fix: semaphore (#95)

* fix: version

* fix: semaphore value

* chore: bump version to 0.8.2

* fix: "attached to a different loop" edge case

multicall/utils.py

@@ -10,8 +10,8 @@
 from web3.eth import AsyncEth
 from web3.providers.async_base import AsyncBaseProvider
 
-from multicall.constants import (AIOHTTP_TIMEOUT, NO_STATE_OVERRIDE,
-                                 NUM_PROCESSES)
+from multicall.constants import (AIOHTTP_TIMEOUT, ASYNC_SEMAPHORE, 
+                                 NO_STATE_OVERRIDE, NUM_PROCESSES)
 
 chainids: Dict[Web3,int] = {}
 
@@ -97,6 +97,11 @@ def state_override_supported(w3: Web3) -> bool:
         return False
     return True
 
-@lru_cache(maxsize=1)
 def _get_semaphore() -> asyncio.Semaphore:
-    return asyncio.Semaphore()
+    'Returns a `Semaphore` attached to the current event loop'
+    return __get_semaphore(asyncio.get_event_loop())
+
+@lru_cache(maxsize=1)
+def __get_semaphore(loop: asyncio.BaseEventLoop) -> asyncio.Semaphore:
+    'This prevents an "attached to a different loop" edge case if the event loop is changed during your script run'
+    return asyncio.Semaphore(ASYNC_SEMAPHORE)

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "multicall"
-version = "0.8.0"
+version = "0.8.2"
 description = "aggregate results from multiple ethereum contract calls"
 authors = ["banteg"]