src/Darcs/Patch/Show.lhs

   1 %  Copyright (C) 2002-2005 David Roundy
   2 %
   3 %  This program is free software; you can redistribute it and/or modify
   4 %  it under the terms of the GNU General Public License as published by
   5 %  the Free Software Foundation; either version 2, or (at your option)
   6 %  any later version.
   7 %
   8 %  This program is distributed in the hope that it will be useful,
   9 %  but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 %  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 %  GNU General Public License for more details.
  12 %
  13 %  You should have received a copy of the GNU General Public License
  14 %  along with this program; see the file COPYING.  If not, write to
  15 %  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16 %  Boston, MA 02110-1301, USA.
  17
  18
  19 \begin{code}
  20 {-# OPTIONS_GHC -cpp -fno-warn-orphans #-}
  21 {-# LANGUAGE CPP #-}
  22
  23 module Darcs.Patch.Show ( showPatch_, showNamedPrefix )
  24              where
  25
  26 import Prelude hiding ( pi )
  27
  28 import Printer ( Doc, renderString, vcat,
  29                  text, blueText,
  30                  ($$), (<+>) )
  31 import Darcs.Patch.Core ( Patch(..) )
  32 import Darcs.Patch.Prim ( showPrim, FileNameFormat(..) )
  33 import Darcs.Patch.Info ( PatchInfo, showPatchInfo )
  34 import Darcs.Ordered ( FL(NilFL), mapFL )
  35 #include "gadts.h"
  36 \end{code}
  37
  38 \section{Patch string formatting}
  39
  40 Of course, in order to store our patches in a file, we'll have to save them
  41 as some sort of strings.  The convention is that each patch string will end
  42 with a newline, but on parsing we skip any amount of whitespace between
  43 patches.
  44 \begin{code}
  45 instance Show (Patch C(x y))  where
  46     show p = renderString (showPatch_ p) ++ "\n"
  47
  48 showPatch_ :: Patch C(a b) -> Doc
  49 showPatch_ (PP p) = showPrim OldFormat p
  50 showPatch_ (ComP NilFL) = blueText "{" $$ blueText "}"
  51 showPatch_ (ComP ps)  = blueText "{"
  52                         $$ vcat (mapFL showPatch_ ps)
  53                         $$ blueText "}"
  54 showPatch_ (Merger _ _ p1 p2) = showMerger "merger" p1 p2
  55 showPatch_ (Regrem _ _ p1 p2) = showMerger "regrem" p1 p2
  56 \end{code}
  57
  58 \paragraph{Merger patches}
  59 Merge two patches.  The MERGERVERSION is included to allow some degree of
  60 backwards compatibility if the merger algorithm needs to be changed.
  61 \begin{verbatim}
  62 merger MERGERVERSION
  63 <first patch>
  64 <second patch>
  65 \end{verbatim}
  66 \begin{code}
  67 showMerger :: String -> Patch C(a b) -> Patch C(d e) -> Doc
  68 showMerger merger_name p1 p2 =
  69     blueText merger_name <+> text "0.0" <+> blueText "("
  70                            $$ showPatch_ p1
  71                            $$ showPatch_ p2
  72                            $$ blueText ")"
  73 \end{code}
  74
  75 \paragraph{Named patches}
  76
  77 Named patches are displayed as a ``patch id'' which is in square brackets,
  78 followed by a patch.  Optionally, after the patch id (but before the patch
  79 itself) can come a list of dependencies surrounded by angle brackets.  Each
  80 dependency consists of a patch id.
  81
  82 \begin{code}
  83 showNamedPrefix :: PatchInfo -> [PatchInfo] -> Doc
  84 showNamedPrefix n d = showPatchInfo n
  85                    $$ blueText "<"
  86                    $$ vcat (map showPatchInfo d)
  87                    $$ blueText ">"
  88
  89 \end{code}