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