From 0b79c61a8920cdcb9b6c77087e2d94628ba0c0b9 Mon Sep 17 00:00:00 2001
From: Rohan Verma <hello@rohanverma.net>
Date: Thu, 15 Oct 2020 21:12:17 +0530
Subject: [PATCH] fix: open connection count

This commit releases back the connection in the special
case, so that correct count is always maintained.
---
 redis/pool.go      |  1 +
 redis/pool_test.go | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/redis/pool.go b/redis/pool.go
index 4a468cf0..c6c56f43 100644
--- a/redis/pool.go
+++ b/redis/pool.go
@@ -387,6 +387,7 @@ func (p *Pool) waitVacantConn(ctx context.Context) (waited time.Duration, err er
 		// because `select` picks a random `case` if several of them are "ready".
 		select {
 		case <-ctx.Done():
+			p.ch <- struct{}{}
 			return 0, ctx.Err()
 		default:
 		}
diff --git a/redis/pool_test.go b/redis/pool_test.go
index a8efa515..a8a8c2ff 100644
--- a/redis/pool_test.go
+++ b/redis/pool_test.go
@@ -825,6 +825,30 @@ func TestWaitPoolGetContext(t *testing.T) {
 	defer c.Close()
 }
 
+func TestWaitPoolGetContextIssue520(t *testing.T) {
+	d := poolDialer{t: t}
+	p := &redis.Pool{
+		MaxIdle:   1,
+		MaxActive: 1,
+		Dial:      d.dial,
+		Wait:      true,
+	}
+	defer p.Close()
+	ctx1, _ := context.WithTimeout(context.Background(), 1*time.Nanosecond)
+	c, err := p.GetContext(ctx1)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("GetContext returned %v", err)
+	}
+	defer c.Close()
+
+	ctx2, _ := context.WithCancel(context.Background())
+	c2, err := p.GetContext(ctx2)
+	if err != nil {
+		t.Fatalf("Get context returned %v", err)
+	}
+	defer c2.Close()
+}
+
 func TestWaitPoolGetContextWithDialContext(t *testing.T) {
 	d := poolDialer{t: t}
 	p := &redis.Pool{