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 "$scriptname" 2>/dev/null
  49                         # We need an actual line feed here
  50                         variants="$variants
  51 $(list_tool_variants)"
  52                 done
  53                 variants="$(echo "$variants" | sort -u)"
  54
  55                 for toolname in $variants
  56                 do
  57                         if setup_tool "$toolname" 2>/dev/null &&
  58                                 (eval "$condition" "$toolname")
  59                         then
  60                                 if test -n "$preamble"
  61                                 then
  62                                         printf "%s\n" "$preamble"
  63                                         preamble=
  64                                 fi
  65                                 shown_any=yes
  66                                 printf "%s%s\n" "$per_line_prefix" "$toolname"
  67                         fi
  68                 done
  69
  70                 if test -n "$extra_content"
  71                 then
  72                         if test -n "$preamble"
  73                         then
  74                                 # Note: no '\n' here since we don't want a
  75                                 # blank line if there is no initial content.
  76                                 printf "%s" "$preamble"
  77                                 preamble=
  78                         fi
  79                         shown_any=yes
  80                         printf "\n%s\n" "$extra_content"
  81                 fi
  82
  83                 if test -n "$preamble" && test -n "$not_found_msg"
  84                 then
  85                         printf "%s\n" "$not_found_msg"
  86                 fi
  87
  88                 test -n "$shown_any"
  89         }
  90 }
  91
  92 diff_mode () {
  93         test "$TOOL_MODE" = diff
  94 }
  95
  96 merge_mode () {
  97         test "$TOOL_MODE" = merge
  98 }
  99
 100 gui_mode () {
 101         test "$GIT_MERGETOOL_GUI" = true
 102 }
 103
 104 translate_merge_tool_path () {
 105         echo "$1"
 106 }
 107
 108 check_unchanged () {
 109         if test "$MERGED" -nt "$BACKUP"
 110         then
 111                 return 0
 112         else
 113                 while true
 114                 do
 115                         echo "$MERGED seems unchanged."
 116                         printf "Was the merge successful [y/n]? "
 117                         read answer || return 1
 118                         case "$answer" in
 119                         y*|Y*) return 0 ;;
 120                         n*|N*) return 1 ;;
 121                         esac
 122                 done
 123         fi
 124 }
 125
 126 valid_tool () {
 127         setup_tool "$1" && return 0
 128         cmd=$(get_merge_tool_cmd "$1")
 129         test -n "$cmd"
 130 }
 131
 132 setup_user_tool () {
 133         merge_tool_cmd=$(get_merge_tool_cmd "$tool")
 134         test -n "$merge_tool_cmd" || return 1
 135
 136         diff_cmd () {
 137                 ( eval $merge_tool_cmd )
 138         }
 139
 140         merge_cmd () {
 141                 ( eval $merge_tool_cmd )
 142         }
 143
 144         list_tool_variants () {
 145                 echo "$tool"
 146         }
 147 }
 148
 149 setup_tool () {
 150         tool="$1"
 151
 152         # Fallback definitions, to be overridden by tools.
 153         can_merge () {
 154                 return 0
 155         }
 156
 157         can_diff () {
 158                 return 0
 159         }
 160
 161         diff_cmd () {
 162                 return 1
 163         }
 164
 165         merge_cmd () {
 166                 return 1
 167         }
 168
 169         hide_resolved_enabled () {
 170                 return 0
 171         }
 172
 173         translate_merge_tool_path () {
 174                 echo "$1"
 175         }
 176
 177         list_tool_variants () {
 178                 echo "$tool"
 179         }
 180
 181         # Most tools' exit codes cannot be trusted, so By default we ignore
 182         # their exit code and check the merged file's modification time in
 183         # check_unchanged() to determine whether or not the merge was
 184         # successful.  The return value from run_merge_cmd, by default, is
 185         # determined by check_unchanged().
 186         #
 187         # When a tool's exit code can be trusted then the return value from
 188         # run_merge_cmd is simply the tool's exit code, and check_unchanged()
 189         # is not called.
 190         #
 191         # The return value of exit_code_trustable() tells us whether or not we
 192         # can trust the tool's exit code.
 193         #
 194         # User-defined and built-in tools default to false.
 195         # Built-in tools advertise that their exit code is trustable by
 196         # redefining exit_code_trustable() to true.
