// Copyright (C) 2021 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #ifndef QPROPERTYTESTHELPER_P_H #define QPROPERTYTESTHELPER_P_H // // W A R N I N G // ------------- // // This file is not part of the Qt API. It exists purely as an // implementation detail. This header file may change from version to // version without notice, or even be removed. // // We mean it. // #include #include #include #include #include QT_BEGIN_NAMESPACE namespace QTestPrivate { /*! \internal This helper macro is used as a wrapper around \l QVERIFY2() to provide a detailed error message in case of failure. It is intended to be used \e only in the helper functions below. The custom \a comparator method is used to check if the \a actual and \a expected values are equal or not. The macro uses a custom \a represent callback to generate the string representation of \a actual and \a expected. The error message is close to the one provided by the \l QCOMPARE() macro. Specifically the implementation is taken from the \c formatFailMessage() function, which is defined in the \c qtestresult.cpp file. */ #define QPROPERTY_TEST_COMPARISON_HELPER(actual, expected, comparator, represent) \ do { \ const size_t maxMsgLen = 1024; \ char msg[maxMsgLen] = { '\0' }; \ auto actualStr = represent(actual); \ auto expectedStr = represent(expected); \ const size_t len1 = mbstowcs(nullptr, #actual, maxMsgLen); \ const size_t len2 = mbstowcs(nullptr, #expected, maxMsgLen); \ qsnprintf(msg, maxMsgLen, "\n%s\n Actual (%s)%*s %s\n Expected (%s)%*s %s\n", \ "Comparison failed!", #actual, qMax(len1, len2) - len1 + 1, ":", \ actualStr ? actualStr : "", #expected, qMax(len1, len2) - len2 + 1, ":", \ expectedStr ? expectedStr : ""); \ delete[] actualStr; \ delete[] expectedStr; \ QVERIFY2(comparator(actual, expected), msg); \ } while (false) /*! \internal Basic testing of a bindable property. This helper function tests the behavior of bindable read/write property \a propertyName, of type \c PropertyType, in class \c TestedClass. The caller must supply an \a instance of \c TestedClass and two distinct values, \a initial and \a changed, of \c PropertyType. Since the first part of the test sets the property to \a initial, it \e {must not} be the default value of the property, or the check that it was set will be vacuous. By default \c {operator==()} is used to compare values of the property and \c {QTest::toString()} is used to generate proper error messages. If such comparison is not supported for \c PropertyType, or the comparison it supports is not appropriate to this property, a custom \a comparator can be supplied. Apart from that, a custom \a represent callback can also be specified to generate a string representation of \c PropertyType. If supplied, it must allocate its returned string using \c {new char[]}, so that it can be used in place of \l {QTest::toString()}. The \a helperConstructor method is used to create another instance of \c TestedClass. This instance is used to test for binding loops. By default, the method returns a default-constructed \c TestedClass. A custom \a helperConstructor should be provided if \c TestedClass is not default-constructible. Some very specific properties cannot be tested for binding loops. Pass a lambda that returns an \c {std::nullptr} as \a helperConstructor in such case. \note Any test calling this method will need to call \code if (QTest::currentTestFailed()) return; \endcode after doing so, if there is any later code in the test. If testing several properties in one test method, emitting a warning message saying which property failed, before returning, is a kindness to readers of the output. */ template void testReadWritePropertyBasics( TestedClass &instance, const PropertyType &initial, const PropertyType &changed, const char *propertyName, std::function comparator = [](const PropertyType &lhs, const PropertyType &rhs) { return lhs == rhs; }, std::function represent = [](const PropertyType &val) { return QTest::toString(val); }, std::function(void)> helperConstructor = []() { return std::make_unique(); }) { // get the property const QMetaObject *metaObject = instance.metaObject(); QMetaProperty metaProperty = metaObject->property(metaObject->indexOfProperty(propertyName)); QVERIFY2(metaProperty.metaType() == QMetaType::fromType(), QByteArray("Preconditions not met for ") + propertyName + "\n" "The type of initial and changed value does not match the type of the property.\n" "Please ensure that the types match exactly (convertability is not enough).\n" "You can provide the template types to the " "function explicitly to force a certain type.