go-ethereum/common/prque/lazyqueue_test.go
Martin Holst Swende 4d3525610e
all: remove deprecated uses of math.rand (#26710)
This PR is a (superior) alternative to https://github.com/ethereum/go-ethereum/pull/26708, it handles deprecation, primarily two specific cases. 

`rand.Seed` is typically used in two ways
- `rand.Seed(time.Now().UnixNano())` -- we seed it, just to be sure to get some random, and not always get the same thing on every run. This is not needed, with global seeding, so those are just removed. 
- `rand.Seed(1)` this is typically done to ensure we have a stable test. If we rely on this, we need to fix up the tests to use a deterministic prng-source. A few occurrences like this has been replaced with a proper custom source. 

`rand.Read` has been replaced by `crypto/rand`.`Read` in this PR.
2023-02-16 14:36:58 -05:00

124 lines
2.8 KiB
Go

// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package prque
import (
"math/rand"
"sync"
"testing"
"time"
"github.com/ethereum/go-ethereum/common/mclock"
)
const (
testItems = 1000
testPriorityStep = 100
testSteps = 1000000
testStepPeriod = time.Millisecond
testQueueRefresh = time.Second
testAvgRate = float64(testPriorityStep) / float64(testItems) / float64(testStepPeriod)
)
type lazyItem struct {
p, maxp int64
last mclock.AbsTime
index int
}
func testPriority(a interface{}) int64 {
return a.(*lazyItem).p
}
func testMaxPriority(a interface{}, until mclock.AbsTime) int64 {
i := a.(*lazyItem)
dt := until - i.last
i.maxp = i.p + int64(float64(dt)*testAvgRate)
return i.maxp
}
func testSetIndex(a interface{}, i int) {
a.(*lazyItem).index = i
}
func TestLazyQueue(t *testing.T) {
clock := &mclock.Simulated{}
q := NewLazyQueue(testSetIndex, testPriority, testMaxPriority, clock, testQueueRefresh)
var (
items [testItems]lazyItem
maxPri int64
)
for i := range items[:] {
items[i].p = rand.Int63n(testPriorityStep * 10)
if items[i].p > maxPri {
maxPri = items[i].p
}
items[i].index = -1
q.Push(&items[i])
}
var (
lock sync.Mutex
wg sync.WaitGroup
stopCh = make(chan chan struct{})
)
defer wg.Wait()
wg.Add(1)
go func() {
defer wg.Done()
for {
select {
case <-clock.After(testQueueRefresh):
lock.Lock()
q.Refresh()
lock.Unlock()
case <-stopCh:
return
}
}
}()
for c := 0; c < testSteps; c++ {
i := rand.Intn(testItems)
lock.Lock()
items[i].p += rand.Int63n(testPriorityStep*2-1) + 1
if items[i].p > maxPri {
maxPri = items[i].p
}
items[i].last = clock.Now()
if items[i].p > items[i].maxp {
q.Update(items[i].index)
}
if rand.Intn(100) == 0 {
p := q.PopItem().(*lazyItem)
if p.p != maxPri {
lock.Unlock()
close(stopCh)
t.Fatalf("incorrect item (best known priority %d, popped %d)", maxPri, p.p)
}
q.Push(p)
}
lock.Unlock()
clock.Run(testStepPeriod)
clock.WaitForTimers(1)
}
close(stopCh)
}