github.com/lingyao2333/mo-zero@v1.4.1/zrpc/resolver/internal/subset_test.go (about)

     1  package internal
     2  
     3  import (
     4  	"strconv"
     5  	"testing"
     6  
     7  	"github.com/lingyao2333/mo-zero/core/mathx"
     8  	"github.com/stretchr/testify/assert"
     9  )
    10  
    11  func TestSubset(t *testing.T) {
    12  	tests := []struct {
    13  		name string
    14  		set  int
    15  		sub  int
    16  	}{
    17  		{
    18  			name: "more vals to subset",
    19  			set:  100,
    20  			sub:  36,
    21  		},
    22  		{
    23  			name: "less vals to subset",
    24  			set:  100,
    25  			sub:  200,
    26  		},
    27  	}
    28  
    29  	for _, test := range tests {
    30  		test := test
    31  		t.Run(test.name, func(t *testing.T) {
    32  			var vals []string
    33  			for i := 0; i < test.set; i++ {
    34  				vals = append(vals, strconv.Itoa(i))
    35  			}
    36  
    37  			m := make(map[interface{}]int)
    38  			for i := 0; i < 1000; i++ {
    39  				set := subset(append([]string(nil), vals...), test.sub)
    40  				if test.sub < test.set {
    41  					assert.Equal(t, test.sub, len(set))
    42  				} else {
    43  					assert.Equal(t, test.set, len(set))
    44  				}
    45  
    46  				for _, val := range set {
    47  					m[val]++
    48  				}
    49  			}
    50  
    51  			assert.True(t, mathx.CalcEntropy(m) > 0.95)
    52  		})
    53  	}
    54  }