MAINT: Remove implicit inheritance from object class (#15236)

Inheriting from object was necessary for Python 2 compatibility to use
new-style classes. In Python 3, this is unnecessary as there are no
old-style classes.

Dropping the object is more idiomatic Python.

7 files changed, 21 insertions, 21 deletions

diff --git a/numpy/testing/_private/noseclasses.py b/numpy/testing/_private/noseclasses.py
index 7cad24620..493bacfdd 100644
--- a/numpy/testing/_private/noseclasses.py
+++ b/numpy/testing/_private/noseclasses.py
@@ -266,7 +266,7 @@ class NumpyDoctest(npd.Doctest):
         return npd.Doctest.wantFile(self, file)
 
 
-class Unplugger(object):
+class Unplugger:
     """ Nose plugin to remove named plugin late in loading
 
     By default it removes the "doctest" plugin.
diff --git a/numpy/testing/_private/nosetester.py b/numpy/testing/_private/nosetester.py
index 6226eeb3c..a874321cc 100644
--- a/numpy/testing/_private/nosetester.py
+++ b/numpy/testing/_private/nosetester.py
@@ -110,7 +110,7 @@ def run_module_suite(file_to_run=None, argv=None):
     nose.run(argv=argv, addplugins=[KnownFailurePlugin()])
 
 
-class NoseTester(object):
+class NoseTester:
     """
     Nose test runner.
 
diff --git a/numpy/testing/_private/parameterized.py b/numpy/testing/_private/parameterized.py
index 2134cca88..dbfb4807c 100644
--- a/numpy/testing/_private/parameterized.py
+++ b/numpy/testing/_private/parameterized.py
@@ -293,10 +293,10 @@ def detect_runner():
             _test_runner_guess = None
     return _test_runner_guess
 
-class parameterized(object):
+class parameterized:
     """ Parameterize a test case::
 
-            class TestInt(object):
+            class TestInt:
                 @parameterized([
                     ("A", 10),
                     ("F", 15),
diff --git a/numpy/testing/_private/utils.py b/numpy/testing/_private/utils.py
index 1e118b538..9e5a2eb2a 100644
--- a/numpy/testing/_private/utils.py
+++ b/numpy/testing/_private/utils.py
@@ -2001,7 +2001,7 @@ class clear_and_catch_warnings(warnings.catch_warnings):
                 mod.__warningregistry__.update(self._warnreg_copies[mod])
 
 
-class suppress_warnings(object):
+class suppress_warnings:
     """
     Context manager and decorator doing much the same as
     ``warnings.catch_warnings``.
diff --git a/numpy/testing/print_coercion_tables.py b/numpy/testing/print_coercion_tables.py
index c11b31968..84d46b59b 100755
--- a/numpy/testing/print_coercion_tables.py
+++ b/numpy/testing/print_coercion_tables.py
@@ -5,7 +5,7 @@
 import numpy as np
 
 # Generic object that can be added, but doesn't do anything else
-class GenericObject(object):
+class GenericObject:
     def __init__(self, v):
         self.v = v
 
diff --git a/numpy/testing/tests/test_decorators.py b/numpy/testing/tests/test_decorators.py
index fc8d764c2..77f8b66ba 100644
--- a/numpy/testing/tests/test_decorators.py
+++ b/numpy/testing/tests/test_decorators.py
@@ -21,7 +21,7 @@ else:
 
 
 @pytest.mark.skipif(not HAVE_NOSE, reason="Needs nose")
-class TestNoseDecorators(object):
+class TestNoseDecorators:
     # These tests are run in a class for simplicity while still
     # getting a report on each, skipped or success.
 
diff --git a/numpy/testing/tests/test_utils.py b/numpy/testing/tests/test_utils.py
index f752c63f3..232ca0e83 100644
--- a/numpy/testing/tests/test_utils.py
+++ b/numpy/testing/tests/test_utils.py
@@ -18,7 +18,7 @@ from numpy.testing import (
 from numpy.core.overrides import ARRAY_FUNCTION_ENABLED
 
