libgo/go/net/http/fs_test.go

   1 // Copyright 2010 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package http_test
   6
   7 import (
   8         "bufio"
   9         "bytes"
  10         "errors"
  11         "fmt"
  12         "io"
  13         "io/ioutil"
  14         "mime"
  15         "mime/multipart"
  16         "net"
  17         . "net/http"
  18         "net/http/httptest"
  19         "net/url"
  20         "os"
  21         "os/exec"
  22         "path"
  23         "path/filepath"
  24         "reflect"
  25         "regexp"
  26         "runtime"
  27         "strings"
  28         "testing"
  29         "time"
  30 )
  31
  32 const (
  33         testFile    = "testdata/file"
  34         testFileLen = 11
  35 )
  36
  37 type wantRange struct {
  38         start, end int64 // range [start,end)
  39 }
  40
  41 var ServeFileRangeTests = []struct {
  42         r      string
  43         code   int
  44         ranges []wantRange
  45 }{
  46         {r: "", code: StatusOK},
  47         {r: "bytes=0-4", code: StatusPartialContent, ranges: []wantRange{{0, 5}}},
  48         {r: "bytes=2-", code: StatusPartialContent, ranges: []wantRange{{2, testFileLen}}},
  49         {r: "bytes=-5", code: StatusPartialContent, ranges: []wantRange{{testFileLen - 5, testFileLen}}},
  50         {r: "bytes=3-7", code: StatusPartialContent, ranges: []wantRange{{3, 8}}},
  51         {r: "bytes=0-0,-2", code: StatusPartialContent, ranges: []wantRange{{0, 1}, {testFileLen - 2, testFileLen}}},
  52         {r: "bytes=0-1,5-8", code: StatusPartialContent, ranges: []wantRange{{0, 2}, {5, 9}}},
  53         {r: "bytes=0-1,5-", code: StatusPartialContent, ranges: []wantRange{{0, 2}, {5, testFileLen}}},
  54         {r: "bytes=5-1000", code: StatusPartialContent, ranges: []wantRange{{5, testFileLen}}},
  55         {r: "bytes=0-,1-,2-,3-,4-", code: StatusOK}, // ignore wasteful range request
  56         {r: "bytes=0-9", code: StatusPartialContent, ranges: []wantRange{{0, testFileLen - 1}}},
  57         {r: "bytes=0-10", code: StatusPartialContent, ranges: []wantRange{{0, testFileLen}}},
  58         {r: "bytes=0-11", code: StatusPartialContent, ranges: []wantRange{{0, testFileLen}}},
  59         {r: "bytes=10-11", code: StatusPartialContent, ranges: []wantRange{{testFileLen - 1, testFileLen}}},
  60         {r: "bytes=10-", code: StatusPartialContent, ranges: []wantRange{{testFileLen - 1, testFileLen}}},
  61         {r: "bytes=11-", code: StatusRequestedRangeNotSatisfiable},
  62         {r: "bytes=11-12", code: StatusRequestedRangeNotSatisfiable},
  63         {r: "bytes=12-12", code: StatusRequestedRangeNotSatisfiable},
  64         {r: "bytes=11-100", code: StatusRequestedRangeNotSatisfiable},
  65         {r: "bytes=12-100", code: StatusRequestedRangeNotSatisfiable},
  66         {r: "bytes=100-", code: StatusRequestedRangeNotSatisfiable},
  67         {r: "bytes=100-1000", code: StatusRequestedRangeNotSatisfiable},
  68 }
  69
  70 func TestServeFile(t *testing.T) {
  71         setParallel(t)
  72         defer afterTest(t)
  73         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
  74                 ServeFile(w, r, "testdata/file")
  75         }))
  76         defer ts.Close()
  77         c := ts.Client()
  78
  79         var err error
  80
  81         file, err := ioutil.ReadFile(testFile)
  82         if err != nil {
  83                 t.Fatal("reading file:", err)
  84         }
  85
  86         // set up the Request (re-used for all tests)
  87         var req Request
  88         req.Header = make(Header)
  89         if req.URL, err = url.Parse(ts.URL); err != nil {
  90                 t.Fatal("ParseURL:", err)
  91         }
  92         req.Method = "GET"
  93
  94         // straight GET
  95         _, body := getBody(t, "straight get", req, c)
  96         if !bytes.Equal(body, file) {
  97                 t.Fatalf("body mismatch: got %q, want %q", body, file)
  98         }
  99
 100         // Range tests
 101 Cases:
 102         for _, rt := range ServeFileRangeTests {
 103                 if rt.r != "" {
 104                         req.Header.Set("Range", rt.r)
 105                 }
 106                 resp, body := getBody(t, fmt.Sprintf("range test %q", rt.r), req, c)
 107                 if resp.StatusCode != rt.code {
 108                         t.Errorf("range=%q: StatusCode=%d, want %d", rt.r, resp.StatusCode, rt.code)
 109                 }
 110                 if rt.code == StatusRequestedRangeNotSatisfiable {
 111                         continue
 112                 }
 113                 wantContentRange := ""
 114                 if len(rt.ranges) == 1 {
 115                         rng := rt.ranges[0]
 116                         wantContentRange = fmt.Sprintf("bytes %d-%d/%d", rng.start, rng.end-1, testFileLen)
 117                 }
 118                 cr := resp.Header.Get("Content-Range")
 119                 if cr != wantContentRange {
 120                         t.Errorf("range=%q: Content-Range = %q, want %q", rt.r, cr, wantContentRange)
 121                 }
 122                 ct := resp.Header.Get("Content-Type")
 123                 if len(rt.ranges) == 1 {
 124                         rng := rt.ranges[0]
 125                         wantBody := file[rng.start:rng.end]
 126                         if !bytes.Equal(body, wantBody) {
 127                                 t.Errorf("range=%q: body = %q, want %q", rt.r, body, wantBody)
 128                         }
 129                         if strings.HasPrefix(ct, "multipart/byteranges") {
 130                                 t.Errorf("range=%q content-type = %q; unexpected multipart/byteranges", rt.r, ct)
 131                         }
 132                 }
 133                 if len(rt.ranges) > 1 {
 134                         typ, params, err := mime.ParseMediaType(ct)
 135                         if err != nil {
 136                                 t.Errorf("range=%q content-type = %q; %v", rt.r, ct, err)
 137                                 continue
 138                         }
 139                         if typ != "multipart/byteranges" {
 140                                 t.Errorf("range=%q content-type = %q; want multipart/byteranges", rt.r, typ)
 141                                 continue
 142                         }
 143                         if params["boundary"] == "" {
 144                                 t.Errorf("range=%q content-type = %q; lacks boundary", rt.r, ct)
 145                                 continue
 146                         }
 147                         if g, w := resp.ContentLength, int64(len(body)); g != w {
 148                                 t.Errorf("range=%q Content-Length = %d; want %d", rt.r, g, w)
 149                                 continue
 150                         }
 151                         mr := multipart.NewReader(bytes.NewReader(body), params["boundary"])
 152                         for ri, rng := range rt.ranges {
 153                                 part, err := mr.NextPart()
 154                                 if err != nil {
 155                                         t.Errorf("range=%q, reading part index %d: %v", rt.r, ri, err)
 156                                         continue Cases
 157                                 }
 158                                 wantContentRange = fmt.Sprintf("bytes %d-%d/%d", rng.start, rng.end-1, testFileLen)
 159                                 if g, w := part.Header.Get("Content-Range"), wantContentRange; g != w {
 160                                         t.Errorf("range=%q: part Content-Range = %q; want %q", rt.r, g, w)
 161                                 }
 162                                 body, err := ioutil.ReadAll(part)
 163                                 if err != nil {
 164                                         t.Errorf("range=%q, reading part index %d body: %v", rt.r, ri, err)
 165                                         continue Cases
 166                                 }
 167                                 wantBody := file[rng.start:rng.end]
 168                                 if !bytes.Equal(body, wantBody) {
 169                                         t.Errorf("range=%q: body = %q, want %q", rt.r, body, wantBody)
 170                                 }
 171                         }
 172                         _, err = mr.NextPart()
 173                         if err != io.EOF {
 174                                 t.Errorf("range=%q; expected final error io.EOF; got %v", rt.r, err)
 175                         }
 176                 }
 177         }
 178 }
 179
 180 func TestServeFile_DotDot(t *testing.T) {
 181         tests := []struct {
 182                 req        string
 183                 wantStatus int
 184         }{
 185                 {"/testdata/file", 200},
 186                 {"/../file", 400},
 187                 {"/..", 400},
 188                 {"/../", 400},
 189                 {"/../foo", 400},
 190                 {"/..\\foo", 400},
 191                 {"/file/a", 200},
 192                 {"/file/a..", 200},
 193                 {"/file/a/..", 400},
 194                 {"/file/a\\..", 400},
 195         }
 196         for _, tt := range tests {
 197                 req, err := ReadRequest(bufio.NewReader(strings.NewReader("GET " + tt.req + " HTTP/1.1\r\nHost: foo\r\n\r\n")))
 198                 if err != nil {
 199                         t.Errorf("bad request %q: %v", tt.req, err)
 200                         continue
 201                 }
 202                 rec := httptest.NewRecorder()
 203                 ServeFile(rec, req, "testdata/file")
 204                 if rec.Code != tt.wantStatus {
 205                         t.Errorf("for request %q, status = %d; want %d", tt.req, rec.Code, tt.wantStatus)
 206                 }
 207         }
 208 }
 209
 210 var fsRedirectTestData = []struct {
 211         original, redirect string
 212 }{
 213         {"/test/index.html", "/test/"},
 214         {"/test/testdata", "/test/testdata/"},
 215         {"/test/testdata/file/", "/test/testdata/file"},
 216 }
 217
 218 func TestFSRedirect(t *testing.T) {
 219         defer afterTest(t)
 220         ts := httptest.NewServer(StripPrefix("/test", FileServer(Dir("."))))
 221         defer ts.Close()
 222
 223         for _, data := range fsRedirectTestData {
 224                 res, err := Get(ts.URL + data.original)
 225                 if err != nil {
 226                         t.Fatal(err)
 227                 }
 228                 res.Body.Close()
 229                 if g, e := res.Request.URL.Path, data.redirect; g != e {
 230                         t.Errorf("redirect from %s: got %s, want %s", data.original, g, e)
 231                 }
 232         }
 233 }
 234
 235 type testFileSystem struct {
 236         open func(name string) (File, error)
 237 }
 238
 239 func (fs *testFileSystem) Open(name string) (File, error) {
 240         return fs.open(name)
 241 }
 242
 243 func TestFileServerCleans(t *testing.T) {
 244         defer afterTest(t)
 245         ch := make(chan string, 1)
 246         fs := FileServer(&testFileSystem{func(name string) (File, error) {
 247                 ch <- name
 248                 return nil, errors.New("file does not exist")
 249         }})
 250         tests := []struct {
 251                 reqPath, openArg string
 252         }{
 253                 {"/foo.txt", "/foo.txt"},
 254                 {"//foo.txt", "/foo.txt"},
 255                 {"/../foo.txt", "/foo.txt"},
 256         }
 257         req, _ := NewRequest("GET", "http://example.com", nil)
 258         for n, test := range tests {
 259                 rec := httptest.NewRecorder()
 260                 req.URL.Path = test.reqPath
 261                 fs.ServeHTTP(rec, req)
 262                 if got := <-ch; got != test.openArg {
 263                         t.Errorf("test %d: got %q, want %q", n, got, test.openArg)
 264                 }
 265         }
 266 }
 267
 268 func TestFileServerEscapesNames(t *testing.T) {
 269         defer afterTest(t)
 270         const dirListPrefix = "<pre>\n"
 271         const dirListSuffix = "\n</pre>\n"
 272         tests := []struct {
 273                 name, escaped string
 274         }{
 275                 {`simple_name`, `<a href="simple_name">simple_name</a>`},
 276                 {`"'<>&`, `<a href="%22%27%3C%3E&">&#34;&#39;&lt;&gt;&amp;</a>`},
 277                 {`?foo=bar#baz`, `<a href="%3Ffoo=bar%23baz">?foo=bar#baz</a>`},
 278                 {`<combo>?foo`, `<a href="%3Ccombo%3E%3Ffoo">&lt;combo&gt;?foo</a>`},
 279                 {`foo:bar`, `<a href="./foo:bar">foo:bar</a>`},
 280         }
 281
 282         // We put each test file in its own directory in the fakeFS so we can look at it in isolation.
