SI-7938 - parallel collections should use default ExecutionContext

Parallel collections now use `scala.concurrent.ExecutionContext`
by default.

The `ExecutionContextTaskSupport` is optimized to use the
`ForkJoinPool` underlying the `ExecutionContext` if possible.
Otherwise, a fallback `TaskSupport` that creates a reduction tree and
execute an operation through `Future`s is used.

1 files changed, 41 insertions, 24 deletions

diff --git a/test/files/scalacheck/parallel-collections/pc.scala b/test/files/scalacheck/parallel-collections/pc.scala
index c588692fd2..a3c1df4054 100644
--- a/test/files/scalacheck/parallel-collections/pc.scala
+++ b/test/files/scalacheck/parallel-collections/pc.scala
@@ -6,35 +6,52 @@
 import org.scalacheck._
 import scala.collection.parallel._
 
-class ParCollProperties extends Properties("Parallel collections") {
-  /*   Collections   */
+// package here to be able access the package-private implementation and shutdown the pool
+package scala {
 
-  // parallel arrays
-  include(mutable.IntParallelArrayCheck)
+  class ParCollProperties extends Properties("Parallel collections") {
+  
+    def includeAllTestsWith(support: TaskSupport) {
+      // parallel arrays with default task support
+      include(new mutable.IntParallelArrayCheck(support))
+    
+      // parallel ranges
+      include(new immutable.ParallelRangeCheck(support))
+    
+      // parallel immutable hash maps (tries)
+      include(new immutable.IntIntParallelHashMapCheck(support))
+    
+      // parallel immutable hash sets (tries)
+      include(new immutable.IntParallelHashSetCheck(support))
+    
+      // parallel mutable hash maps (tables)
+      include(new mutable.IntIntParallelHashMapCheck(support))
+    
+      // parallel ctrie
+      include(new mutable.IntIntParallelConcurrentTrieMapCheck(support))
+    
+      // parallel mutable hash sets (tables)
+      include(new mutable.IntParallelHashSetCheck(support))
+    
+      // parallel vectors
+      include(new immutable.IntParallelVectorCheck(support))
+    }
+  
+    includeAllTestsWith(defaultTaskSupport)
+  
+    val ec = scala.concurrent.ExecutionContext.fromExecutorService(java.util.concurrent.Executors.newFixedThreadPool(5))
+    val ectasks = new collection.parallel.ExecutionContextTaskSupport(ec)
+    includeAllTestsWith(ectasks)
 
-  // parallel ranges
-  include(immutable.ParallelRangeCheck)
-
-  // parallel immutable hash maps (tries)
-  include(immutable.IntIntParallelHashMapCheck)
-
-  // parallel immutable hash sets (tries)
-  include(immutable.IntParallelHashSetCheck)
-
-  // parallel mutable hash maps (tables)
-  include(mutable.IntIntParallelHashMapCheck)
-
-  // parallel ctrie
-  include(mutable.IntIntParallelConcurrentTrieMapCheck)
-
-  // parallel mutable hash sets (tables)
-  include(mutable.IntParallelHashSetCheck)
+    // no post test hooks in scalacheck, so cannot do:
+    // ec.shutdown()
+  
+  }
 
-  // parallel vectors
-  include(immutable.IntParallelVectorCheck)
 }
 
-object Test extends ParCollProperties {
+
+object Test extends scala.ParCollProperties {
   /*
   def main(args: Array[String]) {
     val pc = new ParCollProperties