From 883f09e31cca8bc2b59f6a700dd95b00bb514183 Mon Sep 17 00:00:00 2001
From: jesopo <github@lolnerd.net>
Date: Sun, 21 Jun 2020 16:46:36 +0100
Subject: [PATCH] switch _next_lines and _read_lines to generators. taskgroup
 wait_fors!

---
 ircrobots/bot.py    |  3 +-
 ircrobots/server.py | 75 +++++++++++++++++++++++----------------------
 2 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/ircrobots/bot.py b/ircrobots/bot.py
index a65cbd5..6ea6b97 100644
--- a/ircrobots/bot.py
+++ b/ircrobots/bot.py
@@ -39,7 +39,8 @@ class Bot(IBot):
         async with anyio.create_task_group() as tg:
             async def _read():
                 while True:
-                    await server._read_lines()
+                    async for line, emit in server._read_lines():
+                        pass
             await tg.spawn(_read)
             await tg.spawn(server._send_lines)
 
diff --git a/ircrobots/server.py b/ircrobots/server.py
index 3fc3595..3d7927f 100644
--- a/ircrobots/server.py
+++ b/ircrobots/server.py
@@ -1,10 +1,11 @@
 import asyncio
 from asyncio     import Future, PriorityQueue
-from typing      import (Awaitable, Deque, Dict, List, Optional, Set, Tuple,
-    Union)
+from typing      import (AsyncIterable, Awaitable, Deque, Dict, Iterable, List,
+    Optional, Set, Tuple, Union)
 from collections import deque
 from time        import monotonic
 
+import anyio
 from asyncio_throttle   import Throttler
 from async_timeout      import timeout
 from ircstates          import Emit, Channel, ChannelUser
@@ -64,8 +65,8 @@ class Server(IServer):
 
         self._read_queue:  Deque[Tuple[Line, Optional[Emit]]] = deque()
 
-        self._wait_fors: List[Tuple[WaitFor, Optional[Awaitable]]] = []
-        self._wait_for_fut: Optional[Future[WaitFor]] = None
+        self._wait_fors: List[WaitFor] = []
+        self._wait_for_fut: Dict[str, Future[bool]] = {}
 
         self._pending_who: Deque[str] = deque()
 
@@ -200,7 +201,7 @@ class Server(IServer):
             line = await self.wait_for(end)
 
 
-    async def _next_lines(self) -> List[Tuple[Line, Optional[Emit]]]:
+    async def _next_lines(self) -> AsyncIterable[Tuple[Line, Optional[Emit]]]:
         ping_sent = False
         while True:
             try:
@@ -223,45 +224,46 @@ class Server(IServer):
                 self.disconnected = True
                 raise
 
-            return lines
+            for both in lines:
+                yield both
 
     async def _line_or_wait(self,
-            line_aw: Awaitable
-            ) -> Optional[Tuple[WaitFor, Awaitable]]:
-        wait_for_fut: Future[WaitFor] = Future()
-        self._wait_for_fut = wait_for_fut
+            line_aw: asyncio.Task
+            ) -> Optional[Awaitable]:
+        task_name = line_aw.get_name()
+        wait_for_fut: Future[bool] = Future()
+        self._wait_for_fut[task_name] = wait_for_fut
 
         done, pend = await asyncio.wait([line_aw, wait_for_fut],
             return_when=asyncio.FIRST_COMPLETED)
-        self._wait_for_fut = None
+        del self._wait_for_fut[task_name]
 
         if wait_for_fut.done():
             new_line_aw = list(pend)[0]
-            return (await wait_for_fut), new_line_aw
+            return new_line_aw
         else:
             return None
 
-    async def _read_lines(self) -> List[Tuple[Line, Optional[Emit]]]:
-        lines = await self._next_lines()
-        for line, emit in lines:
-            self.line_preread(line)
+    async def _read_lines(self) -> AsyncIterable[Tuple[Line, Optional[Emit]]]:
+        async with anyio.create_task_group() as tg:
+            async for both in self._next_lines():
+                line, emit = both
+                self.line_preread(line)
 
-            for i, (wait_for, aw) in enumerate(self._wait_fors):
-                if wait_for.match(self, line):
-                    wait_for.resolve(line)
+                for i, wait_for in enumerate(self._wait_fors):
+                    if wait_for.match(self, line):
+                        wait_for.resolve(line)
+                        self._wait_fors.pop(i)
+                        break
 
-                    if aw is not None:
-                        new_wait_for = await self._line_or_wait(aw)
-                        if new_wait_for is not None:
-                            self._wait_fors.append(new_wait_for)
-                    self._wait_fors.pop(i)
-                    break
+                line_aw = asyncio.create_task(self._on_read(line, emit))
+                new_wait = await self._line_or_wait(line_aw)
+                if new_wait is not None:
+                    async def _aw():
+                        await new_wait
+                    await tg.spawn(_aw)
 
-            line_aw = self._on_read(line, emit)
-            new_wait_for = await self._line_or_wait(line_aw)
-            if new_wait_for is not None:
-                self._wait_fors.append(new_wait_for)
-        return lines
+                yield both
 
     async def wait_for(self,
             response: Union[IMatchResponse, Set[IMatchResponse]],
@@ -275,13 +277,14 @@ class Server(IServer):
             response_obj = response
 
         our_wait_for = WaitFor(response_obj)
+        self._wait_fors.append(our_wait_for)
 
-        wait_for_fut = self._wait_for_fut
-        if wait_for_fut is not None:
-            self._wait_for_fut = None
-            wait_for_fut.set_result(our_wait_for)
-        else:
-            self._wait_fors.append((our_wait_for, None))
+        cur_task = asyncio.current_task()
+        if cur_task is not None:
+            cur_task_name = cur_task.get_name()
+            if cur_task_name in self._wait_for_fut:
+                wait_for_fut = self._wait_for_fut[cur_task_name]
+                wait_for_fut.set_result(True)
 
         if sent_aw is not None:
             sent_line = await sent_aw