From b240a84ce009a53fee3c941ca5f696344e4c5d83 Mon Sep 17 00:00:00 2001
From: Arthur Barr <arthur.barr@uk.ibm.com>
Date: Mon, 12 Mar 2018 16:28:40 +0000
Subject: [PATCH] Fix occasional timing error in tests

---
 test/docker/docker_api_test_util.go | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/test/docker/docker_api_test_util.go b/test/docker/docker_api_test_util.go
index 7c54b3e..5409b45 100644
--- a/test/docker/docker_api_test_util.go
+++ b/test/docker/docker_api_test_util.go
@@ -309,13 +309,23 @@ func execContainerWithOutput(t *testing.T, cli *client.Client, ID string, user s
 	if err != nil {
 		t.Fatal(err)
 	}
-	cli.ContainerExecStart(context.Background(), resp.ID, types.ExecStartCheck{
+	err = cli.ContainerExecStart(context.Background(), resp.ID, types.ExecStartCheck{
 		Detach: false,
 		Tty:    false,
 	})
 	if err != nil {
 		t.Fatal(err)
 	}
+	// Wait for the command to finish
+	for {
+		inspect, err := cli.ContainerExecInspect(context.Background(), resp.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !inspect.Running {
+			break
+		}
+	}
 	buf := new(bytes.Buffer)
 	// Each output line has a header, which needs to be removed
 	_, err = stdcopy.StdCopy(buf, buf, hijack.Reader)