*: remove shadowing of variables from etcd and add travis test

We've been bitten by this enough times that I wrote a tool so that
it never happens again.

.travis.yml

@@ -6,6 +6,7 @@ go:
 install:
  - go get golang.org/x/tools/cmd/cover
  - go get golang.org/x/tools/cmd/vet
+ - go get github.com/barakmich/go-nyet
 
 script:
  - INTEGRATION=y ./test

client/keys_test.go

@@ -89,7 +89,7 @@ func TestV2KeysURLHelper(t *testing.T) {
 
 func TestGetAction(t *testing.T) {
 	ep := url.URL{Scheme: "http", Host: "example.com/v2/keys"}
-	wantURL := &url.URL{
+	baseWantURL := &url.URL{
 		Scheme: "http",
 		Host:   "example.com",
 		Path:   "/v2/keys/foo/bar",
@@ -117,7 +117,7 @@ func TestGetAction(t *testing.T) {
 		}
 		got := *f.HTTPRequest(ep)
 
-		wantURL := wantURL
+		wantURL := baseWantURL
 		wantURL.RawQuery = tt.wantQuery
 
 		err := assertResponse(got, wantURL, wantHeader, nil)
@@ -129,7 +129,7 @@ func TestGetAction(t *testing.T) {
 
 func TestWaitAction(t *testing.T) {
 	ep := url.URL{Scheme: "http", Host: "example.com/v2/keys"}
-	wantURL := &url.URL{
+	baseWantURL := &url.URL{
 		Scheme: "http",
 		Host:   "example.com",
 		Path:   "/v2/keys/foo/bar",
@@ -166,7 +166,7 @@ func TestWaitAction(t *testing.T) {
 		}
 		got := *f.HTTPRequest(ep)
 
-		wantURL := wantURL
+		wantURL := baseWantURL
 		wantURL.RawQuery = tt.wantQuery
 
 		err := assertResponse(got, wantURL, wantHeader, nil)

discovery/discovery_test.go

@@ -193,14 +193,14 @@ func TestCheckCluster(t *testing.T) {
 			})
 		}
 		c := &clientWithResp{rs: rs}
-		d := discovery{cluster: cluster, id: 1, c: c}
+		dBase := discovery{cluster: cluster, id: 1, c: c}
 
 		cRetry := &clientWithRetry{failTimes: 3}
 		cRetry.rs = rs
 		fc := clockwork.NewFakeClock()
 		dRetry := discovery{cluster: cluster, id: 1, c: cRetry, clock: fc}
 
-		for _, d := range []discovery{d, dRetry} {
+		for _, d := range []discovery{dBase, dRetry} {
 			go func() {
 				for i := uint(1); i <= maxRetryInTest; i++ {
 					fc.BlockUntil(1)
@@ -263,7 +263,7 @@ func TestWaitNodes(t *testing.T) {
 	for i, tt := range tests {
 		// Basic case
 		c := &clientWithResp{nil, &watcherWithResp{tt.rs}}
-		d := &discovery{cluster: "1000", c: c}
+		dBase := &discovery{cluster: "1000", c: c}
 
 		// Retry case
 		retryScanResp := make([]*client.Response, 0)
@@ -291,7 +291,7 @@ func TestWaitNodes(t *testing.T) {
 			clock:   fc,
 		}
 
-		for _, d := range []*discovery{d, dRetry} {
+		for _, d := range []*discovery{dBase, dRetry} {
 			go func() {
 				for i := uint(1); i <= maxRetryInTest; i++ {
 					fc.BlockUntil(1)

etcdctl/command/member_commands.go

@@ -134,10 +134,10 @@ func actionMemberAdd(c *cli.Context) {
 	}
 
 	conf := []string{}
-	for _, m := range members {
-		for _, u := range m.PeerURLs {
-			n := m.Name
-			if m.ID == newID {
+	for _, memb := range members {
+		for _, u := range memb.PeerURLs {
+			n := memb.Name
+			if memb.ID == newID {
 				n = newName
 			}
 			conf = append(conf, fmt.Sprintf("%s=%s", n, u))
@@ -160,8 +160,9 @@ func actionMemberRemove(c *cli.Context) {
 
