Feature: Support shallow cloning of git repositories

[joaopbnogueira]

Description

This PR adds support for shallow cloning of git repositories. While having the full git history available is the only way to truly be certain of the next version, this is not desirable on larger repositories with many thousands of commits as a full clone can take several minutes and is usually neither desirable nor needed as there is sufficient information (e.g. git tags) available on the N most recent commits to be able to reliably determine the next version without requiring a full clone.

Since this is a special scenario it put behind an explicit flag allowshallow to ensure both backwards compatibility and awareness of the user of the tool.

Motivation and Context

Observation that the git checkout step on CI pipelines is taking 5-20 minutes on large internal repositories due to having to fetch the whole history as required by GitVersion. This step sometimes represents more time than the rest of the steps, leading to costs and undesirable long iteration cycles.

How Has This Been Tested?

• Unit tests

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[Copilot]

Pull Request Overview

This PR adds support for shallow cloning of git repositories through an explicit flag, allowing users to bypass the full-history clone for improved performance on large repositories. Key changes include the addition of the AllowShallow flag in settings and command-line arguments, updates to GitPreparer to conditionally allow shallow clones, and comprehensive tests and documentation updates supporting the new feature.

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/GitVersion.MsBuild/msbuild/tools/GitVersion.MsBuild.props	Added MSBuild properties and tool arguments for shallow cloning support
src/GitVersion.Core/PublicAPI.Shipped.txt	Updated public API to expose the new AllowShallow flag
src/GitVersion.Core/Options/Settings.cs	Introduced the AllowShallow setting
src/GitVersion.Core/Core/GitPreparer.cs	Modified shallow repository handling to log a warning when AllowShallow is enabled
src/GitVersion.Core.Tests/Core/GitVersionExecutorTests.cs	Added unit tests to validate the shallow clone behavior with AllowShallow flag
src/GitVersion.App/Arguments.cs	Included the AllowShallow flag in application arguments
src/GitVersion.App/ArgumentParserExtensions.cs	Extended boolean arguments to include allowshallow
src/GitVersion.App/ArgumentParser.cs	Integrated allowshallow parsing logic
src/GitVersion.App.Tests/ArgumentParserTests.cs	Added tests to verify correct parsing of the allowshallow argument
docs/input/docs/usage/msbuild.md, docs/input/docs/usage/cli/arguments.md, docs/input/docs/reference/requirements.md	Updated documentation to reflect shallow cloning support

Comments suppressed due to low confidence (1)

src/GitVersion.App.Tests/ArgumentParserTests.cs:633

• [nitpick] The test method name 'AllowshallowTrueWhenDefined' is inconsistent with the PascalCase used elsewhere for the 'AllowShallow' property. Consider renaming it to 'AllowShallowTrueWhenDefined' for consistency.

public void AllowshallowTrueWhenDefined()

[arturcic]

@joaopbnogueira good stuff, mind to rebase on top of main and add the new argument to https://github.com/GitTools/GitVersion/blob/main/src/GitVersion.App.Tests/HelpWriterTests.cs#L18
I will then take these changes for a spin, want to test some scenarios

[joaopbnogueira]

Thanks @arturcic will do, I'll be off for 2 weeks but will pick this up as soon as I'm back.

Edit: found a few minutes and just did it, ready to take it for a spin @arturcic .