Added test for hasNext on JsonStreamParser.

gson/src/test/java/com/google/gson/JsonStreamParserTest.java

@@ -22,30 +22,48 @@ import java.util.NoSuchElementException;
 
 /**
  * Unit tests for {@link JsonStreamParser}
- *
+ * 
  * @author Inderjeet Singh
  */
 public class JsonStreamParserTest extends TestCase {
+  private JsonStreamParser parser;
   
+  @Override
+  protected void setUp() throws Exception {
+    super.setUp();
+    parser = new JsonStreamParser("'one' 'two'");
+  }
+
   public void testParseTwoStrings() {
-    JsonStreamParser parser = new JsonStreamParser("'one' 'two'");
     String actualOne = parser.next().getAsString();
     assertEquals("one", actualOne);
     String actualTwo = parser.next().getAsString();
     assertEquals("two", actualTwo);
   }
-  
+
   public void testIterator() {
-    Iterator<JsonElement> parser = new JsonStreamParser("'one' 'two'");
     assertTrue(parser.hasNext());
     assertEquals("one", parser.next().getAsString());
     assertTrue(parser.hasNext());
     assertEquals("two", parser.next().getAsString());
     assertFalse(parser.hasNext());
   }
-  
+
+  public void testNoSideEffectForHasNext() throws Exception {
+    assertTrue(parser.hasNext());
+    assertTrue(parser.hasNext());
+    assertTrue(parser.hasNext());
+    assertEquals("one", parser.next().getAsString());
+    
+    assertTrue(parser.hasNext());
+    assertTrue(parser.hasNext());
+    assertEquals("two", parser.next().getAsString());
+    
+    assertFalse(parser.hasNext());
+    assertFalse(parser.hasNext());
+  }
+
   public void testCallingNextBeyondAvailableInput() {
-    Iterator<JsonElement> parser = new JsonStreamParser("'one' 'two'");
     parser.next();
     parser.next();
     try {