 	mAPI := mustNewMembersAPI(c)
 	// Get the list of members.
-	listctx, cancel := context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
+	listctx, listCancel := context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
 	members, err := mAPI.List(listctx)
+	listCancel()
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "Error while verifying ID against known members:", err.Error())
 		os.Exit(1)
@@ -184,9 +185,9 @@ func actionMemberRemove(c *cli.Context) {
 	}
 
 	// Actually attempt to remove the member.
-	ctx, cancel := context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
+	ctx, removeCancel := context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
 	err = mAPI.Remove(ctx, removalID)
-	cancel()
+	removeCancel()
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Recieved an error trying to remove member %s: %s", removalID, err.Error())
 		os.Exit(1)

etcdserver/etcdhttp/client_test.go

@@ -1064,13 +1064,13 @@ func TestServeMembersFail(t *testing.T) {
 
 func TestWriteEvent(t *testing.T) {
 	// nil event should not panic
-	rw := httptest.NewRecorder()
-	writeKeyEvent(rw, nil, dummyRaftTimer{})
-	h := rw.Header()
+	rec := httptest.NewRecorder()
+	writeKeyEvent(rec, nil, dummyRaftTimer{})
+	h := rec.Header()
 	if len(h) > 0 {
 		t.Fatalf("unexpected non-empty headers: %#v", h)
 	}
-	b := rw.Body.String()
+	b := rec.Body.String()
 	if len(b) > 0 {
 		t.Fatalf("unexpected non-empty body: %q", b)
 	}

etcdserver/etcdhttp/http_test.go

@@ -76,13 +76,13 @@ func (fs *errServer) UpdateMember(ctx context.Context, m etcdserver.Member) erro
 
 func TestWriteError(t *testing.T) {
 	// nil error should not panic
-	rw := httptest.NewRecorder()
-	writeError(rw, nil)
-	h := rw.Header()
+	rec := httptest.NewRecorder()
+	writeError(rec, nil)
+	h := rec.Header()
 	if len(h) > 0 {
 		t.Fatalf("unexpected non-empty headers: %#v", h)
 	}
-	b := rw.Body.String()
+	b := rec.Body.String()
 	if len(b) > 0 {
 		t.Fatalf("unexpected non-empty body: %q", b)
 	}

etcdserver/server.go

@@ -177,11 +177,11 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 			return nil, fmt.Errorf("member %s has already been bootstrapped", m.ID)
 		}
 		if cfg.ShouldDiscover() {
-			s, err := discovery.JoinCluster(cfg.DiscoveryURL, cfg.DiscoveryProxy, m.ID, cfg.Cluster.String())
+			str, err := discovery.JoinCluster(cfg.DiscoveryURL, cfg.DiscoveryProxy, m.ID, cfg.Cluster.String())
 			if err != nil {
 				return nil, err
 			}
-			if cfg.Cluster, err = NewClusterFromString(cfg.Cluster.token, s); err != nil {
+			if cfg.Cluster, err = NewClusterFromString(cfg.Cluster.token, str); err != nil {
 				return nil, err
 			}
 			if err := cfg.Cluster.Validate(); err != nil {

etcdserver/server_test.go

@@ -1027,8 +1027,8 @@ func TestPublish(t *testing.T) {
 		t.Errorf("method = %s, want PUT", r.Method)
 	}
 	wm := Member{ID: 1, Attributes: Attributes{Name: "node1", ClientURLs: []string{"http://a", "http://b"}}}
-	if w := path.Join(memberStoreKey(wm.ID), attributesSuffix); r.Path != w {
-		t.Errorf("path = %s, want %s", r.Path, w)
+	if wpath := path.Join(memberStoreKey(wm.ID), attributesSuffix); r.Path != wpath {
+		t.Errorf("path = %s, want %s", r.Path, wpath)
 	}
 	var gattr Attributes
 	if err := json.Unmarshal([]byte(r.Val), &gattr); err != nil {
@@ -1072,8 +1072,8 @@ func TestPublishRetry(t *testing.T) {
 
