Shell-like syntax for interactive mode

src/GHCMod/Options.hs

@@ -27,6 +27,7 @@ import Control.Arrow
 import GHCMod.Options.Commands
 import GHCMod.Version
 import GHCMod.Options.DocUtils
+import GHCMod.Options.ShellEscape
 
 parseArgs :: IO (Options, GhcModCommands)
 parseArgs =
@@ -36,9 +37,9 @@ parseArgs =
            $$  fullDesc
            <=> header "ghc-mod: Happy Haskell Programming"
 
-parseArgsInteractive :: [String] -> Maybe (GhcModCommands, [String])
+parseArgsInteractive :: String -> Maybe (GhcModCommands, [String])
 parseArgsInteractive args =
-  getParseResult $ execParserPure (prefs idm) opts args
+  getParseResult $ execParserPure (prefs idm) opts $ parseCmdLine args
   where
     opts = info interactiveCommandsSpec $$ fullDesc
 

src/GHCMod/Options/Commands.hs

@@ -13,8 +13,6 @@
 --
 -- You should have received a copy of the GNU Affero General Public License
 -- along with this program.  If not, see <http://www.gnu.org/licenses/>.
-{-# LANGUAGE TupleSections #-}
-
 module GHCMod.Options.Commands where
 
 import Options.Applicative

src/GHCMod/Options/ShellEscape.hs

@@ -0,0 +1,55 @@
+-- ghc-mod: Making Haskell development *more* fun
+-- Copyright (C) 2015  Nikolay Yakimov <root@livid.pp.ru>
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero General Public License as published by
+-- the Free Software Foundation, either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU Affero General Public License for more details.
+--
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <http://www.gnu.org/licenses/>.
+module GHCMod.Options.ShellEscape (parseCmdLine) where
+
+import Data.Char
+import Data.Maybe
+
+isQuote :: Char -> Bool
+isQuote = (`elem` "\"'")
+
+isEscapeChar :: Char -> Bool
+isEscapeChar = (==) '\\'
+
+isEscapable :: Char -> Bool
+isEscapable c = any ($ c) [isSpace, isQuote, isEscapeChar]
+
+go :: String -> String -> [String] -> Maybe Char -> [String]
+-- result
+go [] curarg accargs _ = reverse $ reverse curarg : accargs
+-- escaped character
+go (esc:c:cl) curarg accargs quote
+  | isEscapeChar esc
+  = if isEscapable c
+    then go cl (c:curarg) accargs quote
+    else go (c:cl) ('\\':curarg) accargs quote
+-- quote character -- opens quotes
+go (c:cl) curarg accargs Nothing
+  | isQuote c = go cl curarg accargs (Just c)
+-- close quotes
+go (c:cl) curarg accargs (Just q)
+  | c == q = go cl curarg accargs Nothing
+go (c:cl) curarg accargs quotes
+  -- space separates argumetns outside quotes
+  | isSpace c && isNothing quotes
+  = if null curarg
+      then go cl curarg accargs quotes
+      else go cl [] (reverse curarg : accargs) quotes
+  -- general character
+  | otherwise = go cl (c:curarg) accargs quotes
+
+parseCmdLine :: String -> [String]
+parseCmdLine comline = go comline [] [] Nothing