github.com/joomcode/cue@v0.4.4-0.20221111115225-539fe3512047/pkg/path/path_test.go (about)

     1  // Copyright 2020 CUE Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Copyright 2009 The Go Authors. All rights reserved.
    16  // Use of this source code is governed by a BSD-style
    17  // license that can be found in the LICENSE file.
    18  
    19  package path
    20  
    21  import (
    22  	"reflect"
    23  	"runtime"
    24  	"testing"
    25  )
    26  
    27  type PathTest struct {
    28  	path, result string
    29  }
    30  
    31  var cleantests = []PathTest{
    32  	// Already clean
    33  	{"abc", "abc"},
    34  	{"abc/def", "abc/def"},
    35  	{"a/b/c", "a/b/c"},
    36  	{".", "."},
    37  	{"..", ".."},
    38  	{"../..", "../.."},
    39  	{"../../abc", "../../abc"},
    40  	{"/abc", "/abc"},
    41  	{"/", "/"},
    42  
    43  	// Empty is current dir
    44  	{"", "."},
    45  
    46  	// Remove trailing slash
    47  	{"abc/", "abc"},
    48  	{"abc/def/", "abc/def"},
    49  	{"a/b/c/", "a/b/c"},
    50  	{"./", "."},
    51  	{"../", ".."},
    52  	{"../../", "../.."},
    53  	{"/abc/", "/abc"},
    54  
    55  	// Remove doubled slash
    56  	{"abc//def//ghi", "abc/def/ghi"},
    57  	{"//abc", "/abc"},
    58  	{"///abc", "/abc"},
    59  	{"//abc//", "/abc"},
    60  	{"abc//", "abc"},
    61  
    62  	// Remove . elements
    63  	{"abc/./def", "abc/def"},
    64  	{"/./abc/def", "/abc/def"},
    65  	{"abc/.", "abc"},
    66  
    67  	// Remove .. elements
    68  	{"abc/def/ghi/../jkl", "abc/def/jkl"},
    69  	{"abc/def/../ghi/../jkl", "abc/jkl"},
    70  	{"abc/def/..", "abc"},
    71  	{"abc/def/../..", "."},
    72  	{"/abc/def/../..", "/"},
    73  	{"abc/def/../../..", ".."},
    74  	{"/abc/def/../../..", "/"},
    75  	{"abc/def/../../../ghi/jkl/../../../mno", "../../mno"},
    76  	{"/../abc", "/abc"},
    77  
    78  	// Combinations
    79  	{"abc/./../def", "def"},
    80  	{"abc//./../def", "def"},
    81  	{"abc/../../././../def", "../../def"},
    82  }
    83  
    84  var wincleantests = []PathTest{
    85  	{`c:`, `c:.`},
    86  	{`c:\`, `c:\`},
    87  	{`c:\abc`, `c:\abc`},
    88  	{`c:abc\..\..\.\.\..\def`, `c:..\..\def`},
    89  	{`c:\abc\def\..\..`, `c:\`},
    90  	{`c:\..\abc`, `c:\abc`},
    91  	{`c:..\abc`, `c:..\abc`},
    92  	{`\`, `\`},
    93  	{`/`, `\`},
    94  	{`\\i\..\c$`, `\c$`},
    95  	{`\\i\..\i\c$`, `\i\c$`},
    96  	{`\\i\..\I\c$`, `\I\c$`},
    97  	{`\\host\share\foo\..\bar`, `\\host\share\bar`},
    98  	{`//host/share/foo/../baz`, `\\host\share\baz`},
    99  	{`\\a\b\..\c`, `\\a\b\c`},
   100  	{`\\a\b`, `\\a\b`},
   101  }
   102  
   103  func TestClean(t *testing.T) {
   104  	tests := cleantests
   105  	for _, os := range []OS{Unix, Windows, Plan9} {
   106  		if os == Windows {
   107  			for i := range tests {
   108  				tests[i].result = FromSlash(tests[i].result, os)
   109  			}
   110  			tests = append(tests, wincleantests...)
   111  		}
   112  		for _, test := range tests {
   113  			if s := Clean(test.path, os); s != test.result {
   114  				t.Errorf("Clean(%q) = %q, want %q", test.path, s, test.result)
   115  			}
   116  			if s := Clean(test.result, os); s != test.result {
   117  				t.Errorf("Clean(%q) = %q, want %q", test.result, s, test.result)
   118  			}
   119  		}
   120  
   121  		if testing.Short() {
   122  			t.Skip("skipping malloc count in short mode")
   123  		}
   124  		if runtime.GOMAXPROCS(0) > 1 {
   125  			t.Log("skipping AllocsPerRun checks; GOMAXPROCS>1")
   126  			return
   127  		}
   128  
   129  		for _, test := range tests {
   130  			allocs := testing.AllocsPerRun(100, func() { Clean(test.result, os) })
   131  			if allocs > 0 {
   132  				t.Errorf("Clean(%q): %v allocs, want zero", test.result, allocs)
   133  			}
   134  		}
   135  	}
   136  }
   137  
   138  func TestFromAndToSlash(t *testing.T) {
   139  	for _, o := range []OS{Unix, Windows, Plan9} {
   140  		sep := getOS(o).Separator
   141  
   142  		var slashtests = []PathTest{
   143  			{"", ""},
   144  			{"/", string(sep)},
   145  			{"/a/b", string([]byte{sep, 'a', sep, 'b'})},
   146  			{"a//b", string([]byte{'a', sep, sep, 'b'})},
   147  		}
   148  
   149  		for _, test := range slashtests {
   150  			if s := FromSlash(test.path, o); s != test.result {
   151  				t.Errorf("FromSlash(%q) = %q, want %q", test.path, s, test.result)
   152  			}
   153  			if s := ToSlash(test.result, o); s != test.path {
   154  				t.Errorf("ToSlash(%q) = %q, want %q", test.result, s, test.path)
   155  			}
   156  		}
   157  	}
   158  }
   159  
   160  type SplitListTest struct {
   161  	list   string
   162  	result []string
   163  }
   164  
   165  var winsplitlisttests = []SplitListTest{
   166  	// quoted
   167  	{`"a"`, []string{`a`}},
   168  
   169  	// semicolon
   170  	{`";"`, []string{`;`}},
   171  	{`"a;b"`, []string{`a;b`}},
   172  	{`";";`, []string{`;`, ``}},
   173  	{`;";"`, []string{``, `;`}},
   174  
   175  	// partially quoted
   176  	{`a";"b`, []string{`a;b`}},
   177  	{`a; ""b`, []string{`a`, ` b`}},
   178  	{`"a;b`, []string{`a;b`}},
   179  	{`""a;b`, []string{`a`, `b`}},
   180  	{`"""a;b`, []string{`a;b`}},
   181  	{`""""a;b`, []string{`a`, `b`}},
   182  	{`a";b`, []string{`a;b`}},
   183  	{`a;b";c`, []string{`a`, `b;c`}},
   184  	{`"a";b";c`, []string{`a`, `b;c`}},
   185  }
   186  
   187  func TestSplitList(t *testing.T) {
   188  	for _, os := range []OS{Unix, Windows, Plan9} {
   189  		sep := getOS(os).ListSeparator
   190  
   191  		tests := []SplitListTest{
   192  			{"", []string{}},
   193  			{string([]byte{'a', sep, 'b'}), []string{"a", "b"}},
   194  			{string([]byte{sep, 'a', sep, 'b'}), []string{"", "a", "b"}},
   195  		}
   196  		if os == Windows {
   197  			tests = append(tests, winsplitlisttests...)
   198  		}
   199  		for _, test := range tests {
   200  			if l := SplitList(test.list, os); !reflect.DeepEqual(l, test.result) {
   201  				t.Errorf("SplitList(%#q, %q) = %#q, want %#q", test.list, os, l, test.result)
   202  			}
   203  		}
   204  	}
   205  }
   206  
   207  type SplitTest struct {
   208  	path, dir, file string
   209  }
   210  
   211  var unixsplittests = []SplitTest{
   212  	{"a/b", "a/", "b"},
   213  	{"a/b/", "a/b/", ""},
   214  	{"a/", "a/", ""},
   215  	{"a", "", "a"},
   216  	{"/", "/", ""},
   217  }
   218  
   219  var winsplittests = []SplitTest{
   220  	{`c:`, `c:`, ``},
   221  	{`c:/`, `c:/`, ``},
   222  	{`c:/foo`, `c:/`, `foo`},
   223  	{`c:/foo/bar`, `c:/foo/`, `bar`},
   224  	{`//host/share`, `//host/share`, ``},
   225  	{`//host/share/`, `//host/share/`, ``},
   226  	{`//host/share/foo`, `//host/share/`, `foo`},
   227  	{`\\host\share`, `\\host\share`, ``},
   228  	{`\\host\share\`, `\\host\share\`, ``},
   229  	{`\\host\share\foo`, `\\host\share\`, `foo`},
   230  }
   231  
   232  func TestSplit(t *testing.T) {
   233  	for _, os := range []OS{Windows, Unix} {
   234  		var splittests []SplitTest
   235  		splittests = unixsplittests
   236  		if os == Windows {
   237  			splittests = append(splittests, winsplittests...)
   238  		}
   239  		for _, test := range splittests {
   240  			pair := Split(test.path, os)
   241  			d, f := pair[0], pair[1]
   242  			if d != test.dir || f != test.file {
   243  				t.Errorf("Split(%q, %q) = %q, %q, want %q, %q",
   244  					test.path, os, d, f, test.dir, test.file)
   245  			}
   246  		}
   247  	}
   248  }
   249  
   250  type JoinTest struct {
   251  	elem []string
   252  	path string
   253  }
   254  
   255  var jointests = []JoinTest{
   256  	// zero parameters
   257  	{[]string{}, ""},
   258  
   259  	// one parameter
   260  	{[]string{""}, ""},
   261  	{[]string{"/"}, "/"},
   262  	{[]string{"a"}, "a"},
   263  
   264  	// two parameters
   265  	{[]string{"a", "b"}, "a/b"},
   266  	{[]string{"a", ""}, "a"},
   267  	{[]string{"", "b"}, "b"},
   268  	{[]string{"/", "a"}, "/a"},
   269  	{[]string{"/", "a/b"}, "/a/b"},
   270  	{[]string{"/", ""}, "/"},
   271  	{[]string{"//", "a"}, "/a"},
   272  	{[]string{"/a", "b"}, "/a/b"},
   273  	{[]string{"a/", "b"}, "a/b"},
   274  	{[]string{"a/", ""}, "a"},
   275  	{[]string{"", ""}, ""},
   276  
   277  	// three parameters
   278  	{[]string{"/", "a", "b"}, "/a/b"},
   279  }
   280  
   281  var winjointests = []JoinTest{
   282  	{[]string{`directory`, `file`}, `directory\file`},
   283  	{[]string{`C:\Windows\`, `System32`}, `C:\Windows\System32`},
   284  	{[]string{`C:\Windows\`, ``}, `C:\Windows`},
   285  	{[]string{`C:\`, `Windows`}, `C:\Windows`},
   286  	{[]string{`C:`, `a`}, `C:a`},
   287  	{[]string{`C:`, `a\b`}, `C:a\b`},
   288  	{[]string{`C:`, `a`, `b`}, `C:a\b`},
   289  	{[]string{`C:`, ``, `b`}, `C:b`},
   290  	{[]string{`C:`, ``, ``, `b`}, `C:b`},
   291  	{[]string{`C:`, ``}, `C:.`},
   292  	{[]string{`C:`, ``, ``}, `C:.`},
   293  	{[]string{`C:.`, `a`}, `C:a`},
   294  	{[]string{`C:a`, `b`}, `C:a\b`},
   295  	{[]string{`C:a`, `b`, `d`}, `C:a\b\d`},
   296  	{[]string{`\\host\share`, `foo`}, `\\host\share\foo`},
   297  	{[]string{`\\host\share\foo`}, `\\host\share\foo`},
   298  	{[]string{`//host/share`, `foo/bar`}, `\\host\share\foo\bar`},
   299  	{[]string{`\`}, `\`},
   300  	{[]string{`\`, ``}, `\`},
   301  	{[]string{`\`, `a`}, `\a`},
   302  	{[]string{`\\`, `a`}, `\a`},
   303  	{[]string{`\`, `a`, `b`}, `\a\b`},
   304  	{[]string{`\\`, `a`, `b`}, `\a\b`},
   305  	{[]string{`\`, `\\a\b`, `c`}, `\a\b\c`},
   306  	{[]string{`\\a`, `b`, `c`}, `\a\b\c`},
   307  	{[]string{`\\a\`, `b`, `c`}, `\a\b\c`},
   308  }
   309  
   310  func TestJoin(t *testing.T) {
   311  	for _, os := range []OS{Unix, Windows} {
   312  		if os == Windows {
   313  			jointests = append(jointests, winjointests...)
   314  		}
   315  		for _, test := range jointests {
   316  			expected := FromSlash(test.path, os)
   317  			if p := Join(test.elem, os); p != expected {
   318  				t.Errorf("join(%q, %q) = %q, want %q", test.elem, os, p, expected)
   319  			}
   320  		}
   321  	}
   322  }
   323  
   324  type ExtTest struct {
   325  	path, ext string
   326  }
   327  
   328  var exttests = []ExtTest{
   329  	{"path.go", ".go"},
   330  	{"path.pb.go", ".go"},
   331  	{"a.dir/b", ""},
   332  	{"a.dir/b.go", ".go"},
   333  	{"a.dir/", ""},
   334  }
   335  
   336  func TestExt(t *testing.T) {
   337  	for _, os := range []OS{Unix, Windows} {
   338  		for _, test := range exttests {
   339  			if x := Ext(test.path, os); x != test.ext {
   340  				t.Errorf("Ext(%q, %q) = %q, want %q", test.path, os, x, test.ext)
   341  			}
   342  		}
   343  	}
   344  }
   345  
   346  var basetests = []PathTest{
   347  	{"", "."},
   348  	{".", "."},
   349  	{"/.", "."},
   350  	{"/", "/"},
   351  	{"////", "/"},
   352  	{"x/", "x"},
   353  	{"abc", "abc"},
   354  	{"abc/def", "def"},
   355  	{"a/b/.x", ".x"},
   356  	{"a/b/c.", "c."},
   357  	{"a/b/c.x", "c.x"},
   358  }
   359  
   360  var winbasetests = []PathTest{
   361  	{`c:\`, `\`},
   362  	{`c:.`, `.`},
   363  	{`c:\a\b`, `b`},
   364  	{`c:a\b`, `b`},
   365  	{`c:a\b\c`, `c`},
   366  	{`\\host\share\`, `\`},
   367  	{`\\host\share\a`, `a`},
   368  	{`\\host\share\a\b`, `b`},
   369  }
   370  
   371  func TestBase(t *testing.T) {
   372  	tests := basetests
   373  	for _, os := range []OS{Unix, Windows} {
   374  		if os == Windows {
   375  			// make unix tests work on windows
   376  			for i := range tests {
   377  				tests[i].result = Clean(tests[i].result, os)
   378  			}
   379  			// add windows specific tests
   380  			tests = append(tests, winbasetests...)
   381  		}
   382  		for _, test := range tests {
   383  			if s := Base(test.path, os); s != test.result {
   384  				t.Errorf("Base(%q, %q) = %q, want %q", test.path, os, s, test.result)
   385  			}
   386  		}
   387  	}
   388  }
   389  
   390  var dirtests = []PathTest{
   391  	{"", "."},
   392  	{".", "."},
   393  	{"/.", "/"},
   394  	{"/", "/"},
   395  	{"////", "/"},
   396  	{"/foo", "/"},
   397  	{"x/", "x"},
   398  	{"abc", "."},
   399  	{"abc/def", "abc"},
   400  	{"a/b/.x", "a/b"},
   401  	{"a/b/c.", "a/b"},
   402  	{"a/b/c.x", "a/b"},
   403  }
   404  
   405  var windirtests = []PathTest{
   406  	{`c:\`, `c:\`},
   407  	{`c:.`, `c:.`},
   408  	{`c:\a\b`, `c:\a`},
   409  	{`c:a\b`, `c:a`},
   410  	{`c:a\b\c`, `c:a\b`},
   411  	{`\\host\share`, `\\host\share`},
   412  	{`\\host\share\`, `\\host\share\`},
   413  	{`\\host\share\a`, `\\host\share\`},
   414  	{`\\host\share\a\b`, `\\host\share\a`},
   415  }
   416  
   417  func TestDir(t *testing.T) {
   418  	for _, os := range []OS{Unix, Windows} {
   419  		tests := dirtests
   420  		if os == Windows {
   421  			// make unix tests work on windows
   422  			for i := range tests {
   423  				tests[i].result = Clean(tests[i].result, os)
   424  			}
   425  			// add windows specific tests
   426  			tests = append(tests, windirtests...)