 
-class _GenericTest(object):
+class _GenericTest:
 
     def _test_equal(self, a, b):
         self._assert_func(a, b)
@@ -209,7 +209,7 @@ class TestArrayEqual(_GenericTest):
         self._test_not_equal(b, a)
 
 
-class TestBuildErrorMessage(object):
+class TestBuildErrorMessage:
 
     def test_build_err_msg_defaults(self):
         x = np.array([1.00001, 2.00002, 3.00003])
@@ -616,7 +616,7 @@ class TestAlmostEqual(_GenericTest):
         self._assert_func(a, a)
 
 
-class TestApproxEqual(object):
+class TestApproxEqual:
 
     def setup(self):
         self._assert_func = assert_approx_equal
@@ -659,7 +659,7 @@ class TestApproxEqual(object):
         assert_raises(AssertionError, lambda: self._assert_func(ainf, anan))
 
 
-class TestArrayAssertLess(object):
+class TestArrayAssertLess:
 
     def setup(self):
         self._assert_func = assert_array_less
@@ -769,7 +769,7 @@ class TestArrayAssertLess(object):
 
 
 @pytest.mark.skip(reason="The raises decorator depends on Nose")
-class TestRaises(object):
+class TestRaises:
 
     def setup(self):
         class MyException(Exception):
@@ -803,7 +803,7 @@ class TestRaises(object):
             raise AssertionError("should have raised an AssertionError")
 
 
-class TestWarns(object):
+class TestWarns:
 
     def test_warn(self):
         def f():
@@ -854,7 +854,7 @@ class TestWarns(object):
             raise AssertionError("wrong warning caught by assert_warn")
 
 
-class TestAssertAllclose(object):
+class TestAssertAllclose:
 
     def test_simple(self):
         x = 1e-3
@@ -924,7 +924,7 @@ class TestAssertAllclose(object):
         assert_('Max relative difference: 0.5' in msg)
 
 
-class TestArrayAlmostEqualNulp(object):
+class TestArrayAlmostEqualNulp:
 
     def test_float64_pass(self):
         # The number of units of least precision
@@ -1121,7 +1121,7 @@ class TestArrayAlmostEqualNulp(object):
                       xi, y + y*1j, nulp)
 
 
-class TestULP(object):
+class TestULP:
 
     def test_equal(self):
         x = np.random.randn(10)
@@ -1177,7 +1177,7 @@ class TestULP(object):
                           maxulp=maxulp))
 
 
-class TestStringEqual(object):
+class TestStringEqual:
     def test_simple(self):
         assert_string_equal("hello", "hello")
         assert_string_equal("hello\nmultiline", "hello\nmultiline")
@@ -1239,7 +1239,7 @@ def test_warn_len_equal_call_scenarios():
     # check that no assertion is uncaught
 
     # parallel scenario -- no warning issued yet
-    class mod(object):
+    class mod:
         pass
 
     mod_inst = mod()
@@ -1249,7 +1249,7 @@ def test_warn_len_equal_call_scenarios():
 
     # serial test scenario -- the __warningregistry__
     # attribute should be present
-    class mod(object):
+    class mod:
         def __init__(self):
             self.__warningregistry__ = {'warning1':1,
                                         'warning2':2}
@@ -1524,7 +1524,7 @@ def test_clear_and_catch_warnings_inherit():
 
 
 @pytest.mark.skipif(not HAS_REFCOUNT, reason="Python lacks refcounts")
-class TestAssertNoGcCycles(object):
+class TestAssertNoGcCycles:
     """ Test assert_no_gc_cycles """
     def test_passes(self):
         def no_cycle():
@@ -1558,7 +1558,7 @@ class TestAssertNoGcCycles(object):
         error, instead of hanging forever trying to clear it.
         """
 
-        class ReferenceCycleInDel(object):
+        class ReferenceCycleInDel:
             """
             An object that not only contains a reference cycle, but creates new
             cycles whenever it's garbage-collected and its __del__ runs