same for the units (although the magnitude format is ignored)

3 files changed, 24 insertions, 11 deletions

diff --git a/pint/testsuite/__init__.py b/pint/testsuite/__init__.py
index 35b6c89..8c0cd09 100644
--- a/pint/testsuite/__init__.py
+++ b/pint/testsuite/__init__.py
@@ -2,6 +2,8 @@ import doctest
 import math
 import os
 import unittest
+import warnings
+from contextlib import contextmanager
 
 from pint import UnitRegistry
 from pint.testsuite.helpers import PintOutputChecker
@@ -23,6 +25,14 @@ class QuantityTestCase:
         cls.U_ = None
 
 
+@contextmanager
+def assert_no_warnings():
+    with warnings.catch_warnings():
+        warnings.simplefilter("error")
+
+        yield
+
+
 def testsuite():
     """A testsuite that has all the pint tests."""
     suite = unittest.TestLoader().discover(os.path.dirname(__file__))
diff --git a/pint/testsuite/test_quantity.py b/pint/testsuite/test_quantity.py
index b3bb8e7..196d0c3 100644
--- a/pint/testsuite/test_quantity.py
+++ b/pint/testsuite/test_quantity.py
@@ -5,7 +5,6 @@ import math
 import operator as op
 import pickle
 import warnings
-from contextlib import contextmanager
 from unittest.mock import patch
 
 import pytest
@@ -18,18 +17,10 @@ from pint import (
     get_application_registry,
 )
 from pint.compat import np
-from pint.testsuite import QuantityTestCase, helpers
+from pint.testsuite import QuantityTestCase, assert_no_warnings, helpers
 from pint.unit import UnitsContainer
 
 
-@contextmanager
-def assert_no_warnings():
-    with warnings.catch_warnings():
-        warnings.simplefilter("error")
-
-        yield
-
-
 class FakeWrapper:
     # Used in test_upcast_type_rejection_on_creation
     def __init__(self, q):
diff --git a/pint/testsuite/test_unit.py b/pint/testsuite/test_unit.py
index 992551c..e6ce581 100644
--- a/pint/testsuite/test_unit.py
+++ b/pint/testsuite/test_unit.py
@@ -15,7 +15,7 @@ from pint import (
 )
 from pint.compat import np
 from pint.registry import LazyRegistry, UnitRegistry
-from pint.testsuite import QuantityTestCase, helpers
+from pint.testsuite import QuantityTestCase, assert_no_warnings, helpers
 from pint.util import ParserHelper, UnitsContainer
 
 
@@ -80,6 +80,18 @@ class TestUnit(QuantityTestCase):
                 ureg.default_format = spec
                 assert f"{x}" == result, f"Failed for {spec}, {result}"
 
+    def test_unit_formatting_defaults_warning(self):
+        ureg = UnitRegistry()
+        ureg.default_format = "~P"
+        x = ureg.Unit("m / s ** 2")
+
+        with pytest.warns(DeprecationWarning):
+            assert f"{x:.2f}" == "meter / second ** 2"
+
+        ureg.separate_format_defaults = True
+        with assert_no_warnings():
+            assert f"{x:.2f}" == "m/s²"
+
     def test_unit_formatting_snake_case(self, subtests):
         # Test that snake_case units are escaped where appropriate
         ureg = UnitRegistry()