bug: Exceptions thrown from dataFetchers are being thrown as `java.lang.reflect.UndeclaredThrowableException`.

[maory]

Expected behavior

DataFetcherExceptionHandler#onExceptionhandlerParameters Will contain the thrown exception.

Actual behavior

DataFetcherExceptionHandler#onExceptionhandlerParameters contains java.lang.reflect.UndeclaredThrowableException, it's cause is the right exception.

Steps to reproduce

1. Create a simple query.
2. Create a test class for it
3. mocked class will throw a custom Exception (inherited from Exception)
4. set a breakPoint DataFetcherExceptionHandler#onException, see that the exception is java.lang.reflect.UndeclaredThrowableException

Note: DataFetcher does throw the right exception and declares about it.

[berngp]

Hi @maory, we will need a minimal test to reproduce the issue. We use this feature extensibly.

If you need an example, and a way to set some breakpoint, you can look at our MicrometerServletSmokeTest.

[maory]

Hey @berngp, found out this issue https://github.com/graphql-java-kickstart/graphql-java-tools/issues/477 in graphql-java which might be relevant.

The test case can be the same.