From 601127071cc00253d0f444c338d32013c96e8c00 Mon Sep 17 00:00:00 2001
From: Eryn Lynn <eryn@eryn.io>
Date: Fri, 9 Nov 2018 00:00:40 -0500
Subject: [PATCH] Call cancellation hook immediately if already cancelled

---
 lib/init.lua | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/init.lua b/lib/init.lua
index 34efa19..e6ceb72 100644
--- a/lib/init.lua
+++ b/lib/init.lua
@@ -170,7 +170,11 @@ function Promise.new(callback, parent)
 	local function onCancel(cancellationHook)
 		assert(type(cancellationHook) == "function", "onCancel must be called with a function as its first argument.")
 
-		self._cancellationHook = cancellationHook
+		if self._status == Promise.Status.Cancelled then
+			cancellationHook()
+		else
+			self._cancellationHook = cancellationHook
+		end
 	end
 
 	local _, result = wpcallPacked(callback, resolve, reject, onCancel)