git-mergetool--lib.shon commit mergetool: run prompt only if guessed tool (4ecc63d)
   1# git-mergetool--lib is a shell library for common merge tool functions
   2
   3: ${MERGE_TOOLS_DIR=$(git --exec-path)/mergetools}
   4
   5mode_ok () {
   6        if diff_mode
   7        then
   8                can_diff
   9        elif merge_mode
  10        then
  11                can_merge
  12        else
  13                false
  14        fi
  15}
  16
  17is_available () {
  18        merge_tool_path=$(translate_merge_tool_path "$1") &&
  19        type "$merge_tool_path" >/dev/null 2>&1
  20}
  21
  22list_config_tools () {
  23        section=$1
  24        line_prefix=${2:-}
  25
  26        git config --get-regexp $section'\..*\.cmd' |
  27        while read -r key value
  28        do
  29                toolname=${key#$section.}
  30                toolname=${toolname%.cmd}
  31
  32                printf "%s%s\n" "$line_prefix" "$toolname"
  33        done
  34}
  35
  36show_tool_names () {
  37        condition=${1:-true} per_line_prefix=${2:-} preamble=${3:-}
  38        not_found_msg=${4:-}
  39        extra_content=${5:-}
  40
  41        shown_any=
  42        ( cd "$MERGE_TOOLS_DIR" && ls ) | {
  43                while read toolname
  44                do
  45                        if setup_tool "$toolname" 2>/dev/null &&
  46                                (eval "$condition" "$toolname")
  47                        then
  48                                if test -n "$preamble"
  49                                then
  50                                        printf "%s\n" "$preamble"
  51                                        preamble=
  52                                fi
  53                                shown_any=yes
  54                                printf "%s%s\n" "$per_line_prefix" "$toolname"
  55                        fi
  56                done
  57
  58                if test -n "$extra_content"
  59                then
  60                        if test -n "$preamble"
  61                        then
  62                                # Note: no '\n' here since we don't want a
  63                                # blank line if there is no initial content.
  64                                printf "%s" "$preamble"
  65                                preamble=
  66                        fi
  67                        shown_any=yes
  68                        printf "\n%s\n" "$extra_content"
  69                fi
  70
  71                if test -n "$preamble" && test -n "$not_found_msg"
  72                then
  73                        printf "%s\n" "$not_found_msg"
  74                fi
  75
  76                test -n "$shown_any"
  77        }
  78}
  79
  80diff_mode() {
  81        test "$TOOL_MODE" = diff
  82}
  83
  84merge_mode() {
  85        test "$TOOL_MODE" = merge
  86}
  87
  88translate_merge_tool_path () {
  89        echo "$1"
  90}
  91
  92check_unchanged () {
  93        if test "$MERGED" -nt "$BACKUP"
  94        then
  95                status=0
  96        else
  97                while true
  98                do
  99                        echo "$MERGED seems unchanged."
 100                        printf "Was the merge successful? [y/n] "
 101                        read answer || return 1
 102                        case "$answer" in
 103                        y*|Y*) status=0; break ;;
 104                        n*|N*) status=1; break ;;
 105                        esac
 106                done
 107        fi
 108}
 109
 110valid_tool () {
 111        setup_tool "$1" && return 0
 112        cmd=$(get_merge_tool_cmd "$1")
 113        test -n "$cmd"
 114}
 115
 116setup_user_tool () {
 117        merge_tool_cmd=$(get_merge_tool_cmd "$tool")
 118        test -n "$merge_tool_cmd" || return 1
 119
 120        diff_cmd () {
 121                ( eval $merge_tool_cmd )
 122                status=$?
 123                return $status
 124        }
 125
 126        merge_cmd () {
 127                trust_exit_code=$(git config --bool \
 128                        "mergetool.$1.trustExitCode" || echo false)
 129                if test "$trust_exit_code" = "false"
 130                then
 131                        touch "$BACKUP"
 132                        ( eval $merge_tool_cmd )
 133                        status=$?
 134                        check_unchanged
 135                else
 136                        ( eval $merge_tool_cmd )
 137                        status=$?
 138                fi
 139                return $status
 140        }
 141}
 142
 143setup_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                status=1
 157                return $status
 158        }
 159
 160        merge_cmd () {
 161                status=1
 162                return $status
 163        }
 164
 165        translate_merge_tool_path () {
 166                echo "$1"
 167        }
 168
 169        if ! test -f "$MERGE_TOOLS_DIR/$tool"
 170        then
 171                setup_user_tool
 172                return $?
 173        fi
 174
 175        # Load the redefined functions
 176        . "$MERGE_TOOLS_DIR/$tool"
 177        # Now let the user override the default command for the tool.  If
 178        # they have not done so then this will return 1 which we ignore.
 179        setup_user_tool
 180
 181        if merge_mode && ! can_merge
 182        then
 183                echo "error: '$tool' can not be used to resolve merges" >&2
 184                return 1
 185        elif diff_mode && ! can_diff
 186        then
 187                echo "error: '$tool' can only be used to resolve merges" >&2
 188                return 1
 189        fi
 190        return 0
 191}
 192
 193get_merge_tool_cmd () {
 194        merge_tool="$1"
 195        if diff_mode
 196        then
 197                git config "difftool.$merge_tool.cmd" ||
 198                git config "mergetool.$merge_tool.cmd"
 199        else
 200                git config "mergetool.$merge_tool.cmd"
 201        fi
 202}
 203
 204# Entry point for running tools
 205run_merge_tool () {
 206        # If GIT_PREFIX is empty then we cannot use it in tools
 207        # that expect to be able to chdir() to its value.
