call pkg_patcher only when it's needed

Author: xrmx

opentelemetry-instrumentation/tests/test_bootstrap.py

@@ -63,13 +63,11 @@ def setUp(self):
         super().setUp()
         self.mock_pip_check = self.pip_check_patcher.start()
         self.mock_pip_install = self.pip_install_patcher.start()
-        self.pkg_patcher.start()
 
     def tearDown(self):
         super().tearDown()
         self.pip_check_patcher.stop()
         self.pip_install_patcher.stop()
-        self.pkg_patcher.stop()
 
     @patch("sys.argv", ["bootstrap", "-a", "pipenv"])
     def test_run_unknown_cmd(self):
@@ -78,25 +76,28 @@ def test_run_unknown_cmd(self):
 
     @patch("sys.argv", ["bootstrap", "-a", "requirements"])
     def test_run_cmd_print(self):
+        self.pkg_patcher.start()
         with patch("sys.stdout", new=StringIO()) as fake_out:
             bootstrap.run()
             self.assertEqual(
                 fake_out.getvalue(),
                 "\n".join(self.installed_libraries) + "\n",
             )
+        self.pkg_patcher.stop()
 
     @patch("sys.argv", ["bootstrap", "-a", "install"])
     def test_run_cmd_install(self):
+        self.pkg_patcher.start()
         bootstrap.run()
         self.mock_pip_install.assert_has_calls(
             [call(i) for i in self.installed_libraries],
             any_order=True,
         )
         self.mock_pip_check.assert_called_once()
+        self.pkg_patcher.stop()
 
     @patch("sys.argv", ["bootstrap", "-a", "install"])
     def test_can_override_available_libraries(self):
-        self.pkg_patcher.stop()
         bootstrap.run(libraries=[])
         self.mock_pip_install.assert_has_calls(
             [call(i) for i in default_instrumentations],
@@ -106,7 +107,6 @@ def test_can_override_available_libraries(self):
 
     @patch("sys.argv", ["bootstrap", "-a", "install"])
     def test_can_override_available_default_instrumentations(self):
-        self.pkg_patcher.stop()
         with patch(
             "opentelemetry.instrumentation.bootstrap._is_installed",
             return_value=True,