Add QQmlEngine::trimComponentCache()

Allow unused data in the engine's component cache to be safely discarded
so that the memory can be freed for other purposes.

Unloading of scripts that are no longer required after trimming unused
components is not yet supported.

Task-number: QTBUG-25653
Change-Id: I37bc9d5592eeb5edceeb34d010a555dcffd11cea
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

60 files changed, 1749 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlengine/data/EmptyAggregateEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyAggregateEmptyComponent.qml
new file mode 100644
index 0000000000..76a0e32335
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyAggregateEmptyComponent.qml
@@ -0,0 +1,6 @@
+import QtQuick 2.0
+
+Item {
+    EmptyComponent {
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyAggregateVMEComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyAggregateVMEComponent.qml
new file mode 100644
index 0000000000..7e6821ee48
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyAggregateVMEComponent.qml
@@ -0,0 +1,6 @@
+import QtQuick 2.0
+
+Item {
+    VMEComponent {
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyComponent.qml
new file mode 100644
index 0000000000..459c82afbb
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyComponent.qml
@@ -0,0 +1,4 @@
+import QtQuick 2.0
+
+Item {
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyExtendEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyExtendEmptyComponent.qml
new file mode 100644
index 0000000000..728b8e7798
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyExtendEmptyComponent.qml
@@ -0,0 +1,4 @@
+import QtQuick 2.0
+
+EmptyComponent {
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyExtendVMEComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyExtendVMEComponent.qml
new file mode 100644
index 0000000000..88efc731a0
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyExtendVMEComponent.qml
@@ -0,0 +1,4 @@
+import QtQuick 2.0
+
+VMEComponent {
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyPropertyEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyPropertyEmptyComponent.qml
new file mode 100644
index 0000000000..293a8e713e
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyPropertyEmptyComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+Item {
+    property EmptyComponent p: EmptyComponent {}
+}
diff --git a/tests/auto/qml/qqmlengine/data/EmptyPropertyVMEComponent.qml b/tests/auto/qml/qqmlengine/data/EmptyPropertyVMEComponent.qml
new file mode 100644
index 0000000000..8444edc829
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/EmptyPropertyVMEComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+Item {
+    property VMEComponent p: VMEComponent {}
+}
diff --git a/tests/auto/qml/qqmlengine/data/NestedEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/NestedEmptyComponent.qml
new file mode 100644
index 0000000000..728b8e7798
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/NestedEmptyComponent.qml
@@ -0,0 +1,4 @@
+import QtQuick 2.0
+
+EmptyComponent {
+}
diff --git a/tests/auto/qml/qqmlengine/data/NestedVMEComponent.qml b/tests/auto/qml/qqmlengine/data/NestedVMEComponent.qml
new file mode 100644
index 0000000000..fd4f15482c
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/NestedVMEComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+VMEComponent {
+    property real pi: 3.1415927
+}
diff --git a/tests/auto/qml/qqmlengine/data/ScriptComponent.qml b/tests/auto/qml/qqmlengine/data/ScriptComponent.qml
new file mode 100644
index 0000000000..3fb9a10e85
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/ScriptComponent.qml
@@ -0,0 +1,6 @@
+import QtQuick 2.0
+import "script.js" as JS
+
+VMEExtendVMEComponent {
+    function getSomething() { return JS.getSomething() }
+}
diff --git a/tests/auto/qml/qqmlengine/data/TopLevelComponent.qml b/tests/auto/qml/qqmlengine/data/TopLevelComponent.qml
new file mode 100644
index 0000000000..dea8a9ce2e
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/TopLevelComponent.qml
@@ -0,0 +1,6 @@
+import QtQuick 2.0
+
+Component {
+    VMEExtendVMEComponent {
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEAggregateEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/VMEAggregateEmptyComponent.qml
new file mode 100644
index 0000000000..a34a036471
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEAggregateEmptyComponent.qml
@@ -0,0 +1,8 @@
+import QtQuick 2.0
+
+Item {
+    property string bar: 'baz'
+
+    EmptyComponent {
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEAggregateVMEComponent.qml b/tests/auto/qml/qqmlengine/data/VMEAggregateVMEComponent.qml
new file mode 100644
index 0000000000..4bacdf8042
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEAggregateVMEComponent.qml
@@ -0,0 +1,8 @@
+import QtQuick 2.0
+
+Item {
+    property string foo: 'bar'
+
+    VMEComponent {
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEComponent.qml b/tests/auto/qml/qqmlengine/data/VMEComponent.qml
new file mode 100644
index 0000000000..0a43a08711
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+Item {
+    property string foo: 'bar'
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEExtendEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/VMEExtendEmptyComponent.qml
new file mode 100644
index 0000000000..df81f6bb88
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEExtendEmptyComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+EmptyComponent {
+    property string bar: 'baz'
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEExtendVMEComponent.qml b/tests/auto/qml/qqmlengine/data/VMEExtendVMEComponent.qml
new file mode 100644
index 0000000000..bf7a2ecdc2
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEExtendVMEComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick 2.0
+
+VMEComponent {
+    property string bar: 'baz'
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEPropertyEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/VMEPropertyEmptyComponent.qml
new file mode 100644
index 0000000000..4ead1e0088
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEPropertyEmptyComponent.qml
@@ -0,0 +1,7 @@
+import QtQuick 2.0
+
+Item {
+    property string foo: 'bar'
+
+    property EmptyComponent p: EmptyComponent {}
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMEPropertyVMEComponent.qml b/tests/auto/qml/qqmlengine/data/VMEPropertyVMEComponent.qml
new file mode 100644
index 0000000000..88867f29fc
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMEPropertyVMEComponent.qml
@@ -0,0 +1,7 @@
+import QtQuick 2.0
+
+Item {
+    property string foo: 'bar'
+
+    property VMEComponent p: VMEComponent {}
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMETransientEmptyComponent.qml b/tests/auto/qml/qqmlengine/data/VMETransientEmptyComponent.qml
