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 IFS='
   6 '
   7
   8 mode_ok () {
   9         if diff_mode
  10         then
  11                 can_diff
  12         elif merge_mode
  13         then
  14                 can_merge
  15         else
  16                 false
  17         fi
  18 }
  19
  20 is_available () {
  21         merge_tool_path=$(translate_merge_tool_path "$1") &&
  22         type "$merge_tool_path" >/dev/null 2>&1
  23 }
  24
  25 list_config_tools () {
  26         section=$1
  27         line_prefix=${2:-}
  28
  29         git config --get-regexp $section'\..*\.cmd' |
  30         while read -r key value
  31         do
  32                 toolname=${key#$section.}
  33                 toolname=${toolname%.cmd}
  34
  35                 printf "%s%s\n" "$line_prefix" "$toolname"
  36         done
  37 }
  38
  39 show_tool_names () {
  40         condition=${1:-true} per_line_prefix=${2:-} preamble=${3:-}
  41         not_found_msg=${4:-}
  42         extra_content=${5:-}
  43
  44         shown_any=
  45         ( cd "$MERGE_TOOLS_DIR" && ls ) | {
  46                 while read scriptname
  47                 do
  48                         setup_tool "$scriptname" 2>/dev/null
  49                         variants="$variants$(list_tool_variants)\n"
  50                 done
  51                 variants="$(echo "$variants" | sort | uniq)"
  52
  53                 for toolname in $variants
  54                 do
  55                         if setup_tool "$toolname" 2>/dev/null &&
  56                                 (eval "$condition" "$toolname")
  57                         then
  58                                 if test -n "$preamble"
  59                                 then
  60                                         printf "%s\n" "$preamble"
  61                                         preamble=
  62                                 fi
  63                                 shown_any=yes
  64                                 printf "%s%s\n" "$per_line_prefix" "$toolname"
  65                         fi
  66                 done
  67
  68                 if test -n "$extra_content"
  69                 then
  70                         if test -n "$preamble"
  71                         then
  72                                 # Note: no '\n' here since we don't want a
  73                                 # blank line if there is no initial content.
  74                                 printf "%s" "$preamble"
  75                                 preamble=
  76                         fi
  77                         shown_any=yes
  78                         printf "\n%s\n" "$extra_content"
  79                 fi
  80
  81                 if test -n "$preamble" && test -n "$not_found_msg"
  82                 then
  83                         printf "%s\n" "$not_found_msg"
  84                 fi
  85
  86                 test -n "$shown_any"
  87         }
  88 }
  89
  90 diff_mode () {
  91         test "$TOOL_MODE" = diff
  92 }
  93
  94 merge_mode () {
  95         test "$TOOL_MODE" = merge
  96 }
  97
  98 gui_mode () {
  99         test "$GIT_MERGETOOL_GUI" = true
 100 }
 101
 102 translate_merge_tool_path () {
 103         echo "$1"
 104 }
 105
 106 check_unchanged () {
 107         if test "$MERGED" -nt "$BACKUP"
 108         then
 109                 return 0
 110         else
 111                 while true
 112                 do
 113                         echo "$MERGED seems unchanged."
 114                         printf "Was the merge successful [y/n]? "
 115                         read answer || return 1
 116                         case "$answer" in
 117                         y*|Y*) return 0 ;;
 118                         n*|N*) return 1 ;;
 119                         esac
 120                 done
 121         fi
 122 }
 123
 124 valid_tool () {
 125         setup_tool "$1" && return 0
 126         cmd=$(get_merge_tool_cmd "$1")
 127         test -n "$cmd"
 128 }
 129
 130 setup_user_tool () {
 131         merge_tool_cmd=$(get_merge_tool_cmd "$tool")
 132         test -n "$merge_tool_cmd" || return 1
 133
 134         diff_cmd () {
 135                 ( eval $merge_tool_cmd )
 136         }
 137
 138         merge_cmd () {
 139                 ( eval $merge_tool_cmd )
 140         }
 141
 142         list_tool_variants () {
 143                 echo "$tool"
 144         }
 145 }
 146
 147 setup_tool () {
 148         tool="$1"
 149
 150         # Fallback definitions, to be overridden by tools.
 151         can_merge () {
 152                 return 0
 153         }
 154
 155         can_diff () {
 156                 return 0
 157         }
 158
 159         diff_cmd () {
 160                 return 1
 161         }
 162
 163         merge_cmd () {
 164                 return 1
 165         }
 166
 167         translate_merge_tool_path () {
 168                 echo "$1"
 169         }
 170
 171         list_tool_variants () {
 172                 echo "$tool"
 173         }
 174
 175         # Most tools' exit codes cannot be trusted, so By default we ignore
 176         # their exit code and check the merged file's modification time in
 177         # check_unchanged() to determine whether or not the merge was
 178         # successful.  The return value from run_merge_cmd, by default, is
 179         # determined by check_unchanged().
