Add integer case to double constructor test cases.
diff --git a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/CommonTestCases.java b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/CommonTestCases.java
index b0f703f..59bd68e 100644
--- a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/CommonTestCases.java
+++ b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/CommonTestCases.java
@@ -198,6 +198,7 @@
         testCases.add(new DoubleToFractionTestCase(0.00000000000001, 0, 1));
         testCases.add(new DoubleToFractionTestCase(0.40000000000001, 2, 5));
         testCases.add(new DoubleToFractionTestCase(15.0000000000001, 15, 1));
+        testCases.add(new DoubleToFractionTestCase(15.0, 15, 1));
         testCases.add(new DoubleToFractionTestCase(0.0, 0, 1));
         testCases.add(new DoubleToFractionTestCase(-0.0, 0, 1));