Microsoft Code Coverage

What Microsoft Code Coverage is

Microsoft Code Coverage measures how much of a project’s code is exercised by coded tests, including unit tests. Its documented workflows cover .NET test projects using `dotnet test` and other .NET applications using the `dotnet-coverage` tool. It supports managed CLR and unmanaged native code, with static and dynamic instrumentation. When installed with MSTest, NUnit, or xUnit runners through Microsoft.Testing.Platform.MSBuild, coverage extensions are auto-registered. The MTP extension can produce coverage, XML, and Cobertura reports, and settings can control output, inclusion and exclusion rules, and instrumentation. The tooling supports Windows, macOS, and multiple Linux distributions, although instrumentation varies by operating system, version, and architecture. Other systems are supported on a best-effort basis, and some combinations allow static instrumentation only. Dynamic instrumentation on macOS and Linux requires libxml2; a missing dependency may leave an empty report. MTP excludes test assemblies by default unless configured otherwise. The free offering is closed-source, and the repository describes its content as documentation and samples for that functionality.

Who it suits

Microsoft Code Coverage suits developers measuring coverage in .NET test projects or other .NET applications. It is relevant to teams using supported test runners and operating systems.

Limits

The free plan costs nothing. Native coverage is disabled by default in the MTP extension, and MTP excludes test assemblies unless configured otherwise. Dynamic instrumentation on macOS and Linux requires libxml2; support also varies by OS, version and architecture.

Getting started

1. Open the Microsoft Code Coverage repository.
2. For .NET tests, collect coverage with `dotnet test`.
3. For another .NET application, use the `dotnet-coverage` tool.
4. For Microsoft.Testing.Platform, install the coverage extension with an MSTest, NUnit or xUnit runner.
5. Configure output, inclusion and exclusion rules, and instrumentation through runsettings or a coverage settings file.
6. On macOS or Linux, ensure libxml2 is available for dynamic instrumentation.

Verdict

Microsoft Code Coverage provides configurable coverage collection for .NET workflows across Windows, macOS, and Linux. Check the operating-system requirements and default test-assembly exclusion when setting up collection.