--- /dev/null
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that random number sequences generated by a specific seed
+// do not change from version to version.
+//
+// Do NOT make changes to the golden outputs. If bugs need to be fixed
+// in the underlying code, find ways to fix them that do not affect the
+// outputs.
+
+package rand_test
+
+import (
+ "flag"
+ "fmt"
+ . "math/rand"
+ "reflect"
+ "testing"
+)
+
+var printgolden = flag.Bool("printgolden", false, "print golden results for regression test")
+
+func TestRegress(t *testing.T) {
+ var int32s = []int32{1, 10, 32, 1 << 20, 1<<20 + 1, 1000000000, 1 << 30, 1<<31 - 2, 1<<31 - 1}
+ var int64s = []int64{1, 10, 32, 1 << 20, 1<<20 + 1, 1000000000, 1 << 30, 1<<31 - 2, 1<<31 - 1, 1000000000000000000, 1 << 60, 1<<63 - 2, 1<<63 - 1}
+ var permSizes = []int{0, 1, 5, 8, 9, 10, 16}
+ r := New(NewSource(0))
+
+ rv := reflect.ValueOf(r)
+ n := rv.NumMethod()
+ p := 0
+ if *printgolden {
+ fmt.Printf("var regressGolden = []interface{}{\n")
+ }
+ for i := 0; i < n; i++ {
+ m := rv.Type().Method(i)
+ mv := rv.Method(i)
+ mt := mv.Type()
+ if mt.NumOut() == 0 {
+ continue
+ }
+ if mt.NumOut() != 1 {
+ t.Fatalf("unexpected result count for r.%s", m.Name)
+ }
+ r.Seed(0)
+ for repeat := 0; repeat < 20; repeat++ {
+ var args []reflect.Value
+ var argstr string
+ if mt.NumIn() == 1 {
+ var x interface{}
+ switch mt.In(0).Kind() {
+ default:
+ t.Fatalf("unexpected argument type for r.%s", m.Name)
+
+ case reflect.Int:
+ if m.Name == "Perm" {
+ x = permSizes[repeat%len(permSizes)]
+ break
+ }
+ big := int64s[repeat%len(int64s)]
+ if int64(int(big)) != big {
+ r.Int63n(big) // what would happen on 64-bit machine, to keep stream in sync
+ if *printgolden {
+ fmt.Printf("\tskipped, // must run printgolden on 64-bit machine\n")
+ }
+ p++
+ continue
+ }
+ x = int(big)
+
+ case reflect.Int32:
+ x = int32s[repeat%len(int32s)]
+
+ case reflect.Int64:
+ x = int64s[repeat%len(int64s)]
+ }
+ argstr = fmt.Sprint(x)
+ args = append(args, reflect.ValueOf(x))
+ }
+ out := mv.Call(args)[0].Interface()
+ if m.Name == "Int" || m.Name == "Intn" {
+ out = int64(out.(int))
+ }
+ if *printgolden {
+ var val string
+ big := int64(1 << 60)
+ if int64(int(big)) != big && (m.Name == "Int" || m.Name == "Intn") {
+ // 32-bit machine cannot print 64-bit results
+ val = "truncated"
+ } else if reflect.TypeOf(out).Kind() == reflect.Slice {
+ val = fmt.Sprintf("%#v", out)
+ } else {
+ val = fmt.Sprintf("%T(%v)", out, out)
+ }
+ fmt.Printf("\t%s, // %s(%s)\n", val, m.Name, argstr)
+ } else {
+ want := regressGolden[p]
+ if m.Name == "Int" {
+ want = int64(int(uint(want.(int64)) << 1 >> 1))
+ }
+ if !reflect.DeepEqual(out, want) {
+ t.Errorf("r.%s(%s) = %v, want %v", m.Name, argstr, out, want)
+ }
+ }
+ p++
+ }
+ }
+ if *printgolden {
+ fmt.Printf("}\n")
+ }
+}
+
+var regressGolden = []interface{}{
+ float64(4.668112973579268), // ExpFloat64()
+ float64(0.1601593871172866), // ExpFloat64()
+ float64(3.0465834105636), // ExpFloat64()
+ float64(0.06385839451671879), // ExpFloat64()
+ float64(1.8578917487258961), // ExpFloat64()
