From dd9ecbf4407d0a67f3052a6d195140d3fd7f71a6 Mon Sep 17 00:00:00 2001
From: James Phillips <slackpad@gmail.com>
Date: Thu, 26 Jan 2017 17:11:16 -0800
Subject: [PATCH] Run the waited-for function before sleeping, and ramp up the
 sleep exponentially.

---
 testutil/server.go |  1 -
 testutil/wait.go   | 21 +++++++++++++++------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/testutil/server.go b/testutil/server.go
index 3596af151..f97db7444 100644
--- a/testutil/server.go
+++ b/testutil/server.go
@@ -310,7 +310,6 @@ func (s *TestServer) waitForLeader() {
 
 		// Ensure we have a leader and a node registration.
 		if leader := resp.Header.Get("X-Consul-KnownLeader"); leader != "true" {
-			fmt.Println(leader)
 			return false, fmt.Errorf("Consul leader status: %#v", leader)
 		}
 		index, err = strconv.ParseInt(resp.Header.Get("X-Consul-Index"), 10, 64)
diff --git a/testutil/wait.go b/testutil/wait.go
index c4f137eba..f32562994 100644
--- a/testutil/wait.go
+++ b/testutil/wait.go
@@ -10,19 +10,28 @@ import (
 type testFn func() (bool, error)
 type errorFn func(error)
 
-func WaitForResult(test testFn, error errorFn) {
-	for retries := 100; retries > 0; retries-- {
-		time.Sleep(100 * time.Millisecond)
+const (
+	baseWait = 1 * time.Millisecond
+	maxWait  = 100 * time.Millisecond
+)
 
-		success, err := test()
+func WaitForResult(try testFn, fail errorFn) {
+	var err error
+	wait := baseWait
+	for retries := 100; retries > 0; retries-- {
+		var success bool
+		success, err = try()
 		if success {
 			return
 		}
 
-		if retries == 0 {
-			error(err)
+		time.Sleep(wait)
+		wait *= 2
+		if wait > maxWait {
+			wait = maxWait
 		}
 	}
+	fail(err)
 }
 
 type rpcFn func(string, interface{}, interface{}) error