github.com/kaydxh/golang@v0.0.131/go/math/rand/rand_test.go (about) 1 /* 2 *Copyright (c) 2022, kaydxh 3 * 4 *Permission is hereby granted, free of charge, to any person obtaining a copy 5 *of this software and associated documentation files (the "Software"), to deal 6 *in the Software without restriction, including without limitation the rights 7 *to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 8 *copies of the Software, and to permit persons to whom the Software is 9 *furnished to do so, subject to the following conditions: 10 * 11 *The above copyright notice and this permission notice shall be included in all 12 *copies or substantial portions of the Software. 13 * 14 *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 *IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 *FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 17 *AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 18 *LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 19 *OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 20 *SOFTWARE. 21 */ 22 package rand_test 23 24 import ( 25 "fmt" 26 "math/rand" 27 "strings" 28 "testing" 29 "time" 30 31 rand_ "github.com/kaydxh/golang/go/math/rand" 32 33 "github.com/stretchr/testify/assert" 34 ) 35 36 func TestRand(t *testing.T) { 37 s := fmt.Sprintf("%08v", rand.New(rand.NewSource(time.Now().UnixNano())).Int31n(100000000)) 38 fmt.Printf("s: %v\n", s) 39 40 ss := "abc_dvg_123" 41 fmt.Printf("ss %v\n", ss) 42 ts := strings.TrimPrefix(ss, "abc_dvg") 43 fmt.Printf("ts: %v\n", ts) 44 45 ns := "_abc" 46 nns := strings.Split(ns, "_") 47 fmt.Printf("nns: %v\n", nns) 48 49 } 50 51 func TestRangeInt(t *testing.T) { 52 testCases := []struct { 53 min int 54 max int 55 }{ 56 { 57 min: 10, 58 max: 12, 59 }, 60 { 61 min: 10000000, 62 max: 100000000, 63 }, 64 } 65 66 for i, testCase := range testCases { 67 t.Run(fmt.Sprintf("test-%v", i), func(t *testing.T) { 68 r, err := rand_.RangeInt(testCase.min, testCase.max) 69 if err != nil { 70 t.Fatalf("failed to rand int, err: %v", err) 71 } 72 t.Logf("random: %v", r) 73 74 assert.GreaterOrEqual(t, r, testCase.min) 75 assert.LessOrEqual(t, r, testCase.max) 76 77 }) 78 } 79 } 80 81 func TestRead(t *testing.T) { 82 testCases := []struct { 83 p []byte 84 }{ 85 { 86 p: make([]byte, 10), 87 }, 88 { 89 p: make([]byte, 20), 90 }, 91 } 92 93 for i, testCase := range testCases { 94 t.Run(fmt.Sprintf("test-%v", i), func(t *testing.T) { 95 n, err := rand_.Read(testCase.p) 96 if err != nil { 97 t.Fatalf("failed to rand int, err: %v", err) 98 } 99 t.Logf("read n: %v, p: %v", n, testCase.p) 100 101 assert.Equal(t, len(testCase.p), n) 102 103 }) 104 } 105 } 106 107 func TestRangeString(t *testing.T) { 108 testCases := []struct { 109 n int 110 }{ 111 { 112 n: 0, 113 }, 114 { 115 n: 5, 116 }, 117 { 118 n: 8, 119 }, 120 } 121 122 for i, testCase := range testCases { 123 t.Run(fmt.Sprintf("test-%v", i), func(t *testing.T) { 124 str := rand_.RangeString(testCase.n) 125 t.Logf("str: %v", str) 126 assert.Equal(t, len(str), testCase.n) 127 128 }) 129 } 130 131 }