functional-tester: don't specify data dir on tester side

Data directory is added automatially in commit 2e3d27e but test was
not updated.

tools/functional-tester/etcd-agent/agent_test.go

@@ -15,7 +15,6 @@
 package main
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"syscall"
@@ -27,10 +26,10 @@ var etcdPath = filepath.Join(os.Getenv("GOPATH"), "bin/etcd")
 func TestAgentStart(t *testing.T) {
 	defer os.Remove("etcd.log")
 
-	a, dir := newTestAgent(t)
+	a := newTestAgent(t)
 	defer a.terminate()
 
-	err := a.start("--data-dir", dir)
+	err := a.start()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -39,10 +38,10 @@ func TestAgentStart(t *testing.T) {
 func TestAgentRestart(t *testing.T) {
 	defer os.Remove("etcd.log")
 
-	a, dir := newTestAgent(t)
+	a := newTestAgent(t)
 	defer a.terminate()
 
-	err := a.start("--data-dir", dir)
+	err := a.start()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -60,9 +59,9 @@ func TestAgentRestart(t *testing.T) {
 func TestAgentTerminate(t *testing.T) {
 	defer os.Remove("etcd.log")
 
-	a, dir := newTestAgent(t)
+	a := newTestAgent(t)
 
-	err := a.start("--data-dir", dir)
+	err := a.start()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -72,21 +71,17 @@ func TestAgentTerminate(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if _, err := os.Stat(dir); !os.IsNotExist(err) {
+	if _, err := os.Stat(a.dataDir()); !os.IsNotExist(err) {
 		t.Fatal(err)
 	}
 }
 
-// newTestAgent creates a test agent and with a temp data directory.
-func newTestAgent(t *testing.T) (*Agent, string) {
+// newTestAgent creates a test agent
+func newTestAgent(t *testing.T) *Agent {
 	a, err := newAgent(AgentConfig{EtcdPath: etcdPath, LogDir: "etcd.log"})
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	dir, err := ioutil.TempDir(os.TempDir(), "etcd-agent")
-	if err != nil {
-		t.Fatal(err)
-	}
-	return a, dir
+	return a
 }