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