Remove array function warning on first creation

5 files changed, 6 insertions, 41 deletions

diff --git a/CHANGES b/CHANGES
index a4f5f4a..933afc4 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,9 @@ Pint Changelog
 0.11 (unreleased)
 -----------------
 
+- Quantities wrapping NumPy arrays will no longer warning for the changed
+  array function behavior introduced in 0.10.
+  (Issue #1029, Thanks Jon Thielen)
 - **BREAKING CHANGE**:
   The array protocol fallback deprecated in version 0.10 has been removed.
   (Issue #1029, Thanks Jon Thielen)
diff --git a/pint/compat.py b/pint/compat.py
index e6037b2..e8e1a1b 100644
--- a/pint/compat.py
+++ b/pint/compat.py
@@ -36,27 +36,6 @@ class BehaviorChangeWarning(UserWarning):
     pass
 
 
-array_function_change_msg = """The way Pint handles NumPy operations has changed with the
-implementation of NEP 18. Unimplemented NumPy operations will now fail instead of making
-assumptions about units. Some functions, eg concat, will now return Quanties with units, where
-they returned ndarrays previously. See https://github.com/hgrecco/pint/pull/905.
-
-To hide this warning, wrap your first creation of an array Quantity with
-warnings.catch_warnings(), like the following:
-
-import numpy as np
-import warnings
-from pint import Quantity
-
-with warnings.catch_warnings():
-    warnings.simplefilter("ignore")
-    Quantity([])
-
-To disable the new behavior, see
-https://www.numpy.org/neps/nep-0018-array-function-protocol.html#implementation
-"""
-
-
 try:
     import numpy as np
     from numpy import ndarray
@@ -92,7 +71,6 @@ try:
             return False
 
     HAS_NUMPY_ARRAY_FUNCTION = _test_array_function_protocol()
-    SKIP_ARRAY_FUNCTION_CHANGE_WARNING = not HAS_NUMPY_ARRAY_FUNCTION
 
     NP_NO_VALUE = np._NoValue
 
@@ -107,7 +85,6 @@ except ImportError:
     NUMPY_VER = "0"
     NUMERIC_TYPES = (Number, Decimal)
     HAS_NUMPY_ARRAY_FUNCTION = False
-    SKIP_ARRAY_FUNCTION_CHANGE_WARNING = True
     NP_NO_VALUE = None
 
     def _to_magnitude(value, force_ndarray=False, force_ndarray_like=False):
diff --git a/pint/quantity.py b/pint/quantity.py
index 59b97d2..91eee2a 100644
--- a/pint/quantity.py
+++ b/pint/quantity.py
@@ -20,12 +20,9 @@ import warnings
 
 from pkg_resources.extern.packaging import version
 
-from .compat import SKIP_ARRAY_FUNCTION_CHANGE_WARNING  # noqa: F401
 from .compat import (
     NUMPY_VER,
-    BehaviorChangeWarning,
     _to_magnitude,
-    array_function_change_msg,
     babel_parse,
     eq,
     is_duck_array_type,
@@ -160,8 +157,6 @@ class Quantity(PrettyIPython, SharedRegistryObject):
         return _unpickle, (Quantity, self.magnitude, self._units)
 
     def __new__(cls, value, units=None):
-        global SKIP_ARRAY_FUNCTION_CHANGE_WARNING
-
         if is_upcast_type(type(value)):
             raise TypeError(f"Quantity cannot wrap upcast type {type(value)}")
         elif units is None:
@@ -214,12 +209,6 @@ class Quantity(PrettyIPython, SharedRegistryObject):
         inst.__used = False
         inst.__handling = None
 
-        if not SKIP_ARRAY_FUNCTION_CHANGE_WARNING and isinstance(
-            inst._magnitude, ndarray
-        ):
-            warnings.warn(array_function_change_msg, BehaviorChangeWarning)
-            SKIP_ARRAY_FUNCTION_CHANGE_WARNING = True
-
         return inst
 
     @property
diff --git a/pint/testsuite/test_numpy.py b/pint/testsuite/test_numpy.py
index 05aea96..3eeab6c 100644
--- a/pint/testsuite/test_numpy.py
+++ b/pint/testsuite/test_numpy.py
@@ -1,7 +1,6 @@
 import copy
 import operator as op
 import unittest
-from unittest.mock import patch
 
 from pint import DimensionalityError, OffsetUnitCalculusError, UnitStrippedWarning
 from pint.compat import np
diff --git a/pint/testsuite/test_quantity.py b/pint/testsuite/test_quantity.py
index fbfd773..51faf1a 100644
--- a/pint/testsuite/test_quantity.py
+++ b/pint/testsuite/test_quantity.py
@@ -6,7 +6,7 @@ import warnings
 from unittest.mock import patch
 
 from pint import DimensionalityError, OffsetUnitCalculusError, UnitRegistry
-from pint.compat import BehaviorChangeWarning, np
+from pint.compat import np
 from pint.testsuite import QuantityTestCase, helpers
 from pint.testsuite.parameterized import ParameterizedTestCase
 from pint.unit import UnitsContainer
@@ -531,11 +531,8 @@ class TestQuantity(QuantityTestCase):
             iter(x)
 
     @helpers.requires_array_function_protocol()
-    @patch("pint.quantity.SKIP_ARRAY_FUNCTION_CHANGE_WARNING", False)
-    def test_array_function_warning_on_creation(self):
-        # Test that warning is raised on first creation, but not second
-        with self.assertWarns(BehaviorChangeWarning):
-            self.Q_([])
+    def test_no_longer_array_function_warning_on_creation(self):
+        # Test that warning is no longer raised on first creation
         with warnings.catch_warnings():
             warnings.filterwarnings("error")
             self.Q_([])