Fix the saved date and time lagging one save in the title block

The title block variables of a save (saveddate, saveddate-eu,
saveddate-us, savedtime, savedfilename, savedfilepath) were set after
the file was written, and also when a project was opened. A file
therefore held the previous save's date and path: after editing and
saving, the title block showed the date of the save before. And every
save but the first in a session wrote the time of the one before, so a
project saved twice without a change gave two different files, a diff
for nothing in a project kept in git (discussion #1512).

stampSaved() now sets them before writing, when the project has
unsaved changes (the modified flag or the undo stack moved since the
last save, as the window's "[modified]" uses) or is written to another
file. Otherwise they keep what the file holds, and opening a project no
longer sets them.

tst_savedstamps: an unchanged project saved twice in place is
byte-identical; a moved symbol then a save gives today's date and the
file's own path. Both fail without the fix.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XCdg2Er2vYhB8Vwa5G7fSR

sources/qetproject.cpp

@@ -474,6 +474,8 @@ QETProject::ProjectState QETProject::openFile(QFile *file)
 	}
 	QFileInfo fi(*file);
 	setFilePath(fi.absoluteFilePath());
+		//Saved again unchanged, the file keeps its saved date and path
+	m_stamped_path = m_file_path;
 
 		//Extract the content of the xml. The raw bytes are kept : a project
 		//file without a persisted uuid derives its uuid from them.
@@ -1161,16 +1163,8 @@ void QETProject::setFilePath(const QString &filepath)
 		setReadOnly(false);
 	}
 
-		//title block variables should be updated after file save as dialog is confirmed, before file is saved.
-	m_project_properties.addValue("saveddate",     QLocale::system().toString(QDate::currentDate(), QLocale::ShortFormat));
-	m_project_properties.addValue("saveddate-eu",  QDate::currentDate().toString("dd-MM-yyyy"));
-	m_project_properties.addValue("saveddate-us",  QDate::currentDate().toString("yyyy-MM-dd"));
-	m_project_properties.addValue("savedtime",     QDateTime::currentDateTime().toString("HH:mm"));
-	m_project_properties.addValue("savedfilename", QFileInfo(filePath()).completeBaseName());
-	m_project_properties.addValue("savedfilepath", filePath());
-
-
-
+		//The saved date, time and path of the title block are set by
+		//write(), when the project is saved (stampSaved())
 	emit projectFilePathChanged(this, m_file_path);
 	emit projectInformationsChanged(this);
 	updateDiagramsFolioData();
@@ -2801,6 +2795,33 @@ bool QETProject::changedOnDisk(QDateTime *when) const
 	return true;
 }
 
+/**
+	@brief QETProject::stampSaved
+	Set the title block variables of the save (saveddate, saveddate-eu,
+	saveddate-us, savedtime, savedfilename, savedfilepath) to now and to
+	the file being written, when there is something new to save: the
+	project changed since it was opened or last saved, or it is written to
+	another file. Otherwise they keep what the file holds, so saving an
+	unchanged project gives an identical file (F124).
+	@return true if they were set
+*/
+bool QETProject::stampSaved()
+{
+	const bool changed = m_modified || m_undo_stack->index() != m_stamped_undo_index;
+	if (!changed && m_file_path == m_stamped_path) {
+		return false;
+	}
+	m_project_properties.addValue("saveddate",     QLocale::system().toString(QDate::currentDate(), QLocale::ShortFormat));
+	m_project_properties.addValue("saveddate-eu",  QDate::currentDate().toString("dd-MM-yyyy"));
+	m_project_properties.addValue("saveddate-us",  QDate::currentDate().toString("yyyy-MM-dd"));
+	m_project_properties.addValue("savedtime",     QDateTime::currentDateTime().toString("HH:mm"));
+	m_project_properties.addValue("savedfilename", QFileInfo(filePath()).completeBaseName());
+	m_project_properties.addValue("savedfilepath", filePath());
+	emit projectInformationsChanged(this);
+	updateDiagramsFolioData();
+	return true;
+}
+
 /**
 	@brief QETProject::write
 	Save the project in a file.
@@ -2868,13 +2889,28 @@ QETResult QETProject::write(bool overwrite_changed)
 	if (!PreviousVersions::keep(m_file_path, PreviousVersions::count(), &backup_error))
 		qWarning().noquote() << "Previous version of" << m_file_path << "not kept:" << backup_error;
 
