pulumi/pkg/codegen/testing/test/README.md

SDK Codegen Tests

TestSDKCodegen runs the complete set of SDK code generation tests against a particular language's code generator. It also verifies that the generated code is structurally sound.

The test files live in pkg/codegen/testing/test/testdata and are registered in the following globals in pkg/codegen/testing/test.

• sdk_driver.go: PulumiPulumiSDKTests
• program_driver.go: PulumiPulumiProgramTests
• program_driver.go: PulumiPulumiYAMLProgramTests

An SDK code generation test files consists of a schema and a set of expected outputs for each language. Each test is structured as a directory that contains that information:

 testdata/
     my-simple-schema/   # i.e. `simple-enum-schema`
         schema.(json|yaml)
         go/
         python/
         nodejs/
         dotnet/
         ...

The schema is the only piece that must be manually authored.

Once the schema has been written, the actual codegen outputs can be generated by running the following in pkg/codegen directory:

PULUMI_ACCEPT=true go test ./...

This will rebuild subfolders such as go/ from scratch and store the set of code-generated file names in go/codegen-manifest.json. To generate the code for a specific directory in testdata, run the following instead:

PULUMI_ACCEPT=true go test ./... -run TestGenerate/$dirName

If these outputs look correct, they need to be checked into git and will then serve as the expected values for the normal test runs:

$ go test ./...

That is, the normal test runs will fail if changes to codegen or schema lead to a diff in the generated file set. If the diff is intentional, it can be accepted again via PULUMI_ACCEPT=true.

Writing Program Tests on Generated Code

To support running unit tests over the generated code, the tests also support mixing in manually written $lang-extras files into the generated tree. For example, given the following input:

 testdata/
     my-simple-schema/
         schema.json
         go/
         go-extras/
             tests/
                 go_test.go

The system will copy go-extras/tests/go_test.go into go/tests/go_test.go before performing compilation and unit test checks over the project generated in go.