Hi Manuel,

> Is Parsec's ParserError missing an Eq instance
> What is the recommended way to use HUnit to test Parsec parsers?

In my project, I implemented Eq for ParseError locally.


{-# OPTIONS_GHC -fno-warn-orphans #-}

import Text.ParserCombinators.Parsec.Error(ParseError, Message, errorMessages, messageEq)

instance Eq ParseError where
   a == b = errorMessages a == errorMessages b

instance Eq Message where
   (==) = messageEq


I don't know if it was intentionally left out or not.  You might get more responses on Haskell-Cafe.

-Greg