Imported Upstream version 1.1~hg20130304upstream/1.1_hg20130304

1 files changed, 558 insertions, 19 deletions

diff --git a/src/pkg/net/http/transport_test.go b/src/pkg/net/http/transport_test.go
index a9e401de5..68010e68b 100644
--- a/src/pkg/net/http/transport_test.go
+++ b/src/pkg/net/http/transport_test.go
@@ -13,6 +13,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"net"
 	. "net/http"
 	"net/http/httptest"
 	"net/url"
@@ -20,6 +21,7 @@ import (
 	"runtime"
 	"strconv"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 )
@@ -35,14 +37,78 @@ var hostPortHandler = HandlerFunc(func(w ResponseWriter, r *Request) {
 	w.Write([]byte(r.RemoteAddr))
 })
 
+// testCloseConn is a net.Conn tracked by a testConnSet.
+type testCloseConn struct {
+	net.Conn
+	set *testConnSet
+}
+
+func (c *testCloseConn) Close() error {
+	c.set.remove(c)
+	return c.Conn.Close()
+}
+
+// testConnSet tracks a set of TCP connections and whether they've
+// been closed.
+type testConnSet struct {
+	t      *testing.T
+	closed map[net.Conn]bool
+	list   []net.Conn // in order created
+	mutex  sync.Mutex
+}
+
+func (tcs *testConnSet) insert(c net.Conn) {
+	tcs.mutex.Lock()
+	defer tcs.mutex.Unlock()
+	tcs.closed[c] = false
+	tcs.list = append(tcs.list, c)
+}
+
+func (tcs *testConnSet) remove(c net.Conn) {
+	tcs.mutex.Lock()
+	defer tcs.mutex.Unlock()
+	tcs.closed[c] = true
+}
+
+// some tests use this to manage raw tcp connections for later inspection
+func makeTestDial(t *testing.T) (*testConnSet, func(n, addr string) (net.Conn, error)) {
+	connSet := &testConnSet{
+		t:      t,
+		closed: make(map[net.Conn]bool),
+	}
+	dial := func(n, addr string) (net.Conn, error) {
+		c, err := net.Dial(n, addr)
+		if err != nil {
+			return nil, err
+		}
+		tc := &testCloseConn{c, connSet}
+		connSet.insert(tc)
+		return tc, nil
+	}
+	return connSet, dial
+}
+
+func (tcs *testConnSet) check(t *testing.T) {
+	tcs.mutex.Lock()
+	defer tcs.mutex.Unlock()
+
+	for i, c := range tcs.list {
+		if !tcs.closed[c] {
+			t.Errorf("TCP connection #%d, %p (of %d total) was not closed", i+1, c, len(tcs.list))
+		}
+	}
+}
+
 // Two subsequent requests and verify their response is the same.
 // The response from the server is our own IP:port
 func TestTransportKeepAlives(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
 	for _, disableKeepAlive := range []bool{false, true} {
 		tr := &Transport{DisableKeepAlives: disableKeepAlive}
+		defer tr.CloseIdleConnections()
 		c := &Client{Transport: tr}
 
 		fetch := func(n int) string {
@@ -69,11 +135,16 @@ func TestTransportKeepAlives(t *testing.T) {
 }
 
 func TestTransportConnectionCloseOnResponse(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
+	connSet, testDial := makeTestDial(t)
+
 	for _, connectionClose := range []bool{false, true} {
-		tr := &Transport{}
+		tr := &Transport{
+			Dial: testDial,
+		}
 		c := &Client{Transport: tr}
 