 	action := n.Action()
 	// multiple Proposes
-	if n := len(action); n < 2 {
-		t.Errorf("len(action) = %d, want >= 2", n)
+	if cnt := len(action); cnt < 2 {
+		t.Errorf("len(action) = %d, want >= 2", cnt)
 	}
 }
 

integration/cluster_test.go

@@ -186,13 +186,13 @@ func clusterMustProgress(t *testing.T, membs []*member) {
 
 	for i, m := range membs {
 		u := m.URL()
-		cc := mustNewHTTPClient(t, []string{u})
-		kapi := client.NewKeysAPI(cc)
-		ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
-		if _, err := kapi.Watch(key, resp.Node.ModifiedIndex).Next(ctx); err != nil {
+		mcc := mustNewHTTPClient(t, []string{u})
+		mkapi := client.NewKeysAPI(mcc)
+		mctx, mcancel := context.WithTimeout(context.Background(), requestTimeout)
+		if _, err := mkapi.Watch(key, resp.Node.ModifiedIndex).Next(mctx); err != nil {
 			t.Fatalf("#%d: watch on %s error: %v", i, u, err)
 		}
-		cancel()
+		mcancel()
 	}
 }
 

integration/v2_http_kv_test.go

@@ -327,21 +327,21 @@ func TestV2Delete(t *testing.T) {
 
 	v := url.Values{}
 	v.Set("value", "XXX")
-	resp, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo"), v)
+	r, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
-	resp, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/emptydir?dir=true"), v)
+	r.Body.Close()
+	r, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/emptydir?dir=true"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
-	resp, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foodir/bar?dir=true"), v)
+	r.Body.Close()
+	r, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foodir/bar?dir=true"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
+	r.Body.Close()
 
 	tests := []struct {
 		relativeURL string
@@ -423,17 +423,17 @@ func TestV2CAD(t *testing.T) {
 
 	v := url.Values{}
 	v.Set("value", "XXX")
-	resp, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo"), v)
+	r, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
+	r.Body.Close()
 
-	resp, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foovalue"), v)
+	r, err = tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foovalue"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
+	r.Body.Close()
 
 	tests := []struct {
 		relativeURL string
@@ -582,11 +582,11 @@ func TestV2Get(t *testing.T) {
 
 	v := url.Values{}
 	v.Set("value", "XXX")
-	resp, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo/bar/zar"), v)
+	r, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo/bar/zar"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
+	r.Body.Close()
 
 	tests := []struct {
 		relativeURL string
@@ -676,11 +676,11 @@ func TestV2QuorumGet(t *testing.T) {
 
 	v := url.Values{}
 	v.Set("value", "XXX")
-	resp, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo/bar/zar?quorum=true"), v)
+	r, err := tc.PutForm(fmt.Sprintf("%s%s", u, "/v2/keys/foo/bar/zar?quorum=true"), v)
 	if err != nil {
 		t.Error(err)
 	}
-	resp.Body.Close()
+	r.Body.Close()
 
 	tests := []struct {
 		relativeURL string

migrate/etcd4.go

@@ -175,8 +175,8 @@ func GuessNodeID(nodes map[string]uint64, snap4 *Snapshot4, cfg *Config4, name s
 			delete(snapNodes, p.Name)
 		}
 		if len(snapNodes) == 1 {
-			for name, id := range nodes {
-				log.Printf("Autodetected from snapshot: name %s", name)
+			for nodename, id := range nodes {
+				log.Printf("Autodetected from snapshot: name %s", nodename)
 				return id
 			}
 		}
@@ -186,8 +186,8 @@ func GuessNodeID(nodes map[string]uint64, snap4 *Snapshot4, cfg *Config4, name s
 		delete(nodes, p.Name)
 	}
 	if len(nodes) == 1 {
-		for name, id := range nodes {
-			log.Printf("Autodetected name %s", name)
+		for nodename, id := range nodes {
+			log.Printf("Autodetected name %s", nodename)
 			return id
 		}
 	}

