Testing

Testing source generators is tricky. You can't run the generators directly from code because it's the IDE that loads the generators, not your tests.

So the tests are in two solutions:

• In the main solution, there are snapshot tests which create in-memory projects that exercise the generators using different versions of the .NET Framework. These are slow to run because they use many different permutations of features and dozens of variations of configuration/primitive-type/C#-type/accessibility-type/converters, for example:

  • does it correctly generate a record struct with instances and normalization and a type converter and a Dapper serializer?

  • does it correctly generate a class with no converters, no validation, and no serialization?

  • does it correctly generate a readonly struct with a LinqToDb converter?

  • etc. etc.

  (all tests run for each supported framework)

The snapshot tests in the IDE run in about 5 minutes. In the CI build, we set a THOROUGH flag which exercises more variations, and that can take up to several hours.

• In the consumer solution, the tests involve consuming the 'real' Vogen NuGet package and exercising it via real C# code. To ensure it tests the latest version of Vogen, test.ps1 first builds Vogen, then forces a NuGet package to be built locally with a version of 999.9.xxx. These tests are much quicker to run. They verify the behavior of created Value Objects, such as:

  • Normalization

  • Equality

  • Hashing

  • ToString

  • Validation

  • Instance Fields