diff --git a/include/pybind11/attr.h b/include/pybind11/attr.h
index aed6ba615..d6fc5405d 100644
--- a/include/pybind11/attr.h
+++ b/include/pybind11/attr.h
@@ -82,14 +82,14 @@ struct base {
     .. note:: This is an advanced feature. If you use this, you likely need
               to implement polymorphic_type_hook for your type hierarchy.
  \endrst */
-template <typename T> struct custom_base {
-    using caster = void *(*)(void *);
+template <typename T>
+struct custom_base {
+    using caster = void *(*) (void *);
 
     explicit custom_base(const caster &f) : fn(f) {}
     caster fn;
 };
 
-
 /// Keep patient alive while nurse lives
 template <size_t Nurse, size_t Patient>
 struct keep_alive {};
@@ -579,8 +579,7 @@ struct process_attribute<base<T>> : process_attribute_default<base<T>> {
 /// Process a custom base attribute
 template <typename T>
 struct process_attribute<custom_base<T>> : process_attribute_default<custom_base<T>> {
-    static void init(const custom_base<T> &b, type_record *r)
-    {
+    static void init(const custom_base<T> &b, type_record *r) {
         r->add_base(typeid(T), b.fn);
         // TODO: rename this to 'nonsimple'?
         r->multiple_inheritance = true;
diff --git a/tests/test_custom_base.cpp b/tests/test_custom_base.cpp
index dc0ec1f63..411b11682 100644
--- a/tests/test_custom_base.cpp
+++ b/tests/test_custom_base.cpp
@@ -28,7 +28,8 @@ TEST_SUBMODULE(custom_base, m) {
 
     py::class_<Derived>(m, "Derived", py::custom_base<Base>([](void *o) -> void * {
                             return &reinterpret_cast<Derived *>(o)->base;
-                        })).def_readwrite("j", &Derived::j);
+                        }))
+        .def_readwrite("j", &Derived::j);
 
     m.def("create_derived", []() { return new Derived; });
     m.def("create_base", []() { return new Base; });
@@ -36,4 +37,4 @@ TEST_SUBMODULE(custom_base, m) {
     m.def("base_i", [](Base *b) { return b->i; });
 
     m.def("derived_j", [](Derived *d) { return d->j; });
-};
\ No newline at end of file
+};