// Examples of well documented but probably unexpected behavior in java / with 32-bit float to 64-bit float conversion.
assertFalse("Document unexpected behaviour with explicit type-casting float as double!", (double)0.2f == 0.2d );
assertFalse("Document unexpected behaviour with implicit type-cast!", 0.2f == 0.2d );
Doubled1 = newDouble( 1.1f );
Doubled2 = newDouble( "1.1f" );
assertFalse( "Document implicit type cast from float to double before calling Double(double d) constructor", d1.equals( d2 ) );
assertTrue( "Correctly converting float to double via base10 (string) representation!", newDouble( 3.1d ).equals( newDouble( newFloat( 3.1f ).toString() ) ) );
// Pinpointing the not so obvious "buggy" conversion from float to double in JSONObject
JSONObjectjo = newJSONObject();
jo.put( "bug", 3.1f ); // will call put( String key, double value ) with implicit and "buggy" type-cast from float to double
assertFalse( "The java-compiler did add some zero bits for you to the mantissa (unexpected, but well documented)", jo.get( "bug" ).equals( newDouble( 3.1d ) ) );
JSONObjectinc = newJSONObject();
inc.put( "bug", newFloat( 3.1f ) ); // This will put in instance of Float into JSONObject, i.e. call put( String key, Object value )
assertTrue( "Everything is ok here!", inc.get( "bug" ) instanceofFloat );
inc.increment( "bug" ); // after adding 1, increment will call put( String key, double value ) with implicit and "buggy" type-cast from float to double!
// this.put(key, (Float) value + 1);
// 1. The (Object)value will be typecasted to (Float)value since it is an instanceof Float actually nothing is done.
// 2. Float instance will be autoboxed into float because the + operator will work on primitives not Objects!
// 3. A float+float operation will be performed and results into a float primitive.
// 4. There is no method that matches the signature put( String key, float value), java-compiler will choose the method
// put( String key, double value) and does an implicit type-cast(!) by appending zero-bits to the mantissa