48 lines
943 B
Go
48 lines
943 B
Go
package xrand
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import (
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"crypto/rand"
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"fmt"
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"math/big"
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"strings"
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)
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// Bytes generates random bytes with length n.
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func Bytes(n int) []byte {
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b := make([]byte, n)
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_, err := rand.Reader.Read(b)
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if err != nil {
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panic(fmt.Sprintf("failed to generate rand bytes: %v", err))
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}
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return b
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}
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// String generates a random string with length n.
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func String(n int) string {
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s := strings.ToValidUTF8(string(Bytes(n)), "_")
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s = strings.ReplaceAll(s, "\x00", "_")
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if len(s) > n {
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return s[:n]
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}
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if len(s) < n {
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// Pad with =
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extra := n - len(s)
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return s + strings.Repeat("=", extra)
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}
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return s
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}
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// Bool returns a randomly generated boolean.
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func Bool() bool {
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return Int(2) == 1
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}
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// Int returns a randomly generated integer between [0, max).
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func Int(max int) int {
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x, err := rand.Int(rand.Reader, big.NewInt(int64(max)))
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if err != nil {
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panic(fmt.Sprintf("failed to get random int: %v", err))
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}
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return int(x.Int64())
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}
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