github.com/vescale/zgraph@v0.0.0-20230410094002-959c02d50f95/internal/mathutil/math_test.go (about)

     1  // Copyright 2019 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package mathutil
    16  
    17  import (
    18  	"math/rand"
    19  	"strconv"
    20  	"testing"
    21  
    22  	"github.com/stretchr/testify/require"
    23  )
    24  
    25  func TestStrLenOfUint64Fast(t *testing.T) {
    26  	t.Run("RandomInput", func(t *testing.T) {
    27  		for i := 0; i < 1000000; i++ {
    28  			num := rand.Uint64()
    29  			expected := len(strconv.FormatUint(num, 10))
    30  			actual := StrLenOfUint64Fast(num)
    31  			require.Equal(t, expected, actual)
    32  		}
    33  	})
    34  
    35  	t.Run("ManualInput", func(t *testing.T) {
    36  		nums := [22]uint64{0,
    37  			1, 12, 123, 1234, 12345,
    38  			123456, 1234567, 12345678, 123456789, 1234567890,
    39  			1234567891, 12345678912, 123456789123, 1234567891234, 12345678912345,
    40  			123456789123456, 1234567891234567, 12345678912345678, 123456789123456789,
    41  			123456789123457890,
    42  			^uint64(0),
    43  		}
    44  		for _, num := range nums {
    45  			expected := len(strconv.FormatUint(num, 10))
    46  			actual := StrLenOfUint64Fast(num)
    47  			require.Equal(t, expected, actual)
    48  		}
    49  	})
    50  }
    51  
    52  func TestMaxMin(t *testing.T) {
    53  	require.Equal(t, 1, Min(1, 2))
    54  	require.Equal(t, 1, Min(2, 1))
    55  	require.Equal(t, 1, Min(4, 2, 1, 3))
    56  	require.Equal(t, 1, Min(1, 1))
    57  
    58  	require.Equal(t, 2, Max(1, 2))
    59  	require.Equal(t, 2, Max(2, 1))
    60  	require.Equal(t, 4, Max(4, 2, 1, 3))
    61  	require.Equal(t, 1, Max(1, 1))
    62  
    63  	require.Equal(t, int64(1), Min(int64(1), int64(2)))
    64  	require.Equal(t, int64(2), Max(int64(2), int64(1)))
    65  	require.Equal(t, int64(1), Min(int64(4), int64(2), int64(1), int64(3)))
    66  	require.Equal(t, int64(1), Max(int64(1), int64(1)))
    67  	require.Equal(t, 1.0, Min(4.0, 2.0, 1.0, 3.0))
    68  	require.Equal(t, 4.0, Max(4.0, 2.0, 1.0, 3.0))
    69  
    70  	require.Equal(t, "ab", Min("ab", "xy"))
    71  	require.Equal(t, "xy", Max("ab", "xy"))
    72  	require.Equal(t, "ab", Max("ab", "ab"))
    73  }
    74  
    75  func TestClamp(t *testing.T) {
    76  	require.Equal(t, 3, Clamp(100, 1, 3))
    77  	require.Equal(t, 2.0, Clamp(float64(2), 1.0, 3.0))
    78  	require.Equal(t, float32(1.0), Clamp(float32(0), 1.0, 3.0))
    79  	require.Equal(t, 1, Clamp(0, 1, 1))
    80  	require.Equal(t, 1, Clamp(100, 1, 1))
    81  	require.Equal(t, "ab", Clamp("aa", "ab", "xy"))
    82  	require.Equal(t, "xy", Clamp("yy", "ab", "xy"))
    83  	require.Equal(t, "ab", Clamp("ab", "ab", "ab"))
    84  }