NumericUnderscores is not supported

[sir4ur0n]

Problem

Hindent doesn't seem to support NumericUnderscores.

• I checked the issue tracker for existing issues about this problem.
• I'm using the latest version of hindent. (5.2.7)

Input haskell

{-# LANGUAGE NumericUnderscores #-}

module Foo where

foo = 10_000

Expected output haskell

{-# LANGUAGE NumericUnderscores #-}

module Foo where

foo = 10_000

Actual output haskell

{-# LANGUAGE NumericUnderscores #-}

module Foo where

foo = 10 _000

Note the space between 10 and _000.

Also doesn't work when the extension is enabled in Stack package.yaml.

[merc1031]

I ran into a similar issue in Floskell and opened Numeric Litaral Issues in HSE, but it was blocking me so I submitted HexFloatLiterals in HSE and building on it NumericUndersores in HSE.

Hoping they get merged in at some point