From 4b29a3d747f354d3ab81f62674964b4678d37b5b Mon Sep 17 00:00:00 2001
From: John Roesler <johnrroesler@gmail.com>
Date: Thu, 20 Oct 2022 11:21:44 -0500
Subject: [PATCH 1/3] if job chains are used improperly we can end up with jobs
 with nil functions

---
 executor.go  | 6 ++++--
 scheduler.go | 7 +++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/executor.go b/executor.go
index e9aafd57..886d8d98 100644
--- a/executor.go
+++ b/executor.go
@@ -2,6 +2,7 @@ package gocron
 
 import (
 	"context"
+	"log"
 	"sync"
 
 	"golang.org/x/sync/semaphore"
@@ -47,6 +48,8 @@ func (e *executor) start() {
 		case f := <-e.jobFunctions:
 			runningJobsWg.Add(1)
 			go func() {
+				defer runningJobsWg.Done()
+
 				panicHandlerMutex.RLock()
 				defer panicHandlerMutex.RUnlock()
 
@@ -58,8 +61,6 @@ func (e *executor) start() {
 					}()
 				}
 
-				defer runningJobsWg.Done()
-
 				if e.maxRunningJobs != nil {
 					if !e.maxRunningJobs.TryAcquire(1) {
 
@@ -106,6 +107,7 @@ func (e *executor) start() {
 							return nil, nil
 						default:
 						}
+						log.Printf("executor jobFunction: %+v\n", f)
 						runJob()
 						return nil, nil
 					})
diff --git a/scheduler.go b/scheduler.go
index 6c249c74..f7a86d9c 100644
--- a/scheduler.go
+++ b/scheduler.go
@@ -539,6 +539,13 @@ func (s *Scheduler) run(job *Job) {
 	}
 
 	job.mu.Lock()
+
+	if job.function == nil {
+		job.mu.Unlock()
+		s.Remove(job)
+		return
+	}
+
 	defer job.mu.Unlock()
 
 	if job.runWithDetails {

From aaa45a9c2b452e6c49547764ede7eb1ddac14c72 Mon Sep 17 00:00:00 2001
From: John Roesler <johnrroesler@gmail.com>
Date: Thu, 20 Oct 2022 11:24:00 -0500
Subject: [PATCH 2/3] Update executor.go

---
 executor.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/executor.go b/executor.go
index 886d8d98..cded2212 100644
--- a/executor.go
+++ b/executor.go
@@ -107,7 +107,6 @@ func (e *executor) start() {
 							return nil, nil
 						default:
 						}
-						log.Printf("executor jobFunction: %+v\n", f)
 						runJob()
 						return nil, nil
 					})

From d3b1299c0dcfb83158cb997eedd789315f87ac5e Mon Sep 17 00:00:00 2001
From: John Roesler <johnrroesler@gmail.com>
Date: Thu, 20 Oct 2022 11:24:14 -0500
Subject: [PATCH 3/3] Update executor.go

---
 executor.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/executor.go b/executor.go
index cded2212..642095b1 100644
--- a/executor.go
+++ b/executor.go
@@ -2,7 +2,6 @@ package gocron
 
 import (
 	"context"
-	"log"
 	"sync"
 
 	"golang.org/x/sync/semaphore"