Basic haskell support

ftplugin/haskell/sideways.vim

@@ -0,0 +1,32 @@
+if exists('b:sideways_definitions')
+  finish
+endif
+
+" \   {
+" \     'start':       '\%(^\s*\|[=(]\s*\)\k\{1,} \ze\s*[^=,*/%<>+-]',
+" \     'end':         '\s*\%(=\|--\)',
+" \     'delimiter':   ' \+',
+" \     'brackets':    ['([{"', ')]}"'],
+" \   },
+
+let b:sideways_definitions = [
+      \   {
+      \     'start':     '\k\+\s*::\s*',
+      \     'end':       '\s*\%(--\|$\)',
+      \     'delimiter': '\s*->\s*',
+      \     'brackets':  ['([{"', ')]}"'],
+      \   },
+      \   {
+      \     'start':     '\',
+      \     'end':       '->',
+      \     'delimiter': ' \+',
+      \     'brackets':  ['', ''],
+      \   },
+      \   {
+      \     'start':       '^\s*\k\{1,} \ze\s*[^=,*/%<>+-]',
+      \     'end':         '\s*\%(=\|--\)',
+      \     'brackets':    ['([{"', ')]}"'],
+      \     'single_line': 1,
+      \     'delimited_by_whitespace': 1,
+      \   },
+      \ ]

spec/plugin/haskell_spec.rb

@@ -0,0 +1,64 @@
+require 'spec_helper'
+
+describe "haskell" do
+  let(:filename) { 'test.hs' }
+
+  specify "function type definition" do
+    set_file_contents <<-EOF
+      function :: X -> Y -> Integer
+      function x y = 13
+    EOF
+
+    vim.search('X')
+    vim.right
+    assert_file_contents <<-EOF
+      function :: Y -> X -> Integer
+      function x y = 13
+    EOF
+
+    vim.left
+    assert_file_contents <<-EOF
+      function :: X -> Y -> Integer
+      function x y = 13
+    EOF
+  end
+
+  specify "lambda function arguments" do
+    set_file_contents <<-EOF
+      let l = \\x y z -> 13
+    EOF
+
+    vim.search('x')
+    vim.right
+    assert_file_contents <<-EOF
+      let l = \\y x z -> 13
+    EOF
+
+    vim.right
+    assert_file_contents <<-EOF
+      let l = \\y z x -> 13
+    EOF
+
+    vim.right
+    assert_file_contents <<-EOF
+      let l = \\x z y -> 13
+    EOF
+  end
+
+  specify "function definitions" do
+    set_file_contents <<-EOF
+      add x y = x + y
+    EOF
+
+    vim.search('add \zsx')
+    vim.right
+    assert_file_contents <<-EOF
+      add y x = x + y
+    EOF
+
+    vim.right
+    assert_file_contents <<-EOF
+      add x y = x + y
+    EOF
+  end
+end