What is the bug?
While working on greensopinion/flutter-vector-map-tiles#149 i discovered that the current CustomPoint implementation lead to a cast exception at runtime.
This behaviour is documented in the parent class math.Point but isn't mentioned in CustomPoint:
/// Important Note: This function accepts a num as its argument only so
/// that you can scale Point<double> objects by an int factor. Because the
/// * operator always returns the same type of Point as it is called on,
/// passing in a double [factor] on a Point<int> causes a
/// runtime error.
How can we reproduce it?
final pDouble = CustomPoint<double>(1, 2);
final pInt = CustomPoint<int>(3,4);
var point;
point = pInt + pDouble; // runtime exception
point = pInt + pDouble; // runtime exception
point = pInt * pDouble; // runtime exception
point = pInt / pDouble; // runtime exception
Potentially this would throw an exception too:
point = CustomPoint<int, int>(5, 5) / CustomPoint<int, int>(2, 2); // runtime exception
Do you have a potential solution?
The issue is that other may be a num or double and turns the result into a double while the function casts it to an int.
For example here:
/// Create new [CustomPoint] where [x] and [y] values are added to [other]
/// point [x] and [y] values
@override
CustomPoint<T> operator +(math.Point other) {
return CustomPoint<T>((x + other.x) as T, (y + other.y) as T);
}Possible solutions:
- Add documentation to the dangerous functions like it's done in math.Point. This could lead to potential errors for users but might not be that problematic since CustomPoint is mostly used internally or by plugin developers.
- force
other to be the same type as the CustomPoint instance. This requires transforming every working double/int compination to be converted to a double/double.
- Use named functions like:
CustomPoint<T> multiplyWithInt(CustomPoint<int> other) {} // int/int, double/int
CustomPoint<double> multiplyWithDouble(CustomPoint<double> other) {} // double/double, int/doublePlatforms
tested on android but should
Severity
Erroneous: Prevents normal functioning and causes errors in the console
What is the bug?
While working on greensopinion/flutter-vector-map-tiles#149 i discovered that the current CustomPoint implementation lead to a cast exception at runtime.
This behaviour is documented in the parent class math.Point but isn't mentioned in CustomPoint:
How can we reproduce it?
Potentially this would throw an exception too:
Do you have a potential solution?
The issue is that
othermay be a num or double and turns the result into a double while the function casts it to an int.For example here:
Possible solutions:
otherto be the same type as the CustomPoint instance. This requires transforming every working double/int compination to be converted to a double/double.Platforms
tested on android but should
Severity
Erroneous: Prevents normal functioning and causes errors in the console