Required properties: Allow required default properties

This was already possible from C++, this change adds the required
changes to the grammar to allow declaring required default properties
in QML.

Change-Id: I76cb4d70e573bf161676da8295ab257fe95ed4ae
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

9 files changed, 64 insertions, 8 deletions

diff --git a/src/qml/parser/qqmljs.g b/src/qml/parser/qqmljs.g
index 397c0b51a5..2b00caf378 100644
--- a/src/qml/parser/qqmljs.g
+++ b/src/qml/parser/qqmljs.g
@@ -1247,6 +1247,31 @@ UiObjectMember: T_DEFAULT UiObjectMemberListPropertyNoInitialiser;
     } break;
 ./
 
+UiObjectMember: T_DEFAULT T_REQUIRED UiObjectMemberPropertyNoInitialiser;
+/.
+    case $rule_number: {
+        AST::UiPublicMember *node = sym(3).UiPublicMember;
+        node->isDefaultMember = true;
+        node->defaultToken = loc(1);
+        node->isRequired = true;
+        node->requiredToken = loc(2);
+        sym(1).Node = node;
+    } break;
+./
+
+
+UiObjectMember: T_REQUIRED T_DEFAULT UiObjectMemberPropertyNoInitialiser;
+/.
+    case $rule_number: {
+        AST::UiPublicMember *node = sym(3).UiPublicMember;
+        node->isDefaultMember = true;
+        node->defaultToken = loc(2);
+        node->isRequired = true;
+        node->requiredToken = loc(1);
+        sym(1).Node = node;
+    } break;
+./
+
 OptionalSemicolon: | Semicolon;
 /.
 /* we need OptionalSemicolon because UiScriptStatement might already parse the last semicolon
diff --git a/tests/auto/qml/qqmlcomponent/data/RequiredDefault.qml b/tests/auto/qml/qqmlcomponent/data/RequiredDefault.qml
new file mode 100644
index 0000000000..7e8f225a52
--- /dev/null
+++ b/tests/auto/qml/qqmlcomponent/data/RequiredDefault.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.15
+
+Item {
+    required default property Text requiredDefault
+}
diff --git a/tests/auto/qml/qqmlcomponent/data/requiredDefault.1.qml b/tests/auto/qml/qqmlcomponent/data/requiredDefault.1.qml
new file mode 100644
index 0000000000..68dff22f33
--- /dev/null
+++ b/tests/auto/qml/qqmlcomponent/data/requiredDefault.1.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.15
+
+RequiredDefault {
+    Text {text: "Hello, world!"}
+}
diff --git a/tests/auto/qml/qqmlcomponent/data/requiredDefault.2.qml b/tests/auto/qml/qqmlcomponent/data/requiredDefault.2.qml
new file mode 100644
index 0000000000..a6c4e8ea3f
--- /dev/null
+++ b/tests/auto/qml/qqmlcomponent/data/requiredDefault.2.qml
@@ -0,0 +1,3 @@
+import QtQuick 2.15
+
+RequiredDefault { }
diff --git a/tests/auto/qml/qqmlcomponent/data/requiredDefault.3.qml b/tests/auto/qml/qqmlcomponent/data/requiredDefault.3.qml
new file mode 100644
index 0000000000..19b3271858
--- /dev/null
+++ b/tests/auto/qml/qqmlcomponent/data/requiredDefault.3.qml
@@ -0,0 +1,6 @@
+import QtQuick 2.15
+import qt.test 1.0
+
+RequiredDefaultCpp {
+    Text {text: "Hello, world!"}
+}
diff --git a/tests/auto/qml/qqmlcomponent/data/requiredDefault.4.qml b/tests/auto/qml/qqmlcomponent/data/requiredDefault.4.qml
new file mode 100644
index 0000000000..acd56db328
--- /dev/null
+++ b/tests/auto/qml/qqmlcomponent/data/requiredDefault.4.qml
@@ -0,0 +1,4 @@
+import QtQuick 2.15
+import qt.test 1.0
+
+RequiredDefaultCpp { }
diff --git a/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp b/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
index 2acc62ca28..43cbd93396 100644
--- a/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
+++ b/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
@@ -671,8 +671,20 @@ void tst_qqmlcomponent::setDataNoEngineNoSegfault()
     QVERIFY(!c);
 }
 
+class RequiredDefaultCpp : public QObject
+{
+    Q_OBJECT
+public:
+    Q_PROPERTY(QQuickItem *defaultProperty MEMBER m_defaultProperty NOTIFY defaultPropertyChanged REQUIRED)
+    Q_SIGNAL void defaultPropertyChanged();
+    Q_CLASSINFO("DefaultProperty", "defaultProperty")
+private:
+    QQuickItem *m_defaultProperty = nullptr;
+};
+
 void tst_qqmlcomponent::testRequiredProperties_data()
 {
+    qmlRegisterType<RequiredDefaultCpp>("qt.test", 1, 0, "RequiredDefaultCpp");
     QTest::addColumn<QUrl>("testFile");
     QTest::addColumn<bool>("shouldSucceed");
     QTest::addColumn<QString>("errorMsg");
@@ -687,6 +699,10 @@ void tst_qqmlcomponent::testRequiredProperties_data()
     QTest::addRow("setLater") << testFileUrl("requiredSetLater.qml") << true << "";
     QTest::addRow("setViaAliasToSubcomponent") << testFileUrl("setViaAliasToSubcomponent.qml") << true << "";
     QTest::addRow("aliasToSubcomponentNotSet") << testFileUrl("aliasToSubcomponentNotSet.qml") << false << "It can be set via the alias property i_alias";
+    QTest::addRow("required default set") << testFileUrl("requiredDefault.1.qml") << true << "";
+    QTest::addRow("required default not set") << testFileUrl("requiredDefault.2.qml") << false << "Required property requiredDefault was not initialized";
+    QTest::addRow("required default set (C++)") << testFileUrl("requiredDefault.3.qml") << true << "";
+    QTest::addRow("required default not set (C++)") << testFileUrl("requiredDefault.4.qml") << false << "Required property defaultProperty was not initialized";
 }
 
 
diff --git a/tests/auto/qml/qqmllanguage/data/requiredProperties.3.qml b/tests/auto/qml/qqmllanguage/data/requiredProperties.3.qml
deleted file mode 100644
index 534322215f..0000000000
--- a/tests/auto/qml/qqmllanguage/data/requiredProperties.3.qml
+++ /dev/null
@@ -1,4 +0,0 @@
-import QtQuick 2.13
-Item {
-    default required property int test // cannot have required default property
-}
diff --git a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
index 64696e7f3f..5027c0825f 100644
--- a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
+++ b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
@@ -1675,10 +1675,6 @@ void tst_qqmllanguage::requiredProperty()
         QQmlComponent component(&engine, testFileUrl("requiredProperties.2.qml"));
         QVERIFY(!component.errors().empty());
     }
-    {
-        QQmlComponent component(&engine, testFileUrl("requiredProperties.3.qml"));
-        QVERIFY(!component.errors().empty());
-    }
 }
 
 class MyClassWithRequiredProperty : public QObject