For testing purposes, you may want to supply random input to a method, but Alphanumeric generators like scala.util.Random.alphanumeric don't cover the full possible input in many cases.
What is the best way to generate random unicode strings of a given length?
It can be done without mutable buffers or variables.
import java.lang.Character
import util.Random
def randomUnicodeString(length: Int) =
LazyList.continually(Random.nextInt(0xFFFF))
.collect{case c if Character.isDefined(c) => c.toChar}
.take(length)
.mkString
LazyList with StreamConsider ScalaCheck generators, for example
import org.scalatest._
import org.scalatestplus.scalacheck.ScalaCheckDrivenPropertyChecks
import org.scalacheck.{Arbitrary, Gen}
class AlphanumericGeneratorSpec extends FlatSpec with Matchers with ScalaCheckDrivenPropertyChecks {
"Arbitrary.arbString" should "generate arbitrary strings" in {
forAll(Arbitrary.arbString.arbitrary) { s =>
println(s)
}
}
}
outputs something like
⦍鸟㗴鲪ᬎ㺥
䊪仍ୁ㕃댊벝蛎瓊倊錾釨㚺㥌ੜ
仁벵ຝ洱霷쀙쵟㹳灢瑤쌴
詢蓫䑽ᵋ앹䦆딂ᄬ鉖
醃䦼컠᳞遱掊醌涰ᚕ苇泟Ễ㒪뭩綗ᄍ䉱屮藓䦆䜜㴹煉ں㸲䛊ᓠ셴켶䦖垯ᡤ卆婱羘畕⁋䢅ﯫ訆݊ⵕ건
썁㙁䠼臩蚁䬣ݍ⓸⤵犕꺭ཛྷ잁闓襥鯽啌ꟴ翏㫺ܪሷ뢛快腊机ᰵ蟽ﳥɴ馣䪚軇鿾㹄Ꝓ㿈뿭땧颟ᜒ纈ꔧ毚뒢兊屼
矵귳옘䕌Ⱌ｀凣쐕튌ằ惿獄ꍝ䫗끒뮌錑㶩ዒ絽鹣煋襁ꨔᔵ팋屜姙ꙇᡛ뾗꘎焑酸ಹ乵텣쳊疟䉴투꿠㱎ᅧ텎ᑽﹽ跡
橛櫯ꆠ葲逊ᵈ엦災盨捻棉䟔縆⦽㯠侄ᙑד볓끀謹翆滳ץ픎Ꝛ餮范샥➮⊠㇔鐿詥ꊔ텦䟑徜ꮉ绳䜁빎학⮴䑢悋铃揍挛⭂장踛ﻥ螴阶ퟠ햇
ᶭ䯵꧓擃轤ꦧꦛ
To set fixed size try
def arbUnicodeGen(size: Int) =
Gen.listOfN(size, Arbitrary.arbChar.arbitrary).map(_.mkString)
and then
"arbUnicodeGen" should "generate fixed length arbitrary strings" in {
forAll(arbUnicodeGen(10)) { s =>
println(s)
}
}