\n" "Expected was a " + metaProperty.metaType().name() + " but " + QMetaType::fromType().name() + " was provided."); // in case the TestedClass has setProperty()/property() methods. QObject &testedObj = static_cast(instance); QVERIFY2(metaProperty.isBindable() && metaProperty.isWritable(), "Preconditions not met for " + QByteArray(propertyName)); QScopedPointer spy(nullptr); if (metaProperty.hasNotifySignal()) spy.reset(new QSignalSpy(&instance, metaProperty.notifySignal())); testedObj.setProperty(propertyName, QVariant::fromValue(initial)); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), initial, comparator, represent); if (spy) QCOMPARE(spy->size(), 1); QUntypedBindable bindable = metaProperty.bindable(&instance); // Bind to the object's property (using both lambda and // Qt:makePropertyBinding). QProperty propObserver(changed); propObserver.setBinding(bindable.makeBinding()); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), initial, comparator, represent); QProperty propObserverLambda(changed); propObserverLambda.setBinding( [&]() { return testedObj.property(propertyName).template value(); }); QPROPERTY_TEST_COMPARISON_HELPER(propObserverLambda.value(), initial, comparator, represent); testedObj.setProperty(propertyName, QVariant::fromValue(changed)); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserverLambda.value(), changed, comparator, represent); if (spy) QCOMPARE(spy->size(), 2); // Bind object's property to other property QProperty propSetter(initial); QVERIFY(!bindable.hasBinding()); bindable.setBinding(Qt::makePropertyBinding(propSetter)); QVERIFY(bindable.hasBinding()); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), initial, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), initial, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserverLambda.value(), initial, comparator, represent); if (spy) QCOMPARE(spy->size(), 3); // Count notifications triggered; should only happen on actual change. int updateCount = 0; auto handler = bindable.onValueChanged([&updateCount]() { ++updateCount; }); Q_UNUSED(handler) propSetter.setValue(changed); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserverLambda.value(), changed, comparator, represent); QCOMPARE(updateCount, 1); if (spy) QCOMPARE(spy->size(), 4); // Test that manually setting the value (even the same one) breaks the // binding. testedObj.setProperty(propertyName, QVariant::fromValue(changed)); QVERIFY(!bindable.hasBinding()); // Setting the same value should have no impact on udpateCount. QCOMPARE(updateCount, 1); // value didn't change -> the signal should not be emitted if (spy) QCOMPARE(spy->size(), 4); // test binding loop if (std::unique_ptr helperObj = helperConstructor()) { // Reset to 'initial', so that the binding loop test could check the // 'changed' value, because some tests already rely on the 'instance' to // have the 'changed' value once this test passes testedObj.setProperty(propertyName, QVariant::fromValue(initial)); const QPropertyBinding binding([&]() { QObject *obj = static_cast(helperObj.get()); obj->setProperty(propertyName, QVariant::fromValue(changed)); return obj->property(propertyName).template value(); }, {}); bindable.setBinding(binding); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), changed, comparator, represent); QVERIFY2(!binding.error().hasError(), qPrintable(binding.error().description())); } } /*! \internal \overload This overload supports the case where the caller only needs to override the default for \a helperConstructor. It uses the defaults for all the other parameters. */ template void testReadWritePropertyBasics( TestedClass &instance, const PropertyType &initial, const PropertyType &changed, const char *propertyName, std::function(void)> helperConstructor) { testReadWritePropertyBasics( instance, initial, changed, propertyName, [](const PropertyType &lhs, const PropertyType &rhs) { return lhs == rhs; }, [](const PropertyType &val) { return QTest::toString(val); }, helperConstructor); } /*! \internal Basic testing of a bindable property that is writable only once. The write-once properties are writable properties which accept only one valid setting of the value ("write"), after which later attempts are ignored. This helper function tests the behavior of bindable write-once property \a propertyName, of type \c PropertyType, in class \c TestedClass. The caller must supply an \a instance of \c TestedClass and two distinct values, \a initial and \a changed, of \c PropertyType. The property of \a instance