From 562a5610357ea4c9d8dfb58f1b4257b72f61ce1d Mon Sep 17 00:00:00 2001
From: Greg Hurrell <greg@hurrell.net>
Date: Sat, 4 Jun 2016 23:12:13 -0700
Subject: [PATCH] Suppress unwanted trailing whitespace

---
 docvim.cabal                                      |  2 ++
 lib/Docvim/Printer/Vim.hs                         | 15 +++++++++++----
 .../fixtures/vim/integration-ferret-plugin.golden |  2 +-
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/docvim.cabal b/docvim.cabal
index 9dc976d..bc69e16 100644
--- a/docvim.cabal
+++ b/docvim.cabal
@@ -82,6 +82,7 @@ library
                ,    optparse-applicative
                ,    parsec
                ,    pretty-show
+               ,    split
                ,    transformers
   default-language:    Haskell2010
   exposed-modules:  Docvim.AST
@@ -119,6 +120,7 @@ test-suite tasty
                ,    parsec
                ,    pretty-show
                ,    process
+               ,    split
                ,    tasty
                ,    tasty-golden
                ,    tasty-hunit
diff --git a/lib/Docvim/Printer/Vim.hs b/lib/Docvim/Printer/Vim.hs
index fda1d13..2f66df0 100644
--- a/lib/Docvim/Printer/Vim.hs
+++ b/lib/Docvim/Printer/Vim.hs
@@ -10,6 +10,7 @@ import Control.Monad.Reader
 import Control.Monad.State
 import Data.Char (isSpace, toUpper)
 import Data.List (intercalate, isSuffixOf, span, sort)
+import Data.List.Split (splitOn)
 import Data.Tuple (swap)
 import Docvim.AST
 import Docvim.Parse (parseUnit, rstrip)
@@ -37,7 +38,7 @@ textwidth :: Int
 textwidth = 78
 
 vimHelp :: Node -> String
-vimHelp n = rstrip output ++ "\n"
+vimHelp n = suppressTrailingWhitespace output ++ "\n"
   where metadata = Metadata (getSymbols n) (getPluginName n)
         context = Context defaultLineBreak ""
         operations = evalState (runReaderT (node n) metadata) context
@@ -47,16 +48,22 @@ vimHelp n = rstrip output ++ "\n"
         reduce acc (Slurp atom) = if isSuffixOf atom acc
                                   then take (length acc - length atom) acc
                                   else acc
+        suppressTrailingWhitespace str = rstrip $ intercalate "\n" (map rstrip (splitOn "\n" str))
 
 -- Helper function that appends and updates `partialLine` context.
 append :: String -> Env
 append string = do
   context <- get
   -- TODO obviously tidy this up
-  -- TODO: always suppress trailing whitespace (some of it is making it into the
-  -- output)
   let (ops, line) = if length (partialLine context) + length leading >= textwidth
-                    then ([Delete (length $ snd $ split $ partialLine context), Slurp " ", Append (lineBreak context), Append (snd $ split $ partialLine context), Append $ string], lineBreak context ++ (snd $ split $ partialLine context) ++ string)
+                    then ( [ Delete (length $ snd $ split $ partialLine context)
+                           , Slurp " "
+                           , Append (lineBreak context)
+                           , Append (snd $ split $ partialLine context)
+                           , Append $ string
+                           ]
+                          , lineBreak context ++ (snd $ split $ partialLine context) ++ string
+                          )
                     else ([Append string], partialLine context ++ string)
   put (Context (lineBreak context) (end line))
   return ops
diff --git a/tests/fixtures/vim/integration-ferret-plugin.golden b/tests/fixtures/vim/integration-ferret-plugin.golden
index cc5a20d..e2a258d 100644
--- a/tests/fixtures/vim/integration-ferret-plugin.golden
+++ b/tests/fixtures/vim/integration-ferret-plugin.golden
@@ -200,7 +200,7 @@ Note that including quotes will not do what you intend.
 >
      " Search for '"foo' in the 'bar"' directory:
      :Ack "foo bar"
-    
+
      " Search for "'foo' in the "bar'" directory:
      :Ack 'foo bar'
 <
-- 
2.40.1