Set buffer_pointer to None when buffer doesn't exist

This enforces us to check that buffer_pointer is set, so we don't
accidentally operate on the core buffer, which is what is done when
buffer_pointer is an empty string.

4 files changed, 39 insertions, 28 deletions

diff --git a/slack/commands.py b/slack/commands.py
index ed57953..a866894 100644
--- a/slack/commands.py
+++ b/slack/commands.py
@@ -573,13 +573,13 @@ def completion_thread_hashes_cb(
     return weechat.WEECHAT_RC_OK
 
 
-def complete_input(slack_buffer: SlackBuffer, query: str):
+def complete_input(buffer: str, slack_buffer: SlackBuffer, query: str):
     if (
         slack_buffer.completion_context == "ACTIVE_COMPLETION"
         and slack_buffer.completion_values
     ):
-        input_value = weechat.buffer_get_string(slack_buffer.buffer_pointer, "input")
-        input_pos = weechat.buffer_get_integer(slack_buffer.buffer_pointer, "input_pos")
+        input_value = weechat.buffer_get_string(buffer, "input")
+        input_pos = weechat.buffer_get_integer(buffer, "input_pos")
         result = slack_buffer.completion_values[slack_buffer.completion_index]
         input_before = removesuffix(input_value[:input_pos], query)
         input_after = input_value[input_pos:]
@@ -587,8 +587,8 @@ def complete_input(slack_buffer: SlackBuffer, query: str):
         new_pos = input_pos - len(query) + len(result)
 
         with slack_buffer.completing():
-            weechat.buffer_set(slack_buffer.buffer_pointer, "input", new_input)
-            weechat.buffer_set(slack_buffer.buffer_pointer, "input_pos", str(new_pos))
+            weechat.buffer_set(buffer, "input", new_input)
+            weechat.buffer_set(buffer, "input_pos", str(new_pos))
 
 
 def nick_suffix():
@@ -598,7 +598,7 @@ def nick_suffix():
 
 
 async def complete_user_next(
-    slack_buffer: SlackBuffer, query: str, is_first_word: bool
+    buffer: str, slack_buffer: SlackBuffer, query: str, is_first_word: bool
 ):
     if slack_buffer.completion_context == "NO_COMPLETION":
         slack_buffer.completion_context = "PENDING_COMPLETION"
@@ -618,15 +618,15 @@ async def complete_user_next(
         if slack_buffer.completion_index >= len(slack_buffer.completion_values):
             slack_buffer.completion_index = 0
 
-    complete_input(slack_buffer, query)
+    complete_input(buffer, slack_buffer, query)
 
 
-def complete_previous(slack_buffer: SlackBuffer, query: str) -> int:
+def complete_previous(buffer: str, slack_buffer: SlackBuffer, query: str) -> int:
     if slack_buffer.completion_context == "ACTIVE_COMPLETION":
         slack_buffer.completion_index -= 1
         if slack_buffer.completion_index < 0:
             slack_buffer.completion_index = len(slack_buffer.completion_values) - 1
-        complete_input(slack_buffer, query)
+        complete_input(buffer, slack_buffer, query)
         return weechat.WEECHAT_RC_OK_EAT
     return weechat.WEECHAT_RC_OK
 
@@ -661,10 +661,12 @@ def input_complete_cb(data: str, buffer: str, command: str) -> int:
             is_first_word = word_until_cursor == input_before_cursor
 
             if command == "/input complete_next":
-                run_async(complete_user_next(slack_buffer, query, is_first_word))
+                run_async(
+                    complete_user_next(buffer, slack_buffer, query, is_first_word)
+                )
                 return weechat.WEECHAT_RC_OK_EAT
             else:
-                return complete_previous(slack_buffer, query)
+                return complete_previous(buffer, slack_buffer, query)
     return weechat.WEECHAT_RC_OK
 
 
diff --git a/slack/slack_buffer.py b/slack/slack_buffer.py
index fad5689..3c78ba3 100644
--- a/slack/slack_buffer.py
+++ b/slack/slack_buffer.py
@@ -151,7 +151,7 @@ class SlackBuffer(ABC):
     def __init__(self):
         self._typing_self_last_sent = 0
         # TODO: buffer_pointer may be accessed by buffer_switch before it's initialized
-        self.buffer_pointer: str = ""
+        self.buffer_pointer: Optional[str] = None
         self.is_loading = False
         self.history_pending = False
         self.history_pending_messages: List[SlackMessage] = []
@@ -273,6 +273,9 @@ class SlackBuffer(ABC):
             await self.buffer_switched_to()
 
