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
 143 setup_tool () {
 144         tool="$1"
 145
 146         # Fallback definitions, to be overridden by tools.
 147         can_merge () {
 148                 return 0
 149         }
 150
 151         can_diff () {
 152                 return 0
 153         }
 154
 155         diff_cmd () {
 156                 return 1
 157         }
 158
 159         merge_cmd () {
 160                 return 1
 161         }
 162
 163         translate_merge_tool_path () {
 164                 echo "$1"
 165         }
 166
 167         list_tool_variants () {
 168                 echo "$tool"
 169         }
 170
 171         # Most tools' exit codes cannot be trusted, so By default we ignore
 172         # their exit code and check the merged file's modification time in
 173         # check_unchanged() to determine whether or not the merge was
 174         # successful.  The return value from run_merge_cmd, by default, is
 175         # determined by check_unchanged().
 176         #
 177         # When a tool's exit code can be trusted then the return value from
 178         # run_merge_cmd is simply the tool's exit code, and check_unchanged()
 179         # is not called.
 180         #
 181         # The return value of exit_code_trustable() tells us whether or not we
 182         # can trust the tool's exit code.
 183         #
 184         # User-defined and built-in tools default to false.
 185         # Built-in tools advertise that their exit code is trustable by
 186         # redefining exit_code_trustable() to true.
 187
 188         exit_code_trustable () {
 189                 false
 190         }
 191
 192         if test -f "$MERGE_TOOLS_DIR/$tool"
 193         then
 194                 . "$MERGE_TOOLS_DIR/$tool"
 195         elif test -f "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 196         then
 197                 . "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 198         else
 199                 setup_user_tool
 200                 return $?
 201         fi
 202
 203         # Now let the user override the default command for the tool.  If
 204         # they have not done so then this will return 1 which we ignore.
 205         setup_user_tool
 206
 207         if ! list_tool_variants | grep -q "^$tool$"
 208         then
 209                 return 1
 210         fi
 211
 212         if merge_mode && ! can_merge
 213         then
 214                 echo "error: '$tool' can not be used to resolve merges" >&2
 215                 return 1
 216         elif diff_mode && ! can_diff
 217         then
 218                 echo "error: '$tool' can only be used to resolve merges" >&2
 219                 return 1
 220         fi
 221         return 0
 222 }
 223
 224 get_merge_tool_cmd () {
 225         merge_tool="$1"
 226         if diff_mode
 227         then
 228                 git config "difftool.$merge_tool.cmd" ||
 229                 git config "mergetool.$merge_tool.cmd"
 230         else
 231                 git config "mergetool.$merge_tool.cmd"
 232         fi
 233 }
 234
 235 trust_exit_code () {
 236         if git config --bool "mergetool.$1.trustExitCode"
 237         then
 238                 :; # OK
 239         elif exit_code_trustable
 240         then
 241                 echo true
 242         else
 243                 echo false
 244         fi
 245 }
 246
 247
 248 # Entry point for running tools
 249 run_merge_tool () {
 250         # If GIT_PREFIX is empty then we cannot use it in tools
 251         # that expect to be able to chdir() to its value.
 252         GIT_PREFIX=${GIT_PREFIX:-.}
 253         export GIT_PREFIX
 254
 255         merge_tool_path=$(get_merge_tool_path "$1") || exit
 256         base_present="$2"
 257
 258         # Bring tool-specific functions into scope
 259         setup_tool "$1" || return 1
 260
 261         if merge_mode
 262         then
 263                 run_merge_cmd "$1"
 264         else
 265                 run_diff_cmd "$1"
 266         fi
 267 }
 268
 269 # Run a either a configured or built-in diff tool
 270 run_diff_cmd () {
 271         diff_cmd "$1"
 272 }
 273
 274 # Run a either a configured or built-in merge tool
 275 run_merge_cmd () {
 276         mergetool_trust_exit_code=$(trust_exit_code "$1")
 277         if test "$mergetool_trust_exit_code" = "true"
 278         then
 279                 merge_cmd "$1"
 280         else
 281                 touch "$BACKUP"
 282                 merge_cmd "$1"
 283                 check_unchanged
 284         fi
 285 }
 286
 287 list_merge_tool_candidates () {
 288         if merge_mode
 289         then
 290                 tools="tortoisemerge"
 291         else
 292                 tools="kompare"
 293         fi
 294         if test -n "$DISPLAY"
 295         then
 296                 if test -n "$GNOME_DESKTOP_SESSION_ID"
 297                 then
 298                         tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 299                 else
 300                         tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 301                 fi
 302                 tools="$tools gvimdiff diffuse diffmerge ecmerge"
 303                 tools="$tools p4merge araxis bc codecompare"
 304                 tools="$tools smerge"
 305         fi
 306         case "${VISUAL:-$EDITOR}" in
 307         *nvim*)
 308                 tools="$tools nvimdiff vimdiff emerge"
 309                 ;;
 310         *vim*)
 311                 tools="$tools vimdiff nvimdiff emerge"
 312                 ;;
 313         *)
 314                 tools="$tools emerge vimdiff nvimdiff"
 315                 ;;
 316         esac
 317 }
 318
 319 show_tool_help () {
 320         tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"
 321
 322         tab='   '
 323         LF='
 324 '
 325         any_shown=no
 326
 327         cmd_name=${TOOL_MODE}tool
 328         config_tools=$({
 329                 diff_mode && list_config_tools difftool "$tab$tab"
 330                 list_config_tools mergetool "$tab$tab"
 331         } | sort)
 332         extra_content=
 333         if test -n "$config_tools"
 334         then
 335                 extra_content="${tab}user-defined:${LF}$config_tools"
 336         fi
 337
 338         show_tool_names 'mode_ok && is_available' "$tab$tab" \
 339                 "$tool_opt may be set to one of the following:" \
 340                 "No suitable tool for 'git $cmd_name --tool=<tool>' found." \
 341                 "$extra_content" &&
 342                 any_shown=yes
 343
 344         show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
 345                 "${LF}The following tools are valid, but not currently available:" &&
 346                 any_shown=yes
 347
 348         if test "$any_shown" = yes
 349         then
 350                 echo
 351                 echo "Some of the tools listed above only work in a windowed"
 352                 echo "environment. If run in a terminal-only session, they will fail."