migrate/starter/starter.go

@@ -106,12 +106,12 @@ func checkInternalVersion(fs *flag.FlagSet) version {
 		log.Fatalf("starter: please set --data-dir or ETCD_DATA_DIR for etcd")
 	}
 	// check the data directory
-	ver, err := checkVersion(dataDir)
+	dataver, err := checkVersion(dataDir)
 	if err != nil {
 		log.Fatalf("starter: failed to detect etcd version in %v: %v", dataDir, err)
 	}
-	log.Printf("starter: detect etcd version %s in %s", ver, dataDir)
-	switch ver {
+	log.Printf("starter: detect etcd version %s in %s", dataver, dataDir)
+	switch dataver {
 	case v2_0:
 		return internalV2
 	case v2_0Proxy:

raft/log_test.go

@@ -296,15 +296,15 @@ func TestCompactionSideEffects(t *testing.T) {
 		t.Errorf("lastIndex = %d, want %d", raftLog.lastIndex(), lastIndex)
 	}
 
-	for i := offset; i <= raftLog.lastIndex(); i++ {
-		if raftLog.term(i) != i {
-			t.Errorf("term(%d) = %d, want %d", i, raftLog.term(i), i)
+	for j := offset; j <= raftLog.lastIndex(); j++ {
+		if raftLog.term(j) != j {
+			t.Errorf("term(%d) = %d, want %d", j, raftLog.term(j), j)
 		}
 	}
 
-	for i := offset; i <= raftLog.lastIndex(); i++ {
-		if !raftLog.matchTerm(i, i) {
-			t.Errorf("matchTerm(%d) = false, want true", i)
+	for j := offset; j <= raftLog.lastIndex(); j++ {
+		if !raftLog.matchTerm(j, j) {
+			t.Errorf("matchTerm(%d) = false, want true", j)
 		}
 	}
 
@@ -354,9 +354,9 @@ func TestNextEnts(t *testing.T) {
 		raftLog.maybeCommit(5, 1)
 		raftLog.appliedTo(tt.applied)
 
-		ents := raftLog.nextEnts()
-		if !reflect.DeepEqual(ents, tt.wents) {
-			t.Errorf("#%d: ents = %+v, want %+v", i, ents, tt.wents)
+		nents := raftLog.nextEnts()
+		if !reflect.DeepEqual(nents, tt.wents) {
+			t.Errorf("#%d: nents = %+v, want %+v", i, nents, tt.wents)
 		}
 	}
 }
@@ -649,10 +649,10 @@ func TestTerm(t *testing.T) {
 		{offset + num, 0},
 	}
 
-	for i, tt := range tests {
+	for j, tt := range tests {
 		term := l.term(tt.index)
 		if !reflect.DeepEqual(term, tt.w) {
-			t.Errorf("#%d: at = %d, want %d", i, term, tt.w)
+			t.Errorf("#%d: at = %d, want %d", j, term, tt.w)
 		}
 	}
 }
@@ -712,18 +712,18 @@ func TestSlice(t *testing.T) {
 		{offset + num, offset + num + 1, nil, true},
 	}
 
