From 16d1ddfc42732afc6ba90df66042c7ff4be348c2 Mon Sep 17 00:00:00 2001 From: Olivier Goffart Date: Sat, 11 Mar 2017 19:39:32 +0100 Subject: moc: Support signals that return movable-only type By adding std::move where it makes sense. This is not only good for move-only types, but for any type which can be moved as it saves copies of the return value in any case. [ChangeLog][moc] Move-only types are now supported as return types of signals and slots. Change-Id: Idc9453af993e7574a6bddd4a87210eddd3da48a9 Reviewed-by: Marc Mutz --- src/corelib/kernel/qobjectdefs_impl.h | 7 +---- src/tools/moc/generator.cpp | 8 ++---- tests/auto/corelib/kernel/qobject/tst_qobject.cpp | 32 +++++++++++++++++++++++ 3 files changed, 35 insertions(+), 12 deletions(-) diff --git a/src/corelib/kernel/qobjectdefs_impl.h b/src/corelib/kernel/qobjectdefs_impl.h index bd08ca1763..3f5f2e78bb 100644 --- a/src/corelib/kernel/qobjectdefs_impl.h +++ b/src/corelib/kernel/qobjectdefs_impl.h @@ -90,14 +90,9 @@ namespace QtPrivate { explicit ApplyReturnValue(void *data_) : data(data_) {} }; template - void operator,(const T &value, const ApplyReturnValue &container) { - if (container.data) - *reinterpret_cast(container.data) = value; - } - template void operator,(T &&value, const ApplyReturnValue &container) { if (container.data) - *reinterpret_cast(container.data) = value; + *reinterpret_cast(container.data) = std::forward(value); } template void operator,(T, const ApplyReturnValue &) {} diff --git a/src/tools/moc/generator.cpp b/src/tools/moc/generator.cpp index db27067cf6..c4184929ef 100644 --- a/src/tools/moc/generator.cpp +++ b/src/tools/moc/generator.cpp @@ -1193,7 +1193,7 @@ void Generator::generateStaticMetacall() } fprintf(out, ");"); if (f.normalizedType != "void") { - fprintf(out, "\n if (_a[0]) *reinterpret_cast< %s*>(_a[0]) = _r; } ", + fprintf(out, "\n if (_a[0]) *reinterpret_cast< %s*>(_a[0]) = std::move(_r); } ", noRef(f.normalizedType).constData()); isUsed_a = true; } @@ -1506,11 +1506,7 @@ void Generator::generateSignal(FunctionDef *def,int index) fprintf(out, ")%s\n{\n", constQualifier); if (def->type.name.size() && def->normalizedType != "void") { QByteArray returnType = noRef(def->normalizedType); - if (returnType.endsWith('*')) { - fprintf(out, " %s _t0 = 0;\n", returnType.constData()); - } else { - fprintf(out, " %s _t0 = %s();\n", returnType.constData(), returnType.constData()); - } + fprintf(out, " %s _t0{};\n", returnType.constData()); } fprintf(out, " void *_a[] = { "); diff --git a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp index f44c40c27f..a645a7b5c6 100644 --- a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp +++ b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp @@ -5306,6 +5306,15 @@ void tst_QObject::connectNoDefaultConstructorArg() QVERIFY(connect(&ob, &NoDefaultContructorArguments::mySignal, &ob, &NoDefaultContructorArguments::mySlot, Qt::QueuedConnection)); } +struct MoveOnly +{ + int value; + explicit MoveOnly(int v = 1) : value(v) {} + MoveOnly(MoveOnly &&o) : value(o.value) { o.value = -1; } + MoveOnly &operator=(MoveOnly &&o) { value = o.value; o.value = -1; return *this; } + Q_DISABLE_COPY(MoveOnly); +}; + class ReturnValue : public QObject { friend class tst_QObject; Q_OBJECT @@ -5315,6 +5324,7 @@ signals: int returnInt(int); void returnVoid(int); CustomType returnCustomType(int); + MoveOnly returnMoveOnly(int); QObject *returnPointer(); public slots: @@ -5327,6 +5337,7 @@ public slots: QString returnHello() { return QStringLiteral("hello"); } QObject *returnThisSlot1() { return this; } ReturnValue *returnThisSlot2() { return this; } + MoveOnly returnMoveOnlySlot(int i) { return MoveOnly(i); } public: struct VariantFunctor { QVariant operator()(int i) { return i; } @@ -5343,6 +5354,9 @@ public: struct VoidFunctor { void operator()(int) {} }; + struct MoveOnlyFunctor { + MoveOnly operator()(int i) { return MoveOnly(i); } + }; }; QString someFunctionReturningString(int i) { @@ -5380,6 +5394,7 @@ void tst_QObject::returnValue() emit r.returnVoid(45); QCOMPARE((emit r.returnCustomType(45)).value(), CustomType().value()); QCOMPARE((emit r.returnPointer()), static_cast(0)); + QCOMPARE((emit r.returnMoveOnly(666)).value, MoveOnly().value); } { // connected to a slot returning the same type CheckInstanceCount checker; @@ -5394,6 +5409,8 @@ void tst_QObject::returnValue() QCOMPARE((emit r.returnCustomType(45)).value(), CustomType(45).value()); QVERIFY(connect(&r, &ReturnValue::returnPointer, &receiver, &ReturnValue::returnThisSlot1, type)); QCOMPARE((emit r.returnPointer()), static_cast(&receiver)); + QVERIFY(connect(&r, &ReturnValue::returnMoveOnly, &receiver, &ReturnValue::returnMoveOnlySlot, type)); + QCOMPARE((emit r.returnMoveOnly(666)).value, 666); } if (!isBlockingQueued) { // connected to simple functions or functor CheckInstanceCount checker; @@ -5412,6 +5429,10 @@ void tst_QObject::returnValue() ReturnValue::IntFunctor intFunctor; QVERIFY(connect(&r, &ReturnValue::returnInt, intFunctor)); QCOMPARE(emit r.returnInt(45), int(45)); + + ReturnValue::MoveOnlyFunctor moveOnlyFunctor; + QVERIFY(connect(&r, &ReturnValue::returnMoveOnly, moveOnlyFunctor)); + QCOMPARE((emit r.returnMoveOnly(666)).value, 666); } { // connected to a slot with different type CheckInstanceCount checker; @@ -5450,6 +5471,8 @@ void tst_QObject::returnValue() QCOMPARE((emit r.returnCustomType(45)).value(), CustomType().value()); QVERIFY(connect(&r, &ReturnValue::returnPointer, &receiver, &ReturnValue::returnVoidSlot, type)); QCOMPARE((emit r.returnPointer()), static_cast(0)); + QVERIFY(connect(&r, &ReturnValue::returnMoveOnly, &receiver, &ReturnValue::returnVoidSlot, type)); + QCOMPARE((emit r.returnMoveOnly(666)).value, MoveOnly().value); } if (!isBlockingQueued) { // queued connection should not forward the return value @@ -5465,6 +5488,8 @@ void tst_QObject::returnValue() QCOMPARE((emit r.returnCustomType(45)).value(), CustomType().value()); QVERIFY(connect(&r, &ReturnValue::returnPointer, &receiver, &ReturnValue::returnThisSlot1, Qt::QueuedConnection)); QCOMPARE((emit r.returnPointer()), static_cast(0)); + QVERIFY(connect(&r, &ReturnValue::returnMoveOnly, &receiver, &ReturnValue::returnMoveOnlySlot, Qt::QueuedConnection)); + QCOMPARE((emit r.returnMoveOnly(666)).value, MoveOnly().value); QCoreApplication::processEvents(); @@ -5548,6 +5573,8 @@ void tst_QObject::returnValue2() QCOMPARE(emit r.returnInt(45), int(45)); QVERIFY(connect(&r, SIGNAL(returnCustomType(int)), &receiver, SLOT(returnCustomTypeSlot(int)), type)); QCOMPARE((emit r.returnCustomType(45)).value(), CustomType(45).value()); + QVERIFY(connect(&r, SIGNAL(returnMoveOnly(int)), &receiver, SLOT(returnMoveOnlySlot(int)), type)); + QCOMPARE((emit r.returnMoveOnly(45)).value, 45); } { // connected to a slot returning void CheckInstanceCount checker; @@ -5560,6 +5587,8 @@ void tst_QObject::returnValue2() QCOMPARE(emit r.returnInt(45), int()); QVERIFY(connect(&r, SIGNAL(returnCustomType(int)), &receiver, SLOT(returnVoidSlot()), type)); QCOMPARE((emit r.returnCustomType(45)).value(), CustomType().value()); + QVERIFY(connect(&r, SIGNAL(returnMoveOnly(int)), &receiver, SLOT(returnVoidSlot()), type)); + QCOMPARE((emit r.returnMoveOnly(45)).value, MoveOnly().value); } if (!isBlockingQueued) { // queued connection should not forward the return value @@ -5573,6 +5602,9 @@ void tst_QObject::returnValue2() QCOMPARE(emit r.returnInt(45), int()); QVERIFY(connect(&r, SIGNAL(returnCustomType(int)), &receiver, SLOT(returnCustomTypeSlot(int)), Qt::QueuedConnection)); QCOMPARE((emit r.returnCustomType(45)).value(), CustomType().value()); + QVERIFY(connect(&r, SIGNAL(returnMoveOnly(int)), &receiver, SLOT(returnMoveOnlySlot(int)), Qt::QueuedConnection)); + QCOMPARE((emit r.returnMoveOnly(45)).value, MoveOnly().value); + QCoreApplication::processEvents(); //Queued conneciton with different return type should be safe -- cgit v1.2.3