Azure DevOps provides branch policies as a feature to enforce certain rules and quality checks on code branches within your Git repositories. These policies help maintain code quality, prevent errors, and ensure that code meets specific criteria before it can be merged into protected branches. Here are the key aspects of Azure DevOps branch policies:

1. Branch Protection:

   • Branch policies are often applied to protected branches, such as the “main” or “master” branch. These branches are typically considered stable and should meet certain quality standards.

2. Code Review:

   • One of the most common branch policies is the requirement for code reviews. Pull requests (PRs) must be reviewed and approved by one or more team members before they can be merged.

3. Build Validation:

   • You can configure branch policies to trigger automated builds (CI builds) when changes are pushed to a branch. The build must succeed before the code can be merged.

4. Status Checks:

   • Status checks allow you to define custom checks that must pass before a PR can be completed. These checks can include code analysis, testing, and other validation processes.

5. Required Reviewers:

   • You can enforce that a specific number of reviewers (or specific individuals) must approve a PR before it can be merged. This ensures that changes are reviewed by the appropriate experts.

6. Work Item Association:

   • You can require that PRs are linked to work items (e.g., user stories, tasks, bugs) in Azure DevOps Boards. This helps maintain traceability between code changes and work items.

7. Comment Requirements:

   • Branch policies can enforce that PRs must have specific comments or work item associations to provide context or justification for the changes.

8. Policy Notifications:

   • Azure DevOps can send notifications to team members when branch policies are violated or when PRs are awaiting approval.

9. Enforcement Level:

   • Branch policies can be set to “Blocking” or “Required” levels. Blocking policies prevent code from being merged until the policy is satisfied, while required policies inform but don’t block merges.

10. Automated Testing:

    • You can integrate automated testing tools into branch policies to ensure that code changes don’t introduce regressions or break existing functionality.

11. Continuous Integration (CI) Pipelines:

    • Branch policies often include integration with CI pipelines. Code changes are built and tested automatically, and the results are reported in the PR.

12. Branch Policy Scope:

    • Policies can be applied at the repository level or specific branch level. You can have different policies for different branches within the same repository.

13. Custom Policies:

    • Azure DevOps allows you to define custom branch policies using Azure Pipelines YAML files. This flexibility enables you to create policies tailored to your project’s needs.

Branch policies in Azure DevOps help teams maintain code quality, prevent accidental merges of untested code, and enforce coding standards. They promote collaboration and ensure that code changes are thoroughly reviewed and validated before becoming part of the main codebase.