-	for i, tt := range tests {
+	for j, tt := range tests {
 		func() {
 			defer func() {
 				if r := recover(); r != nil {
 					if !tt.wpanic {
-						t.Errorf("%d: panic = %v, want %v: %v", i, true, false, r)
+						t.Errorf("%d: panic = %v, want %v: %v", j, true, false, r)
 					}
 				}
 			}()
 			g := l.slice(tt.from, tt.to)
 			if !reflect.DeepEqual(g, tt.w) {
-				t.Errorf("#%d: from %d to %d = %v, want %v", i, tt.from, tt.to, g, tt.w)
+				t.Errorf("#%d: from %d to %d = %v, want %v", j, tt.from, tt.to, g, tt.w)
 			}
 		}()
 	}

raft/node_test.go

@@ -332,10 +332,10 @@ func TestNodeStart(t *testing.T) {
 	}
 
 	n.Propose(ctx, []byte("foo"))
-	if g := <-n.Ready(); !reflect.DeepEqual(g, wants[1]) {
-		t.Errorf("#%d: g = %+v,\n             w   %+v", 2, g, wants[1])
+	if g2 := <-n.Ready(); !reflect.DeepEqual(g2, wants[1]) {
+		t.Errorf("#%d: g = %+v,\n             w   %+v", 2, g2, wants[1])
 	} else {
-		storage.Append(g.Entries)
+		storage.Append(g2.Entries)
 		n.Advance()
 	}
 

raft/raft_paper_test.go

@@ -774,7 +774,7 @@ func TestVoteRequest(t *testing.T) {
 		{[]pb.Entry{{Term: 1, Index: 1}}, 2},
 		{[]pb.Entry{{Term: 1, Index: 1}, {Term: 2, Index: 2}}, 3},
 	}
-	for i, tt := range tests {
+	for j, tt := range tests {
 		r := newRaft(1, []uint64{1, 2, 3}, 10, 1, NewMemoryStorage(), 0)
 		r.Step(pb.Message{
 			From: 2, To: 1, Type: pb.MsgApp, Term: tt.wterm - 1, LogTerm: 0, Index: 0, Entries: tt.ents,
@@ -788,7 +788,7 @@ func TestVoteRequest(t *testing.T) {
 		msgs := r.readMessages()
 		sort.Sort(messageSlice(msgs))
 		if len(msgs) != 2 {
-			t.Fatalf("#%d: len(msg) = %d, want %d", i, len(msgs), 2)
+			t.Fatalf("#%d: len(msg) = %d, want %d", j, len(msgs), 2)
 		}
 		for i, m := range msgs {
 			if m.Type != pb.MsgVote {

raft/raft_test.go

@@ -510,7 +510,7 @@ func TestOldMessages(t *testing.T) {
 	// commit a new entry
 	tt.send(pb.Message{From: 1, To: 1, Type: pb.MsgProp, Entries: []pb.Entry{{Data: []byte("somedata")}}})
 
-	l := &raftLog{
+	ilog := &raftLog{
 		storage: &MemoryStorage{
 			ents: []pb.Entry{
 				{}, {Data: nil, Term: 1, Index: 1},
@@ -521,7 +521,7 @@ func TestOldMessages(t *testing.T) {
 		unstable:  unstable{offset: 5},
 		committed: 4,
 	}
-	base := ltoa(l)
+	base := ltoa(ilog)
 	for i, p := range tt.peers {
 		if sm, ok := p.(*raft); ok {
 			l := ltoa(sm.raftLog)
@@ -548,7 +548,7 @@ func TestProposal(t *testing.T) {
 		{newNetwork(nil, nopStepper, nopStepper, nil, nil), true},
 	}
 
-	for i, tt := range tests {
+	for j, tt := range tests {
 		send := func(m pb.Message) {
 			defer func() {
 				// only recover is we expect it to panic so
@@ -556,7 +556,7 @@ func TestProposal(t *testing.T) {
 				if !tt.success {
 					e := recover()
 					if e != nil {
-						t.Logf("#%d: err: %s", i, e)
+						t.Logf("#%d: err: %s", j, e)
 					}
 				}
 			}()
@@ -591,7 +591,7 @@ func TestProposal(t *testing.T) {
 		}
 		sm := tt.network.peers[1].(*raft)
 		if g := sm.Term; g != 1 {
-			t.Errorf("#%d: term = %d, want %d", i, g, 1)
+			t.Errorf("#%d: term = %d, want %d", j, g, 1)
 		}
 	}
 }
@@ -603,7 +603,7 @@ func TestProposalByProxy(t *testing.T) {
 		newNetwork(nil, nil, nopStepper),
 	}
 