 180         #
 181         # When a tool's exit code can be trusted then the return value from
 182         # run_merge_cmd is simply the tool's exit code, and check_unchanged()
 183         # is not called.
 184         #
 185         # The return value of exit_code_trustable() tells us whether or not we
 186         # can trust the tool's exit code.
 187         #
 188         # User-defined and built-in tools default to false.
 189         # Built-in tools advertise that their exit code is trustable by
 190         # redefining exit_code_trustable() to true.
 191
 192         exit_code_trustable () {
 193                 false
 194         }
 195
 196         if test -f "$MERGE_TOOLS_DIR/$tool"
 197         then
 198                 . "$MERGE_TOOLS_DIR/$tool"
 199         elif test -f "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 200         then
 201                 . "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 202         else
 203                 setup_user_tool
 204                 return $?
 205         fi
 206
 207         # Now let the user override the default command for the tool.  If
 208         # they have not done so then this will return 1 which we ignore.
 209         setup_user_tool
 210
 211         if ! list_tool_variants | grep -q "^$tool$"
 212         then
 213                 return 1
 214         fi
 215
 216         if merge_mode && ! can_merge
 217         then
 218                 echo "error: '$tool' can not be used to resolve merges" >&2
 219                 return 1
 220         elif diff_mode && ! can_diff
 221         then
 222                 echo "error: '$tool' can only be used to resolve merges" >&2
 223                 return 1
 224         fi
 225         return 0
 226 }
 227
 228 get_merge_tool_cmd () {
 229         merge_tool="$1"
 230         if diff_mode
 231         then
 232                 git config "difftool.$merge_tool.cmd" ||
 233                 git config "mergetool.$merge_tool.cmd"
 234         else
 235                 git config "mergetool.$merge_tool.cmd"
 236         fi
 237 }
 238
 239 trust_exit_code () {
 240         if git config --bool "mergetool.$1.trustExitCode"
 241         then
 242                 :; # OK
 243         elif exit_code_trustable
 244         then
 245                 echo true
 246         else
 247                 echo false
 248         fi
 249 }
 250
 251
 252 # Entry point for running tools
 253 run_merge_tool () {
 254         # If GIT_PREFIX is empty then we cannot use it in tools
 255         # that expect to be able to chdir() to its value.
 256         GIT_PREFIX=${GIT_PREFIX:-.}
 257         export GIT_PREFIX
 258
 259         merge_tool_path=$(get_merge_tool_path "$1") || exit
 260         base_present="$2"
 261
 262         # Bring tool-specific functions into scope
 263         setup_tool "$1" || return 1
 264
 265         if merge_mode
 266         then
 267                 run_merge_cmd "$1"
 268         else
 269                 run_diff_cmd "$1"
 270         fi
 271 }
 272
 273 # Run a either a configured or built-in diff tool
 274 run_diff_cmd () {
 275         diff_cmd "$1"
 276 }
 277
 278 # Run a either a configured or built-in merge tool
 279 run_merge_cmd () {
 280         mergetool_trust_exit_code=$(trust_exit_code "$1")
 281         if test "$mergetool_trust_exit_code" = "true"
 282         then
 283                 merge_cmd "$1"
 284         else
 285                 touch "$BACKUP"
 286                 merge_cmd "$1"
 287                 check_unchanged
 288         fi
 289 }
 290
 291 list_merge_tool_candidates () {
 292         if merge_mode
 293         then
 294                 tools="tortoisemerge"
 295         else
 296                 tools="kompare"
 297         fi
 298         if test -n "$DISPLAY"
 299         then
 300                 if test -n "$GNOME_DESKTOP_SESSION_ID"
 301                 then
 302                         tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 303                 else
 304                         tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 305                 fi
 306                 tools="$tools gvimdiff diffuse diffmerge ecmerge"
 307                 tools="$tools p4merge araxis bc codecompare"
 308                 tools="$tools smerge"
 309         fi
 310         case "${VISUAL:-$EDITOR}" in
 311         *nvim*)
 312                 tools="$tools nvimdiff vimdiff emerge"
 313                 ;;
 314         *vim*)
 315                 tools="$tools vimdiff nvimdiff emerge"
 316                 ;;
 317         *)
 318                 tools="$tools emerge vimdiff nvimdiff"
 319                 ;;
 320         esac
 321 }
 322
 323 show_tool_help () {
 324         tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"
 325
 326         tab='   '
 327         LF='
 328 '
 329         any_shown=no
 330
 331         cmd_name=${TOOL_MODE}tool
 332         config_tools=$({
 333                 diff_mode && list_config_tools difftool "$tab$tab"
 334                 list_config_tools mergetool "$tab$tab"
 335         } | sort)
 336         extra_content=
 337         if test -n "$config_tools"
 338         then
 339                 extra_content="${tab}user-defined:${LF}$config_tools"
 340         fi
 341
 342         show_tool_names 'mode_ok && is_available' "$tab$tab" \
 343                 "$tool_opt may be set to one of the following:" \
 344                 "No suitable tool for 'git $cmd_name --tool=<tool>' found." \
 345                 "$extra_content" &&
 346                 any_shown=yes
 347
 348         show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
 349                 "${LF}The following tools are valid, but not currently available:" &&
 350                 any_shown=yes
 351
 352         if test "$any_shown" = yes
 353         then
 354                 echo
 355                 echo "Some of the tools listed above only work in a windowed"
 356                 echo "environment. If run in a terminal-only session, they will fail."
