Add support for thread parameter in Webhook.send

discord/webhook/sync.py

@@ -262,9 +262,12 @@ class WebhookAdapter:
         payload: Optional[Dict[str, Any]] = None,
         multipart: Optional[List[Dict[str, Any]]] = None,
         files: Optional[List[File]] = None,
+        thread_id: Optional[int] = None,
         wait: bool = False,
     ):
         params = {'wait': int(wait)}
+        if thread_id:
+            params['thread_id'] = thread_id
         route = Route('POST', '/webhooks/{webhook_id}/{webhook_token}', webhook_id=webhook_id, webhook_token=token)
         return self.request(route, session, payload=payload, multipart=multipart, files=files, params=params)
 
@@ -780,6 +783,7 @@ class SyncWebhook(BaseWebhook):
         embed: Embed = MISSING,
         embeds: List[Embed] = MISSING,
         allowed_mentions: AllowedMentions = MISSING,
+        thread: Snowflake = MISSING,
         wait: bool = False,
     ) -> Optional[SyncWebhookMessage]:
         """Sends a message using the webhook.
@@ -824,6 +828,10 @@ class SyncWebhook(BaseWebhook):
             Controls the mentions being processed in this message.
 
             .. versionadded:: 1.4
+        thread: :class:`~discord.abc.Snowflake`
+            The thread to send this message to.
+
+            .. versionadded:: 2.0
 
         Raises
         --------
@@ -866,6 +874,10 @@ class SyncWebhook(BaseWebhook):
             previous_allowed_mentions=previous_mentions,
         )
         adapter: WebhookAdapter = _context.adapter
+        thread_id: Optional[int] = None
+        if thread is not MISSING:
+            thread_id = thread.id
+
         data = adapter.execute_webhook(
             self.id,
             self.token,
@@ -873,6 +885,7 @@ class SyncWebhook(BaseWebhook):
             payload=params.payload,
             multipart=params.multipart,
             files=params.files,
+            thread_id=thread_id,
             wait=wait,
         )
         if wait: