src/math/rand/v2/race_test.go

   1 // Copyright 2016 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package rand_test
   6
   7 import (
   8         . "math/rand/v2"
   9         "sync"
  10         "testing"
  11 )
  12
  13 // TestConcurrent exercises the rand API concurrently, triggering situations
  14 // where the race detector is likely to detect issues.
  15 func TestConcurrent(t *testing.T) {
  16         const (
  17                 numRoutines = 10
  18                 numCycles   = 10
  19         )
  20         var wg sync.WaitGroup
  21         defer wg.Wait()
  22         wg.Add(numRoutines)
  23         for i := 0; i < numRoutines; i++ {
  24                 go func(i int) {
  25                         defer wg.Done()
  26                         buf := make([]byte, 997)
  27                         for j := 0; j < numCycles; j++ {
  28                                 var seed int64
  29                                 seed += int64(ExpFloat64())
  30                                 seed += int64(Float32())
  31                                 seed += int64(Float64())
  32                                 seed += int64(IntN(Int()))
  33                                 seed += int64(Int32N(Int32()))
  34                                 seed += int64(Int64N(Int64()))
  35                                 seed += int64(NormFloat64())
  36                                 seed += int64(Uint32())
  37                                 seed += int64(Uint64())
  38                                 for _, p := range Perm(10) {
  39                                         seed += int64(p)
  40                                 }
  41                                 Read(buf)
  42                                 for _, b := range buf {
  43                                         seed += int64(b)
  44                                 }
  45                                 Seed(int64(i*j) * seed)
  46                         }
  47                 }(i)
  48         }
  49 }