must not yet have been set when this function is called. The value it has before being set should be passed as \a prior and a distinct value, that this test can set it to, as \a changed. The \a bindingPreservedOnWrite parameter controls whether this function expects the binding set by this function to be preserved when setting a value directly. The default value is 'true'. By default \c {operator==()} is used to compare values of the property and \c {QTest::toString()} is used to generate proper error messages. If such comparison is not supported for \c PropertyType, or the comparison it supports is not appropriate to this property, a custom \a comparator can be supplied. Apart from that, a custom \a represent callback can also be specified to generate a string representation of \c PropertyType. If supplied, it must allocate its returned string using \c {new char[]}, so that it can be used in place of \l {QTest::toString()}. The \a helperConstructor method is used to create another instance of \c TestedClass. This instance is used to test for binding loops. By default, the method returns a default-constructed \c TestedClass. A custom \a helperConstructor should be provided if \c TestedClass is not default-constructible. Some very specific properties cannot be tested for binding loops. Pass a lambda that returns an \c {std::nullptr} as \a helperConstructor in such case. \note Any test calling this method will need to call \code if (QTest::currentTestFailed()) return; \endcode after doing so, if there is any later code in the test. If testing several properties in one test method, emitting a warning message saying which property failed, before returning, is a kindness to readers of the output. */ template void testWriteOncePropertyBasics( TestedClass &instance, const PropertyType &prior, const PropertyType &changed, const char *propertyName, bool bindingPreservedOnWrite = true, std::function comparator = [](const PropertyType &lhs, const PropertyType &rhs) { return lhs == rhs; }, std::function represent = [](const PropertyType &val) { return QTest::toString(val); }, std::function(void)> helperConstructor = []() { return std::make_unique(); }) { // get the property const QMetaObject *metaObject = instance.metaObject(); QMetaProperty metaProperty = metaObject->property(metaObject->indexOfProperty(propertyName)); // in case the TestedClass has setProperty()/property() methods. QObject &testedObj = static_cast(instance); QVERIFY2(metaProperty.metaType() == QMetaType::fromType(), QByteArray("Preconditions not met for ") + propertyName + "\n" "The type of prior and changed value does not match the type of the property.\n" "Please ensure that the types match exactly (convertability is not enough).\n" "You can provide the template types to the " "function explicitly to force a certain type.\n" "Property is " + metaProperty.metaType().name() + " but parameters are " + QMetaType::fromType().name() + ".\n"); QVERIFY2(metaProperty.isBindable(), "Preconditions not met for " + QByteArray(propertyName)); QUntypedBindable bindable = metaProperty.bindable(&instance); QScopedPointer spy(nullptr); if (metaProperty.hasNotifySignal()) spy.reset(new QSignalSpy(&instance, metaProperty.notifySignal())); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), prior, comparator, represent); QProperty propObserver; propObserver.setBinding(bindable.makeBinding()); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), prior, comparator, represent); // Create a binding that sets the 'changed' value to the property. // This also tests binding loops. QVERIFY(!bindable.hasBinding()); std::unique_ptr helperObj = helperConstructor(); QProperty propSetter(changed); // if the helperConstructor() returns nullptr const QPropertyBinding binding = helperObj ? Qt::makePropertyBinding([&]() { QObject *obj = static_cast(helperObj.get()); obj->setProperty(propertyName, QVariant::fromValue(changed)); return obj->property(propertyName).template value(); }) : Qt::makePropertyBinding(propSetter); bindable.setBinding(binding); QVERIFY(bindable.hasBinding()); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), changed, comparator, represent); if (spy) QCOMPARE(spy->size(), 1); // Attempt to set back the 'prior' value and verify that it has no effect testedObj.setProperty(propertyName, QVariant::fromValue(prior)); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), changed, comparator, represent); if (spy) QCOMPARE(spy->size(), 1); if (bindingPreservedOnWrite) QVERIFY(bindable.hasBinding()); else QVERIFY(!bindable.hasBinding()); } /*! \internal \overload This overload supports the case where the caller only needs to override the default for \a helperConstructor. It uses the defaults for all the other parameters. */ template void testWriteOncePropertyBasics( TestedClass &instance, const PropertyType &prior, const PropertyType &changed, const char *propertyName, bool bindingPreservedOnWrite, std::function(void)> helperConstructor) { testWriteOncePropertyBasics( instance, prior, changed, propertyName, bindingPreservedOnWrite, [](const PropertyType &lhs, const PropertyType &rhs) { return lhs == rhs; }, [](const PropertyType &val) { return QTest::toString(val); }, helperConstructor); } /*! \internal Basic testing of a read-only bindable property. This helper function tests the behavior of bindable read-only property \a propertyName, of type \c PropertyType, in class \c TestedClass. The caller must supply an \a instance of \c TestedClass and two distinct values, \a initial and \a changed, of \c PropertyType. When this function is called, the property's value must be \a initial. The \a mutator must, when called, cause the property's value to be revised to \a changed. By default \c {operator==()} is used to compare values of the property and \c {QTest::toString()} is used to generate proper error messages. If such comparison is not supported for \c PropertyType, or the comparison it supports is not appropriate to this property, a custom \a comparator can be supplied. Apart from that, a custom \a represent callback can also be specified to generate a string representation of \c PropertyType. If supplied, it must allocate its returned string using \c {new char[]}, so that it can be used in place of \l {QTest::toString()}. \note Any test calling this method will need to call \code if (QTest::currentTestFailed()) return; \endcode after doing so, if there is any later code in the test. If testing several properties in one test method, emitting a warning message saying which property failed, before returning, is a kindness to readers of the output. */ template void testReadOnlyPropertyBasics( TestedClass &instance, const PropertyType &initial, const PropertyType &changed, const char *propertyName, std::function mutator = []() { QFAIL("Data modifier function must be provided"); }, std::function comparator = [](const PropertyType &lhs, const PropertyType &rhs) { return lhs == rhs; }, std::function represent = [](const PropertyType &val) { return QTest::toString(val); }) { // get the property const QMetaObject *metaObject = instance.metaObject(); QMetaProperty metaProperty = metaObject->property(metaObject->indexOfProperty(propertyName)); // in case the TestedClass has setProperty()/property() methods. QObject &testedObj = static_cast(instance); QVERIFY2(metaProperty.metaType() == QMetaType::fromType(), QByteArray("Preconditions not met for ") + propertyName + "\n" "The type of initial and changed value does not match the type of the property.\n" "Please ensure that the types match exactly (convertability is not enough).\n" "You can provide the template types to the " "function explicitly to force a certain type.\n" "Expected was a " + metaProperty.metaType().name() + " but " + QMetaType::fromType().name() + " was provided."); QVERIFY2(metaProperty.isBindable(), "Preconditions not met for " + QByteArray(propertyName)); QUntypedBindable bindable = metaProperty.bindable(&instance); QScopedPointer spy(nullptr); if (metaProperty.hasNotifySignal()) spy.reset(new QSignalSpy(&instance, metaProperty.notifySignal())); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), initial, comparator, represent); // Check that attempting to bind this read-only property to another property has no effect: QProperty propSetter(initial); QVERIFY(!bindable.hasBinding()); bindable.setBinding(Qt::makePropertyBinding(propSetter)); QVERIFY(!bindable.hasBinding()); propSetter.setValue(changed); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), initial, comparator, represent); if (spy) QCOMPARE(spy->size(), 0); QProperty propObserver; propObserver.setBinding(bindable.makeBinding()); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), initial, comparator, represent); // Invoke mutator function. Now property value should be changed. mutator(); QPROPERTY_TEST_COMPARISON_HELPER( testedObj.property(propertyName).template value(), changed, comparator, represent); QPROPERTY_TEST_COMPARISON_HELPER(propObserver.value(), changed, comparator, represent); if (spy) QCOMPARE(spy->size(), 1); } } // namespace QTestPrivate QT_END_NAMESPACE #endif // QPROPERTYTESTHELPER_P_H