Files
tendermint/libs/common/random_test.go
ValarDragon 99e582d79a crypto: Refactor to move files out of the top level directory
Currently the top level directory contains basically all of the code
for the crypto package. This PR moves the crypto code into submodules
in a similar manner to what `golang/x/crypto` does. This improves code
organization.

Ref discussion: https://github.com/tendermint/tendermint/pull/1966

Closes #1956
2018-07-18 08:38:44 -07:00

119 lines
2.5 KiB
Go

package common
import (
"bytes"
"encoding/json"
"fmt"
mrand "math/rand"
"sync"
"testing"
"time"
"github.com/stretchr/testify/assert"
)
func TestRandStr(t *testing.T) {
l := 243
s := RandStr(l)
assert.Equal(t, l, len(s))
}
func TestRandBytes(t *testing.T) {
l := 243
b := RandBytes(l)
assert.Equal(t, l, len(b))
}
func TestRandIntn(t *testing.T) {
n := 243
for i := 0; i < 100; i++ {
x := RandIntn(n)
assert.True(t, x < n)
}
}
// Test to make sure that we never call math.rand().
// We do this by ensuring that outputs are deterministic.
func TestDeterminism(t *testing.T) {
var firstOutput string
// Set math/rand's seed for the sake of debugging this test.
// (It isn't strictly necessary).
mrand.Seed(1)
for i := 0; i < 100; i++ {
output := testThemAll()
if i == 0 {
firstOutput = output
} else {
if firstOutput != output {
t.Errorf("Run #%d's output was different from first run.\nfirst: %v\nlast: %v",
i, firstOutput, output)
}
}
}
}
func testThemAll() string {
// Such determinism.
grand.reset(1)
// Use it.
out := new(bytes.Buffer)
perm := RandPerm(10)
blob, _ := json.Marshal(perm)
fmt.Fprintf(out, "perm: %s\n", blob)
fmt.Fprintf(out, "randInt: %d\n", RandInt())
fmt.Fprintf(out, "randUint: %d\n", RandUint())
fmt.Fprintf(out, "randIntn: %d\n", RandIntn(97))
fmt.Fprintf(out, "randInt31: %d\n", RandInt31())
fmt.Fprintf(out, "randInt32: %d\n", RandInt32())
fmt.Fprintf(out, "randInt63: %d\n", RandInt63())
fmt.Fprintf(out, "randInt64: %d\n", RandInt64())
fmt.Fprintf(out, "randUint32: %d\n", RandUint32())
fmt.Fprintf(out, "randUint64: %d\n", RandUint64())
return out.String()
}
func TestRngConcurrencySafety(t *testing.T) {
var wg sync.WaitGroup
for i := 0; i < 100; i++ {
wg.Add(1)
go func() {
defer wg.Done()
_ = RandUint64()
<-time.After(time.Millisecond * time.Duration(RandIntn(100)))
_ = RandPerm(3)
}()
}
wg.Wait()
}
func BenchmarkRandBytes10B(b *testing.B) {
benchmarkRandBytes(b, 10)
}
func BenchmarkRandBytes100B(b *testing.B) {
benchmarkRandBytes(b, 100)
}
func BenchmarkRandBytes1KiB(b *testing.B) {
benchmarkRandBytes(b, 1024)
}
func BenchmarkRandBytes10KiB(b *testing.B) {
benchmarkRandBytes(b, 10*1024)
}
func BenchmarkRandBytes100KiB(b *testing.B) {
benchmarkRandBytes(b, 100*1024)
}
func BenchmarkRandBytes1MiB(b *testing.B) {
benchmarkRandBytes(b, 1024*1024)
}
func benchmarkRandBytes(b *testing.B, n int) {
for i := 0; i < b.N; i++ {
_ = RandBytes(n)
}
b.ReportAllocs()
}