diff --git a/gson/src/test/java/com/google/gson/reflect/reflect/TypeTokenTest.java b/gson/src/test/java/com/google/gson/reflect/reflect/TypeTokenTest.java
new file mode 100644
index 00000000..a76d5612
--- /dev/null
+++ b/gson/src/test/java/com/google/gson/reflect/reflect/TypeTokenTest.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2010 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.gson.reflect;
+
+import java.lang.reflect.Type;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.RandomAccess;
+import java.util.Set;
+import junit.framework.TestCase;
+
+/**
+ * @author Jesse Wilson
+ */
+@SuppressWarnings({"UnusedDeclaration", "deprecation"})
+public final class TypeTokenTest extends TestCase {
+
+  List<Integer> listOfInteger = null;
+  List<Number> listOfNumber = null;
+  List<String> listOfString = null;
+  List<?> listOfUnknown = null;
+  List<Set<String>> listOfSetOfString = null;
+  List<Set<?>> listOfSetOfUnknown = null;
+
+  public void testIsAssignableFromRawTypes() {
+    assertTrue(TypeToken.get(Object.class).isAssignableFrom(String.class));
+    assertFalse(TypeToken.get(String.class).isAssignableFrom(Object.class));
+    assertTrue(TypeToken.get(RandomAccess.class).isAssignableFrom(ArrayList.class));
+    assertFalse(TypeToken.get(ArrayList.class).isAssignableFrom(RandomAccess.class));
+  }
+
+  public void testIsAssignableFromWithTypeParameters() throws Exception {
+    Type a = getClass().getDeclaredField("listOfInteger").getGenericType();
+    Type b = getClass().getDeclaredField("listOfNumber").getGenericType();
+    assertTrue(TypeToken.get(a).isAssignableFrom(a));
+    assertTrue(TypeToken.get(b).isAssignableFrom(b));
+
+    // listOfInteger = listOfNumber; // doesn't compile; must be false
+    assertFalse(TypeToken.get(a).isAssignableFrom(b));
+    // listOfNumber = listOfInteger; // doesn't compile; must be false
+    assertFalse(TypeToken.get(b).isAssignableFrom(a));
+  }
+
+  public void testIsAssignableFromWithBasicWildcards() throws Exception {
+    Type a = getClass().getDeclaredField("listOfString").getGenericType();
+    Type b = getClass().getDeclaredField("listOfUnknown").getGenericType();
+    assertTrue(TypeToken.get(a).isAssignableFrom(a));
+    assertTrue(TypeToken.get(b).isAssignableFrom(b));
+
+    // listOfString = listOfUnknown  // doesn't compile; must be false
+    assertFalse(TypeToken.get(a).isAssignableFrom(b));
+    listOfUnknown = listOfString; // compiles; must be true
+    assertTrue(TypeToken.get(b).isAssignableFrom(a));
+  }
+
+  public void testIsAssignableFromWithNestedWildcards() throws Exception {
+    Type a = getClass().getDeclaredField("listOfSetOfString").getGenericType();
+    Type b = getClass().getDeclaredField("listOfSetOfUnknown").getGenericType();
+    assertTrue(TypeToken.get(a).isAssignableFrom(a));
+    assertTrue(TypeToken.get(b).isAssignableFrom(b));
+
+    // listOfSetOfString = listOfSetOfUnknown; // doesn't compile; must be false
+    assertFalse(TypeToken.get(a).isAssignableFrom(b));
+    // listOfSetOfUnknown = listOfSetOfString; // doesn't compile; must be false
+    assertFalse(TypeToken.get(b).isAssignableFrom(a));
+  }
+}