Drop entry-point distribution info when unregistering a plugin

changelog/763.bugfix.rst

@@ -0,0 +1 @@
+:meth:`PluginManager.unregister() <pluggy.PluginManager.unregister>` now also drops the plugin's entry from :meth:`~pluggy.PluginManager.list_plugin_distinfo` and :meth:`~pluggy.PluginManager.list_plugin_distributions`, so unloaded plugins no longer show up there and reloading them no longer adds duplicates.

src/pluggy/_manager.py

@@ -159,9 +159,7 @@ def __init__(self, project_name: str) -> None:
         #: The project name.
         self.project_name: Final = project_name
         self._name2plugin: Final[dict[str, _Plugin]] = {}
-        self._plugin_distinfo: Final[
-            list[tuple[_Plugin, importlib.metadata.Distribution]]
-        ] = []
+        self._name2dist: Final[dict[str, importlib.metadata.Distribution]] = {}
         #: The "hook relay", used to call a hook on all registered plugins.
         #: See :ref:`calling`.
         self.hook: Final = HookRelay()
@@ -313,9 +311,9 @@ def unregister(
             for hookcaller in hookcallers:
                 hookcaller._remove_plugin(plugin)
 
-        # if self._name2plugin[name] == None registration was blocked: ignore
-        if self._name2plugin.get(name) is not None:
-            del self._name2plugin[name]
+        if not self.is_blocked(name):
+            self._name2plugin.pop(name, None)
+        self._name2dist.pop(name, None)
 
         return plugin
 
@@ -517,7 +515,7 @@ def load_setuptools_entrypoints(self, group: str, name: str | None = None) -> in
                     continue
                 plugin = ep.load()
                 self.register(plugin, name=ep.name)
-                self._plugin_distinfo.append((plugin, dist))
+                self._name2dist[ep.name] = dist
                 count += 1
         return count
 
@@ -533,7 +531,10 @@ def list_plugin_distinfo(self) -> list[tuple[_Plugin, DistFacade]]:
         """
         from ._compat import DistFacade
 
-        return [(plugin, DistFacade(dist)) for plugin, dist in self._plugin_distinfo]
+        return [
+            (plugin, DistFacade(dist))
+            for plugin, dist in self.list_plugin_distributions()
+        ]
 
     def list_plugin_distributions(
         self,
@@ -543,7 +544,9 @@ def list_plugin_distributions(
 
         .. versionadded:: 1.7
         """
-        return list(self._plugin_distinfo)
+        return [
+            (self._name2plugin[name], dist) for name, dist in self._name2dist.items()
+        ]
 
     def list_name_plugin(self) -> list[tuple[str, _Plugin]]:
         """Return a list of (name, plugin) pairs for all registered plugins."""

testing/test_pluginmanager.py

@@ -488,6 +488,7 @@ class Plugin:
     # bloked plugins can be unregistred many times atm
     pm.unregister(p, "error")
     pm.unregister(p, "error")
+    assert pm.is_blocked("error")
 
 
 def test_register_unknown_hooks(pm: PluginManager) -> None:
@@ -939,6 +940,39 @@ def my_distributions():
     assert ret_distributions == [(plugin, dist)]
 
 
+def test_unregister_drops_plugin_distribution(
+    monkeypatch: pytest.MonkeyPatch, pm: PluginManager
+) -> None:
+    class EntryPoint:
+        group = "hello"
+
+        def __init__(self, name: str) -> None:
+            self.name = name
+
+        def load(self) -> object:
+            return type(self.name, (), {})()
+
+    class Distribution:
+        entry_points = (EntryPoint("a"), EntryPoint("b"))
+
+    dist = cast(importlib.metadata.Distribution, Distribution())
+    monkeypatch.setattr(importlib.metadata, "distributions", lambda: (dist,))
+
+    assert pm.load_setuptools_entrypoints("hello") == 2
+    b = pm.get_plugin("b")
+    pm.unregister(name="a")
+    assert pm.list_plugin_distributions() == [(b, dist)]
+    assert [p for p, _ in pm.list_plugin_distinfo()] == [b]
+
+    # reloading must not duplicate the remaining entry
+    assert pm.load_setuptools_entrypoints("hello") == 1
+    a = pm.get_plugin("a")
+    assert pm.list_plugin_distributions() == [(b, dist), (a, dist)]
+
+    pm.set_blocked("b")
+    assert pm.list_plugin_distributions() == [(a, dist)]
+
+
 def test_add_tracefuncs(he_pm: PluginManager) -> None:
     out: list[Any] = []