Update iterator capabilities

2 files changed, 48 insertions, 1 deletions

diff --git a/src/test/java/bjc/data/MarkListIteratorTest.java b/src/test/java/bjc/data/MarkListIteratorTest.java
new file mode 100644
index 0000000..6eb4994
--- /dev/null
+++ b/src/test/java/bjc/data/MarkListIteratorTest.java
@@ -0,0 +1,41 @@
+package bjc.data;
+
+import static org.junit.Assert.*;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+
+import bjc.test.TestUtils;
+
+/**
+ * Tests for {@link MarkListIterator}
+ * @author bjcul
+ *
+ */
+@SuppressWarnings("javadoc")
+public class MarkListIteratorTest {
+
+	@Test
+	public void test() {
+		List<String> list1 = Arrays.asList("a", "b", "c");
+		
+		MarkListIterator<String> itr1 = new MarkListIterator<>(list1);
+		itr1.mark();
+		
+		assertFalse(itr1.hasPrevious());
+		assertTrue(itr1.hasNext());
+		TestUtils.assertIteratorEquals(itr1, "a", "b", "c");
+		
+		assertTrue(itr1.hasPrevious());
+		assertFalse(itr1.hasNext());
+		
+		itr1.rollback(false);
+		
+		assertFalse(itr1.hasPrevious());
+		assertTrue(itr1.hasNext());
+		TestUtils.assertIteratorEquals(itr1, "a", "b", "c");
+	}
+
+}
diff --git a/src/test/java/bjc/test/TestUtils.java b/src/test/java/bjc/test/TestUtils.java
index d79157d..04cdf70 100644
--- a/src/test/java/bjc/test/TestUtils.java
+++ b/src/test/java/bjc/test/TestUtils.java
@@ -21,7 +21,13 @@ public class TestUtils {
 	public static <T> void assertIteratorEquals(Iterator<T> src, T... vals) {
 		for (int i = 0; i < vals.length; i++) {
 			if (src.hasNext()) {
-				assertEquals(vals[i], src.next());
+				T actNext = src.next();
+				T expNext = vals[i];
+				
+				String fmt = "mismatch at index %d";
+				String msg = String.format(fmt, i);
+				
+				assertEquals(msg, expNext, actNext);
 			} else {
 				String msg = String.format("not enough values: got %d, wanted %d", i,
 						vals.length);