 		fetch := func(n int) string {
@@ -92,8 +163,8 @@ func TestTransportConnectionCloseOnResponse(t *testing.T) {
 			if err != nil {
 				t.Fatalf("error in connectionClose=%v, req #%d, Do: %v", connectionClose, n, err)
 			}
-			body, err := ioutil.ReadAll(res.Body)
 			defer res.Body.Close()
+			body, err := ioutil.ReadAll(res.Body)
 			if err != nil {
 				t.Fatalf("error in connectionClose=%v, req #%d, ReadAll: %v", connectionClose, n, err)
 			}
@@ -107,15 +178,24 @@ func TestTransportConnectionCloseOnResponse(t *testing.T) {
 			t.Errorf("error in connectionClose=%v. unexpected bodiesDiffer=%v; body1=%q; body2=%q",
 				connectionClose, bodiesDiffer, body1, body2)
 		}
+
+		tr.CloseIdleConnections()
 	}
+
+	connSet.check(t)
 }
 
 func TestTransportConnectionCloseOnRequest(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
+	connSet, testDial := makeTestDial(t)
+
 	for _, connectionClose := range []bool{false, true} {
-		tr := &Transport{}
+		tr := &Transport{
+			Dial: testDial,
+		}
 		c := &Client{Transport: tr}
 
 		fetch := func(n int) string {
@@ -149,10 +229,15 @@ func TestTransportConnectionCloseOnRequest(t *testing.T) {
 			t.Errorf("error in connectionClose=%v. unexpected bodiesDiffer=%v; body1=%q; body2=%q",
 				connectionClose, bodiesDiffer, body1, body2)
 		}
+
+		tr.CloseIdleConnections()
 	}
+
+	connSet.check(t)
 }
 
 func TestTransportIdleCacheKeys(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
@@ -185,6 +270,7 @@ func TestTransportIdleCacheKeys(t *testing.T) {
 }
 
 func TestTransportMaxPerHostIdleConns(t *testing.T) {
+	defer checkLeakedTransports(t)
 	resch := make(chan string)
 	gotReq := make(chan bool)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
@@ -201,7 +287,7 @@ func TestTransportMaxPerHostIdleConns(t *testing.T) {
 	c := &Client{Transport: tr}
 
 	// Start 3 outstanding requests and wait for the server to get them.
-	// Their responses will hang until we we write to resch, though.
+	// Their responses will hang until we write to resch, though.
 	donech := make(chan bool)
 	doReq := func() {
 		resp, err := c.Get(ts.URL)
@@ -253,6 +339,7 @@ func TestTransportMaxPerHostIdleConns(t *testing.T) {
 }
 
 func TestTransportServerClosingUnexpectedly(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
@@ -309,9 +396,9 @@ func TestTransportServerClosingUnexpectedly(t *testing.T) {
 // Test for http://golang.org/issue/2616 (appropriate issue number)
 // This fails pretty reliably with GOMAXPROCS=100 or something high.
 func TestStressSurpriseServerCloses(t *testing.T) {
+	defer checkLeakedTransports(t)
 	if testing.Short() {
-		t.Logf("skipping test in short mode")
-		return
+		t.Skip("skipping test in short mode")
 	}
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		w.Header().Set("Content-Length", "5")
@@ -365,6 +452,7 @@ func TestStressSurpriseServerCloses(t *testing.T) {
 // TestTransportHeadResponses verifies that we deal with Content-Lengths
 // with no bodies properly
 func TestTransportHeadResponses(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		if r.Method != "HEAD" {
 			panic("expected HEAD; got " + r.Method)
@@ -384,7 +472,7 @@ func TestTransportHeadResponses(t *testing.T) {
 		if e, g := "123", res.Header.Get("Content-Length"); e != g {
 			t.Errorf("loop %d: expected Content-Length header of %q, got %q", i, e, g)
 		}
-		if e, g := int64(0), res.ContentLength; e != g {
+		if e, g := int64(123), res.ContentLength; e != g {
 			t.Errorf("loop %d: expected res.ContentLength of %v, got %v", i, e, g)
 		}
 	}
@@ -393,6 +481,7 @@ func TestTransportHeadResponses(t *testing.T) {
 // TestTransportHeadChunkedResponse verifies that we ignore chunked transfer-encoding
 // on responses to HEAD requests.
 func TestTransportHeadChunkedResponse(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		if r.Method != "HEAD" {
 			panic("expected HEAD; got " + r.Method)
@@ -434,6 +523,7 @@ var roundTripTests = []struct {
 