new file mode 100644
index 0000000000..487025f67f
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMETransientEmptyComponent.qml
@@ -0,0 +1,15 @@
+import QtQuick 2.0
+
+Item {
+    property var p: null
+
+    Component.onCompleted: {
+        var c = Qt.createComponent('EmptyComponent.qml')
+        p = c.createObject()
+        c.destroy()
+    }
+
+    Component.onDestruction: {
+        p.destroy()
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/VMETransientVMEComponent.qml b/tests/auto/qml/qqmlengine/data/VMETransientVMEComponent.qml
new file mode 100644
index 0000000000..8f29b53ca5
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/VMETransientVMEComponent.qml
@@ -0,0 +1,15 @@
+import QtQuick 2.0
+
+Item {
+    property var p: null
+
+    Component.onCompleted: {
+        var c = Qt.createComponent('VMEComponent.qml')
+        p = c.createObject()
+        c.destroy()
+    }
+
+    Component.onDestruction: {
+        p.destroy()
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/script.js b/tests/auto/qml/qqmlengine/data/script.js
new file mode 100644
index 0000000000..616de3ddd7
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/script.js
@@ -0,0 +1 @@
+function getSomething() { return 'https://example.org/' }
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.1.qml
new file mode 100644
index 0000000000..812242f146
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.1.qml
@@ -0,0 +1,38 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyAggregateEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.2.qml
new file mode 100644
index 0000000000..a171ee6b28
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyAggregateEmptyComponent.2.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyAggregateEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 3')
+        if (obj.x == undefined) return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyAggregateEmptyComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.1.qml
new file mode 100644
index 0000000000..de40284452
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyAggregateVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.2.qml
new file mode 100644
index 0000000000..4939087b31
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyAggregateVMEComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyAggregateVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.x == undefined) return reportError('Invalid object 5')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyAggregateVMEComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyComponent.1.qml
new file mode 100644
index 0000000000..5cee0341fe
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyComponent.1.qml
@@ -0,0 +1,34 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyComponent.2.qml
new file mode 100644
index 0000000000..2a13822fab
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyComponent.2.qml
@@ -0,0 +1,36 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 3')
+        if (obj.x == undefined) return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.1.qml
new file mode 100644
index 0000000000..2f238175fa
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.1.qml
@@ -0,0 +1,38 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyExtendEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.2.qml
new file mode 100644
index 0000000000..d36e95fec3
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyExtendEmptyComponent.2.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyExtendEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 3')
+        if (obj.x == undefined) return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyExtendEmptyComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.1.qml
new file mode 100644
index 0000000000..53dd5a17e9
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.foo != 'bar') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.2.qml
new file mode 100644
index 0000000000..e5cd7d60de
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyExtendVMEComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.foo != 'bar') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.x == undefined) return reportError('Invalid object 5')
+        if (obj.foo != 'bar') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyExtendVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.1.qml
new file mode 100644
index 0000000000..d98aef2932
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.1.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyPropertyEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.2.qml
new file mode 100644
index 0000000000..7f438aa995
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyPropertyEmptyComponent.2.qml
@@ -0,0 +1,44 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('EmptyPropertyEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.x == undefined) return reportError('Invalid object 6')
+        if (obj.p == undefined) return reportError('Invalid object 7')
+        if (obj.p.x == undefined) return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyPropertyEmptyComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.1.qml
new file mode 100644
index 0000000000..83d6226e83
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.1.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyPropertyVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.2.qml
new file mode 100644
index 0000000000..98dfb7241b
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testEmptyPropertyVMEComponent.2.qml
@@ -0,0 +1,44 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('EmptyPropertyVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.x == undefined) return reportError('Invalid object 6')
+        if (obj.p == undefined) return reportError('Invalid object 7')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testEmptyPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('EmptyPropertyVMEComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testIncubatedComponent.qml b/tests/auto/qml/qqmlengine/data/testIncubatedComponent.qml
new file mode 100644
index 0000000000..50af9c4f16
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testIncubatedComponent.qml
@@ -0,0 +1,51 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testIncubatedComponent.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var c = Qt.createComponent('VMEExtendVMEComponent.qml')
+        var i = c.incubateObject(null, {}, Qt.Asynchronous)
+
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testIncubatedComponent.qml')) return reportError('Test component unloaded 1')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        c.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testIncubatedComponent.qml')) return reportError('Test component unloaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        i.onStatusChanged = function(status) {
