[record_use] Completeness: record consts (record record consts)

import 'package:meta/meta.dart' show RecordUse;

void main() {
   // Records are valid keys in a constant map in Dart.
   print(SomeClass.someStaticMethod(const {
     (1, 2): 'positional-record-key',
     ('id', name: 'gemini'): 'mixed-record-key',
   }));
 }

 class SomeClass {
   @RecordUse()
   static String someStaticMethod(Object? a) => a.runtimeType.toString();
 }

(Side note we need to report them as unsupported in the meantime #2899)

package:record_use
implement in the Dart SDK
tests in the Dart SDK

✦ In Kernel (the Dart intermediate representation used by the VM and CFE), record constants are represented by the RecordConstant class:

Location: pkg/kernel/lib/src/ast/constants.dart
Structure:
- positional: A List for the positional fields.
- named: A Map<String, Constant> for the named fields, where keys are field names. The names are sorted lexicographically.
- recordType: A RecordType object describing the runtime type of the record.

In dart2js, record constants are represented by the RecordConstantValue class:

Location: pkg/compiler/lib/src/constants/values.dart
Structure:
- shape: A RecordShape object that defines the record's structure (the number of positional fields and the names of the named fields).
- values: A single List containing all field values. Positional fields come first, followed by named fields in the order specified by the
  shape.
Accessing fields: You use the shape to determine which indices in the values list correspond to which fields.

We don't have a way to represent types in the recorded uses, so we'll not record the type, but we will record positional and named fields.

[record_use] Constant Record Values (#3137)

[record_use] Record record constants

Squashed commit of the following:

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[record_use] Completeness: record consts (record record consts) #3054

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[record_use] Completeness: record consts (record record consts) #3054

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dcharkes commented on Feb 23, 2026

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