-	for i, tt := range tests {
+	for j, tt := range tests {
 		// promote 0 the leader
 		tt.send(pb.Message{From: 1, To: 1, Type: pb.MsgHup})
 
@@ -629,7 +629,7 @@ func TestProposalByProxy(t *testing.T) {
 		}
 		sm := tt.peers[1].(*raft)
 		if g := sm.Term; g != 1 {
-			t.Errorf("#%d: term = %d, want %d", i, g, 1)
+			t.Errorf("#%d: term = %d, want %d", j, g, 1)
 		}
 	}
 }
@@ -1601,8 +1601,8 @@ func newNetwork(peers ...Interface) *network {
 	npeers := make(map[uint64]Interface, size)
 	nstorage := make(map[uint64]*MemoryStorage, size)
 
-	for i, p := range peers {
-		id := peerAddrs[i]
+	for j, p := range peers {
+		id := peerAddrs[j]
 		switch v := p.(type) {
 		case nil:
 			nstorage[id] = NewMemoryStorage()

store/event_test.go

@@ -88,8 +88,8 @@ func TestFullEventQueue(t *testing.T) {
 
 	// Add
 	for i := 0; i < 1000; i++ {
-		e := newEvent(Create, "/foo", uint64(i), uint64(i))
-		eh.addEvent(e)
+		ce := newEvent(Create, "/foo", uint64(i), uint64(i))
+		eh.addEvent(ce)
 		e, err := eh.scan("/foo", true, uint64(i-1))
 		if i > 0 {
 			if e == nil || err != nil {

store/heap_test.go

@@ -51,10 +51,10 @@ func TestHeapUpdate(t *testing.T) {
 
 	// add from older expire time to earlier expire time
 	// the path is equal to ttl from now
-	for i, n := range kvs {
+	for i := range kvs {
 		path := fmt.Sprintf("%v", 10-i)
 		m := time.Duration(10 - i)
-		n = newKV(nil, path, path, 0, nil, "", time.Now().Add(time.Second*m))
+		n := newKV(nil, path, path, 0, nil, "", time.Now().Add(time.Second*m))
 		kvs[i] = n
 		h.push(n)
 	}

test

@@ -60,4 +60,13 @@ if [ -n "${vetRes}" ]; then
 	exit 255
 fi
 
+if [ -f `which go-nyet` ]; then
+  echo "Checking go-nyet..."
+  nyetRes=$(go-nyet -exitWith 0 $FMT)
+  if [ -n "${nyetRes}" ]; then
+          echo -e "go-nyet checking failed:\n${nyetRes}"
+          exit 255
+  fi
+fi
+
 echo "Success"

wal/wal_test.go

@@ -323,23 +323,23 @@ func TestRecoverAfterCut(t *testing.T) {
 	}
 	defer os.RemoveAll(p)
 
-	w, err := Create(p, []byte("metadata"))
+	md, err := Create(p, []byte("metadata"))
 	if err != nil {
 		t.Fatal(err)
 	}
 	for i := 0; i < 10; i++ {
-		if err = w.SaveSnapshot(walpb.Snapshot{Index: uint64(i)}); err != nil {
+		if err = md.SaveSnapshot(walpb.Snapshot{Index: uint64(i)}); err != nil {
 			t.Fatal(err)
 		}
 		es := []raftpb.Entry{{Index: uint64(i)}}
-		if err = w.Save(raftpb.HardState{}, es); err != nil {
+		if err = md.Save(raftpb.HardState{}, es); err != nil {
 			t.Fatal(err)
 		}
-		if err = w.Cut(); err != nil {
+		if err = md.Cut(); err != nil {
 			t.Fatal(err)
 		}
 	}
-	w.Close()
+	md.Close()
 
 	if err := os.Remove(path.Join(p, walName(4, 4))); err != nil {
 		t.Fatal(err)