 283         fs := make(fakeFS)
 284         for i, test := range tests {
 285                 testFile := &fakeFileInfo{basename: test.name}
 286                 fs[fmt.Sprintf("/%d", i)] = &fakeFileInfo{
 287                         dir:     true,
 288                         modtime: time.Unix(1000000000, 0).UTC(),
 289                         ents:    []*fakeFileInfo{testFile},
 290                 }
 291                 fs[fmt.Sprintf("/%d/%s", i, test.name)] = testFile
 292         }
 293
 294         ts := httptest.NewServer(FileServer(&fs))
 295         defer ts.Close()
 296         for i, test := range tests {
 297                 url := fmt.Sprintf("%s/%d", ts.URL, i)
 298                 res, err := Get(url)
 299                 if err != nil {
 300                         t.Fatalf("test %q: Get: %v", test.name, err)
 301                 }
 302                 b, err := ioutil.ReadAll(res.Body)
 303                 if err != nil {
 304                         t.Fatalf("test %q: read Body: %v", test.name, err)
 305                 }
 306                 s := string(b)
 307                 if !strings.HasPrefix(s, dirListPrefix) || !strings.HasSuffix(s, dirListSuffix) {
 308                         t.Errorf("test %q: listing dir, full output is %q, want prefix %q and suffix %q", test.name, s, dirListPrefix, dirListSuffix)
 309                 }
 310                 if trimmed := strings.TrimSuffix(strings.TrimPrefix(s, dirListPrefix), dirListSuffix); trimmed != test.escaped {
 311                         t.Errorf("test %q: listing dir, filename escaped to %q, want %q", test.name, trimmed, test.escaped)
 312                 }
 313                 res.Body.Close()
 314         }
 315 }
 316
 317 func TestFileServerSortsNames(t *testing.T) {
 318         defer afterTest(t)
 319         const contents = "I am a fake file"
 320         dirMod := time.Unix(123, 0).UTC()
 321         fileMod := time.Unix(1000000000, 0).UTC()
 322         fs := fakeFS{
 323                 "/": &fakeFileInfo{
 324                         dir:     true,
 325                         modtime: dirMod,
 326                         ents: []*fakeFileInfo{
 327                                 {
 328                                         basename: "b",
 329                                         modtime:  fileMod,
 330                                         contents: contents,
 331                                 },
 332                                 {
 333                                         basename: "a",
 334                                         modtime:  fileMod,
 335                                         contents: contents,
 336                                 },
 337                         },
 338                 },
 339         }
 340
 341         ts := httptest.NewServer(FileServer(&fs))
 342         defer ts.Close()
 343
 344         res, err := Get(ts.URL)
 345         if err != nil {
 346                 t.Fatalf("Get: %v", err)
 347         }
 348         defer res.Body.Close()
 349
 350         b, err := ioutil.ReadAll(res.Body)
 351         if err != nil {
 352                 t.Fatalf("read Body: %v", err)
 353         }
 354         s := string(b)
 355         if !strings.Contains(s, "<a href=\"a\">a</a>\n<a href=\"b\">b</a>") {
 356                 t.Errorf("output appears to be unsorted:\n%s", s)
 357         }
 358 }
 359
 360 func mustRemoveAll(dir string) {
 361         err := os.RemoveAll(dir)
 362         if err != nil {
 363                 panic(err)
 364         }
 365 }
 366
 367 func TestFileServerImplicitLeadingSlash(t *testing.T) {
 368         defer afterTest(t)
 369         tempDir, err := ioutil.TempDir("", "")
 370         if err != nil {
 371                 t.Fatalf("TempDir: %v", err)
 372         }
 373         defer mustRemoveAll(tempDir)
 374         if err := ioutil.WriteFile(filepath.Join(tempDir, "foo.txt"), []byte("Hello world"), 0644); err != nil {
 375                 t.Fatalf("WriteFile: %v", err)
 376         }
 377         ts := httptest.NewServer(StripPrefix("/bar/", FileServer(Dir(tempDir))))
 378         defer ts.Close()
 379         get := func(suffix string) string {
 380                 res, err := Get(ts.URL + suffix)
 381                 if err != nil {
 382                         t.Fatalf("Get %s: %v", suffix, err)
 383                 }
 384                 b, err := ioutil.ReadAll(res.Body)
 385                 if err != nil {
 386                         t.Fatalf("ReadAll %s: %v", suffix, err)
 387                 }
 388                 res.Body.Close()
 389                 return string(b)
 390         }
 391         if s := get("/bar/"); !strings.Contains(s, ">foo.txt<") {
 392                 t.Logf("expected a directory listing with foo.txt, got %q", s)
 393         }
 394         if s := get("/bar/foo.txt"); s != "Hello world" {
 395                 t.Logf("expected %q, got %q", "Hello world", s)
 396         }
 397 }
 398
 399 func TestDirJoin(t *testing.T) {
 400         if runtime.GOOS == "windows" {
 401                 t.Skip("skipping test on windows")
 402         }
 403         wfi, err := os.Stat("/etc/hosts")
 404         if err != nil {
 405                 t.Skip("skipping test; no /etc/hosts file")
 406         }
 407         test := func(d Dir, name string) {
 408                 f, err := d.Open(name)
 409                 if err != nil {
 410                         t.Fatalf("open of %s: %v", name, err)
 411                 }
 412                 defer f.Close()
 413                 gfi, err := f.Stat()
 414                 if err != nil {
 415                         t.Fatalf("stat of %s: %v", name, err)
 416                 }
 417                 if !os.SameFile(gfi, wfi) {
 418                         t.Errorf("%s got different file", name)
 419                 }
 420         }
 421         test(Dir("/etc/"), "/hosts")
 422         test(Dir("/etc/"), "hosts")
 423         test(Dir("/etc/"), "../../../../hosts")
 424         test(Dir("/etc"), "/hosts")
 425         test(Dir("/etc"), "hosts")
 426         test(Dir("/etc"), "../../../../hosts")
 427
 428         // Not really directories, but since we use this trick in
 429         // ServeFile, test it:
 430         test(Dir("/etc/hosts"), "")
 431         test(Dir("/etc/hosts"), "/")
 432         test(Dir("/etc/hosts"), "../")
 433 }
 434
 435 func TestEmptyDirOpenCWD(t *testing.T) {
 436         test := func(d Dir) {
 437                 name := "fs_test.go"
 438                 f, err := d.Open(name)
 439                 if err != nil {
 440                         t.Fatalf("open of %s: %v", name, err)
 441                 }
 442                 defer f.Close()
 443         }
 444         test(Dir(""))
 445         test(Dir("."))
 446         test(Dir("./"))
 447 }
 448
 449 func TestServeFileContentType(t *testing.T) {
 450         defer afterTest(t)
 451         const ctype = "icecream/chocolate"
 452         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 453                 switch r.FormValue("override") {
 454                 case "1":
 455                         w.Header().Set("Content-Type", ctype)
 456                 case "2":
 457                         // Explicitly inhibit sniffing.
