Fixed FloatMath.toString(), added tests.

src/main/java/pythagoras/f/FloatMath.java

@@ -388,7 +388,11 @@ public class FloatMath
     public static String toString (float value)
     {
         StringBuilder buf = new StringBuilder();
-        buf.append(value >= 0 ? "+" : "-");
+        if (value >= 0) buf.append("+");
+        else {
+            buf.append("-");
+            value = -value;
+        }
         int ivalue = (int)value;
         buf.append(ivalue);
         if (TO_STRING_DECIMAL_PLACES > 0) {

src/test/java/pythagoras/f/FloatMathTest.java

@@ -0,0 +1,31 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import org.junit.*;
+import static org.junit.Assert.*;
+
+/**
+ * Tests parts of the {@link FloatMath} class.
+ */
+public class FloatMathTest
+{
+    @Test public void testToString () {
+        assertEquals("+1.0", FloatMath.toString(1f));
+        assertEquals("-1.0", FloatMath.toString(-1f));
+        assertEquals("+1.1", FloatMath.toString(1.1f));
+        assertEquals("-1.1", FloatMath.toString(-1.1f));
+        assertEquals("+3.141", FloatMath.toString(FloatMath.PI));
+        assertEquals("-3.141", FloatMath.toString(-FloatMath.PI));
+
+        FloatMath.setToStringDecimalPlaces(5);
+        assertEquals("+1.0", FloatMath.toString(1f));
+        assertEquals("-1.0", FloatMath.toString(-1f));
+        assertEquals("+1.1", FloatMath.toString(1.1f));
+        assertEquals("-1.1", FloatMath.toString(-1.1f));
+        assertEquals("+3.14159", FloatMath.toString(FloatMath.PI));
+        assertEquals("-3.14159", FloatMath.toString(-FloatMath.PI));
+    }
+}