Field promotion: more thorough language tests, plus a CFE bug fix.

Bug: https://github.com/dart-lang/language/issues/2020
Change-Id: I1c604b548f2635b50addc0a97b105da8391b043c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/269641
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>

pkg/front_end/lib/src/fasta/type_inference/inference_visitor_base.dart

@@ -2960,6 +2960,7 @@ abstract class InferenceVisitorBase implements InferenceVisitor {
         target.isObjectMember ||
         target.isNullableInstanceMember);
     Field field = target.member as Field;
+    Expression originalReceiver = receiver;
 
     DartType calleeType = target.getGetterType(this);
     FunctionType functionType = getFunctionTypeForImplicitCall(calleeType);
@@ -2977,11 +2978,10 @@ abstract class InferenceVisitorBase implements InferenceVisitor {
       // We won't report