Generating parser code from bnf creates multiple @NotNull annotations

[slideclimb]

As of Grammar-Kit 2020.3, the generate parser code action on a bnf file creates two @NotNull annotations in a lot of Impl class constructors. This results in an exception:

error: NotNull is not a repeatable annotation type 
public LatexParameterImpl(@NotNull @NotNull ASTNode node) {

Unfortunately, I have not been able to reproduce this behaviour anywhere else than the project where I encountered it, TeXiFy-IDEA. For example, it does not happen when running this action on the bnf in the Simple language plugin example.

When generating the parser code on Latex.bnf it generates, among others, the following constructor (for LatexParameterImpl):

public LatexParameterImpl(@NotNull @NotNull ASTNode node) {
    super(node);
}

For TeXiFy, it does this in all Latex...Impl classes except LatexCommandsImpl, where the constructors are

public LatexCommandsImpl(@NotNull LatexCommandsStub stub, @NotNull IStubElementType type) {
    super(stub, type);
}

public LatexCommandsImpl(@NotNull ASTNode node) {
    super(node);
}

public LatexCommandsImpl(LatexCommandsStub stub, IElementType type, ASTNode node) {
    super(stub, type, node);
}

as expected. This class is the only class that has a Mixin, which is the only difference I could find between this and the other classes/elements. I have no idea if this has something to do with it.

This behaviour did not exist in Grammar-Kit 2020.1, so I will downgrade to that version for now.

[gregsh]

Thanks, fixed. Feel free to grab the latest dev build.
As a workaround - use your own base element class instead of ASTWrapperPsiElement.