From a07059c7694ad81c7f49ee6d3f48a9ecaf8582d7 Mon Sep 17 00:00:00 2001
From: Arseny Balobanov <verytable@yandex.ru>
Date: Sat, 15 Feb 2020 23:18:14 +0300
Subject: [PATCH] Replace context in WaitForPort with timeout.

---
 digitalclock/main_test.go       |  8 +-------
 tools/testtool/freeport.go      | 14 ++++++++------
 tools/testtool/freeport_test.go | 15 ++-------------
 3 files changed, 11 insertions(+), 26 deletions(-)

diff --git a/digitalclock/main_test.go b/digitalclock/main_test.go
index 20e8bff..83b83d8 100644
--- a/digitalclock/main_test.go
+++ b/digitalclock/main_test.go
@@ -1,7 +1,6 @@
 package main
 
 import (
-	"context"
 	"encoding/json"
 	"fmt"
 	"image"
@@ -58,12 +57,7 @@ func startServer(t *testing.T) (port string, stop func()) {
 		<-done
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second*30)
-	defer cancel()
-
-	testtool.WaitForPort(ctx, port)
-	if ctx.Err() != nil {
-		err = ctx.Err()
+	if err = testtool.WaitForPort(time.Second*30, port); err != nil {
 		stop()
 	}
 
diff --git a/tools/testtool/freeport.go b/tools/testtool/freeport.go
index 8f07e38..b31ef87 100644
--- a/tools/testtool/freeport.go
+++ b/tools/testtool/freeport.go
@@ -1,7 +1,6 @@
 package testtool
 
 import (
-	"context"
 	"fmt"
 	"net"
 	"os"
@@ -29,21 +28,24 @@ func GetFreePort() (string, error) {
 
 // WaitForPort tries to connect to given local port with constant backoff.
 //
-// Can be canceled via ctx.
-func WaitForPort(ctx context.Context, port string) {
+// Returns error if port is not ready after timeout.
+func WaitForPort(timeout time.Duration, port string) error {
+	stopTimer := time.NewTimer(timeout)
+	defer stopTimer.Stop()
+
 	t := time.NewTicker(time.Millisecond * 100)
 	defer t.Stop()
 
 	for {
 		select {
-		case <-ctx.Done():
-			return
+		case <-stopTimer.C:
+			return fmt.Errorf("timeout")
 		case <-t.C:
 			if err := portIsReady(port); err != nil {
 				_, _ = fmt.Fprintf(os.Stderr, "waiting for port: %s\n", err)
 				break
 			}
-			return
+			return nil
 		}
 	}
 }
diff --git a/tools/testtool/freeport_test.go b/tools/testtool/freeport_test.go
index 4314c3b..f9cbbbb 100644
--- a/tools/testtool/freeport_test.go
+++ b/tools/testtool/freeport_test.go
@@ -1,7 +1,6 @@
 package testtool
 
 import (
-	"context"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -27,22 +26,12 @@ func TestWaitForPort(t *testing.T) {
 	_, port, err := net.SplitHostPort(u.Host)
 	require.Nil(t, err)
 
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-
-	WaitForPort(ctx, port)
-
-	require.NoError(t, ctx.Err())
+	require.NoError(t, WaitForPort(time.Second, port))
 }
 
 func TestWaitForPort_timeout(t *testing.T) {
 	p, err := GetFreePort()
 	require.NoError(t, err)
 
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-
-	WaitForPort(ctx, p)
-
-	require.Error(t, ctx.Err())
+	require.Error(t, WaitForPort(time.Second, p))
 }