dart-sdk/tests/language/extension_type/field_promotion_representation_nullable_test.dart

// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// Tests that the representation variable may undergo field promotion, assuming
// that it's private.
//
// These tests specifically exercise extension types whose representation type
// is nullable, since those are handled differently by the front end than
// extension types whose representation type is non-nullable.

import '../static_type_helper.dart';

extension type E(Object Function()? _f) {
  testImplicitThisAccess() {
    if (_f != null) {
      _f.expectStaticType<Exactly<Object Function()>>();
      _f().expectStaticType<Exactly<Object>>();
    }
  }

  testExplicitThisAccess() {
    if (this._f != null) {
      this._f.expectStaticType<Exactly<Object Function()>>();
      this._f().expectStaticType<Exactly<Object>>();
    }
  }
}

testGeneralPropertyAccess(E e) {
  if ((e)._f != null) {
    (e)._f.expectStaticType<Exactly<Object Function()>>();
    (e)._f().expectStaticType<Exactly<Object>>();
  }
}

testPrefixedIdentifierAccess(E e) {
  // Note: the analyzer has a special representation for property accesses of
  // the form `IDENTIFIER.IDENTIFIER`, so we test this form separately.
  if (e._f != null) {
    e._f.expectStaticType<Exactly<Object Function()>>();
    e._f().expectStaticType<Exactly<Object>>();
  }
}

main() {
  int Function() f = () => 0;
  E(f).testImplicitThisAccess();
  E(f).testExplicitThisAccess();
  testGeneralPropertyAccess(E(f));
  testPrefixedIdentifierAccess(E(f));
}