate that review of specific excluded files is unnecessary.

❗ This file doesn't require review.

If no PR description is provided, the description will be set to:

❌ Add a description.

Inputs

You will need to set the environment variable PR_Metrics_Access_Token to a Personal Access Token (PAT) with at least Read and Write access to pull requests. If you are using a Classic PAT, it will need at least the 'repos' scope. Instructions on creating a new PAT can be found here. Alternatively, you can use the in-built GITHUB_TOKEN.

If using GITHUB_TOKEN, the following permissions are required:

permissions:
  pull-requests: write
  statuses: write

GitHub token permissions can be set for an individual job, workflow, or for Actions as a whole.

It is also recommended that you set continue-on-error: true as a failure within the action should not break your pipelines and prevent code development.

base-size

The maximum number of new lines in an extra small PR. If left blank, a default of 200 will be used.

growth-rate

The growth rate applied to the base size for calculating the size of larger PRs. If left blank, a default of 2.0 will be used. With a base size of 200 and a growth rate of 2.0, 400 new lines would constitute a medium PR while 800 new lines would constitute a large PR.

test-factor

The lines of test code expected for each line of product code. If left blank, a default of 1.0 will be used. This can be set to 0.0 in order to skip the reporting of the test code coverage.

file-matching-patterns

Globs specifying the files and folders to include. Autogenerated files should typically be excluded. Excluded files will contain a comment to inform reviewers that they are unlikely to need to review those files. If left blank, a default of

**/*
!**/package-lock.json

(all files except package-lock.json) will be used.

code-file-extensions

Extensions for files containing code, so that non-code files can be excluded. If left blank, a default set of file extensions will be used, which are listed here.

Example Usage

The default input values are expected to be appropriate for most builds. Therefore, the following YAML definition is recommended:

uses: microsoft/PR-Metrics@v1.6.3
name: PR Metrics
env:
  PR_METRICS_ACCESS_TOKEN: ${{ secrets.GITHUB_TOKEN }}
continue-on-error: true

If you wish to modify the inputs, YAML akin the to the following can be used:

uses: microsoft/PR-Metrics@v1.6.3
name: PR Metrics
env:
  PR_METRICS_ACCESS_TOKEN: ${{ secrets.GITHUB_TOKEN }}
with:
  base-size: 200
  growth-rate: 2.0
  test-factor: 1.0
  file-matching-patterns: |
    **/*
    !Ignore.cs    
  code-file-extensions: |
    cs
    ps1    
continue-on-error: true

pull_request must be used as the pipeline trigger to ensure that sufficient information, including the Pull Request ID, is available to PR Metrics. pull_request_target will not work as insufficient information is available when using this trigger.

Instructions on using the action within Azure Pipelines can be found here.

Git History

If your repository contains any non-linear history, it will be necessary to fetch Git history during checkout. This can be done by updating the actions/checkout step:

- uses: actions/checkout@4.1.7
  fetch-depth: 0

In many cases, fetch-depth will not be required so it is recommended not to set this unless the action explicitly requests it. It may also be possible to set this to a value greater than 0 if you only require a partial history, but it can be difficult to determine a value that will work consistently, due to the nature of Git history.

To avoid this, it is recommended to only use commit types that squash the Git history such as "squash merge" or "rebase and fast-forward".

Troubleshooting

A set of steps for troubleshooting any issues encountered can be found here.

Contributing

Instructions on contributing can be located in CONTRIBUTING.md.

The code is released under the MIT license.

PR Metrics is created by the OMEX team in Microsoft, which is part of the Office organization. Additional source code released by the OMEX team can be located at https://github.com/microsoft/Omex.

Code of Conduct

This project has adopted the Microsoft Open Source Code of Conduct. For more information, see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.