Remember QML document context in each qmltc-generated object

There is an apparent problem in certain cases where using outer context
to fetch ids is invalid: the outer context is the *outermost* context,
meaning that if a type has a derived type in another QML document,
the derived type would place its own context as a QQmlData::outerContext

As a simpler solution, just remember the document's context in all the
objects within this document. This automatically works in derived types
since they appear in other documents with separate contexts

Pick-to: 6.4
Fixes: QTBUG-103956
Change-Id: I29420ff4962b485502d87b2d2ac2f89b9e0f5736
Reviewed-by: Ulf Hermann <[email protected]>
Reviewed-by: Sami Shalayel <[email protected]>

8 files changed, 46 insertions, 11 deletions

diff --git a/tests/auto/qml/qmltc/QmltcTests/CMakeLists.txt b/tests/auto/qml/qmltc/QmltcTests/CMakeLists.txt
index 3093c978f1..f9877f29bc 100644
--- a/tests/auto/qml/qmltc/QmltcTests/CMakeLists.txt
+++ b/tests/auto/qml/qmltc/QmltcTests/CMakeLists.txt
@@ -32,6 +32,10 @@ set(qml_sources
     QmlTypeWithBaseTypeExtension.qml
     extensionTypeBindings.qml
 
+    qtbug103956/SubComponent.qml
+    qtbug103956/MainComponent.qml
+    qtbug103956/qtbug103956_main.qml
+
     signalHandlers.qml
     javaScriptFunctions.qml
     changingBindings.qml
diff --git a/tests/auto/qml/qmltc/QmltcTests/qtbug103956/MainComponent.qml b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/MainComponent.qml
new file mode 100644
index 0000000000..8518bc0919
--- /dev/null
+++ b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/MainComponent.qml
@@ -0,0 +1,9 @@
+import QtQuick
+import QmltcTests 1.0
+
+Item {
+    property alias firstComponent: firstComponent
+    SubComponent {
+        id: firstComponent
+    }
+}
diff --git a/tests/auto/qml/qmltc/QmltcTests/qtbug103956/SubComponent.qml b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/SubComponent.qml
new file mode 100644
index 0000000000..80ff9edf4e
--- /dev/null
+++ b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/SubComponent.qml
@@ -0,0 +1,5 @@
+import QtQuick
+
+Item {
+    property bool setMe: false
+}
diff --git a/tests/auto/qml/qmltc/QmltcTests/qtbug103956/qtbug103956_main.qml b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/qtbug103956_main.qml
new file mode 100644
index 0000000000..f8d1549c4b
--- /dev/null
+++ b/tests/auto/qml/qmltc/QmltcTests/qtbug103956/qtbug103956_main.qml
@@ -0,0 +1,9 @@
+import QmltcTests 1.0
+
+MainComponent {
+    firstComponent.setMe: true
+
+    MainComponent {
+        firstComponent.setMe: true
+    }
+}
diff --git a/tests/auto/qml/qmltc/tst_qmltc.cpp b/tests/auto/qml/qmltc/tst_qmltc.cpp
index 654ce91c3b..8536a01c20 100644
--- a/tests/auto/qml/qmltc/tst_qmltc.cpp
+++ b/tests/auto/qml/qmltc/tst_qmltc.cpp
@@ -47,6 +47,7 @@
 #include "gradients.h"
 #include "qjsvalueassignments.h"
 #include "extensiontypebindings.h"
+#include "qtbug103956_main.h"
 
 #include "signalhandlers.h"
 #include "javascriptfunctions.h"
@@ -837,6 +838,15 @@ void tst_qmltc::extensionTypeBindings()
     }
 }
 
+// QTBUG-103956
+void tst_qmltc::visibleAliasMethods()
+{
+    QQmlEngine e;
+    PREPEND_NAMESPACE(qtbug103956_main) created(&e);
+    QVERIFY(created.firstComponent());
+    QCOMPARE(created.firstComponent()->setMe(), true);
+}
+
 void tst_qmltc::signalHandlers()
 {
     QQmlEngine e;
diff --git a/tests/auto/qml/qmltc/tst_qmltc.h b/tests/auto/qml/qmltc/tst_qmltc.h
index a2678054db..94411ea29a 100644
--- a/tests/auto/qml/qmltc/tst_qmltc.h
+++ b/tests/auto/qml/qmltc/tst_qmltc.h
@@ -59,6 +59,7 @@ private slots:
     void gradients(); // QTBUG-102560
     void jsvalueAssignments();
     void extensionTypeBindings();
+    void visibleAliasMethods(); // QTBUG-103956
 
     void signalHandlers();
     void jsFunctions();
diff --git a/tools/qmltc/qmltccompiler.cpp b/tools/qmltc/qmltccompiler.cpp
index 7f4c6c0af4..a241cf0715 100644
--- a/tools/qmltc/qmltccompiler.cpp
+++ b/tools/qmltc/qmltccompiler.cpp
@@ -603,17 +603,9 @@ void QmltcCompiler::compileAlias(QmltcType &current, const QQmlJSMetaProperty &a
             Q_ASSERT(id >= 0); // since the type is found by id, it must have an id
 
             AliasResolutionFrame queryIdFrame {};
-            queryIdFrame.prologue << u"auto context = QQmlData::get(%1)->outerContext;"_s.arg(
-                    AliasResolutionFrame::inVar);
-            // there's a special case: when `this` type has compiled QML type as
-            // a base type and it is not a root, it has a non-root first
-            // context, so we need to step one level up
-            if (QQmlJSUtils::hasCompositeBase(owner) && owner != m_visitor->result()) {
-                Q_ASSERT(!owner->baseTypeName().isEmpty());
-                queryIdFrame.prologue
-                        << u"// `this` is special: not a root and its base type is compiled"_s;
-                queryIdFrame.prologue << u"context = context->parent().data();"_s;
-            }
+            Q_ASSERT(frames.top().outVar == u"this"_s); // so inVar would be "this" as well
+            queryIdFrame.prologue << u"auto context = %1::q_qmltc_thisContext;"_s.arg(
+                    owner->internalName());
 
             // doing the above allows us to lookup id object by index (fast)
             queryIdFrame.outVar = u"alias_objectById_" + aliasExprBits.front(); // unique enough
diff --git a/tools/qmltc/qmltccompilerpieces.h b/tools/qmltc/qmltccompilerpieces.h
index 545e347caf..6d4912f883 100644
--- a/tools/qmltc/qmltccompilerpieces.h
+++ b/tools/qmltc/qmltccompilerpieces.h
@@ -232,6 +232,11 @@ inline decltype(auto) QmltcCodeGenerator::generate_initCode(QmltcType &current,
             current.init.body << u"context->setContextObject(this);"_s;
     }
 
+    // context is this document's context. we must remember it in each type
+    current.variables.emplaceBack(u"QQmlRefPointer<QQmlContextData>"_s, u"q_qmltc_thisContext"_s,
+                                  u"nullptr"_s);
+    current.init.body << u"%1::q_qmltc_thisContext = context;"_s.arg(type->internalName());
+
     if (int id = visitor->runtimeId(type); id >= 0) {
         current.init.body << u"// 3. set id since it is provided"_s;
         QString idString = visitor->addressableScopes().id(type);