More refactoring for plugin manager.

conda/plugins/manager.py

@@ -74,6 +74,24 @@
         else:
             return f"{prefix}.{plugin.__class__.__qualname__}[{id(plugin)}]"
 
+    def register(self, plugin, name: str | None = None) -> str | None:
+        """
+        Call :meth:`pluggy.PluginManager.register` and return the result or
+        ignore errors raised, except ``ValueError``, which means the plugin
+        had already been registered.
+        """
+        try:
+            # register plugin but ignore ValueError since that means
+            # the plugin has already been registered
+            return super().register(plugin, name=name)
+        except ValueError:
+            return None
+        except Exception as err:
+            raise PluginError(
+                f"Error while loading conda plugin: "
+                f"{name or self.get_canonical_name(plugin)} ({err})"
+            )
+
     def load_plugins(self, *plugins) -> int:
         """
         Load the provided list of plugins and fail gracefully on error.
@@ -82,18 +100,8 @@
         """
         count = 0
         for plugin in plugins:
-            try:
-                # register plugin
-                # extracts canonical name from plugin, checks for duplicates,
-                # and if blocked
-                if self.register(plugin):
-                    # successfully registered a plugin
-                    count += 1
-            except ValueError as err:
-                raise PluginError(
-                    f"Error while loading first-party conda plugin: "
-                    f"{self.get_canonical_name(plugin)} ({err})"
-                )
+            if self.register(plugin):
+                count += 1
         return count
 
     def load_entrypoints(self, group: str, name: str | None = None) -> int:
@@ -126,18 +134,8 @@
                     )
                     continue
 
-                try:
-                    # register plugin
-                    # extracts canonical name from plugin, checks for duplicates,
-                    # and if blocked
-                    if self.register(plugin):
-                        # successfully registered a plugin
-                        count += 1
-                except ValueError as err:
-                    raise PluginError(
-                        f"Error while loading third-party conda plugin: "
-                        f"{self.get_canonical_name(plugin)} ({err})"
-                    )
+                if self.register(plugin):
+                    count += 1
         return count
 
     @overload

tests/plugins/test_manager.py

@@ -57,18 +57,15 @@ def conda_virtual_packages(*args):
 
 
 def test_load_without_plugins(plugin_manager: CondaPluginManager):
-    plugin_names = plugin_manager.load_plugins()
-    assert plugin_names == 0
+    assert plugin_manager.load_plugins() == 0
 
 
 def test_load_two_plugins_one_impls(plugin_manager: CondaPluginManager):
-    plugin_names = plugin_manager.load_plugins(this_module)
-    assert plugin_names == 1
+    assert plugin_manager.load_plugins(this_module) == 1
     assert plugin_manager.get_plugins() == {this_module}
     assert plugin_manager.hook.conda_solvers.get_hookimpls() == []
 
-    plugin_names = plugin_manager.load_plugins(VerboseSolverPlugin)
-    assert plugin_names == 1
+    assert plugin_manager.load_plugins(VerboseSolverPlugin) == 1
     assert plugin_manager.get_plugins() == {this_module, VerboseSolverPlugin}
 
     hooks_impls = plugin_manager.hook.conda_solvers.get_hookimpls()
@@ -81,7 +78,7 @@ def test_get_hook_results(plugin_manager: CondaPluginManager):
     assert plugin_manager.get_hook_results(name) == []
 
     # loading the archspec plugin module and make sure it was loaded correctly
-    plugin_manager.load_plugins(virtual_packages.archspec)
+    assert plugin_manager.load_plugins(virtual_packages.archspec) == 1
     hook_result = plugin_manager.get_hook_results(name)
     assert len(hook_result) == 1
     assert hook_result[0].name == "archspec"
@@ -104,14 +101,7 @@ def conda_virtual_packages():
 
 
 def test_load_plugins_error(plugin_manager: CondaPluginManager):
-    # first load the plugin once
-    plugin_manager.load_plugins(VerboseSolverPlugin)
-    # then try again to trigger a PluginError via the `ValueError` that
-    # pluggy.PluginManager.register throws on duplicate plugins
-    with pytest.raises(
-        PluginError, match="Error while loading first-party conda plugin"
-    ):
-        plugin_manager.load_plugins(VerboseSolverPlugin)
+    assert plugin_manager.load_plugins(VerboseSolverPlugin) == 1
     assert plugin_manager.get_plugins() == {VerboseSolverPlugin}
 