+            if (status != Component.Ready) return;
+            if (i.object == null) return reportError('Extend component not created')
+            if (i.object.foo != 'bar') return reportError('Invalid object')
+            if (i.object.bar != 'baz') return reportError('Invalid object 2')
+
+            componentCache.trim()
+            if (!componentCache.isTypeLoaded('testIncubatedComponent.qml')) return reportError('Test component unloaded 3')
+            if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded 2')
+            if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded 2')
+
+            i.object.destroy()
+            componentCache.trim()
+            if (!componentCache.isTypeLoaded('testIncubatedComponent.qml')) return reportError('Test component unloaded 4')
+            if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+            if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+            success = true
+        }
+
+        componentCache.beginIncubation()
+        componentCache.waitForIncubation();
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testLoaderComponent.qml b/tests/auto/qml/qqmlengine/data/testLoaderComponent.qml
new file mode 100644
index 0000000000..a04ca41c26
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testLoaderComponent.qml
@@ -0,0 +1,62 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testLoaderComponent.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        loader.source = 'VMEExtendVMEComponent.qml'
+    }
+
+    Loader {
+        id: loader
+
+        property bool previouslyLoaded: false
+        onLoaded: {
+            if (!previouslyLoaded) {
+                componentCache.trim()
+                if (!componentCache.isTypeLoaded('testLoaderComponent.qml')) return reportError('Test component not loaded 2')
+                if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+                if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+                if (!item) return reportError('Invalid item')
+                if (item.foo != 'bar') return reportError('Invalid item 2')
+                if (item.bar != 'baz') return reportError('Invalid item 3')
+
+                loader.source = ''
+                componentCache.trim()
+                if (!componentCache.isTypeLoaded('testLoaderComponent.qml')) return reportError('Test component not loaded 3')
+                if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+                if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+                if (item) return reportError('Item not invalidated')
+
+                previouslyLoaded = true
+                loader.source = 'VMEExtendVMEComponent.qml'
+            } else {
+                componentCache.trim()
+                if (!componentCache.isTypeLoaded('testLoaderComponent.qml')) return reportError('Test component not loaded 4')
+                if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not reloaded')
+                if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not reloaded')
+
+                if (!item) return reportError('Invalid item 4')
+                if (item.foo != 'bar') return reportError('Invalid item 5')
+                if (item.bar != 'baz') return reportError('Invalid item 6')
+
+                loader.source = ''
+                componentCache.trim()
+                if (!componentCache.isTypeLoaded('testLoaderComponent.qml')) return reportError('Test component not loaded 5')
+                if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded 2')
+                if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded 2')
+                if (item) return reportError('Item not invalidated 2')
+
+                success = true
+            }
+        }
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testReloadComponent.qml b/tests/auto/qml/qqmlengine/data/testReloadComponent.qml
new file mode 100644
index 0000000000..74442108cd
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testReloadComponent.qml
@@ -0,0 +1,52 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testReloadComponent.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testReloadComponent.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        obj.destroy()
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testReloadComponent.qml')) return reportError('Test component not loaded 3')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testReloadComponent.qml')) return reportError('Test component not loaded 4')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not reloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not reloaded')
+
+        obj = comp.createObject()
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.foo != 'bar') return reportError('Invalid object 5')
+        if (obj.bar != 'baz') return reportError('Invalid object 6')
+
+        obj.destroy()
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testReloadComponent.qml')) return reportError('Test component not loaded 5')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded 2')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded 2')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testScriptComponent.qml b/tests/auto/qml/qqmlengine/data/testScriptComponent.qml
new file mode 100644
index 0000000000..b33eb48461
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testScriptComponent.qml
@@ -0,0 +1,43 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testScriptComponent.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('ScriptComponent.qml')) return reportError('Script component already loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+        if (componentCache.isScriptLoaded('script.js')) return reportError('Script file already loaded')
+
+        var comp = Qt.createComponent('ScriptComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testScriptComponent.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('ScriptComponent.qml')) return reportError('Script component not loaded')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+        if (!componentCache.isScriptLoaded('script.js')) return reportError('Script file not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+        if (obj.getSomething() != 'https://example.org/') return reportError('Invalid object 4')
+
+        obj.destroy()
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testScriptComponent.qml')) return reportError('Test component not loaded 3')
+        if (componentCache.isTypeLoaded('ScriptComponent.qml')) return reportError('Script component not unloaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        // Script unloading is not currently implemented
