Add dictionary mapping command_id to its associated MenuCommands …

…for each plugin (#348)

Adding this dictionary to support quick mapping of widgets/commands to
their menus for implementing contributable menus . Prior to this PR, you
would have to search all menu contributions for the command of the
contribution you were currently processing. This map allows you direct
access to the menus this command needs to live in.

This is a precursor to potentially rearchitecting the manifest schema
entirely to be "command-first".

---------

Co-authored-by: Juan Nunez-Iglesias <[email protected]>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

src/npe2/_plugin_manager.py

@@ -4,7 +4,7 @@
 import os
 import urllib
 import warnings
-from collections import Counter
+from collections import Counter, defaultdict
 from fnmatch import fnmatch
 from importlib import metadata
 from logging import getLogger
@@ -38,6 +38,7 @@
 if TYPE_CHECKING:
     from .manifest.contributions import (
         CommandContribution,
+        MenuCommand,
         MenuItem,
         ReaderContribution,
         SampleDataContribution,
@@ -235,6 +236,9 @@ def __init__(
         self._manifests: Dict[PluginName, PluginManifest] = {}
         self.events = PluginManagerEvents(self)
         self._npe1_adapters: List[NPE1Adapter] = []
+        self._command_menu_map: Dict[
+            str, Dict[str, Dict[str, List[MenuCommand]]]
+        ] = defaultdict(dict)
 
         # up to napari 0.4.15, discovery happened in the init here
         # so if we're running on an older version of napari, we need to discover
@@ -358,14 +362,28 @@ def register(
             self._npe1_adapters.append(manifest)
         else:
             self._contrib.index_contributions(manifest)
+            self._populate_command_menu_map(manifest)
         self.events.plugins_registered.emit({manifest})
 
+    def _populate_command_menu_map(self, manifest: PluginManifest):
+        # map of manifest -> command -> menu_id -> list[items]
+        self._command_menu_map[manifest.name] = defaultdict(lambda: defaultdict(list))
+        menu_map = self._command_menu_map[manifest.name]  # just for conciseness below
+        for menu_id, menu_items in manifest.contributions.menus.items() or ():
+            # command IDs are keys in map
+            # each value is a dict menu_id: list of MenuCommands
+            # for the command and menu
+            for item in menu_items:
+                if (command_id := getattr(item, "command", None)) is not None:
+                    menu_map[command_id][menu_id].append(item)
+
     def unregister(self, key: PluginName):
         """Unregister plugin named `key`."""
         if key not in self._manifests:
             raise ValueError(f"No registered plugin named {key!r}")  # pragma: no cover
         self.deactivate(key)
         self._contrib.remove_contributions(key)
+        self._command_menu_map.pop(key)
         self._manifests.pop(key)
 
     def activate(self, key: PluginName) -> PluginContext:
@@ -448,6 +466,7 @@ def enable(self, plugin_name: PluginName) -> None:
         mf = self._manifests.get(plugin_name)
         if mf is not None:
             self._contrib.index_contributions(mf)
+            self._populate_command_menu_map(mf)
         self.events.enablement_changed({plugin_name}, {})
 
     def disable(self, plugin_name: PluginName) -> None:
@@ -467,6 +486,7 @@ def disable(self, plugin_name: PluginName) -> None:
 
         self._disabled_plugins.add(plugin_name)
         self._contrib.remove_contributions(plugin_name)
+        self._command_menu_map.pop(plugin_name)
         self.events.enablement_changed({}, {plugin_name})
 
     def is_disabled(self, plugin_name: str) -> bool:

tests/test_plugin_manager.py

@@ -236,3 +236,33 @@ def dummy_error():
     pm.get_context("test").register_disposable(dummy_error)
     pm.deactivate("test")
     assert caplog.records[0].msg == "Error while disposing test; This is an error"
+
+
+def test_command_menu_map(uses_sample_plugin, plugin_manager: PluginManager):
+    """Test that the command menu map is correctly populated."""
+    pm = PluginManager.instance()
+    assert SAMPLE_PLUGIN_NAME in pm._manifests
+    assert SAMPLE_PLUGIN_NAME in pm._command_menu_map
+
+    # contains correct commands
+    command_menu_map = pm._command_menu_map[SAMPLE_PLUGIN_NAME]
+    assert "my-plugin.hello_world" in command_menu_map
+    assert "my-plugin.another_command" in command_menu_map
+
+    # commands point to correct menus
+    assert len(cmd_menu := command_menu_map["my-plugin.hello_world"]) == 1
+    assert "/napari/layer_context" in cmd_menu
+    assert len(cmd_menu := command_menu_map["my-plugin.another_command"]) == 1
+    assert "mysubmenu" in cmd_menu
+
+    # enable/disable
+    pm.disable(SAMPLE_PLUGIN_NAME)
+    assert SAMPLE_PLUGIN_NAME not in pm._command_menu_map
+    pm.enable(SAMPLE_PLUGIN_NAME)
+    assert SAMPLE_PLUGIN_NAME in pm._command_menu_map
+
+    # register/unregister
+    pm.unregister(SAMPLE_PLUGIN_NAME)
+    assert SAMPLE_PLUGIN_NAME not in pm._command_menu_map
+    pm.register(SAMPLE_PLUGIN_NAME)
+    assert SAMPLE_PLUGIN_NAME in pm._command_menu_map