Please consider adding PyPy Trove classifiers, because apparently black works fine! At least on the recent PyPy (I tested PyPy3.6 v7.0 on macOS). I used version 18.9b0 of black. See https://pypy.org/download.html

#4478 included some initial support for the new ConstBlock expression kind variant, but there's opportunities to enhance and improve the formatting.

The relevant section of the codebase can be found in formatting/expr.rs
https://github.com/rust-lang/rustfmt/blob/cbe01e47024c852e2ed852671e76f7929c4bab91/src/formatting/expr.rs#L127-L129

There are 3 core activities to completing this issue:

When I try to beautify the i get the following problem
TypeError: Cannot read property 'on' of undefined

I just installed beautify and uncrustify

https://gist.github.com/ODCA117/917affd6b11437517535a45350379820

I really don't know if we have some rules to create Mercosul/Brazilian license plate, but I think that we should keep support for both (after 2024 we can drop Brazilian support since Brazil will only use Mercosul format).