Parenthesis highlight goes haywire if one or more Char parenthesis is present.

[aa8y]

Looks like the Char parenthesis (and square and curly braces) are not ignored while the String ones are.

[fldef]

It looks like vim is using style names to handle some matching logic. Changing syntax/scala.vim to use scalaCharacter (rather than scalaChar) fixes the problem for me. I'm guessing styles scala<whatever>String and scala<whatever>Comment work because they end with magic words.

[derekwyatt]

Care to put in a PR?