git-mergetool--lib.sh

   1 # git-mergetool--lib is a shell library for common merge tool functions
   2
   3 : ${MERGE_TOOLS_DIR=$(git --exec-path)/mergetools}
   4
   5 mode_ok () {
   6         if diff_mode
   7         then
   8                 can_diff
   9         elif merge_mode
  10         then
  11                 can_merge
  12         else
  13                 false
  14         fi
  15 }
  16
  17 is_available () {
  18         merge_tool_path=$(translate_merge_tool_path "$1") &&
  19         type "$merge_tool_path" >/dev/null 2>&1
  20 }
  21
  22 list_config_tools () {
  23         section=$1
  24         line_prefix=${2:-}
  25
  26         git config --get-regexp $section'\..*\.cmd' |
  27         while read -r key value
  28         do
  29                 toolname=${key#$section.}
  30                 toolname=${toolname%.cmd}
  31
  32                 printf "%s%s\n" "$line_prefix" "$toolname"
  33         done
  34 }
  35
  36 show_tool_names () {
  37         condition=${1:-true} per_line_prefix=${2:-} preamble=${3:-}
  38         not_found_msg=${4:-}
  39         extra_content=${5:-}
  40
  41         shown_any=
  42         ( cd "$MERGE_TOOLS_DIR" && ls ) | {
  43                 while read toolname
  44                 do
  45                         if setup_tool "$toolname" 2>/dev/null &&
  46                                 (eval "$condition" "$toolname")
  47                         then
  48                                 if test -n "$preamble"
  49                                 then
  50                                         printf "%s\n" "$preamble"
  51                                         preamble=
  52                                 fi
  53                                 shown_any=yes
  54                                 printf "%s%s\n" "$per_line_prefix" "$toolname"
  55                         fi
  56                 done
  57
  58                 if test -n "$extra_content"
  59                 then
  60                         if test -n "$preamble"
  61                         then
  62                                 # Note: no '\n' here since we don't want a
  63                                 # blank line if there is no initial content.
  64                                 printf "%s" "$preamble"
  65                                 preamble=
  66                         fi
  67                         shown_any=yes
  68                         printf "\n%s\n" "$extra_content"
  69                 fi
  70
  71                 if test -n "$preamble" && test -n "$not_found_msg"
  72                 then
  73                         printf "%s\n" "$not_found_msg"
  74                 fi
  75
  76                 test -n "$shown_any"
  77         }
  78 }
  79
  80 diff_mode() {
  81         test "$TOOL_MODE" = diff
  82 }
  83
  84 merge_mode() {
  85         test "$TOOL_MODE" = merge
  86 }
  87
  88 translate_merge_tool_path () {
  89         echo "$1"
  90 }
  91
  92 check_unchanged () {
  93         if test "$MERGED" -nt "$BACKUP"
  94         then
  95                 return 0
  96         else
  97                 while true
  98                 do
  99                         echo "$MERGED seems unchanged."
 100                         printf "Was the merge successful? [y/n] "
 101                         read answer || return 1
 102                         case "$answer" in
 103                         y*|Y*) return 0 ;;
 104                         n*|N*) return 1 ;;
 105                         esac
 106                 done
 107         fi
 108 }
 109
 110 valid_tool () {
 111         setup_tool "$1" && return 0
 112         cmd=$(get_merge_tool_cmd "$1")
 113         test -n "$cmd"
 114 }
 115
 116 setup_user_tool () {
 117         merge_tool_cmd=$(get_merge_tool_cmd "$tool")
 118         test -n "$merge_tool_cmd" || return 1
 119
 120         diff_cmd () {
 121                 ( eval $merge_tool_cmd )
 122         }
 123
 124         merge_cmd () {
 125                 trust_exit_code=$(git config --bool \
 126                         "mergetool.$1.trustExitCode" || echo false)
 127                 if test "$trust_exit_code" = "false"
 128                 then
 129                         touch "$BACKUP"
 130                         ( eval $merge_tool_cmd )
 131                         check_unchanged
 132                 else
 133                         ( eval $merge_tool_cmd )
 134                 fi
 135         }
 136 }
 137
 138 setup_tool () {
 139         tool="$1"
 140
 141         # Fallback definitions, to be overridden by tools.
 142         can_merge () {
 143                 return 0
 144         }
 145
 146         can_diff () {
 147                 return 0
 148         }
 149
 150         diff_cmd () {
 151                 return 1
 152         }
 153
 154         merge_cmd () {
 155                 return 1
 156         }
 157
 158         translate_merge_tool_path () {
 159                 echo "$1"
 160         }
 161
 162         if ! test -f "$MERGE_TOOLS_DIR/$tool"
 163         then
 164                 setup_user_tool
 165                 return $?
 166         fi
 167
 168         # Load the redefined functions
 169         . "$MERGE_TOOLS_DIR/$tool"
 170         # Now let the user override the default command for the tool.  If
 171         # they have not done so then this will return 1 which we ignore.
 172         setup_user_tool
 173
 174         if merge_mode && ! can_merge
 175         then
 176                 echo "error: '$tool' can not be used to resolve merges" >&2
 177                 return 1
 178         elif diff_mode && ! can_diff
 179         then
 180                 echo "error: '$tool' can only be used to resolve merges" >&2
 181                 return 1
 182         fi
 183         return 0
 184 }
 185
 186 get_merge_tool_cmd () {
 187         merge_tool="$1"
 188         if diff_mode
 189         then
 190                 git config "difftool.$merge_tool.cmd" ||
 191                 git config "mergetool.$merge_tool.cmd"
 192         else
 193                 git config "mergetool.$merge_tool.cmd"
 194         fi
 195 }
 196
 197 # Entry point for running tools
 198 run_merge_tool () {
 199         # If GIT_PREFIX is empty then we cannot use it in tools
 200         # that expect to be able to chdir() to its value.