 // Test that the modification made to the Request by the RoundTripper is cleaned up
 func TestRoundTripGzip(t *testing.T) {
+	defer checkLeakedTransports(t)
 	const responseBody = "test response body"
 	ts := httptest.NewServer(HandlerFunc(func(rw ResponseWriter, req *Request) {
 		accept := req.Header.Get("Accept-Encoding")
@@ -490,6 +580,7 @@ func TestRoundTripGzip(t *testing.T) {
 }
 
 func TestTransportGzip(t *testing.T) {
+	defer checkLeakedTransports(t)
 	const testString = "The test string aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
 	const nRandBytes = 1024 * 1024
 	ts := httptest.NewServer(HandlerFunc(func(rw ResponseWriter, req *Request) {
@@ -582,6 +673,7 @@ func TestTransportGzip(t *testing.T) {
 }
 
 func TestTransportProxy(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ch := make(chan string, 1)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		ch <- "real server"
@@ -610,6 +702,7 @@ func TestTransportProxy(t *testing.T) {
 // but checks that we don't recurse forever, and checks that
 // Content-Encoding is removed.
 func TestTransportGzipRecursive(t *testing.T) {
+	defer checkLeakedTransports(t)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		w.Header().Set("Content-Encoding", "gzip")
 		w.Write(rgz)
@@ -636,6 +729,7 @@ func TestTransportGzipRecursive(t *testing.T) {
 
 // tests that persistent goroutine connections shut down when no longer desired.
 func TestTransportPersistConnLeak(t *testing.T) {
+	defer checkLeakedTransports(t)
 	gotReqCh := make(chan bool)
 	unblockCh := make(chan bool)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
@@ -698,8 +792,49 @@ func TestTransportPersistConnLeak(t *testing.T) {
 	}
 }
 
+// golang.org/issue/4531: Transport leaks goroutines when
+// request.ContentLength is explicitly short
+func TestTransportPersistConnLeakShortBody(t *testing.T) {
+	defer checkLeakedTransports(t)
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+	}))
+	defer ts.Close()
+
+	tr := &Transport{}
+	c := &Client{Transport: tr}
+
+	n0 := runtime.NumGoroutine()
+	body := []byte("Hello")
+	for i := 0; i < 20; i++ {
+		req, err := NewRequest("POST", ts.URL, bytes.NewReader(body))
+		if err != nil {
+			t.Fatal(err)
+		}
+		req.ContentLength = int64(len(body) - 2) // explicitly short
+		_, err = c.Do(req)
+		if err == nil {
+			t.Fatal("Expect an error from writing too long of a body.")
+		}
+	}
+	nhigh := runtime.NumGoroutine()
+	tr.CloseIdleConnections()
+	time.Sleep(50 * time.Millisecond)
+	runtime.GC()
+	nfinal := runtime.NumGoroutine()
+
+	growth := nfinal - n0
+
+	// We expect 0 or 1 extra goroutine, empirically.  Allow up to 5.
+	// Previously we were leaking one per numReq.
+	t.Logf("goroutine growth: %d -> %d -> %d (delta: %d)", n0, nhigh, nfinal, growth)
+	if int(growth) > 5 {
+		t.Error("too many new goroutines")
+	}
+}
+
 // This used to crash; http://golang.org/issue/3266
 func TestTransportIdleConnCrash(t *testing.T) {
+	defer checkLeakedTransports(t)
 	tr := &Transport{}
 	c := &Client{Transport: tr}
 
@@ -724,6 +859,361 @@ func TestTransportIdleConnCrash(t *testing.T) {
 	<-didreq
 }
 
