Fix regression in array creation (#3353)

python/src/convert.cpp

@@ -491,7 +491,7 @@ mx::array create_array(nb::object v, std::optional<mx::Dtype> t) {
     std::optional<nb::dlpack::dtype> nb_dtype;
     // Nanobind does not recognize bfloat16 numpy array:
     // https://github.com/wjakob/nanobind/discussions/560
-    if (v.attr("dtype").equal(nb::str("bfloat16"))) {
+    if (nb::hasattr(v, "dtype") && v.attr("dtype").equal(nb::str("bfloat16"))) {
       nd = nb::cast<ContigArray>(v.attr("view")("uint16"));
       nb_dtype = nb::dtype<mx::bfloat16_t>();
     } else {

python/tests/test_array.py

@@ -1782,6 +1782,15 @@ class TestArray(mlx_tests.MLXTestCase):
         a_np = None
         self.assertIsNone(wr())
 
+    def test_create_from_buffer(self):
+        x = mx.array(b"Hello")
+        self.assertEqual(x.dtype, mx.uint8)
+        self.assertEqual(x.tolist(), [72, 101, 108, 108, 111])
+
+        x = mx.array(bytearray([1, 2, 3]))
+        self.assertEqual(x.dtype, mx.uint8)
+        self.assertEqual(x.tolist(), [1, 2, 3])
+
     @unittest.skipIf(not has_tf, "requires TensorFlow")
     def test_buffer_protocol_tf(self):
         dtypes_list = [