Merge pull request #4307 from fzarifian/fzarifian-pr4304

#4304 the stepwise plugin must be blocked on cacheprovider plugin block request

AUTHORS

@@ -76,6 +76,7 @@ Endre Galaczi
 Eric Hunsberger
 Eric Siegerman
 Erik M. Bray
+Fabien Zarifian
 Fabio Zadrozny
 Feng Ma
 Florian Bruhin

changelog/4304.bugfix.rst

@@ -0,0 +1 @@
+Block the ``stepwise`` plugin if ``cacheprovider`` is also blocked, as one depends on the other.

src/_pytest/config/__init__.py

@@ -477,6 +477,11 @@ class PytestPluginManager(PluginManager):
     def consider_pluginarg(self, arg):
         if arg.startswith("no:"):
             name = arg[3:]
+            # PR #4304 : remove stepwise if cacheprovider is blocked
+            if name == "cacheprovider":
+                self.set_blocked("stepwise")
+                self.set_blocked("pytest_stepwise")
+
             self.set_blocked(name)
             if not name.startswith("pytest_"):
                 self.set_blocked("pytest_" + name)

testing/test_pluginmanager.py

@@ -380,3 +380,21 @@ class TestPytestPluginManagerBootstrapming(object):
         pytestpm.consider_preparse(["xyz", "-p", "no:abc"])
         l2 = pytestpm.get_plugins()
         assert 42 not in l2
+
+    def test_plugin_prevent_register_stepwise_on_cacheprovider_unregister(
+        self, pytestpm
+    ):
+        """ From PR #4304 : The only way to unregister a module is documented at
+        the end of https://docs.pytest.org/en/latest/plugins.html.
+
+        When unregister cacheprovider, then unregister stepwise too
+        """
+        pytestpm.register(42, name="cacheprovider")
+        pytestpm.register(43, name="stepwise")
+        l1 = pytestpm.get_plugins()
+        assert 42 in l1
+        assert 43 in l1
+        pytestpm.consider_preparse(["xyz", "-p", "no:cacheprovider"])
+        l2 = pytestpm.get_plugins()
+        assert 42 not in l2
+        assert 43 not in l2