diff --git a/src/FileDiffWidget.cpp b/src/FileDiffWidget.cpp
index ae5c9265..5c160370 100644
--- a/src/FileDiffWidget.cpp
+++ b/src/FileDiffWidget.cpp
@@ -134,10 +134,9 @@ GitPtr FileDiffWidget::git()
 	return mainwindow()->git();
 }
 
-Git::Object FileDiffWidget::cat_file(GitPtr g, QString const &id)
+Git::Object FileDiffWidget::catFile(QString const &id)
 {
-    (void)g;
-	return mainwindow()->cat_file(mainwindow()->frame(), id);
+	return mainwindow()->catFile(id);
 }
 
 int FileDiffWidget::totalTextLines() const
@@ -599,11 +598,11 @@ void FileDiffWidget::setSideBySide_(Git::Diff const &diff, QByteArray const &ba_
 	}
 }
 
-QString FileDiffWidget::diffObjects(GitPtr g, QString const &a_id, QString const &b_id)
+QString FileDiffWidget::diffObjects(QString const &a_id, QString const &b_id)
 {
 	if (m->text_codec) {
-		Git::Object obj_a = mainwindow()->cat_file_(mainwindow()->frame(), g, a_id);
-		Git::Object obj_b = mainwindow()->cat_file_(mainwindow()->frame(), g, b_id);
+		Git::Object obj_a = mainwindow()->catFile(a_id);
+		Git::Object obj_b = mainwindow()->catFile(b_id);
 		if (obj_b.type == Git::Object::Type::UNKNOWN) {
 			obj_b.type = Git::Object::Type::BLOB;
 		}
@@ -617,14 +616,14 @@ QString FileDiffWidget::diffObjects(GitPtr g, QString const &a_id, QString const
 				file_b.write(m->text_codec->toUnicode(obj_b.content).toUtf8());
 				file_a.close();
 				file_b.close();
-				QString s = g->diff_file(path_a, path_b);
+				QString s = git()->diff_file(path_a, path_b);
 				file_a.remove();
 				file_b.remove();
 				return s;
 			}
 		}
 	}
-	return GitDiff::diffObjects(g, a_id, b_id);
+	return GitDiff::diffObjects(git(), a_id, b_id);
 }
 
 /**
@@ -652,8 +651,8 @@ void FileDiffWidget::updateDiffView(Git::Diff const &info, bool uncommited)
 	if (!g->isValidWorkingCopy()) return;
 
 	if (isValidID_(info.blob.a_id_or_path) && isValidID_(info.blob.b_id_or_path)) {
-		Git::Object obj_a = cat_file(g, info.blob.a_id_or_path);
-		Git::Object obj_b = cat_file(g, info.blob.b_id_or_path);
+		Git::Object obj_a = catFile(info.blob.a_id_or_path);
+		Git::Object obj_b = catFile(info.blob.b_id_or_path);
 		QString mime_a = mainwindow()->determinFileType(obj_a.content);
 		QString mime_b = mainwindow()->determinFileType(obj_b.content);
 		if (misc::isImage(mime_a) && misc::isImage(mime_b)) {
@@ -665,7 +664,7 @@ void FileDiffWidget::updateDiffView(Git::Diff const &info, bool uncommited)
 	{
 		Git::Diff diff;
 		if (isValidID_(info.blob.a_id_or_path) && isValidID_(info.blob.b_id_or_path)) {
-			std::string text = diffObjects(g, info.blob.a_id_or_path, info.blob.b_id_or_path).toStdString();
+			std::string text = diffObjects(info.blob.a_id_or_path, info.blob.b_id_or_path).toStdString();
 			GitDiff::parseDiff(text, &info, &diff);
 		} else {
 			diff = info;
@@ -673,14 +672,14 @@ void FileDiffWidget::updateDiffView(Git::Diff const &info, bool uncommited)
 
 		Git::Object obj;
 		if (isValidID_(diff.blob.a_id_or_path)) { // 左が有効
-			obj = cat_file(g, diff.blob.a_id_or_path);
+			obj = catFile(diff.blob.a_id_or_path);
 			if (isValidID_(diff.blob.b_id_or_path)) { // 右が有効
 				setSideBySide(diff, obj.content, uncommited, g->workingDir()); // 通常のdiff表示
 			} else {
 				setLeftOnly(diff, obj.content); // 右が無効の時は、削除されたファイル
 			}
 		} else if (isValidID_(diff.blob.b_id_or_path)) { // 左が無効で右が有効の時は、追加されたファイル
-			obj = cat_file(g, diff.blob.b_id_or_path);
+			obj = catFile(diff.blob.b_id_or_path);
 			setRightOnly(diff, obj.content);
 		}
 	}
@@ -703,10 +702,10 @@ void FileDiffWidget::updateDiffView(QString const &id_left, QString const &id_ri
 	diff.blob.a_id_or_path = id_left;
 	diff.blob.b_id_or_path = id_right;
 	diff.mode = "0";
-	std::string text = diffObjects(g, diff.blob.a_id_or_path, diff.blob.b_id_or_path).toStdString();
+	std::string text = diffObjects(diff.blob.a_id_or_path, diff.blob.b_id_or_path).toStdString();
 	GitDiff::parseDiff(text, &diff, &diff);
 
-	Git::Object obj = cat_file(g, diff.blob.a_id_or_path);
+	Git::Object obj = catFile(diff.blob.a_id_or_path);
 	setSideBySide(diff, obj.content, false, g->workingDir());
 
 	ui->widget_diff_slider->clear(false);
diff --git a/src/FileDiffWidget.h b/src/FileDiffWidget.h
index bc999909..ffe81f8d 100644
--- a/src/FileDiffWidget.h
+++ b/src/FileDiffWidget.h
@@ -97,7 +97,7 @@ class FileDiffWidget : public QWidget {
 	ViewStyle viewstyle() const;
 
 	GitPtr git();
-	Git::Object cat_file(GitPtr g, QString const &id);
+	Git::Object catFile(QString const &id);
 
 	int totalTextLines() const;
 
@@ -124,7 +124,7 @@ class FileDiffWidget : public QWidget {
 	void refrectScrollBarV();
 	void refrectScrollBarH();
 	void setOriginalLines_(QByteArray const &ba, const Git::SubmoduleItem *submodule, const Git::CommitItem *submodule_commit);
-	QString diffObjects(GitPtr g, QString const &a_id, QString const &b_id);
+	QString diffObjects(QString const &a_id, QString const &b_id);
 	MainWindow *mainwindow();
 	bool setSubmodule(const Git::Diff &diff);
 protected:
diff --git a/src/Git.cpp b/src/Git.cpp
index 01e1045c..cf48b9a6 100644
--- a/src/Git.cpp
+++ b/src/Git.cpp
@@ -448,10 +448,10 @@ QList<Git::Tag> Git::tags2()
 	return list;
 }
 
-bool Git::tag(QString const &name, QString const &id)
+bool Git::tag(QString const &name, CommitID const &id)
 {
 	QString cmd = "tag \"%1\" %2";
-	cmd = cmd.arg(name).arg(id);
+	cmd = cmd.arg(name).arg(id.toQString());
 	return git(cmd);
 }
 
@@ -798,12 +798,12 @@ std::optional<Git::CommitItem> Git::parseCommitItem(QString const &line)
  * @param maxcount 最大アイテム数
  * @return
  */
-Git::CommitItemList Git::log_all(QString const &id, int maxcount)
+Git::CommitItemList Git::log_all(CommitID const &id, int maxcount)
 {
 	CommitItemList items;
 
 	QString cmd = "log --pretty=format:\"id:%H#parent:%P#author:%an#mail:%ae#date:%ci##%s\" --all -%1 %2";
-	cmd = cmd.arg(maxcount).arg(id);
+	cmd = cmd.arg(maxcount).arg(id.toQString());
 	git(cmd);
 	if (getProcessExitCode() == 0) {
 		QString text = resultQString().trimmed();
@@ -1117,10 +1117,10 @@ bool Git::commit_amend_m(QString const &text, bool sign, AbstractPtyProcess *pty
 	return commit_(text, true, sign, pty);
 }
 
-bool Git::revert(QString const &id)
+bool Git::revert(CommitID const &id)
 {
 	QString cmd = "revert %1";
-	cmd = cmd.arg(id);
+	cmd = cmd.arg(id.toQString());
 	return git(cmd);
 }
 
diff --git a/src/Git.h b/src/Git.h
index ff169df4..ba18699d 100644
--- a/src/Git.h
+++ b/src/Git.h
@@ -77,7 +77,7 @@ class Git : QObject {
 			OFS_DELTA = 6,
 			REF_DELTA = 7,
 		};
-		Type type = Type::UNKNOWN;
+		Type type = Type::NONE;
 		QByteArray content;
 	};
 
