Upgrade question : moving optional named parameters into non optional with defaults values make migration difficult

[evaisse]

Hello,

I'm upgrading fl_chart form 0.55 to 0.69, I have a question regarding the port of optional named parameters into non optional with defaults values classes.

  const FlChartStuff({
  	// v0.55
    double? argInV55, // with default value to 22 applied later in the constructor signature
    // v0.66
    double argInV66 = 22,
  });

This does maybe not look like a big change but it does present a lot of new constrains...

For example in SideTitles, before the signature was this one :

  const SideTitles({
    // ...
    double? reservedSize, // with default value to 22
    // ...
  });

Now it's that version :

  const SideTitles({
    // ...
    double reservedSize = 22,
    // ...
  });

Before, the signature allowed us to pass null params and then it was very handy to create a new instance from wrapped configuration in widgets, e.g.

SideTitles(
  // ...
  reservedSize: widget.chartConfig?.size
  // ...
)

but now I only see 2 solutions to achieve the same behavior, but both seems ugly

The first one imply to call different constructor regarding the input value

final size = widget.chartConfig?.size;

if (size != null) {
  return SideTitles(
    // ... other params
    reservedSize: size
  	// ...
	);
} else {
	return SideTitles(
    // ... other params
	);
}

And the other one implied to pass the default lib value in my code...

SideTitles(
  // ...
  reservedSize: widget.chartConfig?.size ?? 22
  // ...
)

How will you deal with that kind of situation with the new version ?

Thx,