github.com/siglens/siglens@v0.0.0-20240328180423-f7ce9ae441ed/pkg/segment/writer/metrics/compress/bit_writer_test.go (about)

     1  /*
     2  Copyright 2023.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package compress
    18  
    19  import (
    20  	"bytes"
    21  	"encoding/binary"
    22  	"testing"
    23  
    24  	fuzz "github.com/google/gofuzz"
    25  	"github.com/stretchr/testify/assert"
    26  	"github.com/stretchr/testify/require"
    27  )
    28  
    29  func Test_bitWriter_writeBit(t *testing.T) {
    30  	tests := []struct {
    31  		name   string
    32  		binary string
    33  		hex    uint8
    34  	}{
    35  		{
    36  			name:   "write 1",
    37  			binary: "00000001",
    38  			hex:    0x1,
    39  		},
    40  		{
    41  			name:   "write 8",
    42  			binary: "00001000",
    43  			hex:    0x8,
    44  		},
    45  		{
    46  			name:   "write 113",
    47  			binary: "01110001",
    48  			hex:    0x71,
    49  		},
    50  		{
    51  			name:   "write 255",
    52  			binary: "11111111",
    53  			hex:    0xff,
    54  		},
    55  	}
    56  	for _, tt := range tests {
    57  		t.Run(tt.name, func(t *testing.T) {
    58  			buf := new(bytes.Buffer)
    59  			bw := newBitWriter(buf)
    60  			for i := 0; i < len(tt.binary); i++ {
    61  				var err error
    62  				if tt.binary[i] == '1' {
    63  					err = bw.writeBit(one)
    64  				} else {
    65  					err = bw.writeBit(zero)
    66  				}
    67  				require.Nil(t, err)
    68  			}
    69  			assert.Equal(t, tt.hex, buf.Bytes()[0])
    70  		})
    71  	}
    72  }
    73  
    74  func Test_bitWriter_writeBits(t *testing.T) {
    75  	f := fuzz.New().NilChance(0)
    76  
    77  	for i := 0; i < 10; i++ {
    78  		var u64 uint64
    79  		f.Fuzz(&u64)
    80  
    81  		buf := new(bytes.Buffer)
    82  		bw := newBitWriter(buf)
    83  		require.Nil(t, bw.writeBits(u64, 64))
    84  
    85  		wantBytes := make([]byte, 8)
    86  		binary.BigEndian.PutUint64(wantBytes, u64)
    87  
    88  		assert.Equal(t, wantBytes, buf.Bytes())
    89  	}
    90  }
    91  
    92  func Test_bitWriter_writeByte(t *testing.T) {
    93  	var b byte = 0x1
    94  	for i := 0; i < 256; i++ {
    95  		buf := new(bytes.Buffer)
    96  		require.Nil(t, buf.WriteByte(b))
    97  		bw := newBitWriter(buf)
    98  		require.Nil(t, bw.writeByte(b))
    99  		assert.Equal(t, b, buf.Bytes()[0])
   100  		b++
   101  	}
   102  }