xUnit Parallel Example

This is a playground environment to see what impacts tests running in parallel.

• https://xunit.net/docs/running-tests-in-parallel
• https://xunit.net/docs/configuration-files

Running

Requires

• .NET Core 3.0

In Visual Studio 2019, open Test Explorer and click Run All Tests

• Note: In the Test Explorer there is a setting of Run Tests In Parallel. Play around with this & xunit.runner.json

Design

From xUnit's documentation, this is the expected behaviour:

• Tests in same TestCollection (by default, a class) will run sequentially
• Tests in different TestCollections will run in parallel
• Assemblies will not run in parallel but can be changed via configuration

Configuration

Unit Tests

• Run tests in parallel in same assembly
• Run tests in parallel with other assemblies

Component Tests

• Does not run tests in parallel in same assembly
• Run tests in parallel with other assemblies

Integration Tests

• Does not run tests in parallel in same assembly
• Does not run tests in parallel with other assemblies

Issues

Visual Studio 2019 parallel settings appears to completely ignore xunit.runner.json

• Disabling running in parallel, no assembly runs in parallel
• Enabling running in parallel, all assemblies run in parallel

Contributing & Feedback

Feel free to make an issue / PR for any mistakes I've made