Fix folio dates a century early in the project database

diagram_info.date -- and project_summary_view.date, which the summary
table dialog queries -- held the folio date read back from the title
block's text: QLocale::system().toDate() of the string
updateDiagramContextForTitleBlock() writes in the locale's short format.
Where that format has a two-digit year (en_US "M/d/yy") Qt reads the year
back as 19xx, so 741.qet's 2010-09-21 became 1910-09-21, and so did every
dated folio of the 24 examples (109 of 109).

bindDiagramInfoValues() now binds the folio's own date,
BorderTitleBlock::date(), the value that text was made from. A folio set
to show the current date or none gives the same date as before.

tst_dbfoliodate runs --run on examples/741.qet under LC_ALL=en_US.UTF-8
and expects 2010-09-21 from project_summary_view: 1910-09-21 without this
change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

sources/dataBase/projectdatabase.cpp

@@ -1741,9 +1741,12 @@ void projectDataBase::bindDiagramInfoValues(QSqlQuery &query, Diagram *diagram)
 	for (auto key : QETInformation::diagramInfoKeys())
 	{
 		if (key == "date") {
-			query.bindValue( ":date",
-							 QLocale::system().toDate(infos.value("date").toString(),
-													  QLocale::ShortFormat));
+				//The folio's own date, not the title block's text read
+				//back: that text is the locale's short format, and where
+				//it has a two-digit year (en_US "M/d/yy") toDate() reads
+				//2010 back as 1910.
+			query.bindValue(QStringLiteral(":date"),
+							diagram->border_and_titleblock.date());
 		} else {
 			auto value = infos.value(key);
 			auto bind = key.prepend(":");

tests/qttest/CMakeLists.txt

@@ -344,6 +344,18 @@ if(QET_HAS_SCRIPTING)
   target_compile_definitions(tst_scriptconductoruuid PRIVATE
     "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\"")
 
+  # The project database keeps a folio's date with its century: 741.qet's
+  # 2010-09-21, read through project_summary_view under LC_ALL=en_US.UTF-8.
+  add_executable(
+    tst_dbfoliodate
+    tst_dbfoliodate.cpp)
+  add_test(NAME tst_dbfoliodate COMMAND tst_dbfoliodate)
+  add_dependencies(tst_dbfoliodate qelectrotech)
+  target_link_libraries(tst_dbfoliodate PRIVATE Qt::Test)
+  target_compile_definitions(tst_dbfoliodate PRIVATE
+    "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\""
+    "QET_EXAMPLES_DIR=\"${QET_DIR}/examples\"")
+
   # qet.elementTerminals() lists each terminal's uuid and qet.terminalIndex()
   # turns element uuid + terminal uuid back into the index the conductor
   # calls take, on examples/perceuse.qet (two terminals at one point).

tests/qttest/tst_dbfoliodate.cpp

@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <QtTest>
+
+#include <QFile>
+#include <QJsonArray>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QProcess>
+#include <QProcessEnvironment>
+#include <QTemporaryDir>
+
+// The project database holds each folio's own date. It used to hold the
+// title block's text read back through the locale's short format, which in a
+// locale with a two-digit year (en_US "M/d/yy") turned 2010 into 1910 -- in
+// diagram_info and in project_summary_view, which the summary table reads.
+// Runs a script through the real binary's --run on examples/741.qet, whose
+// folio is dated 20100921, with LC_ALL=en_US.UTF-8.
+class tst_dbfoliodate : public QObject
+{
+	Q_OBJECT
+
+	QTemporaryDir m_dir;
+
+private slots:
+	void initTestCase()
+	{
+		QVERIFY(m_dir.isValid());
+		QVERIFY(QFile::exists(QStringLiteral(QET_TEST_BINARY_PATH)));
+	}
+
+	void folioDateKeepsItsCentury()
+	{
+		const QString path = m_dir.filePath(QStringLiteral("probe.js"));
+		const QString home = m_dir.filePath(QStringLiteral("home"));
+		QDir().mkpath(home);
+		QFile f(path);
+		QVERIFY(f.open(QIODevice::WriteOnly));
+		f.write("qet.log('PROBE ' + JSON.stringify("
+				"qet.query('SELECT date FROM project_summary_view')));\n");
+		f.close();
+
+		QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+		env.insert(QStringLiteral("QT_QPA_PLATFORM"), QStringLiteral("offscreen"));
+		env.insert(QStringLiteral("QET_ENABLE_SCRIPTING"), QStringLiteral("1"));
+		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("LC_ALL"), QStringLiteral("en_US.UTF-8"));
+		QProcess proc;
+		proc.setProcessEnvironment(env);
+		proc.start(QStringLiteral(QET_TEST_BINARY_PATH),
+				   {QStringLiteral("--run"), path,
+					QStringLiteral(QET_EXAMPLES_DIR "/741.qet")});
+		QVERIFY(proc.waitForFinished(120000));
+		const QString out = QString::fromUtf8(proc.readAllStandardOutput()
+											  + proc.readAllStandardError());
+		QJsonArray rows;
+		for (const QString &line : out.split(QLatin1Char('\n'))) {
+			const int i = line.indexOf(QStringLiteral("PROBE "));
+			if (i >= 0)
+				rows = QJsonDocument::fromJson(line.mid(i + 6).toUtf8()).array();
+		}
+		QCOMPARE(rows.size(), 1);
+		QCOMPARE(rows.at(0).toObject().value(QStringLiteral("date")).toString(),
+				 QStringLiteral("2010-09-21"));
+	}
+};
+
+QTEST_APPLESS_MAIN(tst_dbfoliodate)
+
+#include "tst_dbfoliodate.moc"