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Migration guide for describeEnum and EnumProperty

Summary

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The global method describeEnum has been deprecated. Previous uses of describeEnum(Enum.something) should use Enum.something.name instead.

The class EnumProperty was modified to extend <T extends Enum?> instead of <T>. Existing uses of EnumProperty<NotAnEnum> should use DiagnosticsProperty<NotAnEnum> instead.

Context

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Dart 2.17 introduced enhanced enums, which added Enum as a type. As a result, all enums got a name getter, which made describeEnum redundant. Before that, enum classes were often analyzed using an EnumProperty.

The describeEnum method was used to convert an enum value to a string, since Enum.something.toString() would produce Enum.something instead of something, which a lot of users wanted. Now, the name getter does this.

The describeEnum function is being deprecated, so the EnumProperty class is updated to only accept Enum objects.

Description of change

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Remove describeEnum.

  • Replace describeEnum(Enum.something) with Enum.something.name.

The EnumProperty now expects null or an Enum; you can no longer pass it a non-Enum class.

Migration guide

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If you previously used describeEnum(Enum.field) to access the string value from an enum, you can now call Enum.field.name.

If you previously used EnumProperty<NotAnEnum>, you can now use the generic DiagnosticsProperty<NotAnEnum>.

Code before migration:

dart
enum MyEnum { paper, rock }

print(describeEnum(MyEnum.paper)); // output: paper

// TextInputType is not an Enum
properties.add(EnumProperty<TextInputType>( ... ));

Code after migration:

dart
enum MyEnum { paper, rock }

print(MyEnum.paper.name); // output: paper

// TextInputType is not an Enum
properties.add(DiagnosticsProperty<TextInputType>( ... ));

Timeline

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Landed in version: 3.14.0-2.0.pre
In stable release: 3.16

References

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API documentation:

Relevant issues:

Relevant PRs: