test: add test for maximum history in database settings

This commit adds a test to the TestGui::testDatabaseSettings function for the history maximum items and maximum size settings.
The test opens the database settings dialog, disables the history items and size settings, saves the changes, reopens the dialog, and then cancels without making any changes to load the default values. The test ensures that the default values are loaded correctly.

tests/gui/TestGui.cpp

@@ -1466,6 +1466,7 @@ void TestGui::testDatabaseSettings()
     auto* dbSettingsStackedWidget = dbSettingsDialog->findChild<QStackedWidget*>("stackedWidget");
     auto* transformRoundsSpinBox = dbSettingsDialog->findChild<QSpinBox*>("transformRoundsSpinBox");
     auto advancedToggle = dbSettingsDialog->findChild<QCheckBox*>("advancedSettingsToggle");
+    auto* dbSettingsButtonBox = dbSettingsDialog->findChild<QDialogButtonBox*>("buttonBox");
 
     advancedToggle->setChecked(true);
     QApplication::processEvents();
@@ -1477,6 +1478,27 @@ void TestGui::testDatabaseSettings()
     QTest::keyClick(transformRoundsSpinBox, Qt::Key_Enter);
     QTRY_COMPARE(m_db->kdf()->rounds(), 123456);
 
+    // test disable and default values for maximum history items and size
+    triggerAction("actionDatabaseSettings");
+    auto* historyMaxItemsCheckBox = dbSettingsDialog->findChild<QCheckBox*>("historyMaxItemsCheckBox");
+    auto* historyMaxItemsSpinBox = dbSettingsDialog->findChild<QSpinBox*>("historyMaxItemsSpinBox");
+    auto* historyMaxSizeCheckBox = dbSettingsDialog->findChild<QCheckBox*>("historyMaxSizeCheckBox");
+    auto* historyMaxSizeSpinBox = dbSettingsDialog->findChild<QSpinBox*>("historyMaxSizeSpinBox");
+    // test defaults
+    QCOMPARE(historyMaxItemsSpinBox->value(), Metadata::DefaultHistoryMaxItems);
+    QCOMPARE(historyMaxSizeSpinBox->value(), qRound(Metadata::DefaultHistoryMaxSize / qreal(1024 * 1024)));
+    // disable and test setting as well
+    historyMaxItemsCheckBox->setChecked(false);
+    historyMaxSizeCheckBox->setChecked(false);
+    QTest::mouseClick(dbSettingsButtonBox->button(QDialogButtonBox::Ok), Qt::LeftButton);
+    QTRY_COMPARE(m_db->metadata()->historyMaxItems(), -1);
+    QTRY_COMPARE(m_db->metadata()->historyMaxSize(), -1);
+    // then open to check the saved disabled state in gui
+    triggerAction("actionDatabaseSettings");
+    QCOMPARE(historyMaxItemsCheckBox->isChecked(), false);
+    QCOMPARE(historyMaxSizeCheckBox->isChecked(), false);
+    QTest::mouseClick(dbSettingsButtonBox->button(QDialogButtonBox::Cancel), Qt::LeftButton);
+
     checkSaveDatabase();
 }