Style/rename internal rand (#701)

* style: rename internal/rand package to internal/xrand

* doc: internal package readme

* oops

channel.go

@@ -5,7 +5,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/samber/lo/internal/rand"
+	"github.com/samber/lo/internal/xrand"
 )
 
 // DispatchingStrategy is a function that distributes messages to channels.
@@ -92,7 +92,7 @@ func DispatchingStrategyRoundRobin[T any](msg T, index uint64, channels []<-chan
 // Play: https://go.dev/play/p/GEyGn3TdGk4
 func DispatchingStrategyRandom[T any](msg T, index uint64, channels []<-chan T) int {
 	for {
-		i := rand.IntN(len(channels))
+		i := xrand.IntN(len(channels))
 		if channelIsNotFull(channels[i]) {
 			return i
 		}
@@ -115,7 +115,7 @@ func DispatchingStrategyWeightedRandom[T any](weights []int) DispatchingStrategy
 
 	return func(msg T, index uint64, channels []<-chan T) int {
 		for {
-			i := seq[rand.IntN(len(seq))]
+			i := seq[xrand.IntN(len(seq))]
 			if channelIsNotFull(channels[i]) {
 				return i
 			}

find.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/samber/lo/internal/constraints"
-	"github.com/samber/lo/internal/rand"
+	"github.com/samber/lo/internal/xrand"
 )
 
 // IndexOf returns the index at which the first occurrence of a value is found in a slice or -1
@@ -660,7 +660,7 @@ type randomIntGenerator func(n int) int
 // Sample returns a random item from collection.
 // Play: https://go.dev/play/p/vCcSJbh5s6l
 func Sample[T any](collection []T) T {
-	result := SampleBy(collection, rand.IntN)
+	result := SampleBy(collection, xrand.IntN)
 	return result
 }
 
@@ -677,7 +677,7 @@ func SampleBy[T any](collection []T, randomIntGenerator randomIntGenerator) T {
 // Samples returns N random unique items from collection.
 // Play: https://go.dev/play/p/vCcSJbh5s6l
 func Samples[T any, Slice ~[]T](collection Slice, count int) Slice {
-	results := SamplesBy(collection, count, rand.IntN)
+	results := SamplesBy(collection, count, xrand.IntN)
 	return results
 }
 

internal/constraints/README.md

@@ -0,0 +1,4 @@
+
+# Constraints
+
+This package is for Go 1.18 retrocompatiblity purpose.

internal/xrand/ordered_go118.go

@@ -1,6 +1,6 @@
 //go:build !go1.22
 
-package rand
+package xrand
 
 import "math/rand"
 

internal/xrand/ordered_go122.go

@@ -1,6 +1,6 @@
 //go:build go1.22
 
-package rand
+package xrand
 
 import "math/rand/v2"
 

it/find.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/samber/lo"
 	"github.com/samber/lo/internal/constraints"
-	"github.com/samber/lo/internal/rand"
+	"github.com/samber/lo/internal/xrand"
 )
 
 // IndexOf returns the index at which the first occurrence of a value is found in a sequence or -1
@@ -453,7 +453,7 @@ func NthOrEmpty[T any, N constraints.Integer](collection iter.Seq[T], nth N) T {
 // Will iterate through the entire sequence and allocate a slice large enough to hold all elements.
 // Long input sequences can cause excessive memory usage.
 func Sample[T any](collection iter.Seq[T]) T {
-	return SampleBy(collection, rand.IntN)
+	return SampleBy(collection, xrand.IntN)
 }
 
 // SampleBy returns a random item from collection, using randomIntGenerator as the random index generator.
@@ -468,7 +468,7 @@ func SampleBy[T any](collection iter.Seq[T], randomIntGenerator func(int) int) T
 // Will iterate through the entire sequence and allocate a slice large enough to hold all elements.
 // Long input sequences can cause excessive memory usage.
 func Samples[T any, I ~func(func(T) bool)](collection I, count int) I {
-	return SamplesBy(collection, count, rand.IntN)
+	return SamplesBy(collection, count, xrand.IntN)
 }
 