 208        GIT_PREFIX=${GIT_PREFIX:-.}
 209        export GIT_PREFIX
 210
 211        merge_tool_path=$(get_merge_tool_path "$1") || exit
 212        base_present="$2"
 213        status=0
 214
 215        # Bring tool-specific functions into scope
 216        setup_tool "$1" || return 1
 217
 218        if merge_mode
 219        then
 220                run_merge_cmd "$1"
 221        else
 222                run_diff_cmd "$1"
 223        fi
 224        return $status
 225}
 226
 227# Run a either a configured or built-in diff tool
 228run_diff_cmd () {
 229        diff_cmd "$1"
 230}
 231
 232# Run a either a configured or built-in merge tool
 233run_merge_cmd () {
 234        merge_cmd "$1"
 235}
 236
 237list_merge_tool_candidates () {
 238        if merge_mode
 239        then
 240                tools="tortoisemerge"
 241        else
 242                tools="kompare"
 243        fi
 244        if test -n "$DISPLAY"
 245        then
 246                if test -n "$GNOME_DESKTOP_SESSION_ID"
 247                then
 248                        tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 249                else
 250                        tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 251                fi
 252                tools="$tools gvimdiff diffuse diffmerge ecmerge"
 253                tools="$tools p4merge araxis bc3 codecompare"
 254        fi
 255        case "${VISUAL:-$EDITOR}" in
 256        *vim*)
 257                tools="$tools vimdiff emerge"
 258                ;;
 259        *)
 260                tools="$tools emerge vimdiff"
 261                ;;
 262        esac
 263}
 264
 265show_tool_help () {
 266        tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"
 267
 268        tab='   '
 269        LF='
 270'
 271        any_shown=no
 272
 273        cmd_name=${TOOL_MODE}tool
 274        config_tools=$({
 275                diff_mode && list_config_tools difftool "$tab$tab"
 276                list_config_tools mergetool "$tab$tab"
 277        } | sort)
 278        extra_content=
 279        if test -n "$config_tools"
 280        then
 281                extra_content="${tab}user-defined:${LF}$config_tools"
 282        fi
 283
 284        show_tool_names 'mode_ok && is_available' "$tab$tab" \
 285                "$tool_opt may be set to one of the following:" \
 286                "No suitable tool for 'git $cmd_name --tool=<tool>' found." \
 287                "$extra_content" &&
 288                any_shown=yes
 289
 290        show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
 291                "${LF}The following tools are valid, but not currently available:" &&
 292                any_shown=yes
 293
 294        if test "$any_shown" = yes
 295        then
 296                echo
 297                echo "Some of the tools listed above only work in a windowed"
 298                echo "environment. If run in a terminal-only session, they will fail."
 299        fi
 300        exit 0
 301}
 302
 303guess_merge_tool () {
 304        list_merge_tool_candidates
 305        cat >&2 <<-EOF
 306
 307        This message is displayed because '$TOOL_MODE.tool' is not configured.
 308        See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
 309        'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
 310        $tools
 311        EOF
 312
 313        # Loop over each candidate and stop when a valid merge tool is found.
 314        for tool in $tools
 315        do
 316                is_available "$tool" && echo "$tool" && return 0
 317        done
 318
 319        echo >&2 "No known ${TOOL_MODE} tool is available."
 320        return 1
 321}
 322
 323get_configured_merge_tool () {
 324        # Diff mode first tries diff.tool and falls back to merge.tool.
 325        # Merge mode only checks merge.tool
 326        if diff_mode
 327        then
 328                merge_tool=$(git config diff.tool || git config merge.tool)
 329        else
 330                merge_tool=$(git config merge.tool)
 331        fi
 332        if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 333        then
 334                echo >&2 "git config option $TOOL_MODE.tool set to unknown tool: $merge_tool"
 335                echo >&2 "Resetting to default..."
 336                return 1
 337        fi
 338        echo "$merge_tool"
 339}
 340
 341get_merge_tool_path () {
 342        # A merge tool has been set, so verify that it's valid.
 343        merge_tool="$1"
 344        if ! valid_tool "$merge_tool"
 345        then
 346                echo >&2 "Unknown merge tool $merge_tool"
 347                exit 1
 348        fi
 349        if diff_mode
 350        then
 351                merge_tool_path=$(git config difftool."$merge_tool".path ||
 352                                  git config mergetool."$merge_tool".path)
 353        else
 354                merge_tool_path=$(git config mergetool."$merge_tool".path)
 355        fi
 356        if test -z "$merge_tool_path"
 357        then
 358                merge_tool_path=$(translate_merge_tool_path "$merge_tool")
 359        fi
 360        if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 361                ! type "$merge_tool_path" >/dev/null 2>&1
 362        then
 363                echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 364                         "'$merge_tool_path'"
 365                exit 1
 366        fi
 367        echo "$merge_tool_path"
 368}
 369
 370get_merge_tool () {
 371        # Check if a merge tool has been configured
 372        merge_tool=$(get_configured_merge_tool)
 373        # Try to guess an appropriate merge tool if no tool has been set.
 374        if test -z "$merge_tool"
 375        then
 376                merge_tool=$(guess_merge_tool) || exit
 377        fi
 378        echo "$merge_tool"
 379}