github.com/c12o16h1/go/src@v0.0.0-20200114212001-5a151c0f00ed/io/ioutil/ioutil_test.go (about)

     1  // Copyright 2009 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 ioutil
     6  
     7  import (
     8  	"bytes"
     9  	"os"
    10  	"path/filepath"
    11  	"testing"
    12  )
    13  
    14  func checkSize(t *testing.T, path string, size int64) {
    15  	dir, err := os.Stat(path)
    16  	if err != nil {
    17  		t.Fatalf("Stat %q (looking for size %d): %s", path, size, err)
    18  	}
    19  	if dir.Size() != size {
    20  		t.Errorf("Stat %q: size %d want %d", path, dir.Size(), size)
    21  	}
    22  }
    23  
    24  func TestReadFile(t *testing.T) {
    25  	filename := "rumpelstilzchen"
    26  	contents, err := ReadFile(filename)
    27  	if err == nil {
    28  		t.Fatalf("ReadFile %s: error expected, none found", filename)
    29  	}
    30  
    31  	filename = "ioutil_test.go"
    32  	contents, err = ReadFile(filename)
    33  	if err != nil {
    34  		t.Fatalf("ReadFile %s: %v", filename, err)
    35  	}
    36  
    37  	checkSize(t, filename, int64(len(contents)))
    38  }
    39  
    40  func TestWriteFile(t *testing.T) {
    41  	f, err := TempFile("", "ioutil-test")
    42  	if err != nil {
    43  		t.Fatal(err)
    44  	}
    45  	filename := f.Name()
    46  	data := "Programming today is a race between software engineers striving to " +
    47  		"build bigger and better idiot-proof programs, and the Universe trying " +
    48  		"to produce bigger and better idiots. So far, the Universe is winning."
    49  
    50  	if err := WriteFile(filename, []byte(data), 0644); err != nil {
    51  		t.Fatalf("WriteFile %s: %v", filename, err)
    52  	}
    53  
    54  	contents, err := ReadFile(filename)
    55  	if err != nil {
    56  		t.Fatalf("ReadFile %s: %v", filename, err)
    57  	}
    58  
    59  	if string(contents) != data {
    60  		t.Fatalf("contents = %q\nexpected = %q", string(contents), data)
    61  	}
    62  
    63  	// cleanup
    64  	f.Close()
    65  	os.Remove(filename) // ignore error
    66  }
    67  
    68  func TestReadOnlyWriteFile(t *testing.T) {
    69  	if os.Getuid() == 0 {
    70  		t.Skipf("Root can write to read-only files anyway, so skip the read-only test.")
    71  	}
    72  
    73  	// We don't want to use TempFile directly, since that opens a file for us as 0600.
    74  	tempDir, err := TempDir("", t.Name())
    75  	if err != nil {
    76  		t.Fatalf("TempDir %s: %v", t.Name(), err)
    77  	}
    78  	defer os.RemoveAll(tempDir)
    79  	filename := filepath.Join(tempDir, "blurp.txt")
    80  
    81  	shmorp := []byte("shmorp")
    82  	florp := []byte("florp")
    83  	err = WriteFile(filename, shmorp, 0444)
    84  	if err != nil {
    85  		t.Fatalf("WriteFile %s: %v", filename, err)
    86  	}
    87  	err = WriteFile(filename, florp, 0444)
    88  	if err == nil {
    89  		t.Fatalf("Expected an error when writing to read-only file %s", filename)
    90  	}
    91  	got, err := ReadFile(filename)
    92  	if err != nil {
    93  		t.Fatalf("ReadFile %s: %v", filename, err)
    94  	}
    95  	if !bytes.Equal(got, shmorp) {
    96  		t.Fatalf("want %s, got %s", shmorp, got)
    97  	}
    98  }
    99  
   100  func TestReadDir(t *testing.T) {
   101  	dirname := "rumpelstilzchen"
   102  	_, err := ReadDir(dirname)
   103  	if err == nil {
   104  		t.Fatalf("ReadDir %s: error expected, none found", dirname)
   105  	}
   106  
   107  	dirname = ".."
   108  	list, err := ReadDir(dirname)
   109  	if err != nil {
   110  		t.Fatalf("ReadDir %s: %v", dirname, err)
   111  	}
   112  
   113  	foundFile := false
   114  	foundSubDir := false
   115  	for _, dir := range list {
   116  		switch {
   117  		case !dir.IsDir() && dir.Name() == "io_test.go":
   118  			foundFile = true
   119  		case dir.IsDir() && dir.Name() == "ioutil":
   120  			foundSubDir = true
   121  		}
   122  	}
   123  	if !foundFile {
   124  		t.Fatalf("ReadDir %s: io_test.go file not found", dirname)
   125  	}
   126  	if !foundSubDir {
   127  		t.Fatalf("ReadDir %s: ioutil directory not found", dirname)
   128  	}
   129  }