CppEditor: Properly handle function types as template arguments

... when creating getters and setters.

Fixes: QTCREATORBUG-27133
Change-Id: Ia77147a270fb1229c765ff9d5f03aa243d51fe97
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/libs/cplusplus/NamePrettyPrinter.cpp

@@ -84,10 +84,13 @@ void NamePrettyPrinter::visit(const TemplateNameId *name)
 
         TemplateArgument templArg = name->templateArgumentAt(index);
         QString arg;
-        if (templArg.type().isValid())
+        if (templArg.type().isValid()) {
-            arg = overview()->prettyType(templArg.type());
+            Overview o = *_overview;
-        else if (const NumericLiteral *num = templArg.numericLiteral())
+            o.showReturnTypes = true;
+            arg = o.prettyType(templArg.type());
+        } else if (const NumericLiteral *num = templArg.numericLiteral()) {
             arg = QString::fromLatin1(num->chars(), num->size());
+        }
 
         if (arg.isEmpty())
             _name += QString::fromLatin1("_Tp%1").arg(index + 1);

src/plugins/cppeditor/cppquickfix_test.cpp

@@ -3362,6 +3362,43 @@ void QuickfixTest::testGenerateGetterSetterOnlySetterHeaderFileWithIncludeGuard(
     QuickFixOperationTest(testDocuments, &factory, ProjectExplorer::HeaderPaths(), 0);
 }
 
+void QuickfixTest::testGenerateGetterFunctionAsTemplateArg()
+{
+    QList<TestDocumentPtr> testDocuments;
+    const QByteArray original = R"(
+template<typename T> class TS {};
+template<typename T, typename U> class TS<T(U)> {};
+
+class S2 {
+    TS<int(int)> @member;
+};
+)";
+    const QByteArray expected = R"(
+template<typename T> class TS {};
+template<typename T, typename U> class TS<T(U)> {};
+
+class S2 {
+    TS<int(int)> member;
+
+public:
+    const TS<int (int)> &getMember() const
+    {
+        return member;
+    }
+};
+)";
+
+    testDocuments << CppTestDocument::create("file.h", original, expected);
+
+    QuickFixSettings s;
+    s->getterOutsideClassFrom = 0;
+    s->getterInCppFileFrom = 0;
+    s->getterNameTemplate = "get<Name>";
+
+    GenerateGetterSetter factory;
+    QuickFixOperationTest(testDocuments, &factory, ProjectExplorer::HeaderPaths(), 1);
+}
+
 class CppCodeStyleSettingsChanger {
 public:
     CppCodeStyleSettingsChanger(const CppCodeStyleSettings &settings);

src/plugins/cppeditor/cppquickfix_test.h

@@ -115,6 +115,7 @@ private slots:
     void testGenerateGetterSetterOnlySetter();
     void testGenerateGetterSetterInlineInHeaderFile();
     void testGenerateGetterSetterOnlySetterHeaderFileWithIncludeGuard();
+    void testGenerateGetterFunctionAsTemplateArg();
     void testGenerateGettersSetters_data();
     void testGenerateGettersSetters();