Add argfilter type "controllers"

nonebot/command/argfilter/controllers.py

@@ -0,0 +1,34 @@
+import re
+
+from nonebot import CommandSession
+from nonebot.helpers import render_expression
+
+
+def handle_cancellation(session: CommandSession):
+    """
+    If the input is a string of cancellation word, finish the command session.
+    """
+
+    def control(value):
+        if _is_cancellation(value):
+            session.finish(render_expression(
+                session.bot.config.SESSION_CANCEL_EXPRESSION))
+        return value
+
+    return control
+
+
+async def _is_cancellation(sentence: str) -> bool:
+    for kw in ('算', '别', '不', '停', '取消'):
+        if kw in sentence:
+            # a keyword matches
+            break
+    else:
+        # no keyword matches
+        return False
+
+    if re.match(r'^那?[算别不停]\w{0,3}了?吧?$', sentence) or \
+            re.match(r'^那?(?:[给帮]我)?取消了?吧?$', sentence):
+        return True
+
+    return False