For the following code:

public interface Interface1 {}
public interface Interface 2 {}
public T myMethod(T input) {}

a code generator (javax.annotation.processing.Processor) in eclipse will have a TypeVariable for the return type T instead of a DeclaredType.

This results in a stack overflow exception, because the return value of Collections.singletonList(upperBound) ends up returning a list containing, in essence, the input parameter.

Fixes TypesTest#getTypeVariableTypeMirror

Did a copy-paste from TypeKind.DECLARED and missed that there's no need to re-create a list here.

If TypeParameterElement#getBounds does the trick, why complicate it?  This works both in eclipse as well as javac.