+        //if (componentCache.isScriptLoaded('script.js')) return reportError('Script file already loaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testTopLevelComponent.qml b/tests/auto/qml/qqmlengine/data/testTopLevelComponent.qml
new file mode 100644
index 0000000000..6cf8ec4203
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testTopLevelComponent.qml
@@ -0,0 +1,50 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTopLevelComponent.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('TopLevelComponent.qml')) return reportError('Top-level component already loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('TopLevelComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTopLevelComponent.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('TopLevelComponent.qml')) return reportError('Top-level component not loaded')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var internalComp = comp.createObject()
+        if (!internalComp) return reportError('Invalid component')
+
+        var obj = internalComp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        internalComp.destroy()
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTopLevelComponent.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('TopLevelComponent.qml')) return reportError('Top-level component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.foo != 'bar') return reportError('Invalid object 5')
+        if (obj.bar != 'baz') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTopLevelComponent.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('TopLevelComponent.qml')) return reportError('Top-level component not unloaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testTransientComponent.1.qml b/tests/auto/qml/qqmlengine/data/testTransientComponent.1.qml
new file mode 100644
index 0000000000..d3e6ffd7cf
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testTransientComponent.1.qml
@@ -0,0 +1,34 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return
+        if (obj.foo != 'bar') return reportError('Invalid object')
+        if (obj.bar != 'baz') return reportError('Invalid object 2')
+
+        obj.destroy()
+        if (!componentCache.isTypeLoaded('testTransientComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testTransientComponent.2.qml b/tests/auto/qml/qqmlengine/data/testTransientComponent.2.qml
new file mode 100644
index 0000000000..acb0113e61
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testTransientComponent.2.qml
@@ -0,0 +1,36 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return
+        if (obj.foo != 'bar') return reportError('Invalid object')
+        if (obj.bar != 'baz') return reportError('Invalid object 2')
+
+        comp.destroy()
+        if (!componentCache.isTypeLoaded('testTransientComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component already unloaded')
+        if (obj.foo != 'bar') return reportError('Invalid object 3')
+        if (obj.bar != 'baz') return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testTransientComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Transient component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.1.qml
new file mode 100644
index 0000000000..a5beede469
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEAggregateEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.children[0].x == undefined) return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.2.qml
new file mode 100644
index 0000000000..4c8e52f251
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEAggregateEmptyComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEAggregateEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.children[0].x == undefined) return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.children[0].x == undefined) return reportError('Invalid object 5')
+        if (obj.bar != 'baz') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEAggregateEmptyComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.1.qml
new file mode 100644
index 0000000000..983d6e824c
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEAggregateVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.2.qml
new file mode 100644
index 0000000000..fc8e5a0cd4
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEAggregateVMEComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Aggregate component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEAggregateVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object r4')
+        if (obj.foo != 'bar') return reportError('Invalid object 5')
+        if (obj.children[0].foo != 'bar') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEAggregateVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEAggregateVMEComponent.qml')) return reportError('Aggregate component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEComponent.1.qml
new file mode 100644
index 0000000000..fcfd05c51f
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEComponent.1.qml
@@ -0,0 +1,34 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEComponent.2.qml
new file mode 100644
index 0000000000..f434406eec
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEComponent.2.qml
@@ -0,0 +1,36 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 3')
+        if (obj.foo != 'bar') return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.1.qml
new file mode 100644
index 0000000000..1dcaec90e6
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.2.qml
new file mode 100644
index 0000000000..fd7d7e454c
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEExtendEmptyComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.x == undefined) return reportError('Invalid object 5')
+        if (obj.bar != 'baz') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendEmptyComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.1.qml
new file mode 100644
index 0000000000..d2dab32fc9
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.1.qml
@@ -0,0 +1,39 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.2.qml
new file mode 100644
index 0000000000..813e43896c
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEExtendVMEComponent.2.qml
@@ -0,0 +1,42 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEExtendVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.bar != 'baz') return reportError('Invalid object 3')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 4')
+        if (obj.foo != 'bar') return reportError('Invalid object 5')
+        if (obj.bar != 'baz') return reportError('Invalid object 6')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEExtendVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEExtendVMEComponent.qml')) return reportError('Extend component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.1.qml
new file mode 100644
index 0000000000..c6f0b7928b