+ float64(0.784676123472182), // ExpFloat64()
+ float64(0.11225477361256932), // ExpFloat64()
+ float64(0.20173283329802255), // ExpFloat64()
+ float64(0.3468619496201105), // ExpFloat64()
+ float64(0.35601103454384536), // ExpFloat64()
+ float64(0.888376329507869), // ExpFloat64()
+ float64(1.4081362450365698), // ExpFloat64()
+ float64(1.0077753823151994), // ExpFloat64()
+ float64(0.23594100766227588), // ExpFloat64()
+ float64(2.777245612300007), // ExpFloat64()
+ float64(0.5202997830662377), // ExpFloat64()
+ float64(1.2842705247770294), // ExpFloat64()
+ float64(0.030307408362776206), // ExpFloat64()
+ float64(2.204156824853721), // ExpFloat64()
+ float64(2.09891923895058), // ExpFloat64()
+ float32(0.94519615), // Float32()
+ float32(0.24496509), // Float32()
+ float32(0.65595627), // Float32()
+ float32(0.05434384), // Float32()
+ float32(0.3675872), // Float32()
+ float32(0.28948045), // Float32()
+ float32(0.1924386), // Float32()
+ float32(0.65533215), // Float32()
+ float32(0.8971697), // Float32()
+ float32(0.16735445), // Float32()
+ float32(0.28858566), // Float32()
+ float32(0.9026048), // Float32()
+ float32(0.84978026), // Float32()
+ float32(0.2730468), // Float32()
+ float32(0.6090802), // Float32()
+ float32(0.253656), // Float32()
+ float32(0.7746542), // Float32()
+ float32(0.017480763), // Float32()
+ float32(0.78707397), // Float32()
+ float32(0.7993937), // Float32()
+ float64(0.9451961492941164), // Float64()
+ float64(0.24496508529377975), // Float64()
+ float64(0.6559562651954052), // Float64()
+ float64(0.05434383959970039), // Float64()
+ float64(0.36758720663245853), // Float64()
+ float64(0.2894804331565928), // Float64()
+ float64(0.19243860967493215), // Float64()
+ float64(0.6553321508148324), // Float64()
+ float64(0.897169713149801), // Float64()
+ float64(0.16735444255905835), // Float64()
+ float64(0.2885856518054551), // Float64()
+ float64(0.9026048462705047), // Float64()
+ float64(0.8497802817628735), // Float64()
+ float64(0.2730468047134829), // Float64()
+ float64(0.6090801919903561), // Float64()
+ float64(0.25365600644283687), // Float64()
+ float64(0.7746542391859803), // Float64()
+ float64(0.017480762156647272), // Float64()
+ float64(0.7870739563039942), // Float64()
+ float64(0.7993936979594545), // Float64()
+ int64(8717895732742165505), // Int()
+ int64(2259404117704393152), // Int()
+ int64(6050128673802995827), // Int()
+ int64(501233450539197794), // Int()
+ int64(3390393562759376202), // Int()
+ int64(2669985732393126063), // Int()
+ int64(1774932891286980153), // Int()
+ int64(6044372234677422456), // Int()
+ int64(8274930044578894929), // Int()
+ int64(1543572285742637646), // Int()
+ int64(2661732831099943416), // Int()
+ int64(8325060299420976708), // Int()
+ int64(7837839688282259259), // Int()
+ int64(2518412263346885298), // Int()
+ int64(5617773211005988520), // Int()
+ int64(2339563716805116249), // Int()
+ int64(7144924247938981575), // Int()
+ int64(161231572858529631), // Int()
+ int64(7259475919510918339), // Int()
+ int64(7373105480197164748), // Int()