+// Test that the transport doesn't close the TCP connection early,
+// before the response body has been read.  This was a regression
+// which sadly lacked a triggering test.  The large response body made
+// the old race easier to trigger.
+func TestIssue3644(t *testing.T) {
+	defer checkLeakedTransports(t)
+	const numFoos = 5000
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		w.Header().Set("Connection", "close")
+		for i := 0; i < numFoos; i++ {
+			w.Write([]byte("foo "))
+		}
+	}))
+	defer ts.Close()
+	tr := &Transport{}
+	c := &Client{Transport: tr}
+	res, err := c.Get(ts.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer res.Body.Close()
+	bs, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(bs) != numFoos*len("foo ") {
+		t.Errorf("unexpected response length")
+	}
+}
+
+// Test that a client receives a server's reply, even if the server doesn't read
+// the entire request body.
+func TestIssue3595(t *testing.T) {
+	defer checkLeakedTransports(t)
+	const deniedMsg = "sorry, denied."
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		Error(w, deniedMsg, StatusUnauthorized)
+	}))
+	defer ts.Close()
+	tr := &Transport{}
+	c := &Client{Transport: tr}
+	res, err := c.Post(ts.URL, "application/octet-stream", neverEnding('a'))
+	if err != nil {
+		t.Errorf("Post: %v", err)
+		return
+	}
+	got, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		t.Fatalf("Body ReadAll: %v", err)
+	}
+	if !strings.Contains(string(got), deniedMsg) {
+		t.Errorf("Known bug: response %q does not contain %q", got, deniedMsg)
+	}
+}
+
+// From http://golang.org/issue/4454 ,
+// "client fails to handle requests with no body and chunked encoding"
+func TestChunkedNoContent(t *testing.T) {
+	defer checkLeakedTransports(t)
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		w.WriteHeader(StatusNoContent)
+	}))
+	defer ts.Close()
+
+	for _, closeBody := range []bool{true, false} {
+		c := &Client{Transport: &Transport{}}
+		const n = 4
+		for i := 1; i <= n; i++ {
+			res, err := c.Get(ts.URL)
+			if err != nil {
+				t.Errorf("closingBody=%v, req %d/%d: %v", closeBody, i, n, err)
+			} else {
+				if closeBody {
+					res.Body.Close()
+				}
+			}
+		}
+	}
+}
+
+func TestTransportConcurrency(t *testing.T) {
+	defer checkLeakedTransports(t)
+	const maxProcs = 16
+	const numReqs = 500
+	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(maxProcs))
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		fmt.Fprintf(w, "%v", r.FormValue("echo"))
+	}))
+	defer ts.Close()
+	tr := &Transport{}
+	c := &Client{Transport: tr}
+	reqs := make(chan string)
+	defer close(reqs)
+
+	var wg sync.WaitGroup
+	wg.Add(numReqs)
+	for i := 0; i < maxProcs*2; i++ {
+		go func() {
+			for req := range reqs {
+				res, err := c.Get(ts.URL + "/?echo=" + req)
+				if err != nil {
+					t.Errorf("error on req %s: %v", req, err)
+					wg.Done()
+					continue
+				}