@@ -382,7 +382,7 @@ class Git : QObject {
 	QString version();
 	bool init();
 	QStringList getUntrackedFiles();
-	CommitItemList log_all(QString const &id, int maxcount);
+	CommitItemList log_all(CommitID const &id, int maxcount);
 	std::optional<CommitItem> log_signature(CommitID const &id);
 	CommitItemList log(int maxcount);
 	std::optional<CommitItem> queryCommit(const CommitID &id);
@@ -448,7 +448,7 @@ class Git : QObject {
 	QString status();
 	bool commit(QString const &text, bool sign, AbstractPtyProcess *pty);
 	bool commit_amend_m(QString const &text, bool sign, AbstractPtyProcess *pty);
-	bool revert(QString const &id);
+	bool revert(const CommitID &id);
 	bool push_tags(AbstractPtyProcess *pty = nullptr);
 	void getRemoteURLs(QList<Remote> *out);
 	void createBranch(QString const &name);
@@ -463,7 +463,7 @@ class Git : QObject {
 	CommitID rev_parse(QString const &name);
 	QList<Tag> tags();
 	QList<Tag> tags2();
-	bool tag(QString const &name, QString const &id = QString());
+	bool tag(QString const &name, const CommitID &id = QString());
 	void delete_tag(QString const &name, bool remote);
 	void setRemoteURL(const Remote &remote);
 	void addRemoteURL(const Remote &remote);
diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 4c6a43cd..0d7a1ae6 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -146,8 +146,6 @@ struct MainWindow::Private {
 	QString repository_filter_text;
 	bool uncommited_changes = false;
 
-//	bool remote_changed = false;
-
 	GitHubRepositoryInfo github;
 
 	Git::CommitID head_id;
@@ -625,20 +623,15 @@ bool MainWindow::eventFilter(QObject *watched, QEvent *event)
 		if (watched == frame()->unstagedFileslistwidget()) {
 			m->last_focused_file_list = watched;
 			updateStatusBarText(frame());
-//			updateUnstagedFileCurrentItem(frame());
-//			SelectItem(frame()->unstagedFileslistwidget());
 			return true;
 		}
 		if (watched == frame()->stagedFileslistwidget()) {
 			m->last_focused_file_list = watched;
 			updateStatusBarText(frame());
-//			updateStagedFileCurrentItem(frame());
-//			SelectItem(frame()->stagedFileslistwidget());
 			return true;
 		}
 		if (watched == frame()->fileslistwidget()) {
 			m->last_focused_file_list = watched;
-//			SelectItem(frame()->fileslistwidget());
 			return true;
 		}
 	}
@@ -759,9 +752,7 @@ std::vector<std::string> MainWindow::getLogHistoryLines()
 
 void MainWindow::clearLogHistory()
 {
-//	if (m->log_history_bytes.empty()) return;
 	m->log_history_bytes.clear();
-//	qDebug() << "---";
 }
 
 void MainWindow::internalWriteLog(char const *ptr, int len, bool record)
@@ -846,11 +837,6 @@ QString MainWindow::defaultWorkingDir() const
 	return appsettings()->default_working_dir;
 }
 
-//WebContext *MainWindow::webContext()
-//{
-//	return &m->webcx;
-//}
-
 QIcon MainWindow::verifiedIcon(char s) const
 {
 	Git::SignatureGrade g = Git::evaluateSignature(s);
@@ -1003,7 +989,7 @@ bool MainWindow::addExistingLocalRepository(QString dir, QString name, QString s
 	if (open) {
 		setCurrentRepository(item, true);
 		GitPtr g = git(item.local_dir, {}, sshkey);
-		openRepository_(g);
+		internalOpenRepository(g);
 	}
 
 	return true;
@@ -1132,7 +1118,7 @@ bool MainWindow::checkGitCommand()
 
 bool MainWindow::saveBlobAs(RepositoryWrapperFrame *frame, const QString &id, const QString &dstpath)
 {
-	Git::Object obj = cat_file(frame, id);
+	Git::Object obj = internalCatFile(frame, id);
 	if (!obj.content.isEmpty()) {
 		if (saveByteArrayAs(obj.content, dstpath)) {
 			return true;
@@ -1219,14 +1205,12 @@ bool MainWindow::checkExecutable(const QString &path)
 
