--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.collections.test/src/org/graalvm/collections/test/EconomicSetTest.java	Fri Feb 02 17:28:17 2018 -0800
@@ -0,0 +1,148 @@
+/*
+ * Copyright (c) 2017, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package org.graalvm.collections.test;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+
+import org.graalvm.collections.EconomicSet;
+import org.graalvm.collections.Equivalence;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class EconomicSetTest {
+
+    @Test
+    public void testUtilities() {
+        EconomicSet<Integer> set = EconomicSet.create(0);
+        set.add(0);
+        Assert.assertTrue(set.add(1));
+        Assert.assertEquals(set.size(), 2);
+        Assert.assertFalse(set.add(1));
+        Assert.assertEquals(set.size(), 2);
+        set.remove(1);
+        Assert.assertEquals(set.size(), 1);
+        set.remove(2);
+        Assert.assertEquals(set.size(), 1);
+        Assert.assertTrue(set.add(1));
+        set.clear();
+        Assert.assertEquals(set.size(), 0);
+    }
+
+    @Test
+    public void testAddAll() {
+        EconomicSet<Integer> set = EconomicSet.create();
+        set.addAll(Arrays.asList(0, 1, 0));
+        Assert.assertEquals(set.size(), 2);
+
+        EconomicSet<Integer> newSet = EconomicSet.create();
+        newSet.addAll(Arrays.asList(1, 2));
+        Assert.assertEquals(newSet.size(), 2);
+        newSet.addAll(set);
+        Assert.assertEquals(newSet.size(), 3);
+    }
+
+    @Test
+    public void testRemoveAll() {
+        EconomicSet<Integer> set = EconomicSet.create();
+        set.addAll(Arrays.asList(0, 1));
+
+        set.removeAll(Arrays.asList(1, 2));
+        Assert.assertEquals(set.size(), 1);
+
+        set.removeAll(EconomicSet.create(set));
+        Assert.assertEquals(set.size(), 0);
+    }
+
+    @Test
+    public void testRetainAll() {
+        EconomicSet<Integer> set = EconomicSet.create();
+        set.addAll(Arrays.asList(0, 1, 2));
+
+        EconomicSet<Integer> newSet = EconomicSet.create();
+        newSet.addAll(Arrays.asList(2, 3));
+
+        set.retainAll(newSet);
+        Assert.assertEquals(set.size(), 1);
+    }
+
+    @Test
+    public void testToArray() {
+        EconomicSet<Integer> set = EconomicSet.create();
+        set.addAll(Arrays.asList(0, 1));
+        Assert.assertArrayEquals(set.toArray(new Integer[2]), new Integer[]{0, 1});
+    }
+
+    @Test
+    public void testToString() {
+        EconomicSet<Integer> set = EconomicSet.create();
+        set.addAll(Arrays.asList(0, 1));
+        Assert.assertEquals(set.toString(), "set(size=2, {0,1})");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testToUnalignedArray() {
+        Assert.assertArrayEquals(EconomicSet.create().toArray(new Integer[2]), new Integer[0]);
+    }
+
+    @Test
+    public void testSetRemoval() {
+        ArrayList<Integer> initialList = new ArrayList<>();
+        ArrayList<Integer> removalList = new ArrayList<>();
+        ArrayList<Integer> finalList = new ArrayList<>();
+        EconomicSet<Integer> set = EconomicSet.create(Equivalence.IDENTITY);
+        set.add(1);
+        set.add(2);
+        set.add(3);
+        set.add(4);
+        set.add(5);
+        set.add(6);
+        set.add(7);
+        set.add(8);
+        set.add(9);
+        Iterator<Integer> i1 = set.iterator();
+        while (i1.hasNext()) {
+            initialList.add(i1.next());
+        }
+        int size = 0;
+        Iterator<Integer> i2 = set.iterator();
+        while (i2.hasNext()) {
+            Integer elem = i2.next();
+            if (size++ < 8) {
+                i2.remove();
+            }
+            removalList.add(elem);
+        }
+        Iterator<Integer> i3 = set.iterator();
+        while (i3.hasNext()) {
+            finalList.add(i3.next());
+        }
+        Assert.assertEquals(initialList, removalList);
+        Assert.assertEquals(1, finalList.size());
+        Assert.assertEquals(new Integer(9), finalList.get(0));
+    }
+
+}