+				all, err := ioutil.ReadAll(res.Body)
+				if err != nil {
+					t.Errorf("read error on req %s: %v", req, err)
+					wg.Done()
+					continue
+				}
+				if string(all) != req {
+					t.Errorf("body of req %s = %q; want %q", req, all, req)
+				}
+				wg.Done()
+				res.Body.Close()
+			}
+		}()
+	}
+	for i := 0; i < numReqs; i++ {
+		reqs <- fmt.Sprintf("request-%d", i)
+	}
+	wg.Wait()
+}
+
+func TestIssue4191_InfiniteGetTimeout(t *testing.T) {
+	defer checkLeakedTransports(t)
+	const debug = false
+	mux := NewServeMux()
+	mux.HandleFunc("/get", func(w ResponseWriter, r *Request) {
+		io.Copy(w, neverEnding('a'))
+	})
+	ts := httptest.NewServer(mux)
+	timeout := 100 * time.Millisecond
+
+	client := &Client{
+		Transport: &Transport{
+			Dial: func(n, addr string) (net.Conn, error) {
+				conn, err := net.Dial(n, addr)
+				if err != nil {
+					return nil, err
+				}
+				conn.SetDeadline(time.Now().Add(timeout))
+				if debug {
+					conn = NewLoggingConn("client", conn)
+				}
+				return conn, nil
+			},
+			DisableKeepAlives: true,
+		},
+	}
+
+	getFailed := false
+	nRuns := 5
+	if testing.Short() {
+		nRuns = 1
+	}
+	for i := 0; i < nRuns; i++ {
+		if debug {
+			println("run", i+1, "of", nRuns)
+		}
+		sres, err := client.Get(ts.URL + "/get")
+		if err != nil {
+			if !getFailed {
+				// Make the timeout longer, once.
+				getFailed = true
+				t.Logf("increasing timeout")
+				i--
+				timeout *= 10
+				continue
+			}
+			t.Errorf("Error issuing GET: %v", err)
+			break
+		}
+		_, err = io.Copy(ioutil.Discard, sres.Body)
+		if err == nil {
+			t.Errorf("Unexpected successful copy")
+			break
+		}
+	}
+	if debug {
+		println("tests complete; waiting for handlers to finish")
+	}
+	ts.Close()
+}
+
+func TestIssue4191_InfiniteGetToPutTimeout(t *testing.T) {
+	defer checkLeakedTransports(t)
+	const debug = false
+	mux := NewServeMux()
+	mux.HandleFunc("/get", func(w ResponseWriter, r *Request) {
+		io.Copy(w, neverEnding('a'))
+	})
+	mux.HandleFunc("/put", func(w ResponseWriter, r *Request) {
+		defer r.Body.Close()
+		io.Copy(ioutil.Discard, r.Body)
+	})
+	ts := httptest.NewServer(mux)
+	timeout := 100 * time.Millisecond
+
+	client := &Client{
+		Transport: &Transport{
+			Dial: func(n, addr string) (net.Conn, error) {
+				conn, err := net.Dial(n, addr)
+				if err != nil {
+					return nil, err
+				}
+				conn.SetDeadline(time.Now().Add(timeout))
+				if debug {
+					conn = NewLoggingConn("client", conn)
+				}
+				return conn, nil
+			},
+			DisableKeepAlives: true,
+		},
+	}
+
+	getFailed := false
+	nRuns := 5
+	if testing.Short() {
+		nRuns = 1
+	}
+	for i := 0; i < nRuns; i++ {
+		if debug {
+			println("run", i+1, "of", nRuns)
+		}
+		sres, err := client.Get(ts.URL + "/get")
+		if err != nil {
+			if !getFailed {
+				// Make the timeout longer, once.
+				getFailed = true
+				t.Logf("increasing timeout")
+				i--
+				timeout *= 10
+				continue