 353         fi
 354         exit 0
 355 }
 356
 357 guess_merge_tool () {
 358         list_merge_tool_candidates
 359         cat >&2 <<-EOF
 360
 361         This message is displayed because '$TOOL_MODE.tool' is not configured.
 362         See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
 363         'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
 364         $tools
 365         EOF
 366
 367         # Loop over each candidate and stop when a valid merge tool is found.
 368         IFS=' '
 369         for tool in $tools
 370         do
 371                 is_available "$tool" && echo "$tool" && return 0
 372         done
 373
 374         echo >&2 "No known ${TOOL_MODE} tool is available."
 375         return 1
 376 }
 377
 378 get_configured_merge_tool () {
 379         keys=
 380         if diff_mode
 381         then
 382                 if gui_mode
 383                 then
 384                         keys="diff.guitool merge.guitool diff.tool merge.tool"
 385                 else
 386                         keys="diff.tool merge.tool"
 387                 fi
 388         else
 389                 if gui_mode
 390                 then
 391                         keys="merge.guitool merge.tool"
 392                 else
 393                         keys="merge.tool"
 394                 fi
 395         fi
 396
 397         merge_tool=$(
 398                 IFS=' '
 399                 for key in $keys
 400                 do
 401                         selected=$(git config $key)
 402                         if test -n "$selected"
 403                         then
 404                                 echo "$selected"
 405                                 return
 406                         fi
 407                 done)
 408
 409         if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 410         then
 411                 echo >&2 "git config option $TOOL_MODE.${gui_prefix}tool set to unknown tool: $merge_tool"
 412                 echo >&2 "Resetting to default..."
 413                 return 1
 414         fi
 415         echo "$merge_tool"
 416 }
 417
 418 get_merge_tool_path () {
 419         # A merge tool has been set, so verify that it's valid.
 420         merge_tool="$1"
 421         if ! valid_tool "$merge_tool"
 422         then
 423                 echo >&2 "Unknown merge tool $merge_tool"
 424                 exit 1
 425         fi
 426         if diff_mode
 427         then
 428                 merge_tool_path=$(git config difftool."$merge_tool".path ||
 429                                   git config mergetool."$merge_tool".path)
 430         else
 431                 merge_tool_path=$(git config mergetool."$merge_tool".path)
 432         fi
 433         if test -z "$merge_tool_path"
 434         then
 435                 merge_tool_path=$(translate_merge_tool_path "$merge_tool")
 436         fi
 437         if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 438                 ! type "$merge_tool_path" >/dev/null 2>&1
 439         then
 440                 echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 441                          "'$merge_tool_path'"
 442                 exit 1
 443         fi
 444         echo "$merge_tool_path"
 445 }
 446
 447 get_merge_tool () {
 448         is_guessed=false
 449         # Check if a merge tool has been configured
 450         merge_tool=$(get_configured_merge_tool)
 451         # Try to guess an appropriate merge tool if no tool has been set.
 452         if test -z "$merge_tool"
 453         then
 454                 merge_tool=$(guess_merge_tool) || exit
 455                 is_guessed=true
 456         fi
 457         echo "$merge_tool"
 458         test "$is_guessed" = false
 459 }
 460
 461 mergetool_find_win32_cmd () {
 462         executable=$1
 463         sub_directory=$2
 464
 465         # Use $executable if it exists in $PATH
 466         if type -p "$executable" >/dev/null 2>&1
 467         then
 468                 printf '%s' "$executable"
 469                 return
 470         fi
 471
 472         # Look for executable in the typical locations
 473         for directory in $(env | grep -Ei '^PROGRAM(FILES(\(X86\))?|W6432)=' |
 474                 cut -d '=' -f 2- | sort -u)
 475         do
 476                 if test -n "$directory" && test -x "$directory/$sub_directory/$executable"
 477                 then
 478                         printf '%s' "$directory/$sub_directory/$executable"
 479                         return
 480                 fi
 481         done
 482
 483         printf '%s' "$executable"
 484 }