 // SamplesBy returns N random unique items from collection, using randomIntGenerator as the random index generator.

it/find_test.go

@@ -4,11 +4,11 @@ package it
 
 import (
 	"iter"
-	"math/rand/v2"
 	"slices"
 	"testing"
 	"time"
 
+	"github.com/samber/lo/internal/xrand"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -687,8 +687,8 @@ func TestSampleBy(t *testing.T) {
 	t.Parallel()
 	is := assert.New(t)
 
-	result1 := SampleBy(values("a", "b", "c"), rand.IntN)
+	result1 := SampleBy(values("a", "b", "c"), xrand.IntN)
-	result2 := SampleBy(values[string](), rand.IntN)
+	result2 := SampleBy(values[string](), xrand.IntN)
 
 	is.True(Contains(values("a", "b", "c"), result1))
 	is.Empty(result2)
@@ -714,14 +714,14 @@ func TestSamplesBy(t *testing.T) {
 	t.Parallel()
 	is := assert.New(t)
 
-	result1 := SamplesBy(values("a", "b", "c"), 3, rand.IntN)
+	result1 := SamplesBy(values("a", "b", "c"), 3, xrand.IntN)
-	result2 := SamplesBy(values[string](), 3, rand.IntN)
+	result2 := SamplesBy(values[string](), 3, xrand.IntN)
 
 	is.ElementsMatch(slices.Collect(result1), []string{"a", "b", "c"})
 	is.Empty(slices.Collect(result2))
 
 	type myStrings iter.Seq[string]
 	allStrings := myStrings(values("", "foo", "bar"))
-	nonempty := SamplesBy(allStrings, 2, rand.IntN)
+	nonempty := SamplesBy(allStrings, 2, xrand.IntN)
 	is.IsType(nonempty, allStrings, "type preserved")
 }

mutable/slice.go

@@ -1,6 +1,6 @@
 package mutable
 
-import "github.com/samber/lo/internal/rand"
+import "github.com/samber/lo/internal/xrand"
 
 // Filter is a generic function that modifies the input slice in-place to contain only the elements
 // that satisfy the provided predicate function. The predicate function takes an element of the slice and its index,
@@ -55,7 +55,7 @@ func MapI[T any, Slice ~[]T](collection Slice, fn func(item T, index int) T) {
 // Shuffle returns a slice of shuffled values. Uses the Fisher-Yates shuffle algorithm.
 // Play: https://go.dev/play/p/2xb3WdLjeSJ
 func Shuffle[T any, Slice ~[]T](collection Slice) {
-	rand.Shuffle(len(collection), func(i, j int) {
+	xrand.Shuffle(len(collection), func(i, j int) {
 		collection[i], collection[j] = collection[j], collection[i]
 	})
 }

string.go

@@ -7,7 +7,7 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"github.com/samber/lo/internal/rand"
+	"github.com/samber/lo/internal/xrand"
 
 	"golang.org/x/text/cases"
 	"golang.org/x/text/language"
@@ -60,14 +60,14 @@ func RandomString(size int, charset []rune) string {
 	// Determine the corresponding bitmask,
 	// e.g., for 62 characters, the bitmask would be 111111.
 	var letterIDMask int64 = 1<<letterIDBits - 1
-	// Available count, since rand.Int64() returns a non-negative number, the first bit is fixed, so there are 63 random bits
+	// Available count, since xrand.Int64() returns a non-negative number, the first bit is fixed, so there are 63 random bits
 	// e.g., for 62 characters, this value is 10 (63 / 6).
 	letterIDMax := 63 / letterIDBits
 	// Generate the random string in a loop.
-	for i, cache, remain := size-1, rand.Int64(), letterIDMax; i >= 0; {
+	for i, cache, remain := size-1, xrand.Int64(), letterIDMax; i >= 0; {
 		// Regenerate the random number if all available bits have been used
 		if remain == 0 {
-			cache, remain = rand.Int64(), letterIDMax
+			cache, remain = xrand.Int64(), letterIDMax
 		}
 		// Select a character from the charset
 		if idx := int(cache & letterIDMask); idx < len(charset) {