Merge branch 'da/difftool-mergtool-refactor'

* da/difftool-mergtool-refactor:
  mergetools/meld: Use '--output' when available
  mergetool--lib: Refactor tools into separate files
  mergetool--lib: Make style consistent with git
  difftool--helper: Make style consistent with git

Makefile

@@ -302,6 +302,7 @@ bindir = $(prefix)/$(bindir_relative)
 mandir = share/man
 infodir = share/info
 gitexecdir = libexec/git-core
+mergetoolsdir = $(gitexecdir)/mergetools
 sharedir = $(prefix)/share
 gitwebdir = $(sharedir)/gitweb
 template_dir = share/git-core/templates
@@ -2258,6 +2259,13 @@ endif
 gitexec_instdir_SQ = $(subst ','\'',$(gitexec_instdir))
 export gitexec_instdir
 
+ifneq ($(filter /%,$(firstword $(mergetoolsdir))),)
+mergetools_instdir = $(mergetoolsdir)
+else
+mergetools_instdir = $(prefix)/$(mergetoolsdir)
+endif
+mergetools_instdir_SQ = $(subst ','\'',$(mergetools_instdir))
+
 install_bindir_programs := $(patsubst %,%$X,$(BINDIR_PROGRAMS_NEED_X)) $(BINDIR_PROGRAMS_NO_X)
 
 install: all
@@ -2267,6 +2275,9 @@ install: all
 	$(INSTALL) -m 644 $(SCRIPT_LIB) '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
 	$(INSTALL) $(install_bindir_programs) '$(DESTDIR_SQ)$(bindir_SQ)'
 	$(MAKE) -C templates DESTDIR='$(DESTDIR_SQ)' install
+	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(mergetools_instdir_SQ)'
+	(cd mergetools && $(TAR) cf - .) | \
+	(cd '$(DESTDIR_SQ)$(mergetools_instdir_SQ)' && umask 022 && $(TAR) xof -)
 ifndef NO_PERL
 	$(MAKE) -C perl prefix='$(prefix_SQ)' DESTDIR='$(DESTDIR_SQ)' install
 	$(MAKE) -C gitweb install

git-difftool--helper.sh

@@ -13,7 +13,8 @@ TOOL_MODE=diff
 should_prompt () {
 	prompt_merge=$(git config --bool mergetool.prompt || echo true)
 	prompt=$(git config --bool difftool.prompt || echo $prompt_merge)
-	if test "$prompt" = true; then
+	if test "$prompt" = true
+	then
 		test -z "$GIT_DIFFTOOL_NO_PROMPT"
 	else
 		test -n "$GIT_DIFFTOOL_PROMPT"
@@ -37,9 +38,11 @@ launch_merge_tool () {
 
 	# $LOCAL and $REMOTE are temporary files so prompt
 	# the user with the real $MERGED name before launching $merge_tool.
-	if should_prompt; then
+	if should_prompt
+	then
 		printf "\nViewing: '$MERGED'\n"
-		if use_ext_cmd; then
+		if use_ext_cmd
+		then
 			printf "Hit return to launch '%s': " \
 				"$GIT_DIFFTOOL_EXTCMD"
 		else
@@ -48,16 +51,19 @@ launch_merge_tool () {
 		read ans
 	fi
 
-	if use_ext_cmd; then
+	if use_ext_cmd
+	then
 		export BASE
 		eval $GIT_DIFFTOOL_EXTCMD '"$LOCAL"' '"$REMOTE"'
 	else
 		run_merge_tool "$merge_tool"
 	fi
 }
 
-if ! use_ext_cmd; then
-	if test -n "$GIT_DIFF_TOOL"; then
+if ! use_ext_cmd
+then
+	if test -n "$GIT_DIFF_TOOL"
+	then
 		merge_tool="$GIT_DIFF_TOOL"
 	else
 		merge_tool="$(get_merge_tool)" || exit