   427  		}
   428  		for _, test := range tests {
   429  			if s := Dir(test.path, os); s != test.result {
   430  				t.Errorf("Dir(%q, %q) = %q, want %q", test.path, os, s, test.result)
   431  			}
   432  		}
   433  	}
   434  }
   435  
   436  type IsAbsTest struct {
   437  	path  string
   438  	isAbs bool
   439  }
   440  
   441  var isabstests = []IsAbsTest{
   442  	{"", false},
   443  	{"/", true},
   444  	{"/usr/bin/gcc", true},
   445  	{"..", false},
   446  	{"/a/../bb", true},
   447  	{".", false},
   448  	{"./", false},
   449  	{"lala", false},
   450  }
   451  
   452  var winisabstests = []IsAbsTest{
   453  	{`C:\`, true},
   454  	{`c\`, false},
   455  	{`c::`, false},
   456  	{`c:`, false},
   457  	{`/`, false},
   458  	{`\`, false},
   459  	{`\Windows`, false},
   460  	{`c:a\b`, false},
   461  	{`c:\a\b`, true},
   462  	{`c:/a/b`, true},
   463  	{`\\host\share\foo`, true},
   464  	{`//host/share/foo/bar`, true},
   465  }
   466  
   467  func TestIsAbs(t *testing.T) {
   468  	for _, os := range []OS{Unix, Windows} {
   469  		var tests []IsAbsTest
   470  		if os == Windows {
   471  			tests = append(tests, winisabstests...)
   472  			// All non-windows tests should fail, because they have no volume letter.
   473  			for _, test := range isabstests {
   474  				tests = append(tests, IsAbsTest{test.path, false})
   475  			}
   476  			// All non-windows test should work as intended if prefixed with volume letter.
   477  			for _, test := range isabstests {
   478  				tests = append(tests, IsAbsTest{"c:" + test.path, test.isAbs})
   479  			}
   480  			// Test reserved names.
   481  			// tests = append(tests, IsAbsTest{"/dev/null", true})
   482  			tests = append(tests, IsAbsTest{"NUL", true})
   483  			tests = append(tests, IsAbsTest{"nul", true})
   484  			tests = append(tests, IsAbsTest{"CON", true})
   485  		} else {
   486  			tests = isabstests
   487  		}
   488  
   489  		for _, test := range tests {
   490  			if r := IsAbs(test.path, os); r != test.isAbs {
   491  				t.Errorf("IsAbs(%q, %q) = %v, want %v", test.path, os, r, test.isAbs)
   492  			}
   493  		}
   494  	}
   495  }
   496  
   497  // // simpleJoin builds a file name from the directory and path.
   498  // // It does not use Join because we don't want ".." to be evaluated.
   499  // func simpleJoin(dir, path string) string {
   500  // 	return dir + string(Separator) + path
   501  // }
   502  
   503  // Test directories relative to temporary directory.
   504  // The tests are run in absTestDirs[0].
   505  var absTestDirs = []string{
   506  	"a",
   507  	"a/b",
   508  	"a/b/c",
   509  }
   510  
   511  // Test paths relative to temporary directory. $ expands to the directory.
   512  // The tests are run in absTestDirs[0].
   513  // We create absTestDirs first.
   514  var absTests = []string{
   515  	".",
   516  	"b",
   517  	"b/",
   518  	"../a",
   519  	"../a/b",
   520  	"../a/b/./c/../../.././a",
   521  	"../a/b/./c/../../.././a/",
   522  	"$",
   523  	"$/.",
   524  	"$/a/../a/b",
   525  	"$/a/b/c/../../.././a",
   526  	"$/a/b/c/../../.././a/",
   527  }
   528  
   529  type RelTests struct {
   530  	root, path, want string
   531  }
   532  
   533  var reltests = []RelTests{
   534  	{"a/b", "a/b", "."},
   535  	{"a/b/.", "a/b", "."},
   536  	{"a/b", "a/b/.", "."},
   537  	{"./a/b", "a/b", "."},
   538  	{"a/b", "./a/b", "."},
   539  	{"ab/cd", "ab/cde", "../cde"},
   540  	{"ab/cd", "ab/c", "../c"},
   541  	{"a/b", "a/b/c/d", "c/d"},
   542  	{"a/b", "a/b/../c", "../c"},
   543  	{"a/b/../c", "a/b", "../b"},
   544  	{"a/b/c", "a/c/d", "../../c/d"},
   545  	{"a/b", "c/d", "../../c/d"},
