testing package.json and impliedNodeFormat

[craigphicks]

@sheetalkamat -

Re your pull #48889

I created a test to check the value of impliedNodeFormat from inside a transformer when

• tsconfig:module is set to "Node12", and
• package.json exists and type is "commonjs"

I expected that impliedNodeFormat would be ModuleKind.CommonJS. However it is currently undefined,
so the test will not pass.

I know there a good chance that I am misunderstanding how it should work.
If you can help me I would greatly appreciate it.

I created a new test borrowing from src/testRunner/unittests/tsbuildWatch/publicApi.ts
It is src/testRunner/unittests/tsbuildWatch/publicApiImpliedNodeFormat.ts

I has additional file shared/package.json:

{
                name:"shared",
                version:"1.0.0",
                type:"commonjs",
}

that is added to the list passed to createWatchedSystem.

I also added internal getModuleResolutionCache() to SolutionBuilder just to see what was in it, and it is just an empty object {}. Is that correct?

[typescript-bot]

This PR doesn't have any linked issues. Please open an issue that references this PR. From there we can discuss and prioritise.

[craigphicks]

Compiler options not set correctly. Closing.