tests/language/anonymous_methods/expression/cascaded_test.dart

// Copyright (c) 2026, 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.

// Anonymous methods using cascaded accesses.
// SharedOptions=--enable-experiment=anonymous-methods

import 'package:expect/expect.dart';
import '../../static_type_helper.dart';

StringBuffer buffer = StringBuffer('');
int foo = 42;

void main() {
  // No dependency on `this` or parameters.
  {
    final v1 = buffer..=> foo;
    final v2 = (buffer..=> foo)..=> foo;
    final v3 = (buffer..=> foo).=> foo;
    final v4 = (buffer.=> foo)..=> foo;
    final v5 = buffer..=> foo..=> foo;
    final v6 = buffer..=> foo.=> foo;
    final v7 = buffer.=> foo..=> foo;
    v1.expectStaticType<Exactly<StringBuffer>>;
    v2.expectStaticType<Exactly<StringBuffer>>;
    v3.expectStaticType<Exactly<int>>;
    v4.expectStaticType<Exactly<int>>;
    v5.expectStaticType<Exactly<StringBuffer>>;
    v6.expectStaticType<Exactly<StringBuffer>>;
    v7.expectStaticType<Exactly<int>>;
    Expect.equals(buffer, v1);
    Expect.equals(buffer, v2);
    Expect.equals(foo, v3);
    Expect.equals(foo, v4);
    Expect.equals(buffer, v5);
    Expect.equals(buffer, v6);
    Expect.equals(foo, v7);
  }

  // Dependency on `this`.
  {
    final v1 = buffer..=> this.length;
    final v2 = (buffer..=> this.length)..=> this.length.isEven ? 'true' : '';
    final v3 = buffer..=> this == buffer..=> this.length;
    v1.expectStaticType<Exactly<StringBuffer>>;
    v2.expectStaticType<Exactly<StringBuffer>>;
    v3.expectStaticType<Exactly<StringBuffer>>;
    Expect.equals(buffer, v1);
    Expect.equals(buffer, v2);
    Expect.equals(buffer, v3);
  }

  // Dependency on implicit `this`.
  {
    final v1 = buffer..=> length;
    final v2 = (buffer..=> length)..=> length.isEven ? 'true' : '';
    final v3 = buffer..=> true ^ length.isEven..=> toString();
    v1.expectStaticType<Exactly<StringBuffer>>;
    v2.expectStaticType<Exactly<StringBuffer>>;
    v3.expectStaticType<Exactly<StringBuffer>>;
    Expect.equals(buffer, v1);
    Expect.equals(buffer, v2);
    Expect.equals(buffer, v3);
  }

  // Dependency on parameter.
  {
    final v1 = buffer..(p) => p.length;
    final v2 = (buffer..(p) => p == buffer)..(p) => p == buffer ? 'true' : '';
    final v3 = (buffer..(p) => p == buffer)..(q) => q == buffer ? 'true' : '';
    final v4 = buffer..(p) => p == buffer..(p) => p.length;
    final v5 = buffer..(p) => (p == buffer..(q) => p.length);
    v1.expectStaticType<Exactly<StringBuffer>>;
    v2.expectStaticType<Exactly<StringBuffer>>;
    v3.expectStaticType<Exactly<StringBuffer>>;
    v4.expectStaticType<Exactly<StringBuffer>>;
    v5.expectStaticType<Exactly<StringBuffer>>;
    Expect.equals(buffer, v1);
    Expect.equals(buffer, v2);
    Expect.equals(buffer, v3);
    Expect.equals(buffer, v4);
    Expect.equals(buffer, v5);
  }

  // Dependency on parameter with type annotation.
  {
    final v1 = buffer..(StringBuffer p) => p.length;
    final v2 = (buffer..(Object? p) => p == buffer)
        ..(StringBuffer p) => p.isEmpty ? 'true' : '';
    final v3 = (buffer..(Object p) => p == buffer)
        ..(StringBuffer q) => q.isEmpty ? 'true' : '';
    final v4 = buffer..(Object p) => p == 1..(StringBuffer p) => p.length;
    final v5 = buffer..(StringBuffer p) => (p == buffer..(q) => p.length);
    v1.expectStaticType<Exactly<StringBuffer>>;
    v2.expectStaticType<Exactly<StringBuffer>>;
    v3.expectStaticType<Exactly<StringBuffer>>;
    v4.expectStaticType<Exactly<StringBuffer>>;
    v5.expectStaticType<Exactly<StringBuffer>>;
    Expect.equals(buffer, v1);
    Expect.equals(buffer, v2);
    Expect.equals(buffer, v3);
    Expect.equals(buffer, v4);
    Expect.equals(buffer, v5);
  }
}