[LANG-1444] NumberUtils.createNumber() does not create BigDecimal for

decimal fractions tending to zero

Author: garydgregory

src/test/java/org/apache/commons/lang3/math/NumberUtilsTest.java

@@ -1723,7 +1723,7 @@ void testStringCreateNumberEnsureNoPrecisionLoss() {
         assertInstanceOf(BigDecimal.class, NumberUtils.createNumber("0001.797693134862315759e+308"));
         assertInstanceOf(BigDecimal.class, NumberUtils.createNumber("-001.797693134862315759e+308"));
         assertInstanceOf(BigDecimal.class, NumberUtils.createNumber("+001.797693134862315759e+308"));
-        //LANG-1613
+        // LANG-1613
         assertInstanceOf(Double.class, NumberUtils.createNumber("2.2250738585072014E-308"));
         assertInstanceOf(Double.class, NumberUtils.createNumber("2.2250738585072014E-308D"));
         assertInstanceOf(Double.class, NumberUtils.createNumber("2.2250738585072014E-308F"));
@@ -1735,6 +1735,33 @@ void testStringCreateNumberEnsureNoPrecisionLoss() {
         assertInstanceOf(Double.class, NumberUtils.createNumber("1.7976931348623157E308F"));
         assertInstanceOf(Double.class, NumberUtils.createNumber("4.9e-324D"));
         assertInstanceOf(Double.class, NumberUtils.createNumber("4.9e-324F"));
+        // LANG-1444
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.1"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.01"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.0001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.00001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.0000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.00000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.0000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.00000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.000000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.0000000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.00000000000001"));
+        assertInstanceOf(Double.class, NumberUtils.createNumber("1.000000000000001"));
+        // Now we get Floats: This happens because Double.valueOf("1.000000000000001") = 1.000000000000001 and Double.valueOf("1.0000000000000001") = 1.0. In
+        // the latter case because we've lost the precision, it no longer matters whether we store the number as a Double or a Float, so we use a Float because
+        // it's been truncated.
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.0000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.00000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.000000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.0000000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.00000000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.000000000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.0000000000000000000001"));
+        assertInstanceOf(Float.class, NumberUtils.createNumber("1.00000000000000000000001"));
     }
 
     /**