refs.c: add repo_dwim_ref()

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index 92adcc0d0785f8b78fce2c49bbcc40e49020ee24..83bf52494cd26437eaa3c755c3359951937f1ab2 100644 (file)
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -125,16 +125,7 @@ setup_user_tool () {
        }
 
        merge_cmd () {
-               trust_exit_code=$(git config --bool \
-                       "mergetool.$1.trustExitCode" || echo false)
-               if test "$trust_exit_code" = "false"
-               then
-                       touch "$BACKUP"
-                       ( eval $merge_tool_cmd )
-                       check_unchanged
-               else
-                       ( eval $merge_tool_cmd )
-               fi
+               ( eval $merge_tool_cmd )
        }
 }
 
@@ -162,6 +153,28 @@ setup_tool () {
                echo "$1"
        }
 
+       # Most tools' exit codes cannot be trusted, so By default we ignore
+       # their exit code and check the merged file's modification time in
+       # check_unchanged() to determine whether or not the merge was
+       # successful.  The return value from run_merge_cmd, by default, is
+       # determined by check_unchanged().
+       #
+       # When a tool's exit code can be trusted then the return value from
+       # run_merge_cmd is simply the tool's exit code, and check_unchanged()
+       # is not called.
+       #
+       # The return value of exit_code_trustable() tells us whether or not we
+       # can trust the tool's exit code.
+       #
+       # User-defined and built-in tools default to false.
+       # Built-in tools advertise that their exit code is trustable by
+       # redefining exit_code_trustable() to true.
+
+       exit_code_trustable () {
+               false
+       }
+
+
        if ! test -f "$MERGE_TOOLS_DIR/$tool"
        then
                setup_user_tool
@@ -197,6 +210,19 @@ get_merge_tool_cmd () {
        fi
 }
 
+trust_exit_code () {
+       if git config --bool "mergetool.$1.trustExitCode"
+       then
+               :; # OK
+       elif exit_code_trustable
+       then
+               echo true
+       else
+               echo false
+       fi
+}
+
+
 # Entry point for running tools
 run_merge_tool () {
        # If GIT_PREFIX is empty then we cannot use it in tools
@@ -225,7 +251,15 @@ run_diff_cmd () {
 
 # Run a either a configured or built-in merge tool
 run_merge_cmd () {
-       merge_cmd "$1"
+       mergetool_trust_exit_code=$(trust_exit_code "$1")
+       if test "$mergetool_trust_exit_code" = "true"
+       then
+               merge_cmd "$1"
+       else
+               touch "$BACKUP"
+               merge_cmd "$1"
+               check_unchanged
+       fi
 }
 
 list_merge_tool_candidates () {
@@ -316,17 +350,23 @@ guess_merge_tool () {
 }
 
 get_configured_merge_tool () {
-       # Diff mode first tries diff.tool and falls back to merge.tool.
-       # Merge mode only checks merge.tool
+       # If first argument is true, find the guitool instead
+       if test "$1" = true
+       then
+               gui_prefix=gui
+       fi
+
+       # Diff mode first tries diff.(gui)tool and falls back to merge.(gui)tool.
+       # Merge mode only checks merge.(gui)tool
        if diff_mode
        then
-               merge_tool=$(git config diff.tool || git config merge.tool)
+               merge_tool=$(git config diff.${gui_prefix}tool || git config merge.${gui_prefix}tool)
        else
-               merge_tool=$(git config merge.tool)
+               merge_tool=$(git config merge.${gui_prefix}tool)
        fi
        if test -n "$merge_tool" && ! valid_tool "$merge_tool"
        then
-               echo >&2 "git config option $TOOL_MODE.tool set to unknown tool: $merge_tool"
+               echo >&2 "git config option $TOOL_MODE.${gui_prefix}tool set to unknown tool: $merge_tool"
                echo >&2 "Resetting to default..."
                return 1
        fi
@@ -372,3 +412,28 @@ get_merge_tool () {
        fi
        echo "$merge_tool"
 }
+
+mergetool_find_win32_cmd () {
+       executable=$1
+       sub_directory=$2
+
+       # Use $executable if it exists in $PATH
+       if type -p "$executable" >/dev/null 2>&1
+       then
+               printf '%s' "$executable"
+               return
+       fi
+
+       # Look for executable in the typical locations
+       for directory in $(env | grep -Ei '^PROGRAM(FILES(\(X86\))?|W6432)=' |
+               cut -d '=' -f 2- | sort -u)
+       do
+               if test -n "$directory" && test -x "$directory/$sub_directory/$executable"
+               then
+                       printf '%s' "$directory/$sub_directory/$executable"
+                       return
+               fi
+       done
+
+       printf '%s' "$executable"
+}