Add a few more dtype tests

example/example-numpy-dtypes.cpp

@@ -218,8 +218,14 @@ py::list test_dtype_ctors() {
     return list;
 }
 
-void test_dtype_methods() {
-
+py::list test_dtype_methods() {
+    py::list list;
+    auto dt1 = py::dtype::of<int32_t>();
+    auto dt2 = py::dtype::of<SimpleStruct>();
+    list.append(dt1); list.append(dt2);
+    list.append(py::bool_(dt1.has_fields())); list.append(py::bool_(dt2.has_fields()));
+    list.append(py::int_(dt1.itemsize())); list.append(py::int_(dt2.itemsize()));
+    return list;
 }
 
 void init_ex_numpy_dtypes(py::module &m) {

example/example-numpy-dtypes.py

@@ -7,7 +7,7 @@ from example import (
     create_rec_simple, create_rec_packed, create_rec_nested, print_format_descriptors,
     print_rec_simple, print_rec_packed, print_rec_nested, print_dtypes, get_format_unbound,
     create_rec_partial, create_rec_partial_nested, create_string_array, print_string_array,
-    test_array_ctors, test_dtype_ctors
+    test_array_ctors, test_dtype_ctors, test_dtype_methods
 )
 
 
@@ -92,3 +92,6 @@ d1 = np.dtype({'names': ['a', 'b'], 'formats': ['int32', 'float64'],
 d2 = np.dtype([('a', 'i4'), ('b', 'f4')])
 assert test_dtype_ctors() == [np.dtype('int32'), np.dtype('float64'),
                               np.dtype('bool'), d1, d1, np.dtype('uint32'), d2]
+
+assert test_dtype_methods() == [np.dtype('int32'), simple_dtype, False, True,
+                                np.dtype('int32').itemsize, simple_dtype.itemsize]