QQmlJSTypePropagator: Support StoreNameStrict

As far as the type propagator is concerned, it is the the same as
StoreNameSloppy. This allows the unqualified id check to work in strict
functions, too.

Change-Id: Ie4ca823c996e058e4cdde632acaa1caa146b77bc
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
(cherry picked from commit f9d74e8326b11b39b3bdbcb1ff87a9c8f8bc0d34)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

4 files changed, 34 insertions, 4 deletions

diff --git a/src/qmlcompiler/qqmljstypepropagator.cpp b/src/qmlcompiler/qqmljstypepropagator.cpp
index 4ea5cedd1f..a61a6e5743 100644
--- a/src/qmlcompiler/qqmljstypepropagator.cpp
+++ b/src/qmlcompiler/qqmljstypepropagator.cpp
@@ -577,7 +577,18 @@ void QQmlJSTypePropagator::generate_LoadQmlContextPropertyLookup(int index)
         m_attachedContext = QQmlJSScope::ConstPtr();
 }
 
-void QQmlJSTypePropagator::generate_StoreNameSloppy(int nameIndex)
+/*!
+    \internal
+    As far as type propagation is involved, StoreNameSloppy and
+    StoreNameStrict are completely the same
+    StoreNameStrict is rejecting a few writes (where the variable was not
+    defined before) that would work in a sloppy context in JS, but the
+    compiler would always reject this. And for type propagation, this does
+    not matter at all.
+    \a nameIndex is the index in the string table corresponding to
+    the name which we are storing
+ */
+void QQmlJSTypePropagator::generate_StoreNameCommon(int nameIndex)
 {
     const QString name = m_jsUnitGenerator->stringForIndex(nameIndex);
     const QQmlJSRegisterContent type = m_typeResolver->scopedType(m_function->qmlScope, name);
@@ -634,11 +645,14 @@ void QQmlJSTypePropagator::generate_StoreNameSloppy(int nameIndex)
     }
 }
 
+void QQmlJSTypePropagator::generate_StoreNameSloppy(int nameIndex)
+{
+    return generate_StoreNameCommon(nameIndex);
+}
+
 void QQmlJSTypePropagator::generate_StoreNameStrict(int name)
 {
-    m_state.setHasSideEffects(true);
-    Q_UNUSED(name)
-    INSTR_PROLOGUE_NOT_IMPLEMENTED();
+    return generate_StoreNameCommon(name);
 }
 
 bool QQmlJSTypePropagator::checkForEnumProblems(
diff --git a/src/qmlcompiler/qqmljstypepropagator_p.h b/src/qmlcompiler/qqmljstypepropagator_p.h
index be72d03d94..0360671535 100644
--- a/src/qmlcompiler/qqmljstypepropagator_p.h
+++ b/src/qmlcompiler/qqmljstypepropagator_p.h
@@ -56,6 +56,7 @@ struct Q_QMLCOMPILER_PRIVATE_EXPORT QQmlJSTypePropagator : public QQmlJSCompileP
     void generate_LoadName(int nameIndex) override;
     void generate_LoadGlobalLookup(int index) override;
     void generate_LoadQmlContextPropertyLookup(int index) override;
+    void generate_StoreNameCommon(int nameIndex);
     void generate_StoreNameSloppy(int nameIndex) override;
     void generate_StoreNameStrict(int name) override;
     void generate_LoadElement(int base) override;
diff --git a/tests/auto/qml/qmllint/data/UnqualifiedInStoreStrict.qml b/tests/auto/qml/qmllint/data/UnqualifiedInStoreStrict.qml
new file mode 100644
index 0000000000..198e2146f5
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/UnqualifiedInStoreStrict.qml
@@ -0,0 +1,12 @@
+import QtQuick 2.15
+import QtQuick.Window 2.15
+
+Window {
+    Rectangle {
+        property real divisor: 0
+
+        Timer {
+            onTriggered: function() {"use strict"; divisor = 1 }
+        }
+    }
+}
diff --git a/tests/auto/qml/qmllint/tst_qmllint.cpp b/tests/auto/qml/qmllint/tst_qmllint.cpp
index 724d2d792d..daccda852a 100644
--- a/tests/auto/qml/qmllint/tst_qmllint.cpp
+++ b/tests/auto/qml/qmllint/tst_qmllint.cpp
@@ -266,6 +266,9 @@ void TestQmllint::testUnqualified_data()
     QTest::newRow("storeSloppy")
             << QStringLiteral("UnqualifiedInStoreSloppy.qml")
             << Result{ { Message{ QStringLiteral("Unqualified access"), 9, 26} } };
+    QTest::newRow("storeStrict")
+            << QStringLiteral("UnqualifiedInStoreStrict.qml")
+            << Result{ { Message{ QStringLiteral("Unqualified access"), 9, 52} } };
 }
 
 void TestQmllint::testUnknownCausesFail()