 357         fi
 358         exit 0
 359 }
 360
 361 guess_merge_tool () {
 362         list_merge_tool_candidates
 363         cat >&2 <<-EOF
 364
 365         This message is displayed because '$TOOL_MODE.tool' is not configured.
 366         See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
 367         'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
 368         $tools
 369         EOF
 370
 371         # Loop over each candidate and stop when a valid merge tool is found.
 372         IFS=' '
 373         for tool in $tools
 374         do
 375                 is_available "$tool" && echo "$tool" && return 0
 376         done
 377
 378         echo >&2 "No known ${TOOL_MODE} tool is available."
 379         return 1
 380 }
 381
 382 get_configured_merge_tool () {
 383         keys=
 384         if diff_mode
 385         then
 386                 if gui_mode
 387                 then
 388                         keys="diff.guitool merge.guitool diff.tool merge.tool"
 389                 else
 390                         keys="diff.tool merge.tool"
 391                 fi
 392         else
 393                 if gui_mode
 394                 then
 395                         keys="merge.guitool merge.tool"
 396                 else
 397                         keys="merge.tool"
 398                 fi
 399         fi
 400
 401         merge_tool=$(
 402                 IFS=' '
 403                 for key in $keys
 404                 do
 405                         selected=$(git config $key)
 406                         if test -n "$selected"
 407                         then
 408                                 echo "$selected"
 409                                 return
 410                         fi
 411                 done)
 412
 413         if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 414         then
 415                 echo >&2 "git config option $TOOL_MODE.${gui_prefix}tool set to unknown tool: $merge_tool"
 416                 echo >&2 "Resetting to default..."
 417                 return 1
 418         fi
 419         echo "$merge_tool"
 420 }
 421
 422 get_merge_tool_path () {
 423         # A merge tool has been set, so verify that it's valid.
 424         merge_tool="$1"
 425         if ! valid_tool "$merge_tool"
 426         then
 427                 echo >&2 "Unknown merge tool $merge_tool"
 428                 exit 1
 429         fi
 430         if diff_mode
 431         then
 432                 merge_tool_path=$(git config difftool."$merge_tool".path ||
 433                                   git config mergetool."$merge_tool".path)
 434         else
 435                 merge_tool_path=$(git config mergetool."$merge_tool".path)
 436         fi
 437         if test -z "$merge_tool_path"
 438         then
 439                 merge_tool_path=$(translate_merge_tool_path "$merge_tool")
 440         fi
 441         if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 442                 ! type "$merge_tool_path" >/dev/null 2>&1
 443         then
 444                 echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 445                          "'$merge_tool_path'"
 446                 exit 1
 447         fi
 448         echo "$merge_tool_path"
 449 }
 450
 451 get_merge_tool () {
 452         is_guessed=false
 453         # Check if a merge tool has been configured
 454         merge_tool=$(get_configured_merge_tool)
 455         # Try to guess an appropriate merge tool if no tool has been set.
 456         if test -z "$merge_tool"
 457         then
 458                 merge_tool=$(guess_merge_tool) || exit
 459                 is_guessed=true
 460         fi
 461         echo "$merge_tool"
 462         test "$is_guessed" = false
 463 }
 464
 465 mergetool_find_win32_cmd () {
 466         executable=$1
 467         sub_directory=$2
 468
 469         # Use $executable if it exists in $PATH
 470         if type -p "$executable" >/dev/null 2>&1
 471         then
 472                 printf '%s' "$executable"
 473                 return
 474         fi
 475
 476         # Look for executable in the typical locations
 477         for directory in $(env | grep -Ei '^PROGRAM(FILES(\(X86\))?|W6432)=' |
 478                 cut -d '=' -f 2- | sort -u)
 479         do
 480                 if test -n "$directory" && test -x "$directory/$sub_directory/$executable"
 481                 then
 482                         printf '%s' "$directory/$sub_directory/$executable"
 483                         return
 484                 fi
 485         done
 486
 487         printf '%s' "$executable"
 488 }