 
@@ -150,15 +140,11 @@ def test_load_entrypoints_blocked(plugin_manager: CondaPluginManager):
 
 def test_load_entrypoints_register_valueerror(plugin_manager: CondaPluginManager):
     """
-    Cover check when self.register() raises ValueError.
+    Cover check when self.register() raises ValueError because the plugin
+    was loaded already.
     """
-
-    def raises_value_error(*args):
-        raise ValueError("bad plugin?")
-
-    plugin_manager.register = raises_value_error
-    with pytest.raises(PluginError):
-        plugin_manager.load_entrypoints("test_plugin", "success")
+    assert plugin_manager.load_entrypoints("test_plugin", "success") == 1
+    assert plugin_manager.load_entrypoints("test_plugin", "success") == 0
 
 
 def test_unknown_solver(plugin_manager: CondaPluginManager):
@@ -173,7 +159,7 @@ def test_known_solver(plugin_manager: CondaPluginManager):
     """
     Cover getting a solver that exists.
     """
-    plugin_manager.load_plugins(VerboseSolverPlugin)
+    assert plugin_manager.load_plugins(VerboseSolverPlugin) == 1
     assert plugin_manager.get_solver_backend("verbose-classic") == VerboseSolver
 
 
@@ -214,17 +200,17 @@ def test_disable_external_plugins(plugin_manager: CondaPluginManager, plugin: ob
 
 
 def test_get_virtual_packages(plugin_manager: CondaPluginManager):
-    plugin_manager.load_plugins(DummyVirtualPackagePlugin)
+    assert plugin_manager.load_plugins(DummyVirtualPackagePlugin) == 1
     assert plugin_manager.get_virtual_packages() == (DummyVirtualPackage,)
 
 
 def test_get_virtual_packages_no_name(plugin_manager: CondaPluginManager):
-    plugin_manager.load_plugins(NoNameVirtualPackagePlugin)
+    assert plugin_manager.load_plugins(NoNameVirtualPackagePlugin) == 1
     with pytest.raises(PluginError, match="Invalid plugin names"):
         plugin_manager.get_virtual_packages()
 
 
 def test_get_solvers(plugin_manager: CondaPluginManager):
-    plugin_manager.load_plugins(VerboseSolverPlugin)
+    assert plugin_manager.load_plugins(VerboseSolverPlugin) == 1
     assert plugin_manager.get_plugins() == {VerboseSolverPlugin}
     assert plugin_manager.get_solvers() == {"verbose-classic": VerboseCondaSolver}

tests/plugins/test_subcommands.py

@@ -13,7 +13,6 @@
 from conda.auxlib.ish import dals
 from conda.base.context import context
 from conda.cli.conda_argparse import BUILTIN_COMMANDS, generate_parser
-from conda.exceptions import PluginError
 from conda.plugins.types import CondaSubcommand
 from conda.testing import CondaCLIFixture
 
@@ -76,14 +75,12 @@ def test_duplicated(plugin_manager, conda_cli: CondaCLIFixture):
     plugin = SubcommandPlugin(name="custom", summary="Summary.")
     assert plugin_manager.load_plugins(plugin) == 1
 
-    # invalid, identical plugins
-    with pytest.raises(PluginError, match="Error while loading first-party"):
-        plugin_manager.load_plugins(plugin)
+    # invalid, identical plugins, error ignored
+    assert plugin_manager.load_plugins(plugin) == 0
 
-    # invalid, similar plugins
+    # invalid, similar plugins, error ignored
     plugin2 = SubcommandPlugin(name="custom", summary="Summary.")
-    with pytest.raises(PluginError, match="Error while loading first-party"):
-        plugin_manager.load_plugins(plugin2)
+    assert plugin_manager.load_plugins(plugin2) == 0
 
 
 @pytest.mark.parametrize("command", BUILTIN_COMMANDS)