[Monotone-devel] Support meld merge tool

[Wojciech Miłkowski]

Hello,

I have just rewritten merge2() and merge3() lua hooks to support 
interesting (and easy to use) merge tool called meld 
(http://meld.sourceforge.net/).
If someone find it useful I attach '.monotonerc' that supports it.
There's one disadvantage because of limitation in program command line. 
You can put 3 names of files to perform 3-way merge, but you cannot 
qualify output one, so I decided arbitrary to choose left file in 2-way 
merge and center (ancestry) file to in case of 3-way merge.
There's warning generated on console to notice that.

Have a fun
Wojtek


----------------------------------------------------------------------
Najlepsze auto, najlepsze moto... >>> http://link.interia.pl/f1841

-- merger support

function merge2_meld_cmd(lfile, rfile)
   local cmd_fmt = "meld %s %s"
   return string.format(cmd_fmt, lfile, rfile)
end

function merge3_meld_cmd(lfile, afile, rfile)
   local cmd_fmt = "meld %s %s %s" 
   return string.format(cmd_fmt, lfile, afile, rfile)
end

function merge2(left_path, right_path, merged_path, left, right)
   local lfile = nil
   local rfile = nil
   local outfile = nil
   local data = nil
   
   local meld_exists = false

   lfile = write_to_temporary_file(left)
   rfile = write_to_temporary_file(right)
   outfile = write_to_temporary_file("")

   if lfile ~= nil and
      rfile ~= nil and
      outfile ~= nil 
   then 
      local cmd = nil
      if program_exists_in_path("meld") then
         meld_exists = true
         io.write(string.format("\nWARNING: 'meld' was choosen to perform 
external 2-way merge.\nYou should merge all changes to *LEFT* file due to 
limitation of program\narguments.\n\n"))
         cmd = merge2_meld_cmd(lfile, rfile) 
      elseif program_exists_in_path("xxdiff") then
         cmd = merge2_xxdiff_cmd(left_path, right_path, merged_path, 
                                 lfile, rfile, outfile)
      elseif program_exists_in_path("emacs") then
         cmd = merge2_emacs_cmd("emacs", lfile, rfile, outfile)
      elseif program_exists_in_path("xemacs") then
         cmd = merge2_emacs_cmd("xemacs", lfile, rfile, outfile)
      end

      if cmd ~= nil
      then
         io.write(string.format("executing external 2-way merge command: %s\n", 
cmd))
         os.execute(cmd)
         if meld_exists then
            data = read_contents_of_file(lfile)
         else
            data = read_contents_of_file(outfile)
         end
         if string.len(data) == 0 
         then 
            data = nil
         end
      else
         io.write("no external 2-way merge command found\n")
      end
   end
   
   os.remove(lfile)
   os.remove(rfile)
   os.remove(outfile)

   return data
end

function merge3(anc_path, left_path, right_path, merged_path, ancestor, left, 
right)
   local afile = nil
   local lfile = nil
   local rfile = nil
   local outfile = nil
   local data = nil
   
   local meld_exists = false

   lfile = write_to_temporary_file(left)
   afile = write_to_temporary_file(ancestor)
   rfile = write_to_temporary_file(right)
   outfile = write_to_temporary_file("")

   if lfile ~= nil and
      rfile ~= nil and
      afile ~= nil and
      outfile ~= nil 
   then 
      local cmd = nil
      
      if program_exists_in_path("meld") then
         meld_exists = true
         io.write(string.format("\nWARNING: 'meld' was choosen to perform 
external 3-way merge.\nYou should merge all changes to *CENTER* file due to 
limitation of program\narguments.\n\n"))
         cmd = merge3_meld_cmd(lfile, afile, rfile)
      elseif program_exists_in_path("xxdiff") then
         cmd = merge3_xxdiff_cmd(left_path, anc_path, right_path, merged_path, 
                                 lfile, afile, rfile, outfile)
      elseif program_exists_in_path("emacs") then
         cmd = merge3_emacs_cmd("emacs", lfile, afile, rfile, outfile)
      elseif program_exists_in_path("xemacs") then
         cmd = merge3_emacs_cmd("xemacs", lfile, afile, rfile, outfile)
      end

      if cmd ~= nil
      then
         io.write(string.format("executing external 3-way merge command: %s\n", 
cmd))
         os.execute(cmd)
         if meld_exists then
            data = read_contents_of_file(afile)
         else
            data = read_contents_of_file(outfile)
         end
         if string.len(data) == 0 
         then 
            data = nil
         end
      else
         io.write("no external 3-way merge command found\n")
      end
   end
   
   os.remove(lfile)
   os.remove(rfile)
   os.remove(afile)
   os.remove(outfile)
   
   return data
end