diagnostic_describe_all_properties.md

Pattern: Missing public property reference in debug method

Issue: -

Description

Implementers of Diagnosticable should reference all public properties in a debugFillProperties(...) or debugDescribeChildren(...) method implementation to improve debuggability at runtime.

Public properties are defined as fields and getters that are

• not package-private (e.g., prefixed with _)
• not static or overriding
• not themselves Widgets or collections of Widgets

In addition, the "debug" prefix is treated specially for properties in Flutter. For the purposes of diagnostics, a property foo and a prefixed property debugFoo are treated as effectively describing the same property and it is sufficient to refer to one or the other.

Example of incorrect code:

class Absorber extends Widget {
 bool get absorbing => _absorbing;
 bool _absorbing;
 bool get ignoringSemantics => _ignoringSemantics;
 bool _ignoringSemantics;
 @override
 void debugFillProperties(DiagnosticPropertiesBuilder properties) {
  super.debugFillProperties(properties);
  properties.add(DiagnosticsProperty<bool>('absorbing', absorbing));
  // Missing reference to ignoringSemantics
 }
} 

Example of correct code:

class Absorber extends Widget {
 bool get absorbing => _absorbing;
 bool _absorbing;
 bool get ignoringSemantics => _ignoringSemantics;
 bool _ignoringSemantics;
 @override
 void debugFillProperties(DiagnosticPropertiesBuilder properties) {
  super.debugFillProperties(properties);
  properties.add(DiagnosticsProperty<bool>('absorbing', absorbing));
  properties.add(DiagnosticsProperty<bool>('ignoringSemantics', ignoringSemantics));
 }
} 

Further Reading

• Linter for Dart - diagnostic_describe_all_properties