+			}
+			t.Errorf("Error issuing GET: %v", err)
+			break
+		}
+		req, _ := NewRequest("PUT", ts.URL+"/put", sres.Body)
+		_, err = client.Do(req)
+		if err == nil {
+			sres.Body.Close()
+			t.Errorf("Unexpected successful PUT")
+			break
+		}
+		sres.Body.Close()
+	}
+	if debug {
+		println("tests complete; waiting for handlers to finish")
+	}
+	ts.Close()
+}
+
+func TestTransportResponseHeaderTimeout(t *testing.T) {
+	defer checkLeakedTransports(t)
+	if testing.Short() {
+		t.Skip("skipping timeout test in -short mode")
+	}
+	mux := NewServeMux()
+	mux.HandleFunc("/fast", func(w ResponseWriter, r *Request) {})
+	mux.HandleFunc("/slow", func(w ResponseWriter, r *Request) {
+		time.Sleep(2 * time.Second)
+	})
+	ts := httptest.NewServer(mux)
+	defer ts.Close()
+
+	tr := &Transport{
+		ResponseHeaderTimeout: 500 * time.Millisecond,
+	}
+	defer tr.CloseIdleConnections()
+	c := &Client{Transport: tr}
+
+	tests := []struct {
+		path    string
+		want    int
+		wantErr string
+	}{
+		{path: "/fast", want: 200},
+		{path: "/slow", wantErr: "timeout awaiting response headers"},
+		{path: "/fast", want: 200},
+	}
+	for i, tt := range tests {
+		res, err := c.Get(ts.URL + tt.path)
+		if err != nil {
+			if strings.Contains(err.Error(), tt.wantErr) {
+				continue
+			}
+			t.Errorf("%d. unexpected error: %v", i, err)
+			continue
+		}
+		if tt.wantErr != "" {
+			t.Errorf("%d. no error. expected error: %v", i, tt.wantErr)
+			continue
+		}
+		if res.StatusCode != tt.want {
+			t.Errorf("%d for path %q status = %d; want %d", i, tt.path, res.StatusCode, tt.want)
+		}
+	}
+}
+
+func TestTransportCancelRequest(t *testing.T) {
+	defer checkLeakedTransports(t)
+	if testing.Short() {
+		t.Skip("skipping test in -short mode")
+	}
+	unblockc := make(chan bool)
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		fmt.Fprintf(w, "Hello")
+		w.(Flusher).Flush() // send headers and some body
+		<-unblockc
+	}))
+	defer ts.Close()
+	defer close(unblockc)
+
+	tr := &Transport{}
+	defer tr.CloseIdleConnections()
+	c := &Client{Transport: tr}
+
+	req, _ := NewRequest("GET", ts.URL, nil)
+	res, err := c.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	go func() {
+		time.Sleep(1 * time.Second)
+		tr.CancelRequest(req)
+	}()
+	t0 := time.Now()
+	body, err := ioutil.ReadAll(res.Body)
+	d := time.Since(t0)
+
+	if err == nil {
+		t.Error("expected an error reading the body")
+	}
+	if string(body) != "Hello" {
+		t.Errorf("Body = %q; want Hello", body)
+	}
+	if d < 500*time.Millisecond {
+		t.Errorf("expected ~1 second delay; got %v", d)
+	}
+	// Verify no outstanding requests after readLoop/writeLoop
+	// goroutines shut down.
+	for tries := 3; tries > 0; tries-- {
+		n := tr.NumPendingRequestsForTesting()
+		if n == 0 {
+			break
+		}
+		time.Sleep(100 * time.Millisecond)
+		if tries == 1 {
+			t.Errorf("pending requests = %d; want 0", n)
+		}
+	}
+}
+
 type fooProto struct{}
 
