--- /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/EconomicMapImplTest.java	Fri Feb 02 17:28:17 2018 -0800
@@ -0,0 +1,126 @@
+/*
+ * 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.Arrays;
+import java.util.Iterator;
+
+import org.graalvm.collections.EconomicMap;
+import org.graalvm.collections.EconomicSet;
+import org.graalvm.collections.Equivalence;
+import org.graalvm.collections.UnmodifiableEconomicSet;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class EconomicMapImplTest {
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testRemoveNull() {
+        EconomicMap<Integer, Integer> map = EconomicMap.create(10);
+        map.removeKey(null);
+    }
+
+    @Test
+    public void testInitFromHashSet() {
+        UnmodifiableEconomicSet<Integer> set = new UnmodifiableEconomicSet<Integer>() {
+
+            @Override
+            public boolean contains(Integer element) {
+                return element == 0;
+            }
+
+            @Override
+            public int size() {
+                return 1;
+            }
+
+            @Override
+            public boolean isEmpty() {
+                return false;
+            }
+
+            @Override
+            public Iterator<Integer> iterator() {
+                return new Iterator<Integer>() {
+
+                    private boolean visited = false;
+
+                    @Override
+                    public boolean hasNext() {
+                        return !visited;
+                    }
+
+                    @Override
+                    public Integer next() {
+                        if (visited) {
+                            return null;
+                        } else {
+                            visited = true;
+                            return 1;
+                        }
+                    }
+                };
+            }
+        };
+
+        EconomicSet<Integer> newSet = EconomicSet.create(Equivalence.DEFAULT, set);
+        Assert.assertEquals(newSet.size(), 1);
+    }
+
+    @Test
+    public void testCopyHash() {
+        EconomicSet<Integer> set = EconomicSet.create(Equivalence.IDENTITY);
+        set.addAll(Arrays.asList(0, 1, 2, 3, 4, 5, 6, 7, 8, 9));
+        EconomicSet<Integer> newSet = EconomicSet.create(Equivalence.IDENTITY, set);
+        Assert.assertEquals(newSet.size(), 10);
+        newSet.remove(8);
+        newSet.remove(9);
+        Assert.assertEquals(newSet.size(), 8);
+    }
+
+    @Test
+    public void testNewEquivalence() {
+        EconomicSet<Integer> set = EconomicSet.create(new Equivalence() {
+            @Override
+            public boolean equals(Object a, Object b) {
+                return false;
+            }
+
+            @Override
+            public int hashCode(Object o) {
+                return 0;
+            }
+        });
+        set.addAll(Arrays.asList(0, 1, 2, 3, 4, 5, 6, 7, 8, 9));
+        Assert.assertTrue(set.add(new Integer(0)));
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testMapPutNull() {
+        EconomicMap<Integer, Integer> map = EconomicMap.create();
+        map.put(null, null);
+    }
+
+}