diff --git a/nonebot/plugin/manager.py b/nonebot/plugin/manager.py
index f359db57..260ce9fc 100644
--- a/nonebot/plugin/manager.py
+++ b/nonebot/plugin/manager.py
@@ -98,7 +98,7 @@ class PluginManager:
 
         return third_party_plugins | set(self.searched_plugins.keys())
 
-    def load_plugin(self, name) -> Optional[Plugin]:
+    def load_plugin(self, name: str) -> Optional[Plugin]:
         try:
             if name in self.plugins:
                 module = importlib.import_module(name)
diff --git a/tests/test_init.py b/tests/test_init.py
index 1d241728..6d36dccd 100644
--- a/tests/test_init.py
+++ b/tests/test_init.py
@@ -1,12 +1,7 @@
 import os
-import sys
-from typing import TYPE_CHECKING, Set
 
 import pytest
 
-if TYPE_CHECKING:
-    from nonebot.plugin import Plugin
-
 os.environ["CONFIG_FROM_ENV"] = '{"test": "test"}'
 
 
@@ -74,25 +69,3 @@ async def test_get(monkeypatch: pytest.MonkeyPatch, nonebug_clear):
     assert get_bot() == "test"
     assert get_bot("test") == "test"
     assert get_bots() == {"test": "test"}
-
-
-@pytest.mark.asyncio
-async def test_load_plugin(load_plugin: Set["Plugin"]):
-    import nonebot
-
-    loaded_plugins = set(
-        plugin for plugin in nonebot.get_loaded_plugins() if not plugin.parent_plugin
-    )
-    assert loaded_plugins == load_plugin
-    plugin = nonebot.get_plugin("export")
-    assert plugin
-    assert plugin.module_name == "plugins.export"
-    assert "plugins.export" in sys.modules
-
-    try:
-        nonebot.load_plugin("plugins.export")
-        assert False
-    except RuntimeError:
-        assert True
-
-    assert nonebot.load_plugin("some_plugin_no_exist") is None
diff --git a/tests/test_plugin/test_load.py b/tests/test_plugin/test_load.py
new file mode 100644
index 00000000..c0c0c8f6
--- /dev/null
+++ b/tests/test_plugin/test_load.py
@@ -0,0 +1,89 @@
+import sys
+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_load_plugin(load_plugin: Set["Plugin"]):
+    import nonebot
+
+    loaded_plugins = set(
+        plugin for plugin in nonebot.get_loaded_plugins() if not plugin.parent_plugin
+    )
+    assert loaded_plugins == load_plugin
+    plugin = nonebot.get_plugin("export")
+    assert plugin
+    assert plugin.module_name == "plugins.export"
+    assert "plugins.export" in sys.modules
+
+    try:
+        nonebot.load_plugin("plugins.export")
+        assert False
+    except RuntimeError:
+        assert True
+
+    assert nonebot.load_plugin("some_plugin_not_exist") is None
+
+
+@pytest.mark.asyncio
+async def test_require_loaded(app: App, monkeypatch: pytest.MonkeyPatch):
+    import nonebot
+
+    def _patched_find(name: str):
+        assert False
+
+    monkeypatch.setattr("nonebot.plugin.load._find_manager_by_name", _patched_find)
+
+    nonebot.load_plugin("plugins.export")
+
+    nonebot.require("plugins.export")
+
+
+@pytest.mark.asyncio
+async def test_require_not_loaded(app: App, monkeypatch: pytest.MonkeyPatch):
+    import nonebot
+    from nonebot.plugin import _managers
+    from nonebot.plugin.manager import PluginManager
+
+    m = PluginManager(["plugins.export"])
+    _managers.append(m)
+
+    origin_load = PluginManager.load_plugin
+
+    def _patched_load(self: PluginManager, name: str):
+        assert self is m
+        return origin_load(self, name)
+
+    monkeypatch.setattr(PluginManager, "load_plugin", _patched_load)
+
+    nonebot.require("plugins.export")
+
+    assert len(_managers) == 1
+
+
+@pytest.mark.asyncio
+async def test_require_not_declared(app: App):
+    import nonebot
+    from nonebot.plugin import _managers
+
+    nonebot.require("plugins.export")
+
+    assert len(_managers) == 1
+    assert _managers[-1].plugins == {"plugins.export"}
+
+
+@pytest.mark.asyncio
+async def test_require_not_found(app: App):
+    import nonebot
+    from nonebot.plugin import _managers
+
+    try:
+        nonebot.require("some_plugin_not_exist")
+        assert False
+    except RuntimeError:
+        assert True