Fixes #1361. Private fields promotion tests added

LanguageFeatures/Private-fields-promotion/promotion_A01_t01.dart

@@ -0,0 +1,34 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable if all of the
+/// conditions above are met
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class C {
+  final int? _x;
+  final int? _y = 42;
+  C(this._x);
+
+  void test() {
+    if (_x != null) {
+      _x.isOdd;
+    }
+    if (_y != null) {
+      _y.isOdd;
+    }
+  }
+}
+
+main() {
+  C(42).test();
+}

LanguageFeatures/Private-fields-promotion/promotion_A01_t02.dart

@@ -0,0 +1,30 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable if all of the
+/// conditions above are met. Test type variable
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class C<T> {
+  final T _x;
+  C(this._x);
+
+  void test() {
+    if (_x is int) {
+      _x.isOdd;
+    }
+  }
+}
+
+main() {
+  C(42).test();
+}

LanguageFeatures/Private-fields-promotion/promotion_A01_t03.dart

@@ -0,0 +1,35 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable if all of the
+/// conditions above are met. Test type variable
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class A {}
+class B extends A {
+  void foo() {}
+}
+
+class C<T extends A> {
+  final T _x;
+  C(this._x);
+
+  void test() {
+    if (_x is B) {
+      _x.foo();
+    }
+  }
+}
+
+main() {
+  C(B()).test();
+}

LanguageFeatures/Private-fields-promotion/promotion_A01_t04.dart

@@ -0,0 +1,59 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable if all of the
+/// conditions above are met. Test the case when there are other concrete
+/// instance getters with the same name in the same library and they are also
+/// final fields
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class A {
+  final int? _x;
+  A(this._x);
+
+  void testA() {
+    if (_x != null) {
+      _x.isOdd;
+    }
+  }
+}
+
+class B {
+  final String? _x;
+  B(this._x);
+
+  void testB() {
+    if (_x != null) {
+      _x.substring(0);
+    }
+  }
+}
+
+class C extends A {
+  final int? _x;
+  C(this._x) : super(_x);
+
+  void testC() {
+    if (_x != null) {
+      _x.isOdd;
+    }
+    if (super._x != null) {
+      super._x.isOdd;
+    }
+  }
+}
+
+main() {
+  A(42).testA();
+  B("X").testB();
+  C(1).testC();
+}

LanguageFeatures/Private-fields-promotion/promotion_A01_t05.dart

@@ -0,0 +1,63 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable if all of the
+/// conditions above are met. Test that the right variable is promoted
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class A {
+  final int? _x;
+  A(this._x);
+}
+
+class C extends A {
+  final int? _x;
+  C(this._x) : super(_x);
+
+  void testC() {
+    if (_x != null) {
+      super._x.isOdd;
+//             ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+    if (super._x != null) {
+      _x.isOdd;
+//       ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+  }
+}
+
+mixin M on A {
+  final int? _x = 0;
+
+  void testM() {
+    if (_x != null) {
+      super._x.isOdd;
+//             ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+    if (super._x != null) {
+      _x.isOdd;
+//       ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+  }
+}
+
+main() {
+  C(42).testC();
+}

LanguageFeatures/Private-fields-promotion/promotion_A02_t01.dart

@@ -0,0 +1,27 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable even if it is late
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class C {
+  late final int? _x;
+
+  void test() {
+    _x = 42;
+    _x.isOdd;
+  }
+}
+
+main() {
+  C().test();
+}

LanguageFeatures/Private-fields-promotion/promotion_A02_t02.dart

@@ -0,0 +1,31 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is promotable even if it is late
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class A {
+  void foo() {}
+}
+
+class C<T extends A> {
+  late final T? _x;
+
+  void test(T t) {
+    _x = t;
+    _x.foo();
+  }
+}
+
+main() {
+  C().test(A());
+}

LanguageFeatures/Private-fields-promotion/promotion_A03_t01.dart

@@ -0,0 +1,40 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is not promotable if it is not
+/// private
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class C {
+  final int? x;
+  final int? y = 42;
+  C(this.x);
+
+  void test() {
+    if (x != null) {
+      x.isOdd;
+//      ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+    if (y != null) {
+      y.isOdd;
+//      ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+  }
+}
+
+main() {
+  C(42).test();
+}

LanguageFeatures/Private-fields-promotion/promotion_A03_t02.dart

@@ -0,0 +1,33 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion An instance field is promotable only if
+/// (a) it is private,
+/// (b) it is final, and
+/// (c) all other concrete instance getters with the same name in the same
+/// library are also final fields
+///
+/// @description Checks that an instance field is not promotable if it is not
+/// private. Test type variable
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+class C<T> {
+  final T x;
+  C(this.x);
+
+  void test() {
+    if (x is int) {
+      x.isOdd;
+//      ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+    }
+  }
+}
+
+main() {
+  C(42).test();
+}