 201         GIT_PREFIX=${GIT_PREFIX:-.}
 202         export GIT_PREFIX
 203
 204         merge_tool_path=$(get_merge_tool_path "$1") || exit
 205         base_present="$2"
 206
 207         # Bring tool-specific functions into scope
 208         setup_tool "$1" || return 1
 209
 210         if merge_mode
 211         then
 212                 run_merge_cmd "$1"
 213         else
 214                 run_diff_cmd "$1"
 215         fi
 216 }
 217
 218 # Run a either a configured or built-in diff tool
 219 run_diff_cmd () {
 220         diff_cmd "$1"
 221 }
 222
 223 # Run a either a configured or built-in merge tool
 224 run_merge_cmd () {
 225         merge_cmd "$1"
 226 }
 227
 228 list_merge_tool_candidates () {
 229         if merge_mode
 230         then
 231                 tools="tortoisemerge"
 232         else
 233                 tools="kompare"
 234         fi
 235         if test -n "$DISPLAY"
 236         then
 237                 if test -n "$GNOME_DESKTOP_SESSION_ID"
 238                 then
 239                         tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 240                 else
 241                         tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 242                 fi
 243                 tools="$tools gvimdiff diffuse diffmerge ecmerge"
 244                 tools="$tools p4merge araxis bc codecompare"
 245         fi
 246         case "${VISUAL:-$EDITOR}" in
 247         *vim*)
 248                 tools="$tools vimdiff emerge"
 249                 ;;
 250         *)
 251                 tools="$tools emerge vimdiff"
 252                 ;;
 253         esac
 254 }
 255
 256 show_tool_help () {
 257         tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"
 258
 259         tab='   '
 260         LF='
 261 '
 262         any_shown=no
 263
 264         cmd_name=${TOOL_MODE}tool
 265         config_tools=$({
 266                 diff_mode && list_config_tools difftool "$tab$tab"
 267                 list_config_tools mergetool "$tab$tab"
 268         } | sort)
 269         extra_content=
 270         if test -n "$config_tools"
 271         then
 272                 extra_content="${tab}user-defined:${LF}$config_tools"
 273         fi
 274
 275         show_tool_names 'mode_ok && is_available' "$tab$tab" \
 276                 "$tool_opt may be set to one of the following:" \
 277                 "No suitable tool for 'git $cmd_name --tool=<tool>' found." \
 278                 "$extra_content" &&
 279                 any_shown=yes
 280
 281         show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
 282                 "${LF}The following tools are valid, but not currently available:" &&
 283                 any_shown=yes
 284
 285         if test "$any_shown" = yes
 286         then
 287                 echo
 288                 echo "Some of the tools listed above only work in a windowed"
 289                 echo "environment. If run in a terminal-only session, they will fail."
 290         fi
 291         exit 0
 292 }
 293
 294 guess_merge_tool () {
 295         list_merge_tool_candidates
 296         cat >&2 <<-EOF
 297
 298         This message is displayed because '$TOOL_MODE.tool' is not configured.
 299         See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
 300         'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
 301         $tools
 302         EOF
 303
 304         # Loop over each candidate and stop when a valid merge tool is found.
 305         for tool in $tools
 306         do
 307                 is_available "$tool" && echo "$tool" && return 0
 308         done
 309
 310         echo >&2 "No known ${TOOL_MODE} tool is available."
 311         return 1
 312 }
 313
 314 get_configured_merge_tool () {
 315         # Diff mode first tries diff.tool and falls back to merge.tool.
 316         # Merge mode only checks merge.tool
 317         if diff_mode
 318         then
 319                 merge_tool=$(git config diff.tool || git config merge.tool)
 320         else
 321                 merge_tool=$(git config merge.tool)
 322         fi
 323         if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 324         then
 325                 echo >&2 "git config option $TOOL_MODE.tool set to unknown tool: $merge_tool"
 326                 echo >&2 "Resetting to default..."
 327                 return 1
 328         fi
 329         echo "$merge_tool"
 330 }
 331
 332 get_merge_tool_path () {
 333         # A merge tool has been set, so verify that it's valid.
 334         merge_tool="$1"
 335         if ! valid_tool "$merge_tool"
 336         then
 337                 echo >&2 "Unknown merge tool $merge_tool"
 338                 exit 1
 339         fi
 340         if diff_mode
 341         then
 342                 merge_tool_path=$(git config difftool."$merge_tool".path ||
 343                                   git config mergetool."$merge_tool".path)
 344         else
 345                 merge_tool_path=$(git config mergetool."$merge_tool".path)
 346         fi
 347         if test -z "$merge_tool_path"
 348         then
 349                 merge_tool_path=$(translate_merge_tool_path "$merge_tool")
 350         fi
 351         if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 352                 ! type "$merge_tool_path" >/dev/null 2>&1
 353         then
 354                 echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 355                          "'$merge_tool_path'"
 356                 exit 1
 357         fi
 358         echo "$merge_tool_path"
 359 }
 360
 361 get_merge_tool () {
 362         # Check if a merge tool has been configured
 363         merge_tool=$(get_configured_merge_tool)
 364         # Try to guess an appropriate merge tool if no tool has been set.
 365         if test -z "$merge_tool"
 366         then
 367                 merge_tool=$(guess_merge_tool) || exit
 368         fi
 369         echo "$merge_tool"
 370 }