 197
 198         exit_code_trustable () {
 199                 false
 200         }
 201
 202         if test -f "$MERGE_TOOLS_DIR/$tool"
 203         then
 204                 . "$MERGE_TOOLS_DIR/$tool"
 205         elif test -f "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 206         then
 207                 . "$MERGE_TOOLS_DIR/${tool%[0-9]}"
 208         else
 209                 setup_user_tool
 210                 return $?
 211         fi
 212
 213         # Now let the user override the default command for the tool.  If
 214         # they have not done so then this will return 1 which we ignore.
 215         setup_user_tool
 216
 217         if ! list_tool_variants | grep -q "^$tool$"
 218         then
 219                 return 1
 220         fi
 221
 222         if merge_mode && ! can_merge
 223         then
 224                 echo "error: '$tool' can not be used to resolve merges" >&2
 225                 return 1
 226         elif diff_mode && ! can_diff
 227         then
 228                 echo "error: '$tool' can only be used to resolve merges" >&2
 229                 return 1
 230         fi
 231         return 0
 232 }
 233
 234 get_merge_tool_cmd () {
 235         merge_tool="$1"
 236         if diff_mode
 237         then
 238                 git config "difftool.$merge_tool.cmd" ||
 239                 git config "mergetool.$merge_tool.cmd"
 240         else
 241                 git config "mergetool.$merge_tool.cmd"
 242         fi
 243 }
 244
 245 trust_exit_code () {
 246         if git config --bool "mergetool.$1.trustExitCode"
 247         then
 248                 :; # OK
 249         elif exit_code_trustable
 250         then
 251                 echo true
 252         else
 253                 echo false
 254         fi
 255 }
 256
 257 initialize_merge_tool () {
 258         # Bring tool-specific functions into scope
 259         setup_tool "$1" || return 1
 260 }
 261
 262 # Entry point for running tools
 263 run_merge_tool () {
 264         # If GIT_PREFIX is empty then we cannot use it in tools
 265         # that expect to be able to chdir() to its value.
 266         GIT_PREFIX=${GIT_PREFIX:-.}
 267         export GIT_PREFIX
 268
 269         merge_tool_path=$(get_merge_tool_path "$1") || exit
 270         base_present="$2"
 271
 272         if merge_mode
 273         then
 274                 run_merge_cmd "$1"
 275         else
 276                 run_diff_cmd "$1"
 277         fi
 278 }
 279
 280 # Run a either a configured or built-in diff tool
 281 run_diff_cmd () {
 282         diff_cmd "$1"
 283 }
 284
 285 # Run a either a configured or built-in merge tool
 286 run_merge_cmd () {
 287         mergetool_trust_exit_code=$(trust_exit_code "$1")
 288         if test "$mergetool_trust_exit_code" = "true"
 289         then
 290                 merge_cmd "$1"
 291         else
 292                 touch "$BACKUP"
 293                 merge_cmd "$1"
 294                 check_unchanged
 295         fi
 296 }
 297
 298 list_merge_tool_candidates () {
 299         if merge_mode
 300         then
 301                 tools="tortoisemerge"
 302         else
 303                 tools="kompare"
 304         fi
 305         if test -n "$DISPLAY"
 306         then
 307                 if test -n "$GNOME_DESKTOP_SESSION_ID"
 308                 then
 309                         tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 310                 else
 311                         tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 312                 fi
 313                 tools="$tools gvimdiff diffuse diffmerge ecmerge"
 314                 tools="$tools p4merge araxis bc codecompare"
 315                 tools="$tools smerge"
 316         fi
 317         case "${VISUAL:-$EDITOR}" in
 318         *nvim*)
 319                 tools="$tools nvimdiff vimdiff emerge"
 320                 ;;
 321         *vim*)
 322                 tools="$tools vimdiff nvimdiff emerge"
 323                 ;;
 324         *)
 325                 tools="$tools emerge vimdiff nvimdiff"
 326                 ;;
 327         esac
 328 }
 329
 330 show_tool_help () {
 331         tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"
 332
 333         tab='   '
 334         LF='
 335 '
 336         any_shown=no
 337
 338         cmd_name=${TOOL_MODE}tool
 339         config_tools=$({
 340                 diff_mode && list_config_tools difftool "$tab$tab"
 341                 list_config_tools mergetool "$tab$tab"
 342         } | sort)
 343         extra_content=
 344         if test -n "$config_tools"
 345         then
 346                 extra_content="${tab}user-defined:${LF}$config_tools"
 347         fi
 348
 349         show_tool_names 'mode_ok && is_available' "$tab$tab" \
 350                 "$tool_opt may be set to one of the following:" \
 351                 "No suitable tool for 'git $cmd_name --tool=<tool>' found." \
 352                 "$extra_content" &&
 353                 any_shown=yes
 354
 355         show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
 356                 "${LF}The following tools are valid, but not currently available:" &&
 357                 any_shown=yes
 358
 359         if test "$any_shown" = yes
 360         then
 361                 echo
 362                 echo "Some of the tools listed above only work in a windowed"
 363                 echo "environment. If run in a terminal-only session, they will fail."
