ConvertError: add back default, new constructor with message

[Bromeon]

Fixes #643.

There are unrelated CI errors we'd need to investigate, as upstream changed:

  mismatch in property export_packedbytearray, 
  GDScript: "{ "name": "export_packedbytearray", "class_name": &"", "type": 29, "hint": 23, "hint_string": "2:int", "usage": 4102 }"
    , Rust: "{ "name": "export_packedbytearray", "class_name": &"", "type": 29, "hint": 0, "hint_string": "PackedByteArray", "usage": 4102 }"
  mismatch in property export_packedint32array, 
  GDScript: "{ "name": "export_packedint32array", "class_name": &"", "type": 30, "hint": 23, "hint_string": "2:int", "usage": 4102 }"
    , Rust: "{ "name": "export_packedint32array", "class_name": &"", "type": 30, "hint": 0, "hint_string": "PackedInt32Array", "usage": 4102 }"
  mismatch in property export_packedint64array, 
  GDScript: "{ "name": "export_packedint64array", "class_name": &"", "type": 31, "hint": 23, "hint_string": "2:int", "usage": 4102 }"
    , Rust: "{ "name": "export_packedint64array", "class_name": &"", "type": 31, "hint": 0, "hint_string": "PackedInt64Array", "usage": 4102 }"
  mismatch in property export_packedfloat32array, 
  GDScript: "{ "name": "export_packedfloat32array", "class_name": &"", "type": 32, "hint": 23, "hint_string": "3:float", "usage": 4102 }"
    , Rust: "{ "name": "export_packedfloat32array", "class_name": &"", "type": 32, "hint": 0, "hint_string": "PackedFloat32Array", "usage": 4102 }"
  mismatch in property export_packedfloat64array, 
  GDScript: "{ "name": "export_packedfloat64array", "class_name": &"", "type": 33, "hint": 23, "hint_string": "3:float", "usage": 4102 }"
    , Rust: "{ "name": "export_packedfloat64array", "class_name": &"", "type": 33, "hint": 0, "hint_string": "PackedFloat64Array", "usage": 4102 }"
  mismatch in property export_packedstringarray, 
  GDScript: "{ "name": "export_packedstringarray", "class_name": &"", "type": 34, "hint": 23, "hint_string": "4:String", "usage": 4102 }"
    , Rust: "{ "name": "export_packedstringarray", "class_name": &"", "type": 34, "hint": 0, "hint_string": "PackedStringArray", "usage": 4102 }"
  mismatch in property export_packedvector2array, 
  GDScript: "{ "name": "export_packedvector2array", "class_name": &"", "type": 35, "hint": 23, "hint_string": "5:Vector2", "usage": 4102 }"
    , Rust: "{ "name": "export_packedvector2array", "class_name": &"", "type": 35, "hint": 0, "hint_string": "PackedVector2Array", "usage": 4102 }"
  mismatch in property export_packedvector3array, 
  GDScript: "{ "name": "export_packedvector3array", "class_name": &"", "type": 36, "hint": 23, "hint_string": "9:Vector3", "usage": 4102 }"
    , Rust: "{ "name": "export_packedvector3array", "class_name": &"", "type": 36, "hint": 0, "hint_string": "PackedVector3Array", "usage": 4102 }"
  mismatch in property export_packedcolorarray, 
  GDScript: "{ "name": "export_packedcolorarray", "class_name": &"", "type": 37, "hint": 23, "hint_string": "20:Color", "usage": 4102 }"
    , Rust: "{ "name": "export_packedcolorarray", "class_name": &"", "type": 37, "hint": 0, "hint_string": "PackedColorArray", "usage": 4102 }"

[GodotRust]

API docs are being generated and will be shortly available at: https://godot-rust.github.io/docs/gdext/pr-645

[lilizoey]

i fixed the unrelated ci errors in #625 actually, possibly worth just separating out into its own small PR.

just adding a manual export impl to the packed arrays like:

impl $crate::property::Export for $PackedArray {
            fn default_export_info() -> $crate::property::PropertyHintInfo {
                if sys::GdextBuild::since_api("4.3") {
                    // In 4.3 Godot can (and does) use type hint strings for packed arrays.
                    // https://github.com/godotengine/godot/pull/82952
                    $crate::property::PropertyHintInfo {
                        hint: $crate::engine::global::PropertyHint::TYPE_STRING,
                        hint_string: <$Element as $crate::property::TypeStringHint>::type_string().into(),
                    }
                } else {
                    $crate::property::PropertyHintInfo::with_hint_none(<$PackedArray as $crate::builtin::meta::GodotType>::godot_type_name())
                }

(and removing the auto-generated export impl in property.rs by passing no_export to the macro)

[Bromeon]

Oh, great to hear! Yep, would probably be good to merge the fix before the entire #625 👍

I can either cherry pick one of your commits, or you can push a commit to this PR, or open your own separate PR -- whatever works best for you.

[lilizoey]

I can make a new PR in a little bit, i dont think it'd be super easy to cherry pick out a commit so ill just probably manually copy paste it out. it's a fairly minor chsnge overall.

[lilizoey]

fixed in #646