Honour the resettable flag of aliased properties

Previously, alias properties were not considered isResettable even
if the property they alias is resettable.  This commit ensures that
the IsResettable flag is set for alias properties iff the aliased
property is resettable, and that it is honoured during property
reset operations.

Task-number: QTBUG-18182
Change-Id: I9cab11923a952df72e976a48489a78b24a34314f
Reviewed-on: http://codereview.qt.nokia.com/1471
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Aaron Kennedy <aaron.kennedy@nokia.com>

7 files changed, 152 insertions, 0 deletions

diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/AliasPropertyComponent.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/AliasPropertyComponent.qml
new file mode 100644
index 0000000000..9135e79469
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/AliasPropertyComponent.qml
@@ -0,0 +1,17 @@
+import QtQuick 2.0
+
+Item {
+    id: apc
+    property alias sourceComponent: loader.sourceComponent
+
+    Component {
+        id: redSquare
+        Rectangle { color: "red"; width: 10; height: 10 }
+    }
+
+    Loader {
+        id: loader
+        objectName: "loader"
+        sourceComponent: redSquare
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.1.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.1.qml
new file mode 100644
index 0000000000..a27c16dd2e
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.1.qml
@@ -0,0 +1,23 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+Item {
+    id: first
+    property bool aliasIsUndefined: false
+    property alias sourceComponentAlias: loader.sourceComponent
+
+    Component {
+        id: redSquare
+        Rectangle { color: "red"; width: 10; height: 10 }
+    }
+
+    Loader {
+        id: loader
+        sourceComponent: redSquare
+    }
+
+    function resetAliased() {
+        loader.sourceComponent = undefined;
+        aliasIsUndefined = (sourceComponentAlias == undefined);
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.2.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.2.qml
new file mode 100644
index 0000000000..fa2bb5eb6d
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.2.qml
@@ -0,0 +1,23 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+Item {
+    id: first
+    property bool loaderSourceComponentIsUndefined: false
+    property alias sourceComponentAlias: loader.sourceComponent
+
+    Component {
+        id: redSquare
+        Rectangle { color: "red"; width: 10; height: 10 }
+    }
+
+    Loader {
+        id: loader
+        sourceComponent: redSquare
+    }
+
+    function resetAlias() {
+        sourceComponentAlias = undefined;
+        loaderSourceComponentIsUndefined = (loader.sourceComponent == undefined);
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.3.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.3.qml
new file mode 100644
index 0000000000..4fa6861b08
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.3.qml
@@ -0,0 +1,31 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+Item {
+    id: first
+    property bool loaderTwoSourceComponentIsUndefined: false
+    property bool loaderOneSourceComponentIsUndefined: false
+    property alias sourceComponentAlias: loaderOne.sourceComponent
+
+    Component {
+        id: redSquare
+        Rectangle { color: "red"; width: 10; height: 10 }
+    }
+
+    Loader {
+        id: loaderOne
+        sourceComponent: loaderTwo.sourceComponent
+    }
+
+    Loader {
+        id: loaderTwo
+        sourceComponent: redSquare
+        x: 15
+    }
+
+    function resetAlias() {
+        sourceComponentAlias = undefined; // loaderOne.sourceComponent should be set to undefined instead of l2.sc
+        loaderOneSourceComponentIsUndefined = (loaderOne.sourceComponent == undefined); // should be true
+        loaderTwoSourceComponentIsUndefined = (loaderTwo.sourceComponent == undefined); // should be false
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.4.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.4.qml
new file mode 100644
index 0000000000..56fcc2ec7c
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.4.qml
@@ -0,0 +1,26 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+Item {
+    id: first
+    property alias sourceComponentAlias: loader.sourceComponent
+
+    Component {
+        id: redSquare
+        Rectangle { color: "red"; width: 10; height: 10 }
+    }
+
+    Loader {
+        id: loader
+        objectName: "loader"
+        sourceComponent: redSquare
+    }
+
+    function resetAlias() {
+        sourceComponentAlias = undefined; // ensure we don't crash after deletion of loader.
+    }
+
+    function setAlias() {
+        sourceComponentAlias = redSquare;
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.5.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.5.qml
new file mode 100644
index 0000000000..a046bbf504
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.5.qml
@@ -0,0 +1,14 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+Item {
+    id: root
+
+    AliasPropertyComponent {
+        sourceComponent: returnsUndefined()
+    }
+
+    function returnsUndefined() {
+        return undefined;
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.error.1.qml b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.error.1.qml
new file mode 100644
index 0000000000..22311d6bb3
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/aliasreset/aliasPropertyReset.error.1.qml
@@ -0,0 +1,18 @@
+import QtQuick 1.0
+import Qt.test 1.0
+
+MyQmlObject {
+    id: first
+    property bool aliasedIntIsUndefined: false
+    property alias intAlias: objprop.intp
+
+    objectProperty: QtObject {
+        id: objprop
+        property int intp: 12
+    }
+
+    function resetAlias() {
+        intAlias = undefined; // should error
+        aliasedIntIsUndefined = (objprop.intp == undefined);
+    }
+}