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.1.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEPropertyEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.2.qml
new file mode 100644
index 0000000000..255138520c
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEPropertyEmptyComponent.2.qml
@@ -0,0 +1,44 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMEPropertyEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.foo != 'bar') return reportError('Invalid object 6')
+        if (obj.p == undefined) return reportError('Invalid object 7')
+        if (obj.p.x == undefined) return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEPropertyEmptyComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.1.qml
new file mode 100644
index 0000000000..0ad59b32d3
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.1.qml
@@ -0,0 +1,40 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEPropertyVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.2.qml
new file mode 100644
index 0000000000..60f72a92fe
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMEPropertyVMEComponent.2.qml
@@ -0,0 +1,44 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMEPropertyVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component not loaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.foo != 'bar') return reportError('Invalid object 2')
+        if (obj.p == undefined) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.foo != 'bar') return reportError('Invalid object 6')
+        if (obj.p == undefined) return reportError('Invalid object 7')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMEPropertyVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMEPropertyVMEComponent.qml')) return reportError('Property component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.1.qml
new file mode 100644
index 0000000000..6c7f959f49
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.1.qml
@@ -0,0 +1,41 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMETransientEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component not loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (!obj.p) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component already unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded 2')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.2.qml
new file mode 100644
index 0000000000..86060c3998
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMETransientEmptyComponent.2.qml
@@ -0,0 +1,45 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component already loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var comp = Qt.createComponent('VMETransientEmptyComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component not loaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (!obj.p) return reportError('Invalid object 3')
+        if (obj.p.x == undefined) return reportError('Invalid object 4')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not loaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component already unloaded')
+        if (!componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.x == undefined) return reportError('Invalid object 6')
+        if (!obj.p) return reportError('Invalid object 7')
+        if (obj.p.x == undefined) return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientEmptyComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMETransientEmptyComponent.qml')) return reportError('Transient component not unloaded')
+        if (componentCache.isTypeLoaded('EmptyComponent.qml')) return reportError('Empty component not unloaded')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.1.qml b/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.1.qml
new file mode 100644
index 0000000000..c50fd70dec
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.1.qml
@@ -0,0 +1,41 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.1.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMETransientVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.1.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component not loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (!obj.p) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.1.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component already unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.1.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded 2')
+
+        success = true
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.2.qml b/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.2.qml
new file mode 100644
index 0000000000..120d249bc0
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/testVMETransientVMEComponent.2.qml
@@ -0,0 +1,45 @@
+import QtQuick 2.0
+
+Item {
+    property bool success: false
+
+    function reportError(s) { console.warn(s) }
+
+    Component.onCompleted: {
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.2.qml')) return reportError('Test component not loaded')
+        if (componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component already loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var comp = Qt.createComponent('VMETransientVMEComponent.qml')
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.2.qml')) return reportError('Test component not loaded 2')
+        if (!componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component not loaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already loaded')
+
+        var obj = comp.createObject()
+        if (!obj) return reportError('Invalid object')
+        if (obj.x == undefined) return reportError('Invalid object 2')
+        if (!obj.p) return reportError('Invalid object 3')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 4')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not loaded')
+
+        comp.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.2.qml')) return reportError('Test component not loaded 3')
+        if (!componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component already unloaded')
+        if (!componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component already unloaded')
+        if (!obj) return reportError('Invalid object 5')
+        if (obj.x == undefined) return reportError('Invalid object 6')
+        if (!obj.p) return reportError('Invalid object 7')
+        if (obj.p.foo != 'bar') return reportError('Invalid object 8')
+
+        obj.destroy()
+        componentCache.trim()
+        if (!componentCache.isTypeLoaded('testVMETransientVMEComponent.2.qml')) return reportError('Test component not loaded 4')
+        if (componentCache.isTypeLoaded('VMETransientVMEComponent.qml')) return reportError('Transient component not unloaded')
+        if (componentCache.isTypeLoaded('VMEComponent.qml')) return reportError('VME component not unloaded')
+
+        success = true
+    }
+}