Treat substitution free template string literals as string bindings

Before this change, they were treated as script bindings, which are less
efficient, and could not be used in ListElement.

Fixes: QTBUG-95139
Pick-to: 6.2
Change-Id: Ic66052c7f58b3ffdf1b7c0c169f42b4f99df62a1
Reviewed-by: Maximilian Goldstein <max.goldstein@qt.io>
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

5 files changed, 32 insertions, 5 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index c623fcfd6e..e213f5dbe9 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -1125,6 +1125,12 @@ void IRBuilder::setBindingValue(QV4::CompiledData::Binding *binding, QQmlJS::AST
         if (QQmlJS::AST::StringLiteral *lit = QQmlJS::AST::cast<QQmlJS::AST::StringLiteral *>(expr)) {
             binding->type = QV4::CompiledData::Binding::Type_String;
             binding->stringIndex = registerString(lit->value.toString());
+        } else if (QQmlJS::AST::TemplateLiteral *templateLit = QQmlJS::AST::cast<QQmlJS::AST::TemplateLiteral *>(expr);
+                   templateLit && templateLit->hasNoSubstitution) {
+            // A template literal without substitution is just a string.
+            // With substitution, it could however be an arbitrarily complex expression
+            binding->type = QV4::CompiledData::Binding::Type_String;
+            binding->stringIndex = registerString(templateLit->value.toString());
         } else if (expr->kind == QQmlJS::AST::Node::Kind_TrueLiteral) {
             binding->type = QV4::CompiledData::Binding::Type_Boolean;
             binding->value.b = true;
diff --git a/src/qml/parser/qqmljs.g b/src/qml/parser/qqmljs.g
index eb082b77c2..670564fea5 100644
--- a/src/qml/parser/qqmljs.g
+++ b/src/qml/parser/qqmljs.g
@@ -2246,7 +2246,14 @@ InitializerOpt: Initializer;
 InitializerOpt_In: Initializer_In;
 
 TemplateLiteral: T_NO_SUBSTITUTION_TEMPLATE;
-/.  case $rule_number: Q_FALLTHROUGH(); ./
+/.
+    case $rule_number: {
+        AST::TemplateLiteral *node = new (pool) AST::TemplateLiteral(stringRef(1), rawStringRef(1), nullptr);
+        node->literalToken = loc(1);
+        node->hasNoSubstitution = true;
+        sym(1).Node = node;
+    } break;
+./
 
 TemplateSpans: T_TEMPLATE_TAIL;
 /.
diff --git a/src/qml/parser/qqmljsast_p.h b/src/qml/parser/qqmljsast_p.h
index d7b4f2a8be..bd4e225412 100644
--- a/src/qml/parser/qqmljsast_p.h
+++ b/src/qml/parser/qqmljsast_p.h
@@ -735,6 +735,7 @@ public:
 
     void accept0(BaseVisitor *visitor) override;
 
+    bool hasNoSubstitution = false;
     QStringView value;
     QStringView rawValue;
     ExpressionNode *expression;
diff --git a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
index 150fb82ca6..a9b6ec03a4 100644
--- a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
+++ b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
@@ -135,6 +135,7 @@ private slots:
     void objectDestroyed();
     void destroyObject();
     void emptyStringNotUndefined();
+    void listElementWithTemplateString();
 };
 
 bool tst_qqmllistmodel::compareVariantList(const QVariantList &testList, QVariant object)
@@ -1839,6 +1840,22 @@ void tst_qqmllistmodel::emptyStringNotUndefined()
     QCOMPARE(val.toString(), QString());
 }
 
+void tst_qqmllistmodel::listElementWithTemplateString()
+{
+    QQmlEngine engine;
+    QQmlComponent component(&engine);
+    component.setData(R"(
+    import QtQuick
+    ListModel {
+        ListElement {
+            prop: `test`
+        }
+    })", QUrl());
+    QVERIFY2(component.isReady(), qPrintable(component.errorString()));
+    QScopedPointer<QObject> root(component.create());
+    QVERIFY(!root.isNull());
+}
+
 QTEST_MAIN(tst_qqmllistmodel)
 
 #include "tst_qqmllistmodel.moc"
diff --git a/tests/auto/quick/examples/BLACKLIST b/tests/auto/quick/examples/BLACKLIST
index 14abb3099a..a4e374347e 100644
--- a/tests/auto/quick/examples/BLACKLIST
+++ b/tests/auto/quick/examples/BLACKLIST
@@ -1,7 +1,3 @@
-# QTBUG-95139
-[sgexamples:examples/quick/views/listview/expandingdelegates.qml]
-*
-
 # The following rely on qtquickcontrols2, and can be unblacklisted once QTBUG-95173 is done.
 [sgexamples:examples/quick/canvas/bezierCurve/bezierCurve.qml]
 *