⚡ improve plugin system (#1011)

tests/test_plugin/test_get.py

@@ -0,0 +1,39 @@
+from typing import TYPE_CHECKING, Set
+
+import pytest
+from nonebug import App
+
+if TYPE_CHECKING:
+    from nonebot.plugin import Plugin
+
+
+@pytest.mark.asyncio
+async def test_get_plugin(app: App, load_plugin: Set["Plugin"]):
+    import nonebot
+
+    # check simple plugin
+    plugin = nonebot.get_plugin("export")
+    assert plugin
+    assert plugin.module_name == "plugins.export"
+
+    # check sub plugin
+    plugin = nonebot.get_plugin("nested_subplugin")
+    assert plugin
+    assert plugin.module_name == "plugins.nested.plugins.nested_subplugin"
+
+    # check get plugin by module name
+    plugin = nonebot.get_plugin_by_module_name("plugins.nested.utils")
+    assert plugin
+    assert plugin.module_name == "plugins.nested"
+
+
+@pytest.mark.asyncio
+async def test_get_available_plugin(app: App):
+    import nonebot
+    from nonebot.plugin import PluginManager, _managers
+
+    _managers.append(PluginManager(["plugins.export", "plugin.require"]))
+
+    # check get available plugins
+    plugin_names = nonebot.get_available_plugin_names()
+    assert plugin_names == {"export", "require"}