1package store

2

3import (

4 "io"

5 "os"

6 "testing"

7)

8

9func TestMsgreader(t *testing.T) {

10 _, err := io.Copy(io.Discard, &MsgReader{prefix: []byte("hello"), path: "bogus.txt", size: int64(len("hello"))})

11 if err == nil || !os.IsNotExist(err) {

12 t.Fatalf("expected error for non-existing file, got %s", err)

13 }

14

15 if err := os.WriteFile("emptyfile_test.txt", []byte{}, 0660); err != nil {

16 t.Fatalf("writing emptyfile_test.txt: %s", err)

17 }

18 defer os.Remove("emptyfile_test.txt")

19 mr := &MsgReader{prefix: []byte("hello"), path: "emptyfile_test.txt", size: int64(len("hello"))}

20 defer mr.Close()

21 if buf, err := io.ReadAll(mr); err != nil {

22 t.Fatalf("readall: %s", err)

23 } else if string(buf) != "hello" {

24 t.Fatalf("got %q, expected %q", buf, "hello")

25 }

26

27 if err := os.WriteFile("msgreader_test.txt", []byte(" world"), 0660); err != nil {

28 t.Fatalf("writing msgreader_test.txt: %s", err)

29 }

30 defer os.Remove("msgreader_test.txt")

31 mr = &MsgReader{prefix: []byte("hello"), path: "msgreader_test.txt", size: int64(len("hello world"))}

32 defer mr.Close()

33 if buf, err := io.ReadAll(mr); err != nil {

34 t.Fatalf("readall: %s", err)

35 } else if string(buf) != "hello world" {

36 t.Fatalf("got %q, expected %q", buf, "hello world")

37 }

38

39 mr.Reset()

40 buf := make([]byte, 32)

41 if n, err := mr.ReadAt(buf, 1); err != nil && err != io.EOF {

42 t.Fatalf("readat: n %d, s %q, err %s", n, buf[:n], err)

43 } else if n != len("ello world") || string(buf[:n]) != "ello world" {

44 t.Fatalf("readat: got %d bytes (%q), expected %d (%q)", n, buf, int64(len("ello world")), "ello world")

45 }

46

47 // Read with 1 byte at a time to exercise the offset/buffer-length calculations.

48 buf = make([]byte, 1)

49 var result []byte

50 mr = &MsgReader{prefix: []byte("hello"), path: "msgreader_test.txt", size: int64(len("hello world"))}

51 for {

52 n, err := mr.Read(buf)

53 if n > 0 {

54 result = append(result, buf...)

55 }

56 if err == io.EOF {

57 break

58 }

59 if err != nil {

60 t.Fatalf("read: %s", err)

61 }

62 }

63 if string(result) != "hello world" {

64 t.Fatalf("got %q, want %q", result, "hello world")

65 }

66

67 if err := mr.Close(); err != nil {

68 t.Fatalf("close: %v", err)

69 }

70

71 f, err := os.Open("msgreader_test.txt")

72 if err != nil {

73 t.Fatalf("open: %v", err)

74 }

75 mr = FileMsgReader([]byte("hello"), f)

76

77 if mr.Size() != int64(len("hello world")) {

78 t.Fatalf("size, got %d, expect %d", mr.Size(), len("hello world"))

79 }

80

81 if err := mr.Close(); err != nil {

82 t.Fatalf("close: %v", err)

83 }

84}

85