Added a few unit tests.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1209119 13f79535-47bb-0310-9956-ffa450edef68

src/test/java/org/apache/commons/math/fraction/FractionFormatTest.java

@@ -136,6 +136,44 @@ public class FractionFormatTest {
         }
     }
 
+    @Test
+    public void testParseOne1() {
+        String source = "1 / 1";
+        Fraction c = properFormat.parse(source);
+        Assert.assertNotNull(c);
+        Assert.assertEquals(1, c.getNumerator());
+        Assert.assertEquals(1, c.getDenominator());
+    }
+
+    @Test
+    public void testParseOne2() {
+        String source = "10 / 10";
+        Fraction c = properFormat.parse(source);
+        Assert.assertNotNull(c);
+        Assert.assertEquals(1, c.getNumerator());
+        Assert.assertEquals(1, c.getDenominator());
+    }
+
+    @Test
+    public void testParseZero1() {
+        String source = "0 / 1";
+        Fraction c = properFormat.parse(source);
+        Assert.assertNotNull(c);
+        Assert.assertEquals(0, c.getNumerator());
+        Assert.assertEquals(1, c.getDenominator());
+    }
+
+    @Test
+    public void testParseZero2() {
+        String source = "-0 / 1";
+        Fraction c = properFormat.parse(source);
+        Assert.assertNotNull(c);
+        Assert.assertEquals(0, c.getNumerator());
+        Assert.assertEquals(1, c.getDenominator());
+        // This test shows that the sign is not preserved.
+        Assert.assertEquals(Double.POSITIVE_INFINITY, 1d / c.doubleValue(), 0);
+    }
+
     @Test
     public void testParseInvalid() {
         String source = "a";