1 // Copyright (c) 2023 Uber Technologies, Inc. 2 // 3 // Permission is hereby granted, free of charge, to any person obtaining a copy 4 // of this software and associated documentation files (the "Software"), to deal 5 // in the Software without restriction, including without limitation the rights 6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 // copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in 11 // all copies or substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 // THE SOFTWARE. 20 21 package pool_test 22 23 import ( 24 "runtime/debug" 25 "sync" 26 "testing" 27 28 "github.com/stretchr/testify/require" 29 "go.uber.org/zap/internal/pool" 30 ) 31 32 type pooledValue[T any] struct { 33 value T 34 } 35 36 func TestNew(t *testing.T) { 37 // Disable GC to avoid the victim cache during the test. 38 defer debug.SetGCPercent(debug.SetGCPercent(-1)) 39 40 p := pool.New(func() *pooledValue[string] { 41 return &pooledValue[string]{ 42 value: "new", 43 } 44 }) 45 46 // Probabilistically, 75% of sync.Pool.Put calls will succeed when -race 47 // is enabled (see ref below); attempt to make this quasi-deterministic by 48 // brute force (i.e., put significantly more objects in the pool than we 49 // will need for the test) in order to avoid testing without race enabled. 50 // 51 // ref: https://cs.opensource.google/go/go/+/refs/tags/go1.20.2:src/sync/pool.go;l=100-103 52 for i := 0; i < 1_000; i++ { 53 p.Put(&pooledValue[string]{ 54 value: t.Name(), 55 }) 56 } 57 58 // Ensure that we always get the expected value. Note that this must only 59 // run a fraction of the number of times that Put is called above. 60 for i := 0; i < 10; i++ { 61 func() { 62 x := p.Get() 63 defer p.Put(x) 64 require.Equal(t, t.Name(), x.value) 65 }() 66 } 67 68 // Depool all objects that might be in the pool to ensure that it's empty. 69 for i := 0; i < 1_000; i++ { 70 p.Get() 71 } 72 73 // Now that the pool is empty, it should use the value specified in the 74 // underlying sync.Pool.New func. 75 require.Equal(t, "new", p.Get().value) 76 } 77 78 func TestNew_Race(t *testing.T) { 79 p := pool.New(func() *pooledValue[int] { 80 return &pooledValue[int]{ 81 value: -1, 82 } 83 }) 84 85 var wg sync.WaitGroup 86 defer wg.Wait() 87 88 // Run a number of goroutines that read and write pool object fields to 89 // tease out races. 90 for i := 0; i < 1_000; i++ { 91 i := i 92 93 wg.Add(1) 94 go func() { 95 defer wg.Done() 96 97 x := p.Get() 98 defer p.Put(x) 99 100 // Must both read and write the field. 101 if n := x.value; n >= -1 { 102 x.value = i 103 } 104 }() 105 } 106 } 107