Make unit/config pytest

lib/iris/tests/unit/config/test_NetCDF.py

@@ -4,41 +4,40 @@
 # See LICENSE in the root of the repository for full licensing details.
 """Unit tests for the `iris.config.NetCDF` class."""
 
-# Import iris.tests first so that some things can be initialised before
-# importing anything else.
-import iris.tests as tests  # isort:skip
-
+import re
 import warnings
 
+import pytest
+
 import iris.config
 
 
-class Test(tests.IrisTest):
-    def setUp(self):
-        self.options = iris.config.NetCDF()
+@pytest.fixture
+def options():
+    return iris.config.NetCDF()
+
+
+def test_basic(options):
+    assert not options.conventions_override
 
-    def test_basic(self):
-        self.assertFalse(self.options.conventions_override)
 
-    def test_enabled(self):
-        self.options.conventions_override = True
-        self.assertTrue(self.options.conventions_override)
+def test_enabled(options):
+    options.conventions_override = True
+    assert options.conventions_override
 
-    def test_bad_value(self):
-        # A bad value should be ignored and replaced with the default value.
-        bad_value = "wibble"
-        with warnings.catch_warnings(record=True) as w:
-            warnings.simplefilter("always")
-            self.options.conventions_override = bad_value
-        self.assertFalse(self.options.conventions_override)
-        exp_wmsg = "Attempting to set invalid value {!r}".format(bad_value)
-        self.assertRegex(str(w[0].message), exp_wmsg)
 
-    def test__contextmgr(self):
-        with self.options.context(conventions_override=True):
-            self.assertTrue(self.options.conventions_override)
-        self.assertFalse(self.options.conventions_override)
+def test_bad_value(options):
+    # A bad value should be ignored and replaced with the default value.
+    bad_value = "wibble"
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+        options.conventions_override = bad_value
+    assert not options.conventions_override
+    exp_wmsg = "Attempting to set invalid value {!r}".format(bad_value)
+    assert re.match(exp_wmsg, str(w[0].message))
 
 
-if __name__ == "__main__":
-    tests.main()
+def test__contextmgr(options):
+    with options.context(conventions_override=True):
+        assert options.conventions_override
+    assert not options.conventions_override