git-difftool--helper.sh

   1 #!/bin/sh
   2 # git-difftool--helper is a GIT_EXTERNAL_DIFF-compatible diff tool launcher.
   3 # This script is typically launched by using the 'git difftool'
   4 # convenience command.
   5 #
   6 # Copyright (c) 2009, 2010 David Aguilar
   7
   8 TOOL_MODE=diff
   9 . git-mergetool--lib
  10
  11 # difftool.prompt controls the default prompt/no-prompt behavior
  12 # and is overridden with $GIT_DIFFTOOL*_PROMPT.
  13 should_prompt () {
  14         prompt_merge=$(git config --bool mergetool.prompt || echo true)
  15         prompt=$(git config --bool difftool.prompt || echo $prompt_merge)
  16         if test "$prompt" = true
  17         then
  18                 test -z "$GIT_DIFFTOOL_NO_PROMPT"
  19         else
  20                 test -n "$GIT_DIFFTOOL_PROMPT"
  21         fi
  22 }
  23
  24 # Indicates that --extcmd=... was specified
  25 use_ext_cmd () {
  26         test -n "$GIT_DIFFTOOL_EXTCMD"
  27 }
  28
  29 launch_merge_tool () {
  30         # Merged is the filename as it appears in the work tree
  31         # Local is the contents of a/filename
  32         # Remote is the contents of b/filename
  33         # Custom merge tool commands might use $BASE so we provide it
  34         MERGED="$1"
  35         LOCAL="$2"
  36         REMOTE="$3"
  37         BASE="$1"
  38
  39         # $LOCAL and $REMOTE are temporary files so prompt
  40         # the user with the real $MERGED name before launching $merge_tool.
  41         if should_prompt
  42         then
  43                 printf "\nViewing: '$MERGED'\n"
  44                 if use_ext_cmd
  45                 then
  46                         printf "Hit return to launch '%s': " \
  47                                 "$GIT_DIFFTOOL_EXTCMD"
  48                 else
  49                         printf "Hit return to launch '%s': " "$merge_tool"
  50                 fi
  51                 read ans
  52         fi
  53
  54         if use_ext_cmd
  55         then
  56                 export BASE
  57                 eval $GIT_DIFFTOOL_EXTCMD '"$LOCAL"' '"$REMOTE"'
  58         else
  59                 run_merge_tool "$merge_tool"
  60         fi
  61 }
  62
  63 if ! use_ext_cmd
  64 then
  65         if test -n "$GIT_DIFF_TOOL"
  66         then
  67                 merge_tool="$GIT_DIFF_TOOL"
  68         else
  69                 merge_tool="$(get_merge_tool)" || exit
  70         fi
  71 fi
  72
  73 # Launch the merge tool on each path provided by 'git diff'
  74 while test $# -gt 6
  75 do
  76         launch_merge_tool "$1" "$2" "$5"
  77         shift 7
  78 done