Rfmt mangles partial application of operators

[feihong]

Js.log("45" |> (++)(_, "%"));

Turns into

Js.log("45" |> _ ++ "%");

Which doesn't compile.

Melange playground link

Note that if it's not an operator, it's fine. For example, this won't get mangled:

Js.log("45" |> String.cat(_, "%"));