fix: don't error out while catching a `buildStart` error

[agilgur5]

Summary

If an error occurs during the buildStart hook, make sure that the buildEnd hook doesn't hide the error with its own error

• in this case the buildDone func had an uninitialized cache var, as it's initialized in buildStart after this thrown error
• Fixes #421
  • See root cause analysis in https://github.com/ezolenko/rollup-plugin-typescript2/issues/421#issuecomment-1247116271
  • Caused by #414 + #415

Details

• per in-line comment, if an error occurs during buildStart initialization, then the cache may not exist yet during buildDone

  • since we now use context.error instead of throw during initialization (from the options -> buildStart change), buildEnd will run during initialization - and the cache var is initialized in buildStart as well, so if an error occurs before then, the cache won't exist - we should gracefully handle this in all cases, since it's possible that even creating the cache could throw an error

• this error was hiding the underlying error, which was problematic for DX as well as bug reports (see my issue follow-up)

• add an integration test for tsconfig to make sure this code works

  • while this is similar to the previous tsconfig integration tests (that were moved to unit tests), this covers all cases of buildStart errors, and is not specific to the different tsconfig errors (unlike the unit tests)
  • this test will fail without the source code changes in this commit

Misc Notes

Would be good for a patch release! Especially as this error currently hides actual errors 😕

[Eonasdan]

Hi this is currently causing issues in one of my projects. Could you push this out please?

[agilgur5]

@Eonasdan this has been released in 0.34.1