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author | Josh Suereth <Joshua.Suereth@gmail.com> | 2012-08-30 05:02:48 -0700 |
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committer | Josh Suereth <Joshua.Suereth@gmail.com> | 2012-08-30 05:02:48 -0700 |
commit | f1b5332150ad37a99b61ba0ba5858bc75eb13c9e (patch) | |
tree | 2703f00a9bc691a08200655b0104acf52a99fad4 /test/files/run | |
parent | 51c94a2a2ee78e23491a29a971c9f7469b221cf5 (diff) | |
parent | 94888cf69bfe6e7d2ce65427715e4d57e6da3f85 (diff) | |
download | scala-f1b5332150ad37a99b61ba0ba5858bc75eb13c9e.tar.gz scala-f1b5332150ad37a99b61ba0ba5858bc75eb13c9e.tar.bz2 scala-f1b5332150ad37a99b61ba0ba5858bc75eb13c9e.zip |
Merge pull request #1160 from rklaehn/SI-6220
Si 6220
Diffstat (limited to 'test/files/run')
-rw-r--r-- | test/files/run/t6220.scala | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/test/files/run/t6220.scala b/test/files/run/t6220.scala new file mode 100644 index 0000000000..834b692f43 --- /dev/null +++ b/test/files/run/t6220.scala @@ -0,0 +1,92 @@ +import scala.collection.immutable._ + +object Test extends App { + + // finds an int x such that improved(x) differs in the first bit to improved(0), + // which is the worst case for the HashTrieSet + def findWorstCaseInts() { + // copy of improve from HashSet + def improve(hcode: Int) = { + var h: Int = hcode + ~(hcode << 9) + h = h ^ (h >>> 14) + h = h + (h << 4) + h ^ (h >>> 10) + } + + // find two hashes which have a large separation + val x = 0 + var y = 1 + val ix = improve(x) + while(y!=0 && improve(y)!=ix+(1<<31)) + y+=1 + printf("%s %s %x %x\n",x,y,improve(x), improve(y)) + } + // this is not done every test run since it would slow down ant test.suite too much. + // findWorstCaseInts() + + // two numbers that are immediately adiacent when fed through HashSet.improve + val h0 = 0 + val h1 = 1270889724 + + // h is the hashcode, i is ignored for the hashcode but relevant for equality + case class Collision(h:Int, i:Int) { + override def hashCode = h + } + val a = Collision(h0,0) + val b = Collision(h0,1) + val c = Collision(h1,0) + + // create a HashSetCollision1 + val x = HashSet(a) + b + if(x.getClass.getSimpleName != "HashSetCollision1") + println("x should be a collision") + StructureTests.validate(x) + // StructureTests.printStructure(x) + require(x.size==2 && x.contains(a) && x.contains(b)) + + // go from a HashSetCollision1 to a HashTrieSet with maximum depth + val y = x + c + if(y.getClass.getSimpleName != "HashTrieSet") + println("y should be a HashTrieSet") + StructureTests.validate(y) + // StructureTests.printStructure(y) + require(y.size==3 && y.contains(a) && y.contains(b) && y.contains(c)) + + // go from a HashSet1 directly to a HashTrieSet with maximum depth + val z = HashSet(a) + c + if(y.getClass.getSimpleName != "HashTrieSet") + println("y should be a HashTrieSet") + StructureTests.validate(z) + // StructureTests.printStructure(z) + require(z.size == 2 && z.contains(a) && z.contains(c)) +} + +package scala.collection.immutable { + object StructureTests { + def printStructure(x:HashSet[_], prefix:String="") { + x match { + case m:HashSet.HashTrieSet[_] => + println(prefix+m.getClass.getSimpleName + " " + m.size) + m.elems.foreach(child => printStructure(child, prefix + " ")) + case m:HashSet.HashSetCollision1[_] => + println(prefix+m.getClass.getSimpleName + " " + m.ks.size) + case m:HashSet.HashSet1[_] => + println(prefix+m.getClass.getSimpleName + " " + m.head) + case _ => + println(prefix+"empty") + } + } + + def validate(x:HashSet[_]) { + x match { + case m:HashSet.HashTrieSet[_] => + require(m.elems.size>1 || (m.elems.size==1 && m.elems(0).isInstanceOf[HashSet.HashTrieSet[_]])) + m.elems.foreach(validate _) + case m:HashSet.HashSetCollision1[_] => + require(m.ks.size>1) + case m:HashSet.HashSet1[_] => + case _ => + } + } + } +} |