+ int32(2029793274), // Int31()
+ int32(526058514), // Int31()
+ int32(1408655353), // Int31()
+ int32(116702506), // Int31()
+ int32(789387515), // Int31()
+ int32(621654496), // Int31()
+ int32(413258767), // Int31()
+ int32(1407315077), // Int31()
+ int32(1926657288), // Int31()
+ int32(359390928), // Int31()
+ int32(619732968), // Int31()
+ int32(1938329147), // Int31()
+ int32(1824889259), // Int31()
+ int32(586363548), // Int31()
+ int32(1307989752), // Int31()
+ int32(544722126), // Int31()
+ int32(1663557311), // Int31()
+ int32(37539650), // Int31()
+ int32(1690228450), // Int31()
+ int32(1716684894), // Int31()
+ int32(0), // Int31n(1)
+ int32(4), // Int31n(10)
+ int32(25), // Int31n(32)
+ int32(310570), // Int31n(1048576)
+ int32(857611), // Int31n(1048577)
+ int32(621654496), // Int31n(1000000000)
+ int32(413258767), // Int31n(1073741824)
+ int32(1407315077), // Int31n(2147483646)
+ int32(1926657288), // Int31n(2147483647)
+ int32(0), // Int31n(1)
+ int32(8), // Int31n(10)
+ int32(27), // Int31n(32)
+ int32(367019), // Int31n(1048576)
+ int32(209005), // Int31n(1048577)
+ int32(307989752), // Int31n(1000000000)
+ int32(544722126), // Int31n(1073741824)
+ int32(1663557311), // Int31n(2147483646)
+ int32(37539650), // Int31n(2147483647)
+ int32(0), // Int31n(1)
+ int32(4), // Int31n(10)
+ int64(8717895732742165505), // Int63()
+ int64(2259404117704393152), // Int63()
+ int64(6050128673802995827), // Int63()
+ int64(501233450539197794), // Int63()
+ int64(3390393562759376202), // Int63()
+ int64(2669985732393126063), // Int63()
+ int64(1774932891286980153), // Int63()
+ int64(6044372234677422456), // Int63()
+ int64(8274930044578894929), // Int63()
+ int64(1543572285742637646), // Int63()
+ int64(2661732831099943416), // Int63()
+ int64(8325060299420976708), // Int63()
+ int64(7837839688282259259), // Int63()
+ int64(2518412263346885298), // Int63()
+ int64(5617773211005988520), // Int63()
+ int64(2339563716805116249), // Int63()
+ int64(7144924247938981575), // Int63()
+ int64(161231572858529631), // Int63()
+ int64(7259475919510918339), // Int63()
+ int64(7373105480197164748), // Int63()
+ int64(0), // Int63n(1)
+ int64(2), // Int63n(10)
+ int64(19), // Int63n(32)
+ int64(959842), // Int63n(1048576)
+ int64(688912), // Int63n(1048577)
+ int64(393126063), // Int63n(1000000000)
+ int64(89212473), // Int63n(1073741824)
+ int64(834026388), // Int63n(2147483646)
+ int64(1577188963), // Int63n(2147483647)
+ int64(543572285742637646), // Int63n(1000000000000000000)
+ int64(355889821886249464), // Int63n(1152921504606846976)
+ int64(8325060299420976708), // Int63n(9223372036854775806)
+ int64(7837839688282259259), // Int63n(9223372036854775807)
+ int64(0), // Int63n(1)
+ int64(0), // Int63n(10)
+ int64(25), // Int63n(32)
+ int64(679623), // Int63n(1048576)
+ int64(882178), // Int63n(1048577)
+ int64(510918339), // Int63n(1000000000)
+ int64(782454476), // Int63n(1073741824)
+ int64(0), // Intn(1)
+ int64(4), // Intn(10)
+ int64(25), // Intn(32)
+ int64(310570), // Intn(1048576)
+ int64(857611), // Intn(1048577)
