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import org.scalacheck._
import Prop._
import org.scalacheck.Gen._
import collection._
import collection.concurrent.TrieMap
case class Wrap(i: Int) {
override def hashCode = i // * 0x9e3775cd
}
/** A check mainly oriented towards checking snapshot correctness.
*/
object Test extends Properties("concurrent.TrieMap") {
/* generators */
val sizes = choose(0, 200000)
val threadCounts = choose(2, 16)
val threadCountsAndSizes = for {
p <- threadCounts
sz <- sizes
} yield (p, sz);
/* helpers */
def inParallel[T](totalThreads: Int)(body: Int => T): Seq[T] = {
val threads = for (idx <- 0 until totalThreads) yield new Thread {
setName("ParThread-" + idx)
private var res: T = _
override def run() {
res = body(idx)
}
def result = {
this.join()
res
}
}
threads foreach (_.start())
threads map (_.result)
}
def spawn[T](body: =>T): { def get: T } = {
val t = new Thread {
setName("SpawnThread")
private var res: T = _
override def run() {
res = body
}
def result = res
}
t.start()
new {
def get: T = {
t.join()
t.result
}
}
}
def elementRange(threadIdx: Int, totalThreads: Int, totalElems: Int): Range = {
val sz = totalElems
val idx = threadIdx
val p = totalThreads
val start = (sz / p) * idx + math.min(idx, sz % p)
val elems = (sz / p) + (if (idx < sz % p) 1 else 0)
val end = start + elems
(start until end)
}
def hasGrown[K, V](last: Map[K, V], current: Map[K, V]) = {
(last.size <= current.size) && {
last forall {
case (k, v) => current.get(k) == Some(v)
}
}
}
object err {
var buffer = new StringBuilder
def println(a: AnyRef) = buffer.append(a.toString).append("\n")
def clear() = buffer.clear()
def flush() = {
Console.out.println(buffer)
clear()
}
}
/* properties */
property("concurrent growing snapshots") = forAll(threadCounts, sizes) {
(numThreads, numElems) =>
val p = 3 //numThreads
val sz = 102 //numElems
val ct = new TrieMap[Wrap, Int]
// checker
val checker = spawn {
def check(last: Map[Wrap, Int], iterationsLeft: Int): Boolean = {
val current = ct.readOnlySnapshot()
if (!hasGrown(last, current)) false
else if (current.size >= sz) true
else if (iterationsLeft < 0) false
else check(current, iterationsLeft - 1)
}
check(ct.readOnlySnapshot(), 500)
}
// fillers
inParallel(p) {
idx =>
elementRange(idx, p, sz) foreach (i => ct.update(Wrap(i), i))
}
// wait for checker to finish
val growing = true//checker.get
val ok = growing && ((0 until sz) forall {
case i => ct.get(Wrap(i)) == Some(i)
})
ok
}
property("update") = forAll(sizes) {
(n: Int) =>
val ct = new TrieMap[Int, Int]
for (i <- 0 until n) ct(i) = i
(0 until n) forall {
case i => ct(i) == i
}
}
property("concurrent update") = forAll(threadCountsAndSizes) {
case (p, sz) =>
val ct = new TrieMap[Wrap, Int]
inParallel(p) {
idx =>
for (i <- elementRange(idx, p, sz)) ct(Wrap(i)) = i
}
(0 until sz) forall {
case i => ct(Wrap(i)) == i
}
}
property("concurrent remove") = forAll(threadCounts, sizes) {
(p, sz) =>
val ct = new TrieMap[Wrap, Int]
for (i <- 0 until sz) ct(Wrap(i)) = i
inParallel(p) {
idx =>
for (i <- elementRange(idx, p, sz)) ct.remove(Wrap(i))
}
(0 until sz) forall {
case i => ct.get(Wrap(i)) == None
}
}
property("concurrent putIfAbsent") = forAll(threadCounts, sizes) {
(p, sz) =>
val ct = new TrieMap[Wrap, Int]
val results = inParallel(p) {
idx =>
elementRange(idx, p, sz) find (i => ct.putIfAbsent(Wrap(i), i) != None)
}
(results forall (_ == None)) && ((0 until sz) forall {
case i => ct.get(Wrap(i)) == Some(i)
})
}
}
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