+		//The saved date, time and path go into the file being written, and
+		//only when there is something new to save: an unchanged project
+		//saves to an identical file (F124, a project kept in git). A
+		//failed write puts the previous values back.
+	const DiagramContext stamped_before = m_project_properties;
+	const bool stamped = stampSaved();
+	const auto failed_stamped = [&](const QString &error) {
+		if (stamped) {
+			m_project_properties = stamped_before;
+			emit projectInformationsChanged(this);
+			updateDiagramsFolioData();
+		}
+		return failed(error);
+	};
+
 	QString error_message;
 	if (isContainerPath(m_file_path))
 	{
 			//A container is written from the whole document: every folio
 			//built (stage D4 writes it from the database)
 		if (!writeContainerFile(m_file_path, &error_message))
-			return(failed(error_message));
+			return(failed_stamped(error_message));
 	}
 	else
 	{
@@ -2884,7 +2920,7 @@ QETResult QETProject::write(bool overwrite_changed)
 		QDomDocument xml_project(toXml(&kept_folios));
 		if (!QET::writeXmlText(spliceKeptFolios(xml_project.toString(4), kept_folios),
 						   m_file_path, &error_message))
-			return(failed(error_message));
+			return(failed_stamped(error_message));
 	}
 
 	rememberDiskState();
@@ -2905,17 +2941,8 @@ QETResult QETProject::write(bool overwrite_changed)
 		}
 	}
 
-		//title block variables should be updated after file save dialog is confirmed, before file is saved.
-	m_project_properties.addValue("saveddate",     QLocale::system().toString(QDate::currentDate(), QLocale::ShortFormat));
-	m_project_properties.addValue("saveddate-us",  QDate::currentDate().toString("yyyy-MM-dd"));
-	m_project_properties.addValue("saveddate-eu",  QDate::currentDate().toString("dd-MM-yyyy"));
-	m_project_properties.addValue("savedtime",     QDateTime::currentDateTime().toString("HH:mm"));
-	m_project_properties.addValue("savedfilename", QFileInfo(filePath()).completeBaseName());
-	m_project_properties.addValue("savedfilepath", filePath());
-
-	emit projectInformationsChanged(this);
-	updateDiagramsFolioData();
-
+	m_stamped_path = m_file_path;
+	m_stamped_undo_index = m_undo_stack->index();
 	setModified(false);
 	return(QETResult());
 }

sources/qetproject.h

@@ -441,6 +441,7 @@ class QETProject : public QObject
 		}
 
 	private:
+		bool stampSaved();
 		void readProjectXml(QDomDocument &xml_project);
 		void readDiagramsXml(QDomDocument &xml_project);
 		void readElementsCollectionXml(QDomDocument &xml_project);
@@ -570,6 +571,10 @@ class QETProject : public QObject
 		bool m_kept_folios_trusted = false;
 			/// Read from a .qet whose path nobody chose since: saved beside it
 		bool m_opened_from_qet = false;
+			/// The file the saved date and path were set for, and the undo
+			/// index then: an unchanged project keeps them (stampSaved())
+		QString m_stamped_path;
+		int m_stamped_undo_index = 0;
 			/// The project file as this QET last read or wrote it, to see
 			/// whether something else changed it since (changedOnDisk())
 		QString m_disk_path;

tests/qttest/CMakeLists.txt

@@ -889,6 +889,18 @@ if(QET_HAS_SCRIPTING)
   target_compile_definitions(tst_scriptconductoruuid PRIVATE
     "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\"")
 
+  # The saved date, time and path of the title block change only when the
+  # project changed, and go into the file that save writes (F124): an
+  # unchanged project saved twice gives an identical file.
+  add_executable(
+    tst_savedstamps
+    tst_savedstamps.cpp)
+  add_test(NAME tst_savedstamps COMMAND tst_savedstamps)
+  add_dependencies(tst_savedstamps qelectrotech)
+  target_link_libraries(tst_savedstamps PRIVATE Qt::Test Qt::Xml)
+  target_compile_definitions(tst_savedstamps PRIVATE
+    "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\"")
+
   # qet.terminalPosition() and qet.conductorPath(), checked against each
   # other on a fixture's conductors.
   add_executable(