   546  	{"a/b/c/d", "a/b", "../.."},
   547  	{"a/b/c/d", "a/b/", "../.."},
   548  	{"a/b/c/d/", "a/b", "../.."},
   549  	{"a/b/c/d/", "a/b/", "../.."},
   550  	{"../../a/b", "../../a/b/c/d", "c/d"},
   551  	{"/a/b", "/a/b", "."},
   552  	{"/a/b/.", "/a/b", "."},
   553  	{"/a/b", "/a/b/.", "."},
   554  	{"/ab/cd", "/ab/cde", "../cde"},
   555  	{"/ab/cd", "/ab/c", "../c"},
   556  	{"/a/b", "/a/b/c/d", "c/d"},
   557  	{"/a/b", "/a/b/../c", "../c"},
   558  	{"/a/b/../c", "/a/b", "../b"},
   559  	{"/a/b/c", "/a/c/d", "../../c/d"},
   560  	{"/a/b", "/c/d", "../../c/d"},
   561  	{"/a/b/c/d", "/a/b", "../.."},
   562  	{"/a/b/c/d", "/a/b/", "../.."},
   563  	{"/a/b/c/d/", "/a/b", "../.."},
   564  	{"/a/b/c/d/", "/a/b/", "../.."},
   565  	{"/../../a/b", "/../../a/b/c/d", "c/d"},
   566  	{".", "a/b", "a/b"},
   567  	{".", "..", ".."},
   568  
   569  	// can't do purely lexically
   570  	{"..", ".", "err"},
   571  	{"..", "a", "err"},
   572  	{"../..", "..", "err"},
   573  	{"a", "/a", "err"},
   574  	{"/a", "a", "err"},
   575  }
   576  
   577  var winreltests = []RelTests{
   578  	{`C:a\b\c`, `C:a/b/d`, `..\d`},
   579  	{`C:\`, `D:\`, `err`},
   580  	{`C:`, `D:`, `err`},
   581  	{`C:\Projects`, `c:\projects\src`, `src`},
   582  	{`C:\Projects`, `c:\projects`, `.`},
   583  	{`C:\Projects\a\..`, `c:\projects`, `.`},
   584  }
   585  
   586  func TestRel(t *testing.T) {
   587  	for _, os := range []OS{Unix, Windows} {
   588  		tests := append([]RelTests{}, reltests...)
   589  		if os == Windows {
   590  			for i := range tests {
   591  				tests[i].want = FromSlash(tests[i].want, Windows)
   592  			}
   593  			tests = append(tests, winreltests...)
   594  		}
   595  		for _, test := range tests {
   596  			got, err := Rel(test.root, test.path, os)
   597  			if test.want == "err" {
   598  				if err == nil {
   599  					t.Errorf("Rel(%q, %q, %q)=%q, want error", test.root, test.path, os, got)
   600  				}
   601  				continue
   602  			}
   603  			if err != nil {
   604  				t.Errorf("Rel(%q, %q, %q): want %q, got error: %s", test.root, test.path, os, test.want, err)
   605  			}
   606  			if got != test.want {
   607  				t.Errorf("Rel(%q, %q, %q)=%q, want %q", test.root, test.path, os, got, test.want)
   608  			}
   609  		}
   610  	}
   611  }
   612  
   613  type VolumeNameTest struct {
   614  	path string
   615  	vol  string
   616  }
   617  
   618  var volumenametests = []VolumeNameTest{
   619  	{`c:/foo/bar`, `c:`},
   620  	{`c:`, `c:`},
   621  	{`2:`, ``},
   622  	{``, ``},
   623  	{`\\\host`, ``},
   624  	{`\\\host\`, ``},
   625  	{`\\\host\share`, ``},
   626  	{`\\\host\\share`, ``},
   627  	{`\\host`, ``},
   628  	{`//host`, ``},
   629  	{`\\host\`, ``},
   630  	{`//host/`, ``},
   631  	{`\\host\share`, `\\host\share`},
   632  	{`//host/share`, `//host/share`},
   633  	{`\\host\share\`, `\\host\share`},
   634  	{`//host/share/`, `//host/share`},
   635  	{`\\host\share\foo`, `\\host\share`},
   636  	{`//host/share/foo`, `//host/share`},
   637  	{`\\host\share\\foo\\\bar\\\\baz`, `\\host\share`},
   638  	{`//host/share//foo///bar////baz`, `//host/share`},
   639  	{`\\host\share\foo\..\bar`, `\\host\share`},
   640  	{`//host/share/foo/../bar`, `//host/share`},
   641  }
   642  
   643  func TestVolumeName(t *testing.T) {
   644  	for _, os := range []OS{Unix, Windows} {
   645  		if os != Windows {
   646  			return
   647  		}
   648  		for _, v := range volumenametests {
   649  			if vol := VolumeName(v.path, os); vol != v.vol {
   650  				t.Errorf("VolumeName(%q, %q)=%q, want %q", v.path, os, vol, v.vol)
   651  			}
   652  		}
   653  	}
   654  }