 364         fi
 365         exit 0
 366 }
 367
 368 guess_merge_tool () {
 369         list_merge_tool_candidates
 370         cat >&2 <<-EOF
 371
 372         This message is displayed because '$TOOL_MODE.tool' is not configured.
 373         See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
 374         'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
 375         $tools
 376         EOF
 377
 378         # Loop over each candidate and stop when a valid merge tool is found.
 379         IFS=' '
 380         for tool in $tools
 381         do
 382                 is_available "$tool" && echo "$tool" && return 0
 383         done
 384
 385         echo >&2 "No known ${TOOL_MODE} tool is available."
 386         return 1
 387 }
 388
 389 get_configured_merge_tool () {
 390         keys=
 391         if diff_mode
 392         then
 393                 if gui_mode
 394                 then
 395                         keys="diff.guitool merge.guitool diff.tool merge.tool"
 396                 else
 397                         keys="diff.tool merge.tool"
 398                 fi
 399         else
 400                 if gui_mode
 401                 then
 402                         keys="merge.guitool merge.tool"
 403                 else
 404                         keys="merge.tool"
 405                 fi
 406         fi
 407
 408         merge_tool=$(
 409                 IFS=' '
 410                 for key in $keys
 411                 do
 412                         selected=$(git config $key)
 413                         if test -n "$selected"
 414                         then
 415                                 echo "$selected"
 416                                 return
 417                         fi
 418                 done)
 419
 420         if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 421         then
 422                 echo >&2 "git config option $TOOL_MODE.${gui_prefix}tool set to unknown tool: $merge_tool"
 423                 echo >&2 "Resetting to default..."
 424                 return 1
 425         fi
 426         echo "$merge_tool"
 427 }
 428
 429 get_merge_tool_path () {
 430         # A merge tool has been set, so verify that it's valid.
 431         merge_tool="$1"
 432         if ! valid_tool "$merge_tool"
 433         then
 434                 echo >&2 "Unknown merge tool $merge_tool"
 435                 exit 1
 436         fi
 437         if diff_mode
 438         then
 439                 merge_tool_path=$(git config difftool."$merge_tool".path ||
 440                                   git config mergetool."$merge_tool".path)
 441         else
 442                 merge_tool_path=$(git config mergetool."$merge_tool".path)
 443         fi
 444         if test -z "$merge_tool_path"
 445         then
 446                 merge_tool_path=$(translate_merge_tool_path "$merge_tool")
 447         fi
 448         if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 449                 ! type "$merge_tool_path" >/dev/null 2>&1
 450         then
 451                 echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 452                          "'$merge_tool_path'"
 453                 exit 1
 454         fi
 455         echo "$merge_tool_path"
 456 }
 457
 458 get_merge_tool () {
 459         is_guessed=false
 460         # Check if a merge tool has been configured
 461         merge_tool=$(get_configured_merge_tool)
 462         # Try to guess an appropriate merge tool if no tool has been set.
 463         if test -z "$merge_tool"
 464         then
 465                 merge_tool=$(guess_merge_tool) || exit
 466                 is_guessed=true
 467         fi
 468         echo "$merge_tool"
 469         test "$is_guessed" = false
 470 }
 471
 472 mergetool_find_win32_cmd () {
 473         executable=$1
 474         sub_directory=$2
 475
 476         # Use $executable if it exists in $PATH
 477         if type -p "$executable" >/dev/null 2>&1
 478         then
 479                 printf '%s' "$executable"
 480                 return
 481         fi
 482
 483         # Look for executable in the typical locations
 484         for directory in $(env | grep -Ei '^PROGRAM(FILES(\(X86\))?|W6432)=' |
 485                 cut -d '=' -f 2- | sort -u)
 486         do
 487                 if test -n "$directory" && test -x "$directory/$sub_directory/$executable"
 488                 then
 489                         printf '%s' "$directory/$sub_directory/$executable"
 490                         return
 491                 fi
 492         done
 493
 494         printf '%s' "$executable"
 495 }