 func (fooProto) RoundTrip(req *Request) (*Response, error) {
@@ -737,6 +1227,7 @@ func (fooProto) RoundTrip(req *Request) (*Response, error) {
 }
 
 func TestTransportAltProto(t *testing.T) {
+	defer checkLeakedTransports(t)
 	tr := &Transport{}
 	c := &Client{Transport: tr}
 	tr.RegisterProtocol("foo", fooProto{})
@@ -754,15 +1245,58 @@ func TestTransportAltProto(t *testing.T) {
 	}
 }
 
-var proxyFromEnvTests = []struct {
+func TestTransportNoHost(t *testing.T) {
+	defer checkLeakedTransports(t)
+	tr := &Transport{}
+	_, err := tr.RoundTrip(&Request{
+		Header: make(Header),
+		URL: &url.URL{
+			Scheme: "http",
+		},
+	})
+	want := "http: no Host in request URL"
+	if got := fmt.Sprint(err); got != want {
+		t.Errorf("error = %v; want %q", err, want)
+	}
+}
+
+type proxyFromEnvTest struct {
+	req     string // URL to fetch; blank means "http://example.com"
 	env     string
-	wanturl string
+	noenv   string
+	want    string
 	wanterr error
-}{
-	{"127.0.0.1:8080", "http://127.0.0.1:8080", nil},
-	{"http://127.0.0.1:8080", "http://127.0.0.1:8080", nil},
-	{"https://127.0.0.1:8080", "https://127.0.0.1:8080", nil},
-	{"", "<nil>", nil},
+}
+
+func (t proxyFromEnvTest) String() string {
+	var buf bytes.Buffer
+	if t.env != "" {
+		fmt.Fprintf(&buf, "http_proxy=%q", t.env)
+	}
+	if t.noenv != "" {
+		fmt.Fprintf(&buf, " no_proxy=%q", t.noenv)
+	}
+	req := "http://example.com"
+	if t.req != "" {
+		req = t.req
+	}
+	fmt.Fprintf(&buf, " req=%q", req)
+	return strings.TrimSpace(buf.String())
+}
+
+var proxyFromEnvTests = []proxyFromEnvTest{
+	{env: "127.0.0.1:8080", want: "http://127.0.0.1:8080"},
+	{env: "cache.corp.example.com:1234", want: "http://cache.corp.example.com:1234"},
+	{env: "cache.corp.example.com", want: "http://cache.corp.example.com"},
+	{env: "https://cache.corp.example.com", want: "https://cache.corp.example.com"},
+	{env: "http://127.0.0.1:8080", want: "http://127.0.0.1:8080"},
+	{env: "https://127.0.0.1:8080", want: "https://127.0.0.1:8080"},
+	{want: "<nil>"},
+	{noenv: "example.com", req: "http://example.com/", env: "proxy", want: "<nil>"},
+	{noenv: ".example.com", req: "http://example.com/", env: "proxy", want: "<nil>"},
+	{noenv: "ample.com", req: "http://example.com/", env: "proxy", want: "http://proxy"},
+	{noenv: "example.com", req: "http://foo.example.com/", env: "proxy", want: "<nil>"},
+	{noenv: ".foo.com", req: "http://example.com/", env: "proxy", want: "http://proxy"},
 }
 
 func TestProxyFromEnvironment(t *testing.T) {
@@ -770,16 +1304,21 @@ func TestProxyFromEnvironment(t *testing.T) {
 	os.Setenv("http_proxy", "")
 	os.Setenv("NO_PROXY", "")
 	os.Setenv("no_proxy", "")
-	for i, tt := range proxyFromEnvTests {
+	for _, tt := range proxyFromEnvTests {
 		os.Setenv("HTTP_PROXY", tt.env)
-		req, _ := NewRequest("GET", "http://example.com", nil)
+		os.Setenv("NO_PROXY", tt.noenv)
+		reqURL := tt.req
+		if reqURL == "" {
+			reqURL = "http://example.com"
+		}
+		req, _ := NewRequest("GET", reqURL, nil)
 		url, err := ProxyFromEnvironment(req)
 		if g, e := fmt.Sprintf("%v", err), fmt.Sprintf("%v", tt.wanterr); g != e {
-			t.Errorf("%d. got error = %q, want %q", i, g, e)
+			t.Errorf("%v: got error = %q, want %q", tt, g, e)
 			continue
 		}
-		if got := fmt.Sprintf("%s", url); got != tt.wanturl {
-			t.Errorf("%d. got URL = %q, want %q", i, url, tt.wanturl)
+		if got := fmt.Sprintf("%s", url); got != tt.want {
+			t.Errorf("%v: got URL = %q, want %q", tt, url, tt.want)
 		}
 	}
 }