tests for boxComplete and draw functions

src/test/java/dotsandboxes/DotsAndBoxesGridTest.java

@@ -28,4 +28,34 @@ public class DotsAndBoxesGridTest {
     }
 
     // FIXME: You need to write tests for the two known bugs in the code.
+    @Test
+    public void testDrawHorizontalThrows() {
+        DotsAndBoxesGrid grid = new DotsAndBoxesGrid(2, 2, 2);
+        grid.drawHorizontal(0,0, 1);
+        assertThrows(Exception.class, () -> {
+            grid.drawHorizontal(0,0, 1);
+        });
+    }
+    @Test
+    public void testDrawVerticalThrows() {
+        DotsAndBoxesGrid grid = new DotsAndBoxesGrid(2, 2, 2);
+        grid.drawVertical(0,0, 1);
+        assertThrows(Exception.class, () -> {
+            grid.drawVertical(0,0, 1);
+        });
+    }
+
+    @Test
+    public void testBoxComplete () {
+        DotsAndBoxesGrid grid = new DotsAndBoxesGrid(2, 2, 2);
+        grid.drawVertical(0, 0, 1);
+        assertFalse(grid.boxComplete(0, 0));
+        grid.drawVertical(1, 0, 1);
+        assertFalse(grid.boxComplete(1, 0));
+        grid.drawHorizontal(0, 0, 1);
+        assertFalse(grid.boxComplete(0, 0));
+        grid.drawHorizontal(0, 1, 1);
+        assertTrue(grid.boxComplete(0, 1));
+
+    }
 }