tests/qttest/tst_savedstamps.cpp

@@ -0,0 +1,143 @@
+/*
+	Copyright 2006-2026 The QElectroTech Team
+	This file is part of QElectroTech.
+
+	QElectroTech is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 2 of the License, or
+	(at your option) any later version.
+
+	QElectroTech is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with QElectroTech.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include <QtTest>
+#include <QDate>
+#include <QDomDocument>
+#include <QProcess>
+#include <QTemporaryDir>
+
+/**
+	The title block variables of a save (saveddate, savedtime,
+	savedfilename, savedfilepath...) are set when the project is saved
+	with something new in it, and go into the file that save writes. They
+	used to be set after writing, so each save wrote the time of the one
+	before: a project saved twice without a change gave two different
+	files, and a changed project was saved with the previous date.
+
+	Runs the real binary on fixtures/unlinked_contact_label.qet, whose
+	stamps say 2026-10-02 18:39 in a temporary folder:
+	- saved twice in its own file without a change: byte-identical;
+	- one symbol moved, then saved: today's date and the file's own path.
+*/
+class tst_savedstamps : public QObject
+{
+	Q_OBJECT
+
+	QTemporaryDir m_dir;
+	QString m_base;
+
+	QString run(const QStringList &arguments)
+	{
+		QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+		env.insert(QStringLiteral("QT_QPA_PLATFORM"), QStringLiteral("offscreen"));
+			//Its own settings and single-instance socket: another test's
+			//QElectroTech running at the same time would otherwise be
+			//handed this run (SingleApplication)
+		const QString home = m_dir.filePath(QStringLiteral("home"));
+		QDir().mkpath(home);
+		env.insert(QStringLiteral("HOME"), home);
+		env.insert(QStringLiteral("XDG_CONFIG_HOME"), home + QStringLiteral("/config"));
+		env.insert(QStringLiteral("XDG_DATA_HOME"), home + QStringLiteral("/data"));
+		env.insert(QStringLiteral("TMPDIR"), m_dir.path());
+		env.insert(QStringLiteral("QET_ENABLE_SCRIPTING"), QStringLiteral("1"));
+		QProcess proc;
+		proc.setProcessEnvironment(env);
+		proc.setProcessChannelMode(QProcess::MergedChannels);
+		proc.start(QStringLiteral(QET_TEST_BINARY_PATH), arguments);
+		if (!proc.waitForFinished(120000) || proc.exitStatus() != QProcess::NormalExit
+				|| proc.exitCode() != 0)
+			return QString();
+		return QString::fromUtf8(proc.readAll()) + QStringLiteral("\nEXIT 0");
+	}
+
+	QString script(const QString &name, const QString &body)
+	{
+		const QString path = m_dir.filePath(name);
+		QFile file(path);
+		if (!file.open(QIODevice::WriteOnly)) return QString();
+		file.write(body.toUtf8());
+		return path;
+	}
+
+		/// The saved-* properties of @p qetz, read back through --resave
+	QMap<QString, QString> stamps(const QString &qetz)
+	{
+		const QString xml = qetz + QStringLiteral(".qet");
+		if (run({QStringLiteral("--resave"), qetz, xml}).isEmpty()) return {};
+		QFile file(xml);
+		QDomDocument doc;
+		if (!file.open(QIODevice::ReadOnly) || !doc.setContent(&file)) return {};
+		QMap<QString, QString> out;
+		const QDomNodeList props = doc.documentElement().firstChildElement(
+					QStringLiteral("properties")).elementsByTagName(QStringLiteral("property"));
+		for (int i = 0; i < props.size(); ++i) {
+			const QDomElement p = props.at(i).toElement();
+			if (p.attribute(QStringLiteral("name")).startsWith(QLatin1String("saved")))
+				out.insert(p.attribute(QStringLiteral("name")), p.text());
+		}
+		return out;
+	}
+
+	static QByteArray bytes(const QString &path)
+	{
+		QFile file(path);
+		return file.open(QIODevice::ReadOnly) ? file.readAll() : QByteArray();
+	}
+
+private slots:
+	void initTestCase()
+	{
+		QVERIFY2(QFile::exists(QStringLiteral(QET_TEST_BINARY_PATH)), "qelectrotech binary not found");
+		QVERIFY(m_dir.isValid());
+		const QString fixture = QFINDTESTDATA("fixtures/unlinked_contact_label.qet");
+		QVERIFY2(!fixture.isEmpty(), "fixture project not found");
+			//The fixture as a .qetz, its stamps as they were: a copy
+			//written by --resave is not a save of the project
+		m_base = m_dir.filePath(QStringLiteral("base.qetz"));
+		QVERIFY(!run({QStringLiteral("--resave"), fixture, m_base}).isEmpty());
+		QCOMPARE(stamps(m_base).value(QStringLiteral("saveddate-us")), QStringLiteral("2026-10-02"));
+	}
+
+	void unchangedSavesAreIdentical()
+	{
+		const QString project = m_dir.filePath(QStringLiteral("unchanged.qetz"));
+		QVERIFY(QFile::copy(m_base, project));
+		const QString js = script(QStringLiteral("unchanged.js"),
+			QStringLiteral("qet.save('');\nqet.save('');\nqet.log('SAVED twice');\n"));
+		QVERIFY(run({QStringLiteral("--run"), js, project}).contains(QLatin1String("SAVED twice")));
+		QCOMPARE(bytes(project), bytes(m_base));
+	}
+
+	void changedSaveIsStampedNow()
+	{
+		const QString project = m_dir.filePath(QStringLiteral("changed.qetz"));
+		QVERIFY(QFile::copy(m_base, project));
+		const QString js = script(QStringLiteral("changed.js"), QStringLiteral(
+			"var u = qet.elementUuids(0)[0];\n"
+			"qet.log('MOVED ' + qet.moveElement(0, u, 10, 0));\n"
+			"qet.save('');\n"));
+		QVERIFY(run({QStringLiteral("--run"), js, project}).contains(QLatin1String("MOVED true")));
+		const QMap<QString, QString> s = stamps(project);
+		QCOMPARE(s.value(QStringLiteral("saveddate-us")), QDate::currentDate().toString(QStringLiteral("yyyy-MM-dd")));
+		QCOMPARE(s.value(QStringLiteral("savedfilepath")), QFileInfo(project).absoluteFilePath());
+		QCOMPARE(s.value(QStringLiteral("savedfilename")), QStringLiteral("changed"));
+	}
+};
+
+QTEST_GUILESS_MAIN(tst_savedstamps)
+#include "tst_savedstamps.moc"