ioutil_test.go

Documentation: io/ioutil

		 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_test
		 6  
		 7  import (
		 8  	"bytes"
		 9  	. "io/ioutil"
		10  	"os"
		11  	"path/filepath"
		12  	"testing"
		13  )
		14  
		15  func checkSize(t *testing.T, path string, size int64) {
		16  	dir, err := os.Stat(path)
		17  	if err != nil {
		18  		t.Fatalf("Stat %q (looking for size %d): %s", path, size, err)
		19  	}
		20  	if dir.Size() != size {
		21  		t.Errorf("Stat %q: size %d want %d", path, dir.Size(), size)
		22  	}
		23  }
		24  
		25  func TestReadFile(t *testing.T) {
		26  	filename := "rumpelstilzchen"
		27  	contents, err := ReadFile(filename)
		28  	if err == nil {
		29  		t.Fatalf("ReadFile %s: error expected, none found", filename)
		30  	}
		31  
		32  	filename = "ioutil_test.go"
		33  	contents, err = ReadFile(filename)
		34  	if err != nil {
		35  		t.Fatalf("ReadFile %s: %v", filename, err)
		36  	}
		37  
		38  	checkSize(t, filename, int64(len(contents)))
		39  }
		40  
		41  func TestWriteFile(t *testing.T) {
		42  	f, err := TempFile("", "ioutil-test")
		43  	if err != nil {
		44  		t.Fatal(err)
		45  	}
		46  	filename := f.Name()
		47  	data := "Programming today is a race between software engineers striving to " +
		48  		"build bigger and better idiot-proof programs, and the Universe trying " +
		49  		"to produce bigger and better idiots. So far, the Universe is winning."
		50  
		51  	if err := WriteFile(filename, []byte(data), 0644); err != nil {
		52  		t.Fatalf("WriteFile %s: %v", filename, err)
		53  	}
		54  
		55  	contents, err := ReadFile(filename)
		56  	if err != nil {
		57  		t.Fatalf("ReadFile %s: %v", filename, err)
		58  	}
		59  
		60  	if string(contents) != data {
		61  		t.Fatalf("contents = %q\nexpected = %q", string(contents), data)
		62  	}
		63  
		64  	// cleanup
		65  	f.Close()
		66  	os.Remove(filename) // ignore error
		67  }
		68  
		69  func TestReadOnlyWriteFile(t *testing.T) {
		70  	if os.Getuid() == 0 {
		71  		t.Skipf("Root can write to read-only files anyway, so skip the read-only test.")
		72  	}
		73  
		74  	// We don't want to use TempFile directly, since that opens a file for us as 0600.
		75  	tempDir, err := TempDir("", t.Name())
		76  	if err != nil {
		77  		t.Fatalf("TempDir %s: %v", t.Name(), err)
		78  	}
		79  	defer os.RemoveAll(tempDir)
		80  	filename := filepath.Join(tempDir, "blurp.txt")
		81  
		82  	shmorp := []byte("shmorp")
		83  	florp := []byte("florp")
		84  	err = WriteFile(filename, shmorp, 0444)
		85  	if err != nil {
		86  		t.Fatalf("WriteFile %s: %v", filename, err)
		87  	}
		88  	err = WriteFile(filename, florp, 0444)
		89  	if err == nil {
		90  		t.Fatalf("Expected an error when writing to read-only file %s", filename)
		91  	}
		92  	got, err := ReadFile(filename)
		93  	if err != nil {
		94  		t.Fatalf("ReadFile %s: %v", filename, err)
		95  	}
		96  	if !bytes.Equal(got, shmorp) {
		97  		t.Fatalf("want %s, got %s", shmorp, got)
		98  	}
		99  }
	 100  
	 101  func TestReadDir(t *testing.T) {
	 102  	dirname := "rumpelstilzchen"
	 103  	_, err := ReadDir(dirname)
	 104  	if err == nil {
	 105  		t.Fatalf("ReadDir %s: error expected, none found", dirname)
	 106  	}
	 107  
	 108  	dirname = ".."
	 109  	list, err := ReadDir(dirname)
	 110  	if err != nil {
	 111  		t.Fatalf("ReadDir %s: %v", dirname, err)
	 112  	}
	 113  
	 114  	foundFile := false
	 115  	foundSubDir := false
	 116  	for _, dir := range list {
	 117  		switch {
	 118  		case !dir.IsDir() && dir.Name() == "io_test.go":
	 119  			foundFile = true
	 120  		case dir.IsDir() && dir.Name() == "ioutil":
	 121  			foundSubDir = true
	 122  		}
	 123  	}
	 124  	if !foundFile {
	 125  		t.Fatalf("ReadDir %s: io_test.go file not found", dirname)
	 126  	}
	 127  	if !foundSubDir {
	 128  		t.Fatalf("ReadDir %s: ioutil directory not found", dirname)
	 129  	}
	 130  }
	 131
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