remove redundant tests (#3650)

lib/iris/tests/unit/analysis/__init__.py

@@ -4,42 +4,3 @@
 # See COPYING and COPYING.LESSER in the root of the repository for full
 # licensing details.
 """Unit tests for the :mod:`iris.analysis` package."""
-
-# Import iris.tests first so that some things can be initialised before
-# importing anything else.
-import iris.tests as tests
-
-from unittest import mock
-
-from iris.analysis import Linear
-
-
-class Test_Linear(tests.IrisTest):
-    def setUp(self):
-        self.extrap = "some extrapolation"
-
-    def test___init__(self):
-        linear = Linear(extrapolation_mode=self.extrap)
-        self.assertEqual(
-            getattr(linear, "extrapolation_mode", None), self.extrap
-        )
-
-    @mock.patch("iris.analysis.LinearInterpolator", name="LinearInterpolator")
-    def test_interpolator(self, linear_interp_patch):
-        mock_interpolator = mock.Mock(name="mocked linear interpolator")
-        linear_interp_patch.return_value = mock_interpolator
-
-        linear = Linear(self.extrap)
-        cube = mock.Mock(name="cube")
-        coords = mock.Mock(name="coords")
-
-        interpolator = linear.interpolator(cube, coords)
-
-        self.assertIs(interpolator, mock_interpolator)
-        linear_interp_patch.assert_called_once_with(
-            cube, coords, extrapolation_mode=self.extrap
-        )
-
-
-if __name__ == "__main__":
-    tests.main()