From 50cfd9d9dd82cb8dda954a06235d199fd20cf7be Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Tue, 27 Jun 2023 14:44:03 +0200
Subject: [PATCH] `untilCancelled` template

---
 ethers/providers/jsonrpc/looping.nim       |  6 ++++++
 ethers/providers/jsonrpc/subscriptions.nim | 12 +++++-------
 2 files changed, 11 insertions(+), 7 deletions(-)
 create mode 100644 ethers/providers/jsonrpc/looping.nim

diff --git a/ethers/providers/jsonrpc/looping.nim b/ethers/providers/jsonrpc/looping.nim
new file mode 100644
index 0000000..f0bb7a8
--- /dev/null
+++ b/ethers/providers/jsonrpc/looping.nim
@@ -0,0 +1,6 @@
+template untilCancelled*(body) =
+  try:
+    while true:
+      body
+  except CancelledError:
+    raise
diff --git a/ethers/providers/jsonrpc/subscriptions.nim b/ethers/providers/jsonrpc/subscriptions.nim
index e24ead5..c0e92c2 100644
--- a/ethers/providers/jsonrpc/subscriptions.nim
+++ b/ethers/providers/jsonrpc/subscriptions.nim
@@ -6,6 +6,7 @@ import ../../basics
 import ../../provider
 import ./rpccalls
 import ./conversions
+import ./looping
 
 type
   JsonRpcSubscriptions* = ref object of RootObj
@@ -110,13 +111,10 @@ proc new*(_: type JsonRpcSubscriptions,
         callback(id, change)
 
   proc poll {.async.} =
-    try:
-      while true:
-        for id in toSeq subscriptions.callbacks.keys:
-          await poll(id)
-        await sleepAsync(pollingInterval)
-    except CancelledError:
-      raise
+    untilCancelled:
+      for id in toSeq subscriptions.callbacks.keys:
+        await poll(id)
+      await sleepAsync(pollingInterval)
 
   asyncSpawn poll()