Tests: get rid of classes in test files.

Class usage came from the unittest framework and it was always redundant
after migration to the pytest.  This commit removes classes from files
containing tests to make them more readable and understandable.

test/test_java_isolation_rootfs.py

@@ -2,64 +2,65 @@ import os
 import subprocess
 
 import pytest
-from unit.applications.lang.java import TestApplicationJava
+from unit.applications.lang.java import ApplicationJava
 from unit.option import option
 
 prerequisites = {'modules': {'java': 'all'}, 'privileged_user': True}
 
+client = ApplicationJava()
 
-class TestJavaIsolationRootfs(TestApplicationJava):
-    @pytest.fixture(autouse=True)
-    def setup_method_fixture(self, temp_dir):
-        os.makedirs(f'{temp_dir}/jars')
-        os.makedirs(f'{temp_dir}/tmp')
-        os.chmod(f'{temp_dir}/tmp', 0o777)
 
-        try:
-            subprocess.run(
-                [
-                    "mount",
-                    "--bind",
-                    f'{option.current_dir}/build',
-                    f'{temp_dir}/jars',
-                ],
-                stderr=subprocess.STDOUT,
-            )
+@pytest.fixture(autouse=True)
+def setup_method_fixture(temp_dir):
+    os.makedirs(f'{temp_dir}/jars')
+    os.makedirs(f'{temp_dir}/tmp')
+    os.chmod(f'{temp_dir}/tmp', 0o777)
 
-        except KeyboardInterrupt:
-            raise
-
-        except subprocess.CalledProcessError:
-            pytest.fail("Can't run mount process.")
-
-    def teardown_method(self):
-        try:
-            subprocess.run(
-                ["umount", "--lazy", f"{option.temp_dir}/jars"],
-                stderr=subprocess.STDOUT,
-            )
-
-        except KeyboardInterrupt:
-            raise
-
-        except subprocess.CalledProcessError:
-            pytest.fail("Can't run umount process.")
-
-    def test_java_isolation_rootfs_chroot_war(self, temp_dir):
-        isolation = {'rootfs': temp_dir}
-
-        self.load('empty_war', isolation=isolation)
-
-        assert 'success' in self.conf(
-            '"/"',
-            '/config/applications/empty_war/working_directory',
+    try:
+        subprocess.run(
+            [
+                "mount",
+                "--bind",
+                f'{option.current_dir}/build',
+                f'{temp_dir}/jars',
+            ],
+            stderr=subprocess.STDOUT,
         )
 
-        assert 'success' in self.conf(
-            '"/jars"', 'applications/empty_war/unit_jars'
-        )
-        assert 'success' in self.conf(
-            '"/java/empty.war"', 'applications/empty_war/webapp'
+    except KeyboardInterrupt:
+        raise
+
+    except subprocess.CalledProcessError:
+        pytest.fail("Can't run mount process.")
+
+    yield
+
+    try:
+        subprocess.run(
+            ["umount", "--lazy", f"{option.temp_dir}/jars"],
+            stderr=subprocess.STDOUT,
         )
 
-        assert self.get()['status'] == 200, 'war'
+    except KeyboardInterrupt:
+        raise
+
+    except subprocess.CalledProcessError:
+        pytest.fail("Can't run umount process.")
+
+
+def test_java_isolation_rootfs_chroot_war(temp_dir):
+    client.load('empty_war', isolation={'rootfs': temp_dir})
+
+    assert 'success' in client.conf(
+        '"/"',
+        '/config/applications/empty_war/working_directory',
+    )
+
+    assert 'success' in client.conf(
+        '"/jars"', 'applications/empty_war/unit_jars'
+    )
+    assert 'success' in client.conf(
+        '"/java/empty.war"', 'applications/empty_war/webapp'
+    )
+
+    assert client.get()['status'] == 200, 'war'