 void MainWindow::internalSaveCommandPath(const QString &path, bool save, const QString &name)
 {
-//	if (checkExecutable(path)) {
-		if (save) {
-			MySettings s;
-			s.beginGroup("Global");
-			s.setValue(name, path);
-			s.endGroup();
-		}
-//	}
+	if (save) {
+		MySettings s;
+		s.beginGroup("Global");
+		s.setValue(name, path);
+		s.endGroup();
+	}
 }
 
 void MainWindow::logGitVersion()
@@ -1288,7 +1272,7 @@ void MainWindow::openRepository(bool validate, bool waitcursor, bool keep_select
 		qDebug() << "Guitar: git pointer is null";
 		return;
 	}
-	openRepository_(g, keep_selection);
+	internalOpenRepository(g, keep_selection);
 }
 
 void MainWindow::updateRepository()
@@ -1297,7 +1281,7 @@ void MainWindow::updateRepository()
 	if (!isValidWorkingCopy(g)) return;
 
 	OverrideWaitCursor;
-	openRepository_(g);
+	internalOpenRepository(g);
 }
 
 void MainWindow::reopenRepository(bool log, const std::function<void (GitPtr )> &callback)
@@ -1318,7 +1302,7 @@ void MainWindow::reopenRepository(bool log, const std::function<void (GitPtr )>
 	} else {
 		callback(g);
 	}
-	openRepository_(g);
+	internalOpenRepository(g);
 }
 
 void MainWindow::setCurrentRepository(const RepositoryData &repo, bool clear_authentication)
@@ -1544,7 +1528,7 @@ void MainWindow::submodule_add(QString url, QString const &local_dir)
 				}
 				setLogEnabled(g, false);
 			}
-			openRepository_(g);
+			internalOpenRepository(g);
 		}
 
 		return; // done
@@ -3626,28 +3610,7 @@ void MainWindow::clearLog(RepositoryWrapperFrame *frame)
 	frame->clearLogContents();
 }
 
-void MainWindow::openRepository_(GitPtr g, bool keep_selection)
-{
-	openRepository_(frame(), g, keep_selection);
-}
-
-MainWindow::GitFile MainWindow::catFile(Git::CommitID const &id, GitPtr g)
-{
-	GitFile file;
-	if (0) { //@TODO:いつか消す
-		auto ba = g->cat_file(id);
-		if (ba) {
-			file.data = *ba;
-		}
-	} else {
-		Git::Object::Type type;
-		GitObjectManager om(g);
-		om.catFile(id, &file.data, &file.type);
-	}
-	return file;
-}
-
-Git::Object MainWindow::cat_file_(RepositoryWrapperFrame *frame, GitPtr g, const QString &id) //@TODO:
+Git::Object MainWindow::internalCatFile(RepositoryWrapperFrame *frame, GitPtr g, const QString &id) //@TODO:
 {
 	if (isValidWorkingCopy(g)) {
 		QString path_prefix = PATH_PREFIX;
@@ -3664,15 +3627,25 @@ Git::Object MainWindow::cat_file_(RepositoryWrapperFrame *frame, GitPtr g, const
 			return getObjCache(frame)->catFile(id);;
 		}
 	}
-	return Git::Object();
+	return {};
+}
+
+Git::Object MainWindow::internalCatFile(RepositoryWrapperFrame *frame, const QString &id) //@TODO:
+{
+	return internalCatFile(frame, git(), id);
 }
 
-Git::Object MainWindow::cat_file(RepositoryWrapperFrame *frame, const QString &id) //@TODO:
+Git::Object MainWindow::catFile(QString const &id)
 {
-	return cat_file_(frame, git(), id);
+	return internalCatFile(frame(), git(), id);
 }
 
-void MainWindow::openRepository_(RepositoryWrapperFrame *frame, GitPtr g, bool keep_selection)
+void MainWindow::internalOpenRepository(GitPtr g, bool keep_selection)
+{
+	openRepositoryWithFrame(frame(), g, keep_selection);
+}
+
+void MainWindow::openRepositoryWithFrame(RepositoryWrapperFrame *frame, GitPtr g, bool keep_selection)
 {
 	getObjCache(frame)->setup(g);
 
