math/rand/v2: remove Rand.Seed

Removing Rand.Seed lets us remove lockedSource as well, along with the ambiguity in globalRand about which source to use. For #61716. Change-Id: Ibe150520dd1e7dd87165eacaebe9f0c2daeaedfd Reviewed-on: https://go-review.googlesource.com/c/go/+/502498 Reviewed-by: Dmitri Shuralyov <[email protected]> Reviewed-by: Rob Pike <[email protected]> LUCI-TryBot-Result: Go LUCI <[email protected]> Auto-Submit: Russ Cox <[email protected]>
golang · Oct 30, 2023 · 1cc5b34 · 1cc5b34
1 parent 48bd1fc
commit 1cc5b34
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Showing 5 changed files with 25 additions and 315 deletions.
diff --git a/api/next/61716.txt b/api/next/61716.txt
@@ -12,8 +12,6 @@ pkg math/rand/v2, func NewSource(int64) Source #61716
 pkg math/rand/v2, func NewZipf(*Rand, float64, float64, uint64) *Zipf #61716
 pkg math/rand/v2, func NormFloat64() float64 #61716
 pkg math/rand/v2, func Perm(int) []int #61716
-pkg math/rand/v2, func Seed //deprecated #61716
-pkg math/rand/v2, func Seed(int64) #61716
 pkg math/rand/v2, func Shuffle(int, func(int, int)) #61716
 pkg math/rand/v2, func Uint32() uint32 #61716
 pkg math/rand/v2, func Uint64() uint64 #61716
@@ -28,17 +26,14 @@ pkg math/rand/v2, method (*Rand) Int64N(int64) int64 #61716
 pkg math/rand/v2, method (*Rand) IntN(int) int #61716
 pkg math/rand/v2, method (*Rand) NormFloat64() float64 #61716
 pkg math/rand/v2, method (*Rand) Perm(int) []int #61716
-pkg math/rand/v2, method (*Rand) Seed(int64) #61716
 pkg math/rand/v2, method (*Rand) Shuffle(int, func(int, int)) #61716
 pkg math/rand/v2, method (*Rand) Uint32() uint32 #61716
 pkg math/rand/v2, method (*Rand) Uint64() uint64 #61716
 pkg math/rand/v2, method (*Zipf) Uint64() uint64 #61716
 pkg math/rand/v2, type Rand struct #61716
-pkg math/rand/v2, type Source interface { Int64, Seed } #61716
+pkg math/rand/v2, type Source interface { Int64 } #61716
 pkg math/rand/v2, type Source interface, Int64() int64 #61716
-pkg math/rand/v2, type Source interface, Seed(int64) #61716
-pkg math/rand/v2, type Source64 interface { Int64, Seed, Uint64 } #61716
+pkg math/rand/v2, type Source64 interface { Int64, Uint64 } #61716
 pkg math/rand/v2, type Source64 interface, Int64() int64 #61716
-pkg math/rand/v2, type Source64 interface, Seed(int64) #61716
 pkg math/rand/v2, type Source64 interface, Uint64() uint64 #61716
 pkg math/rand/v2, type Zipf struct #61716
diff --git a/src/math/rand/v2/auto_test.go b/src/math/rand/v2/auto_test.go
@@ -16,20 +16,20 @@ import (
 func TestAuto(t *testing.T) {
 	// Pull out 10 int64s from the global source
 	// and then check that they don't appear in that
-	// order in the deterministic Seed(1) result.
+	// order in the deterministic seeded result.
 	var out []int64
 	for i := 0; i < 10; i++ {
 		out = append(out, Int64())
 	}
 
-	// Look for out in Seed(1)'s output.
+	// Look for out in seeded output.
 	// Strictly speaking, we should look for them in order,
 	// but this is good enough and not significantly more
 	// likely to have a false positive.
-	Seed(1)
+	r := New(NewSource(1))
 	found := 0
 	for i := 0; i < 1000; i++ {
-		x := Int64()
+		x := r.Int64()
 		if x == out[found] {
 			found++
 			if found == len(out) {

diff --git a/src/math/rand/v2/default_test.go b/src/math/rand/v2/default_test.go
diff --git a/src/math/rand/v2/race_test.go b/src/math/rand/v2/race_test.go
@@ -23,9 +23,8 @@ func TestConcurrent(t *testing.T) {
 	for i := 0; i < numRoutines; i++ {
 		go func(i int) {
 			defer wg.Done()
-			buf := make([]byte, 997)
+			var seed int64
 			for j := 0; j < numCycles; j++ {
-				var seed int64
 				seed += int64(ExpFloat64())
 				seed += int64(Float32())
 				seed += int64(Float64())
@@ -38,11 +37,8 @@ func TestConcurrent(t *testing.T) {
 				for _, p := range Perm(10) {
 					seed += int64(p)
 				}
-				for _, b := range buf {
-					seed += int64(b)
-				}
-				Seed(int64(i*j) * seed)
 			}
+			_ = seed
 		}(i)
 	}
 }