byteio - varint_test.go

     1  package byteio
     2  
     3  import (
     4  	"bytes"
     5  	"testing"
     6  )
     7  
     8  func TestLittleEndianVarUint(t *testing.T) {
     9  	buf := bytes.NewBuffer(make([]byte, 0, 9))
    10  	for n, test := range [...]struct {
    11  		Input  uint64
    12  		Output []byte
    13  	}{
    14  		{0, []byte{0}},
    15  		{1, []byte{1}},
    16  		{127, []byte{127}},
    17  		{128, []byte{128, 0}},
    18  		{129, []byte{129, 0}},
    19  		{255, []byte{255, 0}},
    20  		{256, []byte{128, 1}},
    21  		{257, []byte{129, 1}},
    22  		{300, []byte{172, 1}},
    23  		{512, []byte{128, 3}},
    24  		{1024, []byte{128, 7}},
    25  		{2048, []byte{128, 15}},
    26  		{4096, []byte{128, 31}},
    27  		{8192, []byte{128, 63}},
    28  		{16384, []byte{128, 127}},
    29  		{16511, []byte{255, 127}},
    30  		{16512, []byte{128, 128, 0}},
    31  		{32768, []byte{128, 255, 0}},
    32  		{65536, []byte{128, 255, 2}},
    33  		{131072, []byte{128, 255, 6}},
    34  		{262144, []byte{128, 255, 14}},
    35  		{524288, []byte{128, 255, 30}},
    36  		{1048576, []byte{128, 255, 62}},
    37  		{2097152, []byte{128, 255, 126}},
    38  		{134217728, []byte{128, 255, 254, 62}},
    39  		{268435456, []byte{128, 255, 254, 126}},
    40  		{17179869184, []byte{128, 255, 254, 254, 62}},
    41  		{18446744073709551615, []byte{255, 254, 254, 254, 254, 254, 254, 254, 254}},
    42  	} {
    43  		buf.Reset()
    44  		(&LittleEndianWriter{Writer: buf}).WriteUintX(test.Input)
    45  		if !bytes.Equal(buf.Bytes(), test.Output) {
    46  			t.Errorf("test %d.1: expecting %v, got %v", n+1, test.Output, buf)
    47  			buf.Reset()
    48  			buf.Write(test.Output)
    49  		}
    50  		num, _, _ := (&LittleEndianReader{Reader: buf}).ReadUintX()
    51  		if num != test.Input {
    52  			t.Errorf("test %d.2: expecting %d, got %d", n+1, test.Input, num)
    53  		}
    54  	}
    55  }
    56  
    57  func FuzzLittleEndianVarInt(f *testing.F) {
    58  	for _, seed := range []uint64{0, 127, 128, 255, 256, 1024, 16512, 134217728, 18446744073709551615} {
    59  		f.Add(seed)
    60  	}
    61  
    62  	f.Fuzz(func(t *testing.T, in uint64) {
    63  		var buf bytes.Buffer
    64  		(&LittleEndianWriter{Writer: &buf}).WriteUintX(in)
    65  		num, _, _ := (&LittleEndianReader{Reader: &buf}).ReadUintX()
    66  
    67  		if num != in {
    68  			t.Errorf("failed on %d", in)
    69  		}
    70  	})
    71  }
    72  
    73  func TestBigEndianVarUint(t *testing.T) {
    74  	buf := bytes.NewBuffer(make([]byte, 0, 9))
    75  	for n, test := range [...]struct {
    76  		Input  uint64
    77  		Output []byte
    78  	}{
    79  		{0, []byte{0}},
    80  		{1, []byte{1}},
    81  		{127, []byte{127}},
    82  		{128, []byte{128, 0}},
    83  		{129, []byte{128, 1}},
    84  		{130, []byte{128, 2}},
    85  		{255, []byte{128, 127}},
    86  		{256, []byte{129, 0}},
    87  		{257, []byte{129, 1}},
    88  		{512, []byte{131, 0}},
    89  		{1024, []byte{135, 0}},
    90  		{2048, []byte{143, 0}},
    91  		{4096, []byte{159, 0}},
    92  		{8192, []byte{191, 0}},
    93  		{16384, []byte{255, 0}},
    94  		{16385, []byte{255, 1}},
    95  		{16511, []byte{255, 127}},
    96  		{16512, []byte{128, 128, 0}},
    97  		{32768, []byte{128, 255, 0}},
    98  		{65536, []byte{130, 255, 0}},
    99  		{131072, []byte{134, 255, 0}},
   100  		{262144, []byte{142, 255, 0}},
   101  		{2113663, []byte{255, 255, 127}},
   102  		{2113664, []byte{128, 128, 128, 0}},
   103  		{18446744073709551615, []byte{254, 254, 254, 254, 254, 254, 254, 254, 255}},
   104  		{9295997013522923646, []byte{255, 255, 255, 255, 255, 255, 255, 255, 126}},
   105  		{9295997013522923647, []byte{255, 255, 255, 255, 255, 255, 255, 255, 127}},
   106  		{9295997013522923648, []byte{191, 191, 191, 191, 191, 191, 191, 191, 128}},
   107  		{9295997013522923649, []byte{191, 191, 191, 191, 191, 191, 191, 191, 129}},
   108  	} {
   109  		buf.Reset()
   110  		(&BigEndianWriter{Writer: buf}).WriteUintX(test.Input)
   111  		if !bytes.Equal(buf.Bytes(), test.Output) {
   112  			t.Errorf("test %d.1: expecting %v, got %v", n+1, test.Output, buf)
   113  			buf.Reset()
   114  			buf.Write(test.Output)
   115  		}
   116  		num, _, _ := (&BigEndianReader{Reader: buf}).ReadUintX()
   117  		if num != test.Input {
   118  			t.Errorf("test %d.2: expecting %d, got %d", n+1, test.Input, num)
   119  		}
   120  	}
   121  }
   122  
   123  func FuzzBigEndianVarInt(f *testing.F) {
   124  	for _, seed := range []uint64{0, 127, 128, 255, 256, 1024, 16512, 134217728, 18446744073709551615} {
   125  		f.Add(seed)
   126  	}
   127  
   128  	f.Fuzz(func(t *testing.T, in uint64) {
   129  		var buf bytes.Buffer
   130  		(&BigEndianWriter{Writer: &buf}).WriteUintX(in)
   131  		num, _, _ := (&BigEndianReader{Reader: &buf}).ReadUintX()
   132  
   133  		if num != in {
   134  			t.Errorf("failed on %d", in)
   135  		}
   136  	})
   137  }
   138