Coverlet is a cross platform code coverage library for .NET Core, with support for line and method coverage.

Available on NuGet

Visual Studio:

PM> Install-Package coverlet.msbuild

.NET Core CLI:

dotnet add package coverlet.msbuild

Coverlet integrates with the MSBuild system and that allows it to go through the following process:

• Locate the unit test assembly and selects all the referenced assemblies that have PDBs.
• Instruments the selected assemblies by inserting code to record sequence point hits to a temporary file.

• Restore the original non-instrumented assembly files.
• Read the recorded hits information from the temporary file.
• Generate the coverage result from the hits information and write it to a file.

Coverlet doesn't require any additional setup other than including the NuGet package. It integrates with the dotnet test infrastructure built into the .NET Core CLI and when enabled will automatically generate coverage results after tests are run.

Enabling code coverage is as simple as setting the CollectCoverage property to true

dotnet test /p:CollectCoverage=true

After the above command is run, a coverage.json file containing the results will be generated in the root directory of the test project. A summary of the results will also be displayed in the terminal.

Coverlet can generate coverage results in multiple formats, which is specified using the CoverletOutputFormat property. Possible values include json (default), lcov and opencover. For example, the following command emits coverage results in the opencover format:

dotnet test /p:CollectCoverage=true /p:CoverletOutputFormat=opencover

The output folder of the coverage result file can also be specified using the CoverletOutputDirectory property.

• Branch coverage
• Console runner (removes the need for requiring a NuGet package)

If you find a bug or have a feature request, please report them at this repository's issues section. Contributions are highly welcome, however, except for very small changes, kindly file an issue and let's have a discussion before you open a pull request.

This project is licensed under the MIT license. See the LICENSE file for more info.