github.com/tinygo-org/tinygo@v0.31.3-0.20240404173401-90b0bf646c27/src/os/read_test.go (about)

     1  //go:build !baremetal && !js && !wasip1
     2  
     3  // Copyright 2009 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  package os_test
     8  
     9  import (
    10  	"bytes"
    11  	. "os"
    12  	"path/filepath"
    13  	"testing"
    14  )
    15  
    16  func checkNamedSize(t *testing.T, path string, size int64) {
    17  	// TODO: this statement fails on wasi, possibly it objects to reading Stat on a symlink
    18  	dir, err := Stat(path)
    19  	if err != nil {
    20  		t.Fatalf("Stat %q (looking for size %d): %s", path, size, err)
    21  		return
    22  	}
    23  	if dir.Size() != size {
    24  		t.Errorf("Stat %q: size %d want %d", path, dir.Size(), size)
    25  	}
    26  }
    27  
    28  func TestReadFile(t *testing.T) {
    29  	filename := "rumpelstilzchen"
    30  	contents, err := ReadFile(filename)
    31  	if err == nil {
    32  		t.Fatalf("ReadFile %s: error expected, none found", filename)
    33  	}
    34  
    35  	filename = "read_test.go"
    36  	contents, err = ReadFile(filename)
    37  	if err != nil {
    38  		t.Fatalf("ReadFile %s: %v", filename, err)
    39  	}
    40  
    41  	checkNamedSize(t, filename, int64(len(contents)))
    42  }
    43  
    44  func TestWriteFile(t *testing.T) {
    45  	f, err := CreateTemp("", "ioutil-test")
    46  	if err != nil {
    47  		t.Fatal(err)
    48  	}
    49  	defer f.Close()
    50  	defer Remove(f.Name())
    51  
    52  	msg := "Programming today is a race between software engineers striving to " +
    53  		"build bigger and better idiot-proof programs, and the Universe trying " +
    54  		"to produce bigger and better idiots. So far, the Universe is winning."
    55  
    56  	if err := WriteFile(f.Name(), []byte(msg), 0644); err != nil {
    57  		t.Fatalf("WriteFile %s: %v", f.Name(), err)
    58  	}
    59  
    60  	data, err := ReadFile(f.Name())
    61  	if err != nil {
    62  		t.Fatalf("ReadFile %s: %v", f.Name(), err)
    63  	}
    64  
    65  	if string(data) != msg {
    66  		t.Fatalf("ReadFile: wrong data:\nhave %q\nwant %q", string(data), msg)
    67  	}
    68  }
    69  
    70  func TestReadOnlyWriteFile(t *testing.T) {
    71  	// TODO: also skip on wasi, where file permissions are ignored
    72  	if Getuid() == 0 {
    73  		t.Skipf("Root can write to read-only files anyway, so skip the read-only test.")
    74  	}
    75  
    76  	// We don't want to use CreateTemp directly, since that opens a file for us as 0600.
    77  	tempDir, err := MkdirTemp("", t.Name())
    78  	if err != nil {
    79  		t.Fatal(err)
    80  	}
    81  	defer RemoveAll(tempDir)
    82  	filename := filepath.Join(tempDir, "blurp.txt")
    83  
    84  	shmorp := []byte("shmorp")
    85  	florp := []byte("florp")
    86  	err = WriteFile(filename, shmorp, 0444)
    87  	if err != nil {
    88  		t.Fatalf("WriteFile %s: %v", filename, err)
    89  	}
    90  	err = WriteFile(filename, florp, 0444)
    91  	if err == nil {
    92  		t.Fatalf("Expected an error when writing to read-only file %s", filename)
    93  	}
    94  	got, err := ReadFile(filename)
    95  	if err != nil {
    96  		t.Fatalf("ReadFile %s: %v", filename, err)
    97  	}
    98  	if !bytes.Equal(got, shmorp) {
    99  		t.Fatalf("want %s, got %s", shmorp, got)
   100  	}
   101  }