diff --git a/autotests/syntaxrepository_test.cpp b/autotests/syntaxrepository_test.cpp
--- a/autotests/syntaxrepository_test.cpp
+++ b/autotests/syntaxrepository_test.cpp
@@ -222,6 +222,33 @@
         QCOMPARE(definitionNames, expectedDefinitionNames);
     }
 
+    void testIncludedFormats()
+    {
+        QStringList definitionNames;
+        foreach (const auto &def, m_repo.definitions()) {
+            definitionNames.push_back(def.name());
+        }
+
+        foreach (const QString & name, definitionNames) {
+            Repository repo;
+            auto def = repo.definitionForName(name);
+            auto includedDefs = def.includedDefinitions();
+            includedDefs.push_front(def);
+            QVector<int> formatIds;
+            for (auto d : qAsConst(includedDefs)) {
+                const auto formats = d.formats();
+                for (const auto format : formats)
+                    formatIds.push_back(format.id());
+            }
+            std::sort(formatIds.begin(), formatIds.end());
+            QVector<int> expectedIds((int)formatIds.size());
+            std::iota(expectedIds.begin(), expectedIds.end(), 1);
+            qDebug() << formatIds << name;
+            qDebug() << expectedIds;
+            QCOMPARE(formatIds, expectedIds);
+        }
+    }
+
     void testReload()
     {
         auto def = m_repo.definitionForName(QLatin1String("QML"));