+ int64(621654496), // Intn(1000000000)
+ int64(413258767), // Intn(1073741824)
+ int64(1407315077), // Intn(2147483646)
+ int64(1926657288), // Intn(2147483647)
+ int64(543572285742637646), // Intn(1000000000000000000)
+ int64(355889821886249464), // Intn(1152921504606846976)
+ int64(8325060299420976708), // Intn(9223372036854775806)
+ int64(7837839688282259259), // Intn(9223372036854775807)
+ int64(0), // Intn(1)
+ int64(2), // Intn(10)
+ int64(14), // Intn(32)
+ int64(515775), // Intn(1048576)
+ int64(839455), // Intn(1048577)
+ int64(690228450), // Intn(1000000000)
+ int64(642943070), // Intn(1073741824)
+ float64(-0.28158587086436215), // NormFloat64()
+ float64(0.570933095808067), // NormFloat64()
+ float64(-1.6920196326157044), // NormFloat64()
+ float64(0.1996229111693099), // NormFloat64()
+ float64(1.9195199291234621), // NormFloat64()
+ float64(0.8954838794918353), // NormFloat64()
+ float64(0.41457072128813166), // NormFloat64()
+ float64(-0.48700161491544713), // NormFloat64()
+ float64(-0.1684059662402393), // NormFloat64()
+ float64(0.37056410998929545), // NormFloat64()
+ float64(1.0156889027029008), // NormFloat64()
+ float64(-0.5174422210625114), // NormFloat64()
+ float64(-0.5565834214413804), // NormFloat64()
+ float64(0.778320596648391), // NormFloat64()
+ float64(-1.8970718197702225), // NormFloat64()
+ float64(0.5229525761688676), // NormFloat64()
+ float64(-1.5515595563231523), // NormFloat64()
+ float64(0.0182029289376123), // NormFloat64()
+ float64(-0.6820951356608795), // NormFloat64()
+ float64(-0.5987943422687668), // NormFloat64()
+ []int{}, // Perm(0)
+ []int{0}, // Perm(1)
+ []int{0, 4, 1, 3, 2}, // Perm(5)
+ []int{3, 1, 0, 4, 7, 5, 2, 6}, // Perm(8)
+ []int{5, 0, 3, 6, 7, 4, 2, 1, 8}, // Perm(9)
+ []int{4, 5, 0, 2, 6, 9, 3, 1, 8, 7}, // Perm(10)
+ []int{14, 2, 0, 8, 3, 5, 13, 12, 1, 4, 6, 7, 11, 9, 15, 10}, // Perm(16)
+ []int{}, // Perm(0)
+ []int{0}, // Perm(1)
+ []int{3, 0, 1, 2, 4}, // Perm(5)
+ []int{5, 1, 2, 0, 4, 7, 3, 6}, // Perm(8)
+ []int{4, 0, 6, 8, 1, 5, 2, 7, 3}, // Perm(9)
+ []int{8, 6, 1, 7, 5, 4, 3, 2, 9, 0}, // Perm(10)
+ []int{0, 3, 13, 2, 15, 4, 10, 1, 8, 14, 7, 6, 12, 9, 5, 11}, // Perm(16)
+ []int{}, // Perm(0)
+ []int{0}, // Perm(1)
+ []int{0, 4, 2, 1, 3}, // Perm(5)
+ []int{2, 1, 7, 0, 6, 3, 4, 5}, // Perm(8)
+ []int{8, 7, 5, 3, 4, 6, 0, 1, 2}, // Perm(9)
+ []int{1, 0, 2, 5, 7, 6, 9, 8, 3, 4}, // Perm(10)
+ uint32(4059586549), // Uint32()
+ uint32(1052117029), // Uint32()
+ uint32(2817310706), // Uint32()
+ uint32(233405013), // Uint32()
+ uint32(1578775030), // Uint32()
+ uint32(1243308993), // Uint32()
+ uint32(826517535), // Uint32()
+ uint32(2814630155), // Uint32()
+ uint32(3853314576), // Uint32()
+ uint32(718781857), // Uint32()
+ uint32(1239465936), // Uint32()
+ uint32(3876658295), // Uint32()
+ uint32(3649778518), // Uint32()
+ uint32(1172727096), // Uint32()
+ uint32(2615979505), // Uint32()
+ uint32(1089444252), // Uint32()
+ uint32(3327114623), // Uint32()
+ uint32(75079301), // Uint32()
+ uint32(3380456901), // Uint32()
+ uint32(3433369789), // Uint32()
+}