Require existing typeinfo for direct conversions

This avoid a hashmap lookup since the pointer to the list of
direct converters is now cached in the typeinfo.

include/pybind11/cast.h

@@ -26,6 +26,7 @@ struct type_info {
     void (*init_holder)(PyObject *, const void *);
     std::vector<PyObject *(*)(PyObject *, PyTypeObject *)> implicit_conversions;
     std::vector<std::pair<const std::type_info *, void *(*)(void *)>> implicit_casts;
+    std::vector<bool (*)(PyObject *, void *&)> *direct_conversions;
     buffer_info *(*get_buffer)(PyObject *, void *) = nullptr;
     void *get_buffer_data = nullptr;
     /** A simple type never occurs as a (direct or indirect) parent
@@ -157,8 +158,7 @@ inline void keep_alive_impl(handle nurse, handle patient);
 class type_caster_generic {
 public:
     PYBIND11_NOINLINE type_caster_generic(const std::type_info &type_info)
-     : typeinfo(get_type_info(type_info, false)),
-       direct_conversions(get_internals().direct_conversions[std::type_index(type_info)]) { }
+     : typeinfo(get_type_info(type_info, false)) { }
 
     PYBIND11_NOINLINE bool load(handle src, bool convert) {
         if (!src)
@@ -167,14 +167,12 @@ public:
     }
 
     bool load(handle src, bool convert, PyTypeObject *tobj) {
-        if (!src)
+        if (!src || !typeinfo)
             return false;
         if (src.is_none()) {
             value = nullptr;
             return true;
         }
-        if (!typeinfo)
-            return load_direct(src, convert);
 
         if (typeinfo->simple_type) { /* Case 1: no multiple inheritance etc. involved */
             /* Check if we can safely perform a reinterpret-style cast */
@@ -218,9 +216,12 @@ public:
                 if (load(temp, false))
                     return true;
             }
+            for (auto &converter : *typeinfo->direct_conversions) {
+                if (converter(src.ptr(), value))
+                    return true;
+            }
         }
-
-        return load_direct(src, convert);
+        return false;
     }
 
     PYBIND11_NOINLINE static handle cast(const void *_src, return_value_policy policy, handle parent,
@@ -298,19 +299,8 @@ public:
 
 protected:
     const type_info *typeinfo = nullptr;
-    const std::vector<bool (*)(PyObject *, void *&)>& direct_conversions;
     void *value = nullptr;
     object temp;
-
-    bool load_direct(handle src, bool convert) {
-        if (convert) {
-            for (auto& converter : direct_conversions) {
-                if (converter(src.ptr(), value))
-                    return true;
-            }
-        }
-        return false;
-    }
 };
 
 /* Determine suitable casting operator */

include/pybind11/numpy.h

@@ -721,20 +721,21 @@ private:
     static std::string format_str;
     static PyObject* dtype_ptr;
 
-    static void register_direct_converter() {
-        auto converter = [=](PyObject *obj, void*& value) {
-            auto& api = npy_api::get();
-            if (!PyObject_TypeCheck(obj, api.PyVoidArrType_Type_))
-                return false;
-            if (auto descr = object(api.PyArray_DescrFromScalar_(obj), false)) {
-                if (api.PyArray_EquivTypes_(dtype_ptr, descr.ptr())) {
-                    value = ((PyVoidScalarObject_Proxy *) obj)->obval;
-                    return true;
-                }
-            }
+    static bool direct_converter(PyObject *obj, void*& value) {
+        auto& api = npy_api::get();
+        if (!PyObject_TypeCheck(obj, api.PyVoidArrType_Type_))
             return false;
-        };
-        get_internals().direct_conversions[std::type_index(typeid(T))].push_back(converter);
+        if (auto descr = object(api.PyArray_DescrFromScalar_(obj), false)) {
+            if (api.PyArray_EquivTypes_(dtype_ptr, descr.ptr())) {
+                value = ((PyVoidScalarObject_Proxy *) obj)->obval;
+                return true;
+            }
+        }
+        return false;
+    }
+
+    static void register_direct_converter() {
+        get_internals().direct_conversions[std::type_index(typeid(T))].push_back(direct_converter);
     }
 };
 

include/pybind11/pybind11.h

@@ -672,6 +672,7 @@ protected:
         tinfo->type = (PyTypeObject *) type;
         tinfo->type_size = rec->type_size;
         tinfo->init_holder = rec->init_holder;
+        tinfo->direct_conversions = &internals.direct_conversions[tindex];
         internals.registered_types_cpp[tindex] = tinfo;
         internals.registered_types_py[type] = tinfo;
 

tests/test_numpy_dtypes.cpp

@@ -309,11 +309,9 @@ test_initializer numpy_dtypes([](py::module &m) {
     PYBIND11_NUMPY_DTYPE(StringStruct, a, b);
     PYBIND11_NUMPY_DTYPE(EnumStruct, e1, e2);
 
-    // ... or after...
+    // ... or after
     py::class_<PackedStruct>(m, "PackedStruct");
 
-    // ... or not at all
-
     m.def("create_rec_simple", &create_recarray<SimpleStruct>);
     m.def("create_rec_packed", &create_recarray<PackedStruct>);
     m.def("create_rec_nested", &create_nested);

tests/test_numpy_dtypes.py

@@ -190,7 +190,7 @@ def test_scalar_conversion():
 
     for i, func in enumerate(funcs):
         for j, arr in enumerate(arrays):
-            if i == j:
+            if i == j and i < 2:
                 assert [func(arr[k]) for k in range(n)] == [k * 10 for k in range(n)]
             else:
                 with pytest.raises(TypeError) as excinfo: