From 44657b78c40475e60187b48157bae41ea5371252 Mon Sep 17 00:00:00 2001
From: flywind <xzsflywind@gmail.com>
Date: Thu, 15 Apr 2021 01:14:14 +0800
Subject: [PATCH] callback cannot be nil (#17718)

`Task.callback` cannot be nil, we need to raise it at debug and release mode

Situations:
- if users create a Task object without using `toTask` and invoke the Task
- if users already move the Task and invoke the Task
---
 lib/std/tasks.nim | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/std/tasks.nim b/lib/std/tasks.nim
index 6b7f86ce47..aed36f985e 100644
--- a/lib/std/tasks.nim
+++ b/lib/std/tasks.nim
@@ -75,6 +75,7 @@ proc `=destroy`*(t: var Task) {.inline.} =
 
 proc invoke*(task: Task) {.inline.} =
   ## Invokes the `task`.
+  assert task.callback != nil
   task.callback(task.args)
 
 template checkIsolate(scratchAssignList: seq[NimNode], procParam, scratchDotExpr: NimNode) =