Adding upstream version 1.16.10.upstream/1.16.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1012 insertions, 0 deletions

diff --git a/src/net/http/response_test.go b/src/net/http/response_test.go
new file mode 100644
index 0000000..8eef654
--- /dev/null
+++ b/src/net/http/response_test.go
@@ -0,0 +1,1012 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"compress/gzip"
+	"crypto/rand"
+	"fmt"
+	"go/token"
+	"io"
+	"net/http/internal"
+	"net/url"
+	"reflect"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+type respTest struct {
+	Raw  string
+	Resp Response
+	Body string
+}
+
+func dummyReq(method string) *Request {
+	return &Request{Method: method}
+}
+
+func dummyReq11(method string) *Request {
+	return &Request{Method: method, Proto: "HTTP/1.1", ProtoMajor: 1, ProtoMinor: 1}
+}
+
+var respTests = []respTest{
+	// Unchunked response without Content-Length.
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Connection: close\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Connection": {"close"}, // TODO(rsc): Delete?
+			},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"Body here\n",
+	},
+
+	// Unchunked HTTP/1.1 response without Content-Length or
+	// Connection headers.
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:        "200 OK",
+			StatusCode:    200,
+			Proto:         "HTTP/1.1",
+			ProtoMajor:    1,
+			ProtoMinor:    1,
+			Header:        Header{},
+			Request:       dummyReq("GET"),
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"Body here\n",
+	},
+
+	// Unchunked HTTP/1.1 204 response without Content-Length.
+	{
+		"HTTP/1.1 204 No Content\r\n" +
+			"\r\n" +
+			"Body should not be read!\n",
+
+		Response{
+			Status:        "204 No Content",
+			StatusCode:    204,
+			Proto:         "HTTP/1.1",
+			ProtoMajor:    1,
+			ProtoMinor:    1,
+			Header:        Header{},
+			Request:       dummyReq("GET"),
+			Close:         false,
+			ContentLength: 0,
+		},
+
+		"",
+	},
+
+	// Unchunked response with Content-Length.
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Content-Length: 10\r\n" +
+			"Connection: close\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Connection":     {"close"},
+				"Content-Length": {"10"},
+			},
+			Close:         true,
+			ContentLength: 10,
+		},
+
+		"Body here\n",
+	},
+
+	// Chunked response without Content-Length.
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Transfer-Encoding: chunked\r\n" +
+			"\r\n" +
+			"0a\r\n" +
+			"Body here\n\r\n" +
+			"09\r\n" +
+			"continued\r\n" +
+			"0\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.1",
+			ProtoMajor:       1,
+			ProtoMinor:       1,
+			Request:          dummyReq("GET"),
+			Header:           Header{},
+			Close:            false,
+			ContentLength:    -1,
+			TransferEncoding: []string{"chunked"},
+		},
+
+		"Body here\ncontinued",
+	},
+
+	// Trailer header but no TransferEncoding
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Trailer: Content-MD5, Content-Sources\r\n" +
+			"Content-Length: 10\r\n" +
+			"Connection: close\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Connection":     {"close"},
+				"Content-Length": {"10"},
+				"Trailer":        []string{"Content-MD5, Content-Sources"},
+			},
+			Close:         true,
+			ContentLength: 10,
+		},
+
+		"Body here\n",
+	},
+
+	// Chunked response with Content-Length.
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Transfer-Encoding: chunked\r\n" +
+			"Content-Length: 10\r\n" +
+			"\r\n" +
+			"0a\r\n" +
+			"Body here\n\r\n" +
+			"0\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.1",
+			ProtoMajor:       1,
+			ProtoMinor:       1,
+			Request:          dummyReq("GET"),
+			Header:           Header{},
+			Close:            false,
+			ContentLength:    -1,
+			TransferEncoding: []string{"chunked"},
+		},
+
+		"Body here\n",
+	},
+
+	// Chunked response in response to a HEAD request
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Transfer-Encoding: chunked\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.1",
+			ProtoMajor:       1,
+			ProtoMinor:       1,
+			Request:          dummyReq("HEAD"),
+			Header:           Header{},
+			TransferEncoding: []string{"chunked"},
+			Close:            false,
+			ContentLength:    -1,
+		},
+
+		"",
+	},
+
+	// Content-Length in response to a HEAD request
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Content-Length: 256\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.0",
+			ProtoMajor:       1,
+			ProtoMinor:       0,
+			Request:          dummyReq("HEAD"),
+			Header:           Header{"Content-Length": {"256"}},
+			TransferEncoding: nil,
+			Close:            true,
+			ContentLength:    256,
+		},
+
+		"",
+	},
+
+	// Content-Length in response to a HEAD request with HTTP/1.1
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Content-Length: 256\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.1",
+			ProtoMajor:       1,
+			ProtoMinor:       1,
+			Request:          dummyReq("HEAD"),
+			Header:           Header{"Content-Length": {"256"}},
+			TransferEncoding: nil,
+			Close:            false,
+			ContentLength:    256,
+		},
+
+		"",
+	},
+
+	// No Content-Length or Chunked in response to a HEAD request
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"\r\n",
+
+		Response{
+			Status:           "200 OK",
+			StatusCode:       200,
+			Proto:            "HTTP/1.0",
+			ProtoMajor:       1,
+			ProtoMinor:       0,
+			Request:          dummyReq("HEAD"),
+			Header:           Header{},
+			TransferEncoding: nil,
+			Close:            true,
+			ContentLength:    -1,
+		},
+
+		"",
+	},
+
+	// explicit Content-Length of 0.
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Content-Length: 0\r\n" +
+			"\r\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Length": {"0"},
+			},
+			Close:         false,
+			ContentLength: 0,
+		},
+
+		"",
+	},
+
+	// Status line without a Reason-Phrase, but trailing space.
+	// (permitted by RFC 7230, section 3.1.2)
+	{
+		"HTTP/1.0 303 \r\n\r\n",
+		Response{
+			Status:        "303 ",
+			StatusCode:    303,
+			Proto:         "HTTP/1.0",
+			ProtoMajor:    1,
+			ProtoMinor:    0,
+			Request:       dummyReq("GET"),
+			Header:        Header{},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"",
+	},
+
+	// Status line without a Reason-Phrase, and no trailing space.
+	// (not permitted by RFC 7230, but we'll accept it anyway)
+	{
+		"HTTP/1.0 303\r\n\r\n",
+		Response{
+			Status:        "303",
+			StatusCode:    303,
+			Proto:         "HTTP/1.0",
+			ProtoMajor:    1,
+			ProtoMinor:    0,
+			Request:       dummyReq("GET"),
+			Header:        Header{},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"",
+	},
+
+	// golang.org/issue/4767: don't special-case multipart/byteranges responses
+	{
+		`HTTP/1.1 206 Partial Content
+Connection: close
+Content-Type: multipart/byteranges; boundary=18a75608c8f47cef
+
+some body`,
+		Response{
+			Status:     "206 Partial Content",
+			StatusCode: 206,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Type": []string{"multipart/byteranges; boundary=18a75608c8f47cef"},
+			},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"some body",
+	},
+
+	// Unchunked response without Content-Length, Request is nil
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Connection: close\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Header: Header{
+				"Connection": {"close"}, // TODO(rsc): Delete?
+			},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"Body here\n",
+	},
+
+	// 206 Partial Content. golang.org/issue/8923
+	{
+		"HTTP/1.1 206 Partial Content\r\n" +
+			"Content-Type: text/plain; charset=utf-8\r\n" +
+			"Accept-Ranges: bytes\r\n" +
+			"Content-Range: bytes 0-5/1862\r\n" +
+			"Content-Length: 6\r\n\r\n" +
+			"foobar",
+
+		Response{
+			Status:     "206 Partial Content",
+			StatusCode: 206,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Accept-Ranges":  []string{"bytes"},
+				"Content-Length": []string{"6"},
+				"Content-Type":   []string{"text/plain; charset=utf-8"},
+				"Content-Range":  []string{"bytes 0-5/1862"},
+			},
+			ContentLength: 6,
+		},
+
+		"foobar",
+	},
+
+	// Both keep-alive and close, on the same Connection line. (Issue 8840)
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Content-Length: 256\r\n" +
+			"Connection: keep-alive, close\r\n" +
+			"\r\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("HEAD"),
+			Header: Header{
+				"Content-Length": {"256"},
+			},
+			TransferEncoding: nil,
+			Close:            true,
+			ContentLength:    256,
+		},
+
+		"",
+	},
+
+	// Both keep-alive and close, on different Connection lines. (Issue 8840)
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Content-Length: 256\r\n" +
+			"Connection: keep-alive\r\n" +
+			"Connection: close\r\n" +
+			"\r\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("HEAD"),
+			Header: Header{
+				"Content-Length": {"256"},
+			},
+			TransferEncoding: nil,
+			Close:            true,
+			ContentLength:    256,
+		},
+
+		"",
+	},
+
+	// Issue 12785: HTTP/1.0 response with bogus (to be ignored) Transfer-Encoding.
+	// Without a Content-Length.
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Transfer-Encoding: bogus\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:        "200 OK",
+			StatusCode:    200,
+			Proto:         "HTTP/1.0",
+			ProtoMajor:    1,
+			ProtoMinor:    0,
+			Request:       dummyReq("GET"),
+			Header:        Header{},
+			Close:         true,
+			ContentLength: -1,
+		},
+
+		"Body here\n",
+	},
+
+	// Issue 12785: HTTP/1.0 response with bogus (to be ignored) Transfer-Encoding.
+	// With a Content-Length.
+	{
+		"HTTP/1.0 200 OK\r\n" +
+			"Transfer-Encoding: bogus\r\n" +
+			"Content-Length: 10\r\n" +
+			"\r\n" +
+			"Body here\n",
+
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Length": {"10"},
+			},
+			Close:         true,
+			ContentLength: 10,
+		},
+
+		"Body here\n",
+	},
+
+	{
+		"HTTP/1.1 200 OK\r\n" +
+			"Content-Encoding: gzip\r\n" +
+			"Content-Length: 23\r\n" +
+			"Connection: keep-alive\r\n" +
+			"Keep-Alive: timeout=7200\r\n\r\n" +
+			"\x1f\x8b\b\x00\x00\x00\x00\x00\x00\x00s\xf3\xf7\a\x00\xab'\xd4\x1a\x03\x00\x00\x00",
+		Response{
+			Status:     "200 OK",
+			StatusCode: 200,
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Length":   {"23"},
+				"Content-Encoding": {"gzip"},
+				"Connection":       {"keep-alive"},
+				"Keep-Alive":       {"timeout=7200"},
+			},
+			Close:         false,
+			ContentLength: 23,
+		},
+		"\x1f\x8b\b\x00\x00\x00\x00\x00\x00\x00s\xf3\xf7\a\x00\xab'\xd4\x1a\x03\x00\x00\x00",
+	},
+
+	// Issue 19989: two spaces between HTTP version and status.
+	{
+		"HTTP/1.0  401 Unauthorized\r\n" +
+			"Content-type: text/html\r\n" +
+			"WWW-Authenticate: Basic realm=\"\"\r\n\r\n" +
+			"Your Authentication failed.\r\n",
+		Response{
+			Status:     "401 Unauthorized",
+			StatusCode: 401,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Type":     {"text/html"},
+				"Www-Authenticate": {`Basic realm=""`},
+			},
+			Close:         true,
+			ContentLength: -1,
+		},
+		"Your Authentication failed.\r\n",
+	},
+}
+
+// tests successful calls to ReadResponse, and inspects the returned Response.
+// For error cases, see TestReadResponseErrors below.
+func TestReadResponse(t *testing.T) {
+	for i, tt := range respTests {
+		resp, err := ReadResponse(bufio.NewReader(strings.NewReader(tt.Raw)), tt.Resp.Request)
+		if err != nil {
+			t.Errorf("#%d: %v", i, err)
+			continue
+		}
+		rbody := resp.Body
+		resp.Body = nil
+		diff(t, fmt.Sprintf("#%d Response", i), resp, &tt.Resp)
+		var bout bytes.Buffer
+		if rbody != nil {
+			_, err = io.Copy(&bout, rbody)
+			if err != nil {
+				t.Errorf("#%d: %v", i, err)
+				continue
+			}
+			rbody.Close()
+		}
+		body := bout.String()
+		if body != tt.Body {
+			t.Errorf("#%d: Body = %q want %q", i, body, tt.Body)
+		}
+	}
+}
+
+func TestWriteResponse(t *testing.T) {
+	for i, tt := range respTests {
+		resp, err := ReadResponse(bufio.NewReader(strings.NewReader(tt.Raw)), tt.Resp.Request)
+		if err != nil {
+			t.Errorf("#%d: %v", i, err)
+			continue
+		}
+		err = resp.Write(io.Discard)
+		if err != nil {
+			t.Errorf("#%d: %v", i, err)
+			continue
+		}
+	}
+}
+
+var readResponseCloseInMiddleTests = []struct {
+	chunked, compressed bool
+}{
+	{false, false},
+	{true, false},
+	{true, true},
+}
+
+type readerAndCloser struct {
+	io.Reader
+	io.Closer
+}
+
+// TestReadResponseCloseInMiddle tests that closing a body after
+// reading only part of its contents advances the read to the end of
+// the request, right up until the next request.
+func TestReadResponseCloseInMiddle(t *testing.T) {
+	t.Parallel()
+	for _, test := range readResponseCloseInMiddleTests {
+		fatalf := func(format string, args ...interface{}) {
+			args = append([]interface{}{test.chunked, test.compressed}, args...)
+			t.Fatalf("on test chunked=%v, compressed=%v: "+format, args...)
+		}
+		checkErr := func(err error, msg string) {
+			if err == nil {
+				return
+			}
+			fatalf(msg+": %v", err)
+		}
+		var buf bytes.Buffer
+		buf.WriteString("HTTP/1.1 200 OK\r\n")
+		if test.chunked {
+			buf.WriteString("Transfer-Encoding: chunked\r\n")
+		} else {
+			buf.WriteString("Content-Length: 1000000\r\n")
+		}
+		var wr io.Writer = &buf
+		if test.chunked {
+			wr = internal.NewChunkedWriter(wr)
+		}
+		if test.compressed {
+			buf.WriteString("Content-Encoding: gzip\r\n")
+			wr = gzip.NewWriter(wr)
+		}
+		buf.WriteString("\r\n")
+
+		chunk := bytes.Repeat([]byte{'x'}, 1000)
+		for i := 0; i < 1000; i++ {
+			if test.compressed {
+				// Otherwise this compresses too well.
+				_, err := io.ReadFull(rand.Reader, chunk)
+				checkErr(err, "rand.Reader ReadFull")
+			}
+			wr.Write(chunk)
+		}
+		if test.compressed {
+			err := wr.(*gzip.Writer).Close()
+			checkErr(err, "compressor close")
+		}
+		if test.chunked {
+			buf.WriteString("0\r\n\r\n")
+		}
+		buf.WriteString("Next Request Here")
+
+		bufr := bufio.NewReader(&buf)
+		resp, err := ReadResponse(bufr, dummyReq("GET"))
+		checkErr(err, "ReadResponse")
+		expectedLength := int64(-1)
+		if !test.chunked {
+			expectedLength = 1000000
+		}
+		if resp.ContentLength != expectedLength {
+			fatalf("expected response length %d, got %d", expectedLength, resp.ContentLength)
+		}
+		if resp.Body == nil {
+			fatalf("nil body")
+		}
+		if test.compressed {
+			gzReader, err := gzip.NewReader(resp.Body)
+			checkErr(err, "gzip.NewReader")
+			resp.Body = &readerAndCloser{gzReader, resp.Body}
+		}
+
+		rbuf := make([]byte, 2500)
+		n, err := io.ReadFull(resp.Body, rbuf)
+		checkErr(err, "2500 byte ReadFull")
+		if n != 2500 {
+			fatalf("ReadFull only read %d bytes", n)
+		}
+		if test.compressed == false && !bytes.Equal(bytes.Repeat([]byte{'x'}, 2500), rbuf) {
+			fatalf("ReadFull didn't read 2500 'x'; got %q", string(rbuf))
+		}
+		resp.Body.Close()
+
+		rest, err := io.ReadAll(bufr)
+		checkErr(err, "ReadAll on remainder")
+		if e, g := "Next Request Here", string(rest); e != g {
+			g = regexp.MustCompile(`(xx+)`).ReplaceAllStringFunc(g, func(match string) string {
+				return fmt.Sprintf("x(repeated x%d)", len(match))
+			})
+			fatalf("remainder = %q, expected %q", g, e)
+		}
+	}
+}
+
+func diff(t *testing.T, prefix string, have, want interface{}) {
+	t.Helper()
+	hv := reflect.ValueOf(have).Elem()
+	wv := reflect.ValueOf(want).Elem()
+	if hv.Type() != wv.Type() {
+		t.Errorf("%s: type mismatch %v want %v", prefix, hv.Type(), wv.Type())
+	}
+	for i := 0; i < hv.NumField(); i++ {
+		name := hv.Type().Field(i).Name
+		if !token.IsExported(name) {
+			continue
+		}
+		hf := hv.Field(i).Interface()
+		wf := wv.Field(i).Interface()
+		if !reflect.DeepEqual(hf, wf) {
+			t.Errorf("%s: %s = %v want %v", prefix, name, hf, wf)
+		}
+	}
+}
+
+type responseLocationTest struct {
+	location string // Response's Location header or ""
+	requrl   string // Response.Request.URL or ""
+	want     string
+	wantErr  error
+}
+
+var responseLocationTests = []responseLocationTest{
+	{"/foo", "http://bar.com/baz", "http://bar.com/foo", nil},
+	{"http://foo.com/", "http://bar.com/baz", "http://foo.com/", nil},
+	{"", "http://bar.com/baz", "", ErrNoLocation},
+	{"/bar", "", "/bar", nil},
+}
+
+func TestLocationResponse(t *testing.T) {
+	for i, tt := range responseLocationTests {
+		res := new(Response)
+		res.Header = make(Header)
+		res.Header.Set("Location", tt.location)
+		if tt.requrl != "" {
+			res.Request = &Request{}
+			var err error
+			res.Request.URL, err = url.Parse(tt.requrl)
+			if err != nil {
+				t.Fatalf("bad test URL %q: %v", tt.requrl, err)
+			}
+		}
+
+		got, err := res.Location()
+		if tt.wantErr != nil {
+			if err == nil {
+				t.Errorf("%d. err=nil; want %q", i, tt.wantErr)
+				continue
+			}
+			if g, e := err.Error(), tt.wantErr.Error(); g != e {
+				t.Errorf("%d. err=%q; want %q", i, g, e)
+				continue
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("%d. err=%q", i, err)
+			continue
+		}
+		if g, e := got.String(), tt.want; g != e {
+			t.Errorf("%d. Location=%q; want %q", i, g, e)
+		}
+	}
+}
+
+func TestResponseStatusStutter(t *testing.T) {
+	r := &Response{
+		Status:     "123 some status",
+		StatusCode: 123,
+		ProtoMajor: 1,
+		ProtoMinor: 3,
+	}
+	var buf bytes.Buffer
+	r.Write(&buf)
+	if strings.Contains(buf.String(), "123 123") {
+		t.Errorf("stutter in status: %s", buf.String())
+	}
+}
+
+func TestResponseContentLengthShortBody(t *testing.T) {
+	const shortBody = "Short body, not 123 bytes."
+	br := bufio.NewReader(strings.NewReader("HTTP/1.1 200 OK\r\n" +
+		"Content-Length: 123\r\n" +
+		"\r\n" +
+		shortBody))
+	res, err := ReadResponse(br, &Request{Method: "GET"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.ContentLength != 123 {
+		t.Fatalf("Content-Length = %d; want 123", res.ContentLength)
+	}
+	var buf bytes.Buffer
+	n, err := io.Copy(&buf, res.Body)
+	if n != int64(len(shortBody)) {
+		t.Errorf("Copied %d bytes; want %d, len(%q)", n, len(shortBody), shortBody)
+	}
+	if buf.String() != shortBody {
+		t.Errorf("Read body %q; want %q", buf.String(), shortBody)
+	}
+	if err != io.ErrUnexpectedEOF {
+		t.Errorf("io.Copy error = %#v; want io.ErrUnexpectedEOF", err)
+	}
+}
+
+// Test various ReadResponse error cases. (also tests success cases, but mostly
+// it's about errors).  This does not test anything involving the bodies. Only
+// the return value from ReadResponse itself.
+func TestReadResponseErrors(t *testing.T) {
+	type testCase struct {
+		name    string // optional, defaults to in
+		in      string
+		wantErr interface{} // nil, err value, or string substring
+	}
+
+	status := func(s string, wantErr interface{}) testCase {
+		if wantErr == true {
+			wantErr = "malformed HTTP status code"
+		}
+		return testCase{
+			name:    fmt.Sprintf("status %q", s),
+			in:      "HTTP/1.1 " + s + "\r\nFoo: bar\r\n\r\n",
+			wantErr: wantErr,
+		}
+	}
+
+	version := func(s string, wantErr interface{}) testCase {
+		if wantErr == true {
+			wantErr = "malformed HTTP version"
+		}
+		return testCase{
+			name:    fmt.Sprintf("version %q", s),
+			in:      s + " 200 OK\r\n\r\n",
+			wantErr: wantErr,
+		}
+	}
+
+	contentLength := func(status, body string, wantErr interface{}) testCase {
+		return testCase{
+			name:    fmt.Sprintf("status %q %q", status, body),
+			in:      fmt.Sprintf("HTTP/1.1 %s\r\n%s", status, body),
+			wantErr: wantErr,
+		}
+	}
+
+	errMultiCL := "message cannot contain multiple Content-Length headers"
+
+	tests := []testCase{
+		{"", "", io.ErrUnexpectedEOF},
+		{"", "HTTP/1.1 301 Moved Permanently\r\nFoo: bar", io.ErrUnexpectedEOF},
+		{"", "HTTP/1.1", "malformed HTTP response"},
+		{"", "HTTP/2.0", "malformed HTTP response"},
+		status("20X Unknown", true),
+		status("abcd Unknown", true),
+		status("二百/两百 OK", true),
+		status(" Unknown", true),
+		status("c8 OK", true),
+		status("0x12d Moved Permanently", true),
+		status("200 OK", nil),
+		status("000 OK", nil),
+		status("001 OK", nil),
+		status("404 NOTFOUND", nil),
+		status("20 OK", true),
+		status("00 OK", true),
+		status("-10 OK", true),
+		status("1000 OK", true),
+		status("999 Done", nil),
+		status("-1 OK", true),
+		status("-200 OK", true),
+		version("HTTP/1.2", nil),
+		version("HTTP/2.0", nil),
+		version("HTTP/1.100000000002", true),
+		version("HTTP/1.-1", true),
+		version("HTTP/A.B", true),
+		version("HTTP/1", true),
+		version("http/1.1", true),
+
+		contentLength("200 OK", "Content-Length: 10\r\nContent-Length: 7\r\n\r\nGopher hey\r\n", errMultiCL),
+		contentLength("200 OK", "Content-Length: 7\r\nContent-Length: 7\r\n\r\nGophers\r\n", nil),
+		contentLength("201 OK", "Content-Length: 0\r\nContent-Length: 7\r\n\r\nGophers\r\n", errMultiCL),
+		contentLength("300 OK", "Content-Length: 0\r\nContent-Length: 0 \r\n\r\nGophers\r\n", nil),
+		contentLength("200 OK", "Content-Length:\r\nContent-Length:\r\n\r\nGophers\r\n", nil),
+		contentLength("206 OK", "Content-Length:\r\nContent-Length: 0 \r\nConnection: close\r\n\r\nGophers\r\n", errMultiCL),
+
+		// multiple content-length headers for 204 and 304 should still be checked
+		contentLength("204 OK", "Content-Length: 7\r\nContent-Length: 8\r\n\r\n", errMultiCL),
+		contentLength("204 OK", "Content-Length: 3\r\nContent-Length: 3\r\n\r\n", nil),
+		contentLength("304 OK", "Content-Length: 880\r\nContent-Length: 1\r\n\r\n", errMultiCL),
+		contentLength("304 OK", "Content-Length: 961\r\nContent-Length: 961\r\n\r\n", nil),
+
+		// golang.org/issue/22464
+		{"leading space in header", "HTTP/1.1 200 OK\r\n Content-type: text/html\r\nFoo: bar\r\n\r\n", "malformed MIME"},
+		{"leading tab in header", "HTTP/1.1 200 OK\r\n\tContent-type: text/html\r\nFoo: bar\r\n\r\n", "malformed MIME"},
+	}
+
+	for i, tt := range tests {
+		br := bufio.NewReader(strings.NewReader(tt.in))
+		_, rerr := ReadResponse(br, nil)
+		if err := matchErr(rerr, tt.wantErr); err != nil {
+			name := tt.name
+			if name == "" {
+				name = fmt.Sprintf("%d. input %q", i, tt.in)
+			}
+			t.Errorf("%s: %v", name, err)
+		}
+	}
+}
+
+// wantErr can be nil, an error value to match exactly, or type string to
+// match a substring.
+func matchErr(err error, wantErr interface{}) error {
+	if err == nil {
+		if wantErr == nil {
+			return nil
+		}
+		if sub, ok := wantErr.(string); ok {
+			return fmt.Errorf("unexpected success; want error with substring %q", sub)
+		}
+		return fmt.Errorf("unexpected success; want error %v", wantErr)
+	}
+	if wantErr == nil {
+		return fmt.Errorf("%v; want success", err)
+	}
+	if sub, ok := wantErr.(string); ok {
+		if strings.Contains(err.Error(), sub) {
+			return nil
+		}
+		return fmt.Errorf("error = %v; want an error with substring %q", err, sub)
+	}
+	if err == wantErr {
+		return nil
+	}
+	return fmt.Errorf("%v; want %v", err, wantErr)
+}
+
+func TestNeedsSniff(t *testing.T) {
+	// needsSniff returns true with an empty response.
+	r := &response{}
+	if got, want := r.needsSniff(), true; got != want {
+		t.Errorf("needsSniff = %t; want %t", got, want)
+	}
+	// needsSniff returns false when Content-Type = nil.
+	r.handlerHeader = Header{"Content-Type": nil}
+	if got, want := r.needsSniff(), false; got != want {
+		t.Errorf("needsSniff empty Content-Type = %t; want %t", got, want)
+	}
+}
+
+// A response should only write out single Connection: close header. Tests #19499.
+func TestResponseWritesOnlySingleConnectionClose(t *testing.T) {
+	const connectionCloseHeader = "Connection: close"
+
+	res, err := ReadResponse(bufio.NewReader(strings.NewReader("HTTP/1.0 200 OK\r\n\r\nAAAA")), nil)
+	if err != nil {
+		t.Fatalf("ReadResponse failed %v", err)
+	}
+
+	var buf1 bytes.Buffer
+	if err = res.Write(&buf1); err != nil {
+		t.Fatalf("Write failed %v", err)
+	}
+	if res, err = ReadResponse(bufio.NewReader(&buf1), nil); err != nil {
+		t.Fatalf("ReadResponse failed %v", err)
+	}
+
+	var buf2 bytes.Buffer
+	if err = res.Write(&buf2); err != nil {
+		t.Fatalf("Write failed %v", err)
+	}
+	if count := strings.Count(buf2.String(), connectionCloseHeader); count != 1 {
+		t.Errorf("Found %d %q header", count, connectionCloseHeader)
+	}
+}