@@ -4660,24 +4633,11 @@ void MainWindow::showObjectProperty(QListWidgetItem *item)
 	if (item) {
 		QString submodpath = getSubmodulePath(item);
 		if (!submodpath.isEmpty()) {
-#if 0
-			// サブモジュールウィンドウを表示する
-			Git::SubmoduleItem submod;
-			submod.path = submodpath;
-			submod.id = getObjectID(item);
-			if (submod) {
-				OverrideWaitCursor;
-				GitPtr g = git(submod);
-				SubmoduleMainWindow *w = new SubmoduleMainWindow(this, g);
-				w->show();
-				w->reset();
-			}
-#else
+			// サブモジュールのときは新しいプロセスを起動する
 			QString commit_id = getSubmoduleCommitId(item);
 			QString path = currentWorkingCopyDir() / submodpath;
 			qDebug() << path << commit_id;
 			QProcess::execute(global->this_executive_program, {path, "--commit-id", commit_id});
-#endif
 		} else {
 			// ファイルプロパティダイアログを表示する
 			QString path = getFilePath(item);
diff --git a/src/MainWindow.h b/src/MainWindow.h
index 9ec45230..6f9a8860 100644
--- a/src/MainWindow.h
+++ b/src/MainWindow.h
@@ -160,8 +160,8 @@ class MainWindow : public QMainWindow {
 	void updateFilesList(RepositoryWrapperFrame *frame, Git::CommitItem const &commit, bool wait);
 	void updateRepositoriesList();
 
-	void openRepository_(GitPtr g, bool keep_selection = false);
-	void openRepository_(RepositoryWrapperFrame *frame, GitPtr g, bool keep_selection = false);
+	void internalOpenRepository(GitPtr g, bool keep_selection = false);
+	void openRepositoryWithFrame(RepositoryWrapperFrame *frame, GitPtr g, bool keep_selection = false);
 
 	QStringList selectedFiles_(QListWidget *listwidget) const;
 	QStringList selectedFiles() const;
@@ -282,7 +282,7 @@ class MainWindow : public QMainWindow {
         Git::CommitID idFromTag(RepositoryWrapperFrame *frame, const QString &tag);
 	QString newTempFilePath();
 	int limitLogCount() const;
-    Git::Object cat_file_(RepositoryWrapperFrame *frame, GitPtr g, const QString &id);
+	Git::Object internalCatFile(RepositoryWrapperFrame *frame, GitPtr g, const QString &id);
 	bool isThereUncommitedChanges() const;
 	static void addDiffItems(const QList<Git::Diff> *diff_list, const std::function<void (const ObjectData &)> &add_item);
     Git::CommitItemList retrieveCommitLog(GitPtr g);
@@ -392,7 +392,7 @@ class MainWindow : public QMainWindow {
 	class GitFile {
 	public:
 		Git::Object::Type type = Git::Object::Type::NONE;
-		QByteArray data;
+		QByteArray content;
 		operator bool () const
 		{
 			return type != Git::Object::Type::NONE;
@@ -452,13 +452,13 @@ class MainWindow : public QMainWindow {
 	GitPtr git(const QString &dir, const QString &submodpath, const QString &sshkey) const;
 	GitPtr git();
 	GitPtr git(Git::SubmoduleItem const &submod);
-	GitFile catFile(const Git::CommitID &id, GitPtr g);
 	void autoOpenRepository(QString dir, const QString &commit_id = {});
 	std::optional<Git::CommitItem> queryCommit(const QString &id);
 	void checkout(RepositoryWrapperFrame *frame, QWidget *parent, const Git::CommitItem *commit, std::function<void ()> accepted_callback = {});
 	void checkout(RepositoryWrapperFrame *frame);
 	void jumpToCommit(RepositoryWrapperFrame *frame, QString id);
-	Git::Object cat_file(RepositoryWrapperFrame *frame, const QString &id);
+	Git::Object internalCatFile(RepositoryWrapperFrame *frame, const QString &id);
+	Git::Object catFile(const QString &id);
 	bool addExistingLocalRepository(const QString &dir, bool open);
 	bool saveAs(RepositoryWrapperFrame *frame, const QString &id, const QString &dstpath);
 	QString determinFileType(QByteArray in);
diff --git a/src/SubmoduleMainWindow.cpp b/src/SubmoduleMainWindow.cpp
index af785a50..d1757fb7 100644
--- a/src/SubmoduleMainWindow.cpp
+++ b/src/SubmoduleMainWindow.cpp
@@ -47,6 +47,6 @@ RepositoryWrapperFrame *SubmoduleMainWindow::frame()
 void SubmoduleMainWindow::reset()
 {
 	GitPtr g = git();
-	mainwindow()->openRepository_(ui->frame_repository_wrapper2, g);
+	mainwindow()->openRepositoryWithFrame(ui->frame_repository_wrapper2, g);
 
 }