     def update_buffer_props(self) -> None:
+        if self.buffer_pointer is None:
+            return
+
         name, buffer_props = self.get_name_and_buffer_props()
         buffer_props["name"] = self.get_full_name(name)
         for key, value in buffer_props.items():
@@ -283,6 +286,9 @@ class SlackBuffer(ABC):
         raise NotImplementedError()
 
     async def rerender_message(self, message: SlackMessage):
+        if self.buffer_pointer is None:
+            return
+
         modify_buffer_line(
             self.buffer_pointer,
             message.ts,
@@ -349,7 +355,7 @@ class SlackBuffer(ABC):
     def ts_from_index(
         self, index: int, message_filter: Optional[Literal["sender_self"]] = None
     ) -> Optional[SlackTs]:
-        if index < 0:
+        if index < 0 or self.buffer_pointer is None:
             return
 
         lines = weechat.hdata_pointer(
@@ -498,7 +504,7 @@ class SlackBuffer(ABC):
     def _buffer_close_cb(self, data: str, buffer: str) -> int:
         if self.buffer_pointer in shared.buffers:
             del shared.buffers[self.buffer_pointer]
-        self.buffer_pointer = ""
+        self.buffer_pointer = None
         self.last_printed_ts = None
         self.hotlist_tss.clear()
         return weechat.WEECHAT_RC_OK
diff --git a/slack/slack_conversation.py b/slack/slack_conversation.py
index 8b2bb67..2c95f4c 100644
--- a/slack/slack_conversation.py
+++ b/slack/slack_conversation.py
@@ -555,7 +555,7 @@ class SlackConversation(SlackBuffer):
                     self.nicklist_add_nick(user.nick)
 
     def nicklist_add_nick(self, nick: Nick):
-        if nick in self._nicklist or self.type == "im":
+        if nick in self._nicklist or self.type == "im" or self.buffer_pointer is None:
             return
 
         # TODO: weechat.color.nicklist_away
@@ -568,25 +568,27 @@ class SlackConversation(SlackBuffer):
         self._nicklist[nick] = nick_pointer
 
     def nicklist_remove_nick(self, nick: Nick):
-        if self.type == "im":
+        if self.type == "im" or self.buffer_pointer is None:
             return
         nick_pointer = self._nicklist.pop(nick)
         weechat.nicklist_remove_nick(self.buffer_pointer, nick_pointer)
 
     def display_thread_replies(self) -> bool:
-        buffer_value = weechat.buffer_get_string(
-            self.buffer_pointer, "localvar_display_thread_replies_in_channel"
-        )
-        if buffer_value:
-            return bool(weechat.config_string_to_boolean(buffer_value))
+        if self.buffer_pointer is not None:
+            buffer_value = weechat.buffer_get_string(
+                self.buffer_pointer, "localvar_display_thread_replies_in_channel"
+            )
+            if buffer_value:
+                return bool(weechat.config_string_to_boolean(buffer_value))
         return shared.config.look.display_thread_replies_in_channel.value
 
     def display_reaction_nicks(self) -> bool:
-        buffer_value = weechat.buffer_get_string(
-            self.buffer_pointer, "localvar_display_reaction_nicks"
-        )
-        if buffer_value:
-            return bool(weechat.config_string_to_boolean(buffer_value))
+        if self.buffer_pointer is not None:
+            buffer_value = weechat.buffer_get_string(
+                self.buffer_pointer, "localvar_display_reaction_nicks"
+            )
+            if buffer_value:
+                return bool(weechat.config_string_to_boolean(buffer_value))
         return shared.config.look.display_reaction_nicks.value
 
     def should_display_message(self, message: SlackMessage) -> bool:
@@ -605,7 +607,7 @@ class SlackConversation(SlackBuffer):
                 self.history_pending_messages.append(message)
             elif self.last_printed_ts is not None:
                 await self.print_message(message)
-            else:
+            elif self.buffer_pointer is not None:
                 weechat.buffer_set(
                     self.buffer_pointer, "hotlist", message.priority.value
                 )
diff --git a/slack/slack_workspace.py b/slack/slack_workspace.py
index 7299857..145a008 100644
--- a/slack/slack_workspace.py
+++ b/slack/slack_workspace.py
@@ -549,7 +549,8 @@ class SlackWorkspace:
                 or data["type"] == "channel_left"
                 or data["type"] == "group_left"
             ):
-                weechat.buffer_close(channel.buffer_pointer)
+                if channel.buffer_pointer is not None:
+                    weechat.buffer_close(channel.buffer_pointer)
             elif data["type"] == "reaction_added" and data["item"]["type"] == "message":
                 await channel.reaction_add(
                     SlackTs(data["item"]["ts"]), data["reaction"], data["user"]