 458                         w.Header()["Content-Type"] = []string{}
 459                 }
 460                 ServeFile(w, r, "testdata/file")
 461         }))
 462         defer ts.Close()
 463         get := func(override string, want []string) {
 464                 resp, err := Get(ts.URL + "?override=" + override)
 465                 if err != nil {
 466                         t.Fatal(err)
 467                 }
 468                 if h := resp.Header["Content-Type"]; !reflect.DeepEqual(h, want) {
 469                         t.Errorf("Content-Type mismatch: got %v, want %v", h, want)
 470                 }
 471                 resp.Body.Close()
 472         }
 473         get("0", []string{"text/plain; charset=utf-8"})
 474         get("1", []string{ctype})
 475         get("2", nil)
 476 }
 477
 478 func TestServeFileMimeType(t *testing.T) {
 479         defer afterTest(t)
 480         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 481                 ServeFile(w, r, "testdata/style.css")
 482         }))
 483         defer ts.Close()
 484         resp, err := Get(ts.URL)
 485         if err != nil {
 486                 t.Fatal(err)
 487         }
 488         resp.Body.Close()
 489         want := "text/css; charset=utf-8"
 490         if h := resp.Header.Get("Content-Type"); h != want {
 491                 t.Errorf("Content-Type mismatch: got %q, want %q", h, want)
 492         }
 493 }
 494
 495 func TestServeFileFromCWD(t *testing.T) {
 496         defer afterTest(t)
 497         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 498                 ServeFile(w, r, "fs_test.go")
 499         }))
 500         defer ts.Close()
 501         r, err := Get(ts.URL)
 502         if err != nil {
 503                 t.Fatal(err)
 504         }
 505         r.Body.Close()
 506         if r.StatusCode != 200 {
 507                 t.Fatalf("expected 200 OK, got %s", r.Status)
 508         }
 509 }
 510
 511 // Issue 13996
 512 func TestServeDirWithoutTrailingSlash(t *testing.T) {
 513         e := "/testdata/"
 514         defer afterTest(t)
 515         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 516                 ServeFile(w, r, ".")
 517         }))
 518         defer ts.Close()
 519         r, err := Get(ts.URL + "/testdata")
 520         if err != nil {
 521                 t.Fatal(err)
 522         }
 523         r.Body.Close()
 524         if g := r.Request.URL.Path; g != e {
 525                 t.Errorf("got %s, want %s", g, e)
 526         }
 527 }
 528
 529 // Tests that ServeFile doesn't add a Content-Length if a Content-Encoding is
 530 // specified.
 531 func TestServeFileWithContentEncoding_h1(t *testing.T) { testServeFileWithContentEncoding(t, h1Mode) }
 532 func TestServeFileWithContentEncoding_h2(t *testing.T) { testServeFileWithContentEncoding(t, h2Mode) }
 533 func testServeFileWithContentEncoding(t *testing.T, h2 bool) {
 534         defer afterTest(t)
 535         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
 536                 w.Header().Set("Content-Encoding", "foo")
 537                 ServeFile(w, r, "testdata/file")
 538
 539                 // Because the testdata is so small, it would fit in
 540                 // both the h1 and h2 Server's write buffers. For h1,
 541                 // sendfile is used, though, forcing a header flush at
 542                 // the io.Copy. http2 doesn't do a header flush so
 543                 // buffers all 11 bytes and then adds its own
 544                 // Content-Length. To prevent the Server's
 545                 // Content-Length and test ServeFile only, flush here.
 546                 w.(Flusher).Flush()
 547         }))
 548         defer cst.close()
 549         resp, err := cst.c.Get(cst.ts.URL)
 550         if err != nil {
 551                 t.Fatal(err)
 552         }
 553         resp.Body.Close()
 554         if g, e := resp.ContentLength, int64(-1); g != e {
 555                 t.Errorf("Content-Length mismatch: got %d, want %d", g, e)
 556         }
 557 }
 558
 559 func TestServeIndexHtml(t *testing.T) {
 560         defer afterTest(t)
 561         const want = "index.html says hello\n"
 562         ts := httptest.NewServer(FileServer(Dir(".")))
 563         defer ts.Close()
 564
 565         for _, path := range []string{"/testdata/", "/testdata/index.html"} {
 566                 res, err := Get(ts.URL + path)
 567                 if err != nil {
 568                         t.Fatal(err)
 569                 }
 570                 b, err := ioutil.ReadAll(res.Body)
 571                 if err != nil {
 572                         t.Fatal("reading Body:", err)
 573                 }
 574                 if s := string(b); s != want {
 575                         t.Errorf("for path %q got %q, want %q", path, s, want)
 576                 }
 577                 res.Body.Close()
 578         }
 579 }
 580
 581 func TestFileServerZeroByte(t *testing.T) {
 582         defer afterTest(t)
 583         ts := httptest.NewServer(FileServer(Dir(".")))
 584         defer ts.Close()
 585
 586         res, err := Get(ts.URL + "/..\x00")
 587         if err != nil {
 588                 t.Fatal(err)
 589         }
 590         b, err := ioutil.ReadAll(res.Body)
 591         if err != nil {
 592                 t.Fatal("reading Body:", err)
 593         }
 594         if res.StatusCode == 200 {
 595                 t.Errorf("got status 200; want an error. Body is:\n%s", string(b))
 596         }
 597 }
 598
 599 type fakeFileInfo struct {
 600         dir      bool
 601         basename string
 602         modtime  time.Time
 603         ents     []*fakeFileInfo
 604         contents string
 605         err      error
 606 }
 607
 608 func (f *fakeFileInfo) Name() string       { return f.basename }
 609 func (f *fakeFileInfo) Sys() interface{}   { return nil }
 610 func (f *fakeFileInfo) ModTime() time.Time { return f.modtime }
 611 func (f *fakeFileInfo) IsDir() bool        { return f.dir }
 612 func (f *fakeFileInfo) Size() int64        { return int64(len(f.contents)) }
 613 func (f *fakeFileInfo) Mode() os.FileMode {
 614         if f.dir {
 615                 return 0755 | os.ModeDir
 616         }
 617         return 0644
 618 }
 619
 620 type fakeFile struct {
 621         io.ReadSeeker
 622         fi     *fakeFileInfo
 623         path   string // as opened
 624         entpos int
 625 }
 626
 627 func (f *fakeFile) Close() error               { return nil }
 628 func (f *fakeFile) Stat() (os.FileInfo, error) { return f.fi, nil }
 629 func (f *fakeFile) Readdir(count int) ([]os.FileInfo, error) {
 630         if !f.fi.dir {
 631                 return nil, os.ErrInvalid
 632         }
 633         var fis []os.FileInfo
 634
 635         limit := f.entpos + count
 636         if count <= 0 || limit > len(f.fi.ents) {
 637                 limit = len(f.fi.ents)
 638         }
 639         for ; f.entpos < limit; f.entpos++ {
 640                 fis = append(fis, f.fi.ents[f.entpos])
 641         }
 642
 643         if len(fis) == 0 && count > 0 {
 644                 return fis, io.EOF
 645         } else {
 646                 return fis, nil
 647         }
 648 }
 649
 650 type fakeFS map[string]*fakeFileInfo
 651
 652 func (fs fakeFS) Open(name string) (File, error) {
 653         name = path.Clean(name)
 654         f, ok := fs[name]
 655         if !ok {
 656                 return nil, os.ErrNotExist
 657         }
 658         if f.err != nil {
 659                 return nil, f.err
 660         }
 661         return &fakeFile{ReadSeeker: strings.NewReader(f.contents), fi: f, path: name}, nil
 662 }
 663
 664 func TestDirectoryIfNotModified(t *testing.T) {
 665         defer afterTest(t)
 666         const indexContents = "I am a fake index.html file"
 667         fileMod := time.Unix(1000000000, 0).UTC()
 668         fileModStr := fileMod.Format(TimeFormat)
 669         dirMod := time.Unix(123, 0).UTC()
 670         indexFile := &fakeFileInfo{
 671                 basename: "index.html",
 672                 modtime:  fileMod,
 673                 contents: indexContents,
 674         }
 675         fs := fakeFS{
 676                 "/": &fakeFileInfo{
 677                         dir:     true,
 678                         modtime: dirMod,
 679                         ents:    []*fakeFileInfo{indexFile},
 680                 },
 681                 "/index.html": indexFile,
 682         }
 683
 684         ts := httptest.NewServer(FileServer(fs))
 685         defer ts.Close()
 686
 687         res, err := Get(ts.URL)
 688         if err != nil {
 689                 t.Fatal(err)
 690         }
 691         b, err := ioutil.ReadAll(res.Body)
 692         if err != nil {
 693                 t.Fatal(err)
 694         }
 695         if string(b) != indexContents {
 696                 t.Fatalf("Got body %q; want %q", b, indexContents)
 697         }
 698         res.Body.Close()
 699
 700         lastMod := res.Header.Get("Last-Modified")
 701         if lastMod != fileModStr {
 702                 t.Fatalf("initial Last-Modified = %q; want %q", lastMod, fileModStr)
 703         }
 704
 705         req, _ := NewRequest("GET", ts.URL, nil)
 706         req.Header.Set("If-Modified-Since", lastMod)
 707
 708         c := ts.Client()
 709         res, err = c.Do(req)
 710         if err != nil {
 711                 t.Fatal(err)
 712         }
 713         if res.StatusCode != 304 {
 714                 t.Fatalf("Code after If-Modified-Since request = %v; want 304", res.StatusCode)
 715         }
 716         res.Body.Close()
 717
 718         // Advance the index.html file's modtime, but not the directory's.
 719         indexFile.modtime = indexFile.modtime.Add(1 * time.Hour)
 720
 721         res, err = c.Do(req)
 722         if err != nil {
 723                 t.Fatal(err)
 724         }
 725         if res.StatusCode != 200 {
 726                 t.Fatalf("Code after second If-Modified-Since request = %v; want 200; res is %#v", res.StatusCode, res)
 727         }
 728         res.Body.Close()
 729 }
 730
 731 func mustStat(t *testing.T, fileName string) os.FileInfo {
 732         fi, err := os.Stat(fileName)
 733         if err != nil {
 734                 t.Fatal(err)
 735         }
 736         return fi
 737 }
 738
 739 func TestServeContent(t *testing.T) {
 740         defer afterTest(t)
 741         type serveParam struct {
 742                 name        string
 743                 modtime     time.Time
 744                 content     io.ReadSeeker
 745                 contentType string
 746                 etag        string
 747         }
 748         servec := make(chan serveParam, 1)
 749         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 750                 p := <-servec
 751                 if p.etag != "" {
 752                         w.Header().Set("ETag", p.etag)
 753                 }
 754                 if p.contentType != "" {
 755                         w.Header().Set("Content-Type", p.contentType)
 756                 }
 757                 ServeContent(w, r, p.name, p.modtime, p.content)
 758         }))
 759         defer ts.Close()
 760
 761         type testCase struct {
 762                 // One of file or content must be set:
 763                 file    string
 764                 content io.ReadSeeker
 765
 766                 modtime          time.Time
 767                 serveETag        string // optional
 768                 serveContentType string // optional
 769                 reqHeader        map[string]string
 770                 wantLastMod      string
 771                 wantContentType  string
 772                 wantContentRange string
 773                 wantStatus       int
 774         }
 775         htmlModTime := mustStat(t, "testdata/index.html").ModTime()
 776         tests := map[string]testCase{
 777                 "no_last_modified": {
 778                         file:            "testdata/style.css",
 779                         wantContentType: "text/css; charset=utf-8",
 780                         wantStatus:      200,
 781                 },
 782                 "with_last_modified": {
 783                         file:            "testdata/index.html",
 784                         wantContentType: "text/html; charset=utf-8",
 785                         modtime:         htmlModTime,
 786                         wantLastMod:     htmlModTime.UTC().Format(TimeFormat),
 787                         wantStatus:      200,
 788                 },
 789                 "not_modified_modtime": {
 790                         file:      "testdata/style.css",
 791                         serveETag: `"foo"`, // Last-Modified sent only when no ETag
 792                         modtime:   htmlModTime,
 793                         reqHeader: map[string]string{
 794                                 "If-Modified-Since": htmlModTime.UTC().Format(TimeFormat),
 795                         },
 796                         wantStatus: 304,
 797                 },
 798                 "not_modified_modtime_with_contenttype": {
 799                         file:             "testdata/style.css",
 800                         serveContentType: "text/css", // explicit content type
 801                         serveETag:        `"foo"`,    // Last-Modified sent only when no ETag
 802                         modtime:          htmlModTime,
 803                         reqHeader: map[string]string{
 804                                 "If-Modified-Since": htmlModTime.UTC().Format(TimeFormat),
 805                         },
 806                         wantStatus: 304,
 807                 },
 808                 "not_modified_etag": {
 809                         file:      "testdata/style.css",
 810                         serveETag: `"foo"`,
 811                         reqHeader: map[string]string{
 812                                 "If-None-Match": `"foo"`,
 813                         },
 814                         wantStatus: 304,
 815                 },
 816                 "not_modified_etag_no_seek": {
 817                         content:   panicOnSeek{nil}, // should never be called
 818                         serveETag: `W/"foo"`,        // If-None-Match uses weak ETag comparison
 819                         reqHeader: map[string]string{
 820                                 "If-None-Match": `"baz", W/"foo"`,
 821                         },
 822                         wantStatus: 304,
 823                 },
 824                 "if_none_match_mismatch": {
 825                         file:      "testdata/style.css",
 826                         serveETag: `"foo"`,
 827                         reqHeader: map[string]string{
 828                                 "If-None-Match": `"Foo"`,
 829                         },
 830                         wantStatus:      200,
 831                         wantContentType: "text/css; charset=utf-8",
 832                 },
 833                 "range_good": {
 834                         file:      "testdata/style.css",
 835                         serveETag: `"A"`,
 836                         reqHeader: map[string]string{
 837                                 "Range": "bytes=0-4",
 838                         },
 839                         wantStatus:       StatusPartialContent,
 840                         wantContentType:  "text/css; charset=utf-8",
 841                         wantContentRange: "bytes 0-4/8",
 842                 },
 843                 "range_match": {
 844                         file:      "testdata/style.css",
 845                         serveETag: `"A"`,
 846                         reqHeader: map[string]string{
 847                                 "Range":    "bytes=0-4",
 848                                 "If-Range": `"A"`,
 849                         },
 850                         wantStatus:       StatusPartialContent,
 851                         wantContentType:  "text/css; charset=utf-8",
 852                         wantContentRange: "bytes 0-4/8",
 853                 },
 854                 "range_match_weak_etag": {
 855                         file:      "testdata/style.css",
 856                         serveETag: `W/"A"`,
 857                         reqHeader: map[string]string{
 858                                 "Range":    "bytes=0-4",
 859                                 "If-Range": `W/"A"`,
 860                         },
 861                         wantStatus:      200,
 862                         wantContentType: "text/css; charset=utf-8",
 863                 },
 864                 "range_no_overlap": {
 865                         file:      "testdata/style.css",
 866                         serveETag: `"A"`,
 867                         reqHeader: map[string]string{
 868                                 "Range": "bytes=10-20",
 869                         },
 870                         wantStatus:       StatusRequestedRangeNotSatisfiable,
 871                         wantContentType:  "text/plain; charset=utf-8",
 872                         wantContentRange: "bytes */8",
 873                 },
 874                 // An If-Range resource for entity "A", but entity "B" is now current.
 875                 // The Range request should be ignored.
 876                 "range_no_match": {
 877                         file:      "testdata/style.css",
 878                         serveETag: `"A"`,
 879                         reqHeader: map[string]string{
 880                                 "Range":    "bytes=0-4",
 881                                 "If-Range": `"B"`,
 882                         },
 883                         wantStatus:      200,
 884                         wantContentType: "text/css; charset=utf-8",
 885                 },
 886                 "range_with_modtime": {
 887                         file:    "testdata/style.css",
 888                         modtime: time.Date(2014, 6, 25, 17, 12, 18, 0 /* nanos */, time.UTC),
 889                         reqHeader: map[string]string{
 890                                 "Range":    "bytes=0-4",
 891                                 "If-Range": "Wed, 25 Jun 2014 17:12:18 GMT",
 892                         },
 893                         wantStatus:       StatusPartialContent,
 894                         wantContentType:  "text/css; charset=utf-8",
 895                         wantContentRange: "bytes 0-4/8",
 896                         wantLastMod:      "Wed, 25 Jun 2014 17:12:18 GMT",
 897                 },
 898                 "range_with_modtime_nanos": {
 899                         file:    "testdata/style.css",
 900                         modtime: time.Date(2014, 6, 25, 17, 12, 18, 123 /* nanos */, time.UTC),
 901                         reqHeader: map[string]string{
 902                                 "Range":    "bytes=0-4",
 903                                 "If-Range": "Wed, 25 Jun 2014 17:12:18 GMT",
 904                         },
 905                         wantStatus:       StatusPartialContent,
 906                         wantContentType:  "text/css; charset=utf-8",
 907                         wantContentRange: "bytes 0-4/8",
 908                         wantLastMod:      "Wed, 25 Jun 2014 17:12:18 GMT",
 909                 },
 910                 "unix_zero_modtime": {
 911                         content:         strings.NewReader("<html>foo"),
 912                         modtime:         time.Unix(0, 0),
 913                         wantStatus:      StatusOK,
 914                         wantContentType: "text/html; charset=utf-8",
 915                 },
 916                 "ifmatch_matches": {
 917                         file:      "testdata/style.css",
 918                         serveETag: `"A"`,
 919                         reqHeader: map[string]string{
 920                                 "If-Match": `"Z", "A"`,
 921                         },
 922                         wantStatus:      200,
 923                         wantContentType: "text/css; charset=utf-8",
 924                 },
 925                 "ifmatch_star": {
 926                         file:      "testdata/style.css",
 927                         serveETag: `"A"`,
 928                         reqHeader: map[string]string{
 929                                 "If-Match": `*`,
 930                         },
 931                         wantStatus:      200,
 932                         wantContentType: "text/css; charset=utf-8",
 933                 },
 934                 "ifmatch_failed": {
 935                         file:      "testdata/style.css",
 936                         serveETag: `"A"`,
 937                         reqHeader: map[string]string{
 938                                 "If-Match": `"B"`,
 939                         },
 940                         wantStatus:      412,
 941                         wantContentType: "text/plain; charset=utf-8",
 942                 },
 943                 "ifmatch_fails_on_weak_etag": {
 944                         file:      "testdata/style.css",
 945                         serveETag: `W/"A"`,
 946                         reqHeader: map[string]string{
 947                                 "If-Match": `W/"A"`,
 948                         },
 949                         wantStatus:      412,
 950                         wantContentType: "text/plain; charset=utf-8",
 951                 },
 952                 "if_unmodified_since_true": {
 953                         file:    "testdata/style.css",
 954                         modtime: htmlModTime,
 955                         reqHeader: map[string]string{
 956                                 "If-Unmodified-Since": htmlModTime.UTC().Format(TimeFormat),
 957                         },
 958                         wantStatus:      200,
 959                         wantContentType: "text/css; charset=utf-8",
 960                         wantLastMod:     htmlModTime.UTC().Format(TimeFormat),
 961                 },
 962                 "if_unmodified_since_false": {
 963                         file:    "testdata/style.css",
 964                         modtime: htmlModTime,
 965                         reqHeader: map[string]string{
 966                                 "If-Unmodified-Since": htmlModTime.Add(-2 * time.Second).UTC().Format(TimeFormat),
 967                         },
 968                         wantStatus:      412,
 969                         wantContentType: "text/plain; charset=utf-8",
 970                         wantLastMod:     htmlModTime.UTC().Format(TimeFormat),
 971                 },
 972         }
 973         for testName, tt := range tests {
 974                 var content io.ReadSeeker
 975                 if tt.file != "" {
 976                         f, err := os.Open(tt.file)
 977                         if err != nil {
 978                                 t.Fatalf("test %q: %v", testName, err)
 979                         }
 980                         defer f.Close()
 981                         content = f
 982                 } else {
 983                         content = tt.content
 984                 }
 985
 986                 servec <- serveParam{
 987                         name:        filepath.Base(tt.file),
 988                         content:     content,
 989                         modtime:     tt.modtime,
 990                         etag:        tt.serveETag,
 991                         contentType: tt.serveContentType,
 992                 }
 993                 req, err := NewRequest("GET", ts.URL, nil)
 994                 if err != nil {
 995                         t.Fatal(err)
 996                 }
 997                 for k, v := range tt.reqHeader {
 998                         req.Header.Set(k, v)
 999                 }
1000
1001                 c := ts.Client()
1002                 res, err := c.Do(req)
1003                 if err != nil {
1004                         t.Fatal(err)
1005                 }
1006                 io.Copy(ioutil.Discard, res.Body)
1007                 res.Body.Close()
1008                 if res.StatusCode != tt.wantStatus {
1009                         t.Errorf("test %q: status = %d; want %d", testName, res.StatusCode, tt.wantStatus)
1010                 }
1011                 if g, e := res.Header.Get("Content-Type"), tt.wantContentType; g != e {
1012                         t.Errorf("test %q: content-type = %q, want %q", testName, g, e)
1013                 }
1014                 if g, e := res.Header.Get("Content-Range"), tt.wantContentRange; g != e {
1015                         t.Errorf("test %q: content-range = %q, want %q", testName, g, e)
1016                 }
1017                 if g, e := res.Header.Get("Last-Modified"), tt.wantLastMod; g != e {
1018                         t.Errorf("test %q: last-modified = %q, want %q", testName, g, e)
1019                 }
1020         }
1021 }
1022
1023 // Issue 12991
1024 func TestServerFileStatError(t *testing.T) {
1025         rec := httptest.NewRecorder()
1026         r, _ := NewRequest("GET", "http://foo/", nil)
1027         redirect := false
1028         name := "file.txt"
1029         fs := issue12991FS{}
1030         ExportServeFile(rec, r, fs, name, redirect)
1031         if body := rec.Body.String(); !strings.Contains(body, "403") || !strings.Contains(body, "Forbidden") {
1032                 t.Errorf("wanted 403 forbidden message; got: %s", body)
1033         }
1034 }
1035
1036 type issue12991FS struct{}
1037
1038 func (issue12991FS) Open(string) (File, error) { return issue12991File{}, nil }
1039
1040 type issue12991File struct{ File }
1041
1042 func (issue12991File) Stat() (os.FileInfo, error) { return nil, os.ErrPermission }
1043 func (issue12991File) Close() error               { return nil }
1044
1045 func TestServeContentErrorMessages(t *testing.T) {
1046         defer afterTest(t)
1047         fs := fakeFS{
1048                 "/500": &fakeFileInfo{
1049                         err: errors.New("random error"),
1050                 },
1051                 "/403": &fakeFileInfo{
1052                         err: &os.PathError{Err: os.ErrPermission},
1053                 },
1054         }
1055         ts := httptest.NewServer(FileServer(fs))
1056         defer ts.Close()
1057         c := ts.Client()
1058         for _, code := range []int{403, 404, 500} {
1059                 res, err := c.Get(fmt.Sprintf("%s/%d", ts.URL, code))
1060                 if err != nil {
1061                         t.Errorf("Error fetching /%d: %v", code, err)
1062                         continue
1063                 }
1064                 if res.StatusCode != code {
1065                         t.Errorf("For /%d, status code = %d; want %d", code, res.StatusCode, code)
1066                 }
1067                 res.Body.Close()
1068         }
1069 }
1070
1071 // verifies that sendfile is being used on Linux
1072 func TestLinuxSendfile(t *testing.T) {
1073         setParallel(t)
1074         defer afterTest(t)
1075         if runtime.GOOS != "linux" {
1076                 t.Skip("skipping; linux-only test")
1077         }
1078         if _, err := exec.LookPath("strace"); err != nil {
1079                 t.Skip("skipping; strace not found in path")
1080         }
1081
1082         ln, err := net.Listen("tcp", "127.0.0.1:0")
1083         if err != nil {
1084                 t.Fatal(err)
1085         }
1086         lnf, err := ln.(*net.TCPListener).File()
1087         if err != nil {
1088                 t.Fatal(err)
1089         }
1090         defer ln.Close()
1091
1092         syscalls := "sendfile,sendfile64"
1093         switch runtime.GOARCH {
1094         case "mips64", "mips64le", "s390x", "alpha":
1095                 // strace on the above platforms doesn't support sendfile64
1096                 // and will error out if we specify that with `-e trace='.
1097                 syscalls = "sendfile"
1098         }
1099
1100         // Attempt to run strace, and skip on failure - this test requires SYS_PTRACE.
1101         if err := exec.Command("strace", "-f", "-q", "-e", "trace="+syscalls, os.Args[0], "-test.run=^$").Run(); err != nil {
1102                 t.Skipf("skipping; failed to run strace: %v", err)
1103         }
1104
1105         var buf bytes.Buffer
1106         child := exec.Command("strace", "-f", "-q", "-e", "trace="+syscalls, os.Args[0], "-test.run=TestLinuxSendfileChild")
1107         child.ExtraFiles = append(child.ExtraFiles, lnf)
1108         child.Env = append([]string{"GO_WANT_HELPER_PROCESS=1"}, os.Environ()...)
1109         child.Stdout = &buf
1110         child.Stderr = &buf
1111         if err := child.Start(); err != nil {
1112                 t.Skipf("skipping; failed to start straced child: %v", err)
1113         }
1114
1115         res, err := Get(fmt.Sprintf("http://%s/", ln.Addr()))
1116         if err != nil {
1117                 t.Fatalf("http client error: %v", err)
1118         }
1119         _, err = io.Copy(ioutil.Discard, res.Body)
1120         if err != nil {
1121                 t.Fatalf("client body read error: %v", err)
1122         }
1123         res.Body.Close()
1124
1125         // Force child to exit cleanly.
1126         Post(fmt.Sprintf("http://%s/quit", ln.Addr()), "", nil)
1127         child.Wait()
1128
1129         rx := regexp.MustCompile(`sendfile(64)?\(\d+,\s*\d+,\s*NULL,\s*\d+`)
1130         out := buf.String()
1131         if !rx.MatchString(out) {
1132                 t.Errorf("no sendfile system call found in:\n%s", out)
1133         }
1134 }
1135
1136 func getBody(t *testing.T, testName string, req Request, client *Client) (*Response, []byte) {
1137         r, err := client.Do(&req)
1138         if err != nil {
1139                 t.Fatalf("%s: for URL %q, send error: %v", testName, req.URL.String(), err)
1140         }
1141         b, err := ioutil.ReadAll(r.Body)
1142         if err != nil {
1143                 t.Fatalf("%s: for URL %q, reading body: %v", testName, req.URL.String(), err)
1144         }
1145         return r, b
1146 }
1147
1148 // TestLinuxSendfileChild isn't a real test. It's used as a helper process
1149 // for TestLinuxSendfile.
1150 func TestLinuxSendfileChild(*testing.T) {
1151         if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
1152                 return
1153         }
1154         defer os.Exit(0)
1155         fd3 := os.NewFile(3, "ephemeral-port-listener")
1156         ln, err := net.FileListener(fd3)
1157         if err != nil {
1158                 panic(err)
1159         }
1160         mux := NewServeMux()
1161         mux.Handle("/", FileServer(Dir("testdata")))
1162         mux.HandleFunc("/quit", func(ResponseWriter, *Request) {
1163                 os.Exit(0)
1164         })
1165         s := &Server{Handler: mux}
1166         err = s.Serve(ln)
1167         if err != nil {
1168                 panic(err)
1169         }
1170 }
1171
1172 // Issue 18984: tests that requests for paths beyond files return not-found errors
1173 func TestFileServerNotDirError(t *testing.T) {
1174         defer afterTest(t)
1175         ts := httptest.NewServer(FileServer(Dir("testdata")))
1176         defer ts.Close()
1177
1178         res, err := Get(ts.URL + "/index.html/not-a-file")
1179         if err != nil {
1180                 t.Fatal(err)
1181         }
1182         res.Body.Close()
1183         if res.StatusCode != 404 {
1184                 t.Errorf("StatusCode = %v; want 404", res.StatusCode)
1185         }
1186
1187         test := func(name string, dir Dir) {
1188                 t.Run(name, func(t *testing.T) {
1189                         _, err = dir.Open("/index.html/not-a-file")
1190                         if err == nil {
1191                                 t.Fatal("err == nil; want != nil")
1192                         }
1193                         if !os.IsNotExist(err) {
1194                                 t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
1195                         }
1196
1197                         _, err = dir.Open("/index.html/not-a-dir/not-a-file")
1198                         if err == nil {
1199                                 t.Fatal("err == nil; want != nil")
1200                         }
1201                         if !os.IsNotExist(err) {
1202                                 t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
1203                         }
1204                 })
1205         }
1206
1207         absPath, err := filepath.Abs("testdata")
1208         if err != nil {
1209                 t.Fatal("get abs path:", err)
1210         }
1211
1212         test("RelativePath", Dir("testdata"))
1213         test("AbsolutePath", Dir(absPath))
1214 }
1215
1216 func TestFileServerCleanPath(t *testing.T) {
1217         tests := []struct {
1218                 path     string
1219                 wantCode int
1220                 wantOpen []string
1221         }{
1222                 {"/", 200, []string{"/", "/index.html"}},
1223                 {"/dir", 301, []string{"/dir"}},
1224                 {"/dir/", 200, []string{"/dir", "/dir/index.html"}},
1225         }
1226         for _, tt := range tests {
1227                 var log []string
1228                 rr := httptest.NewRecorder()
1229                 req, _ := NewRequest("GET", "http://foo.localhost"+tt.path, nil)
1230                 FileServer(fileServerCleanPathDir{&log}).ServeHTTP(rr, req)
1231                 if !reflect.DeepEqual(log, tt.wantOpen) {
1232                         t.Logf("For %s: Opens = %q; want %q", tt.path, log, tt.wantOpen)
1233                 }
1234                 if rr.Code != tt.wantCode {
1235                         t.Logf("For %s: Response code = %d; want %d", tt.path, rr.Code, tt.wantCode)
1236                 }
1237         }
1238 }
1239
1240 type fileServerCleanPathDir struct {
1241         log *[]string
1242 }
1243
1244 func (d fileServerCleanPathDir) Open(path string) (File, error) {
1245         *(d.log) = append(*(d.log), path)
1246         if path == "/" || path == "/dir" || path == "/dir/" {
1247                 // Just return back something that's a directory.
1248                 return Dir(".").Open(".")
1249         }
1250         return nil, os.ErrNotExist
1251 }
1252
1253 type panicOnSeek struct{ io.ReadSeeker }
1254
1255 func Test_scanETag(t *testing.T) {
1256         tests := []struct {
1257                 in         string
1258                 wantETag   string
1259                 wantRemain string
1260         }{
1261                 {`W/"etag-1"`, `W/"etag-1"`, ""},
1262                 {`"etag-2"`, `"etag-2"`, ""},
1263                 {`"etag-1", "etag-2"`, `"etag-1"`, `, "etag-2"`},
1264                 {"", "", ""},
1265                 {"W/", "", ""},
1266                 {`W/"truc`, "", ""},
1267                 {`w/"case-sensitive"`, "", ""},
1268                 {`"spaced etag"`, "", ""},
1269         }
1270         for _, test := range tests {
1271                 etag, remain := ExportScanETag(test.in)
1272                 if etag != test.wantETag || remain != test.wantRemain {
1273                         t.Errorf("scanETag(%q)=%q %q, want %q %q", test.in, etag, remain, test.wantETag, test.wantRemain)
1274                 }
1275         }
1276 }