normalize-imports

Install

$ stack install

Sort and align Haskell import statements

Given a file

import Foo
import qualified Bar

import FooBar
import Baz

when you run :%!normalize-imports in Vim, you will get

import qualified Bar
import           Foo

import           Baz
import           FooBar

(better still, map it in your .vimrc, e.g. map <Leader>f :%!normalize-import <CR>