--- a/plugin/lawrencium.vim	Fri Dec 18 13:17:54 2015 +0100
+++ b/plugin/lawrencium.vim	Fri Feb 19 15:50:34 2016 -0800
@@ -61,11 +61,6 @@
     return fnamemodify(a:path, ':s?[/\\]$??')
 endfunction
 
-" Surrounds the given string with double quotes.
-function! s:addquotes(str)
-    return '"' . a:str . '"'
-endfunction
-
 " Returns whether a path is absolute.
 function! s:isabspath(path)
     return a:path =~# '\v^(\w\:)?[/\\]'
@@ -356,24 +351,38 @@
     if a:0 == 1 && type(a:1) == type([])
         let l:arg_list = a:1
     endif
+    let l:prev_shellslash = &shellslash
+    setlocal noshellslash
     let l:hg_command = g:lawrencium_hg_executable . ' --repository ' . shellescape(s:stripslash(self.root_dir))
     let l:hg_command = l:hg_command . ' ' . a:command
     for l:arg in l:arg_list
-        if stridx(l:arg, ' ') >= 0
-            let l:hg_command = l:hg_command . ' "' . l:arg . '"'
-        else
-            let l:hg_command = l:hg_command . ' ' . l:arg
-        endif
+		let l:hg_command = l:hg_command . ' ' . shellescape(l:arg)
     endfor
+    if l:prev_shellslash
+        setlocal shellslash
+    endif
     return l:hg_command
 endfunction
 
 " Runs a Mercurial command in the repo.
 function! s:HgRepo.RunCommand(command, ...) abort
+    let l:all_args = [1, a:command] + a:000
+    return call(self['RunCommandEx'], l:all_args, self)
+endfunction
+
+function! s:HgRepo.RunCommandEx(plain_mode, command, ...) abort
+    let l:prev_hgplain = $HGPLAIN
+    if a:plain_mode
+        let $HGPLAIN = 'true'
+    endif
     let l:all_args = [a:command] + a:000
     let l:hg_command = call(self['GetCommand'], l:all_args, self)
     call s:trace("Running Mercurial command: " . l:hg_command)
-    return system(l:hg_command)
+    let l:cmd_out = system(l:hg_command)
+    if a:plain_mode
+        let $HGPLAIN = l:prev_hgplain
+    endif
+    return l:cmd_out
 endfunction
 
 " Runs a Mercurial command in the repo and reads its output into the current
@@ -672,7 +681,7 @@
     if l:rev == ''
         call a:repo.ReadCommandOutput('cat', a:full_path)
     else
-        call a:repo.ReadCommandOutput('cat', '-r', s:addquotes(l:rev), a:full_path)
+        call a:repo.ReadCommandOutput('cat', '-r', l:rev, a:full_path)
     endif
 endfunction
 
@@ -723,11 +732,11 @@
         let l:rev1 = strpart(a:path_parts['value'], 0, l:commaidx)
         let l:rev2 = strpart(a:path_parts['value'], l:commaidx + 1)
         if l:rev1 == '-'
-            let l:diffargs = [ '-r', s:addquotes(l:rev2) ]
+            let l:diffargs = [ '-r', l:rev2 ]
         elseif l:rev2 == '-'
-            let l:diffargs = [ '-r', s:addquotes(l:rev1) ]
+            let l:diffargs = [ '-r', l:rev1 ]
         else
-            let l:diffargs = [ '-r', s:addquotes(l:rev1), '-r', s:addquotes(l:rev2) ]
+            let l:diffargs = [ '-r', l:rev1, '-r', l:rev2 ]
         endif
     elseif a:path_parts['value'] != ''
         let l:diffargs = [ '-c', a:path_parts['value'] ]
@@ -887,7 +896,7 @@
         " to make auto-completed paths work magically.
         execute 'cd! ' . fnameescape(l:repo.root_dir)
     endif
-    let l:output = call(l:repo.RunCommand, a:000, l:repo)
+    let l:output = call(l:repo.RunCommandEx, [0] + a:000, l:repo)
     if g:lawrencium_auto_cd
         execute 'cd! -'
     endif