Replace legacy np.string_ usage with np.bytes_

pyspectral/tests/test_utils.py

@@ -225,11 +225,11 @@ def test_get_wave_range(self):
 @pytest.mark.parametrize(
     ("input_value", "exp_except"),
     [
-        (np.string_("hey"), False),
-        (np.array([np.string_("hey")]), False),
-        (np.array(np.string_("hey")), False),
+        (np.bytes_("hey"), False),
+        (np.array([np.bytes_("hey")]), False),
+        (np.array(np.bytes_("hey")), False),
         ("hey", False),
-        (np.array([np.string_("hey"), np.string_("hey")]), True),
+        (np.array([np.bytes_("hey"), np.bytes_("hey")]), True),
         (5, True),
     ],
 )
@@ -247,8 +247,8 @@ def test_np2str(input_value, exp_except):
     [
         (b"Hello", "Hello"),
         ("Hello", "Hello"),
-        (np.string_("Hello"), "Hello"),
-        (np.array(np.string_("Hello")), np.array(np.string_("Hello"))),
+        (np.bytes_("Hello"), "Hello"),
+        (np.array(np.bytes_("Hello")), np.array(np.bytes_("Hello"))),
     ]
 )
 def test_bytes2string(input_value, exp_result):

pyspectral/utils.py

@@ -506,20 +506,23 @@ def convert2str(value):
 
 
 def np2str(value):
-    """Convert an `numpy.string_` to str.
+    """Convert an ``numpy.bytes_`` to str.
+
+    Note: ``numpy.string_`` was deprecated in numpy 2.0 in favor of
+    ``numpy.bytes_``.
 
     Args:
         value (ndarray): scalar or 1-element numpy array to convert
     Raises:
         ValueError: if value is array larger than 1-element or it is not of
-                    type `numpy.string_` or it is not a numpy array
+                    type `numpy.bytes_` or it is not a numpy array
 
     """
     if isinstance(value, str):
         return value
 
     if hasattr(value, 'dtype') and \
-            issubclass(value.dtype.type, (np.str_, np.string_, np.object_)) \
+            issubclass(value.dtype.type, (np.str_, np.bytes_, np.object_)) \
             and value.size == 1:
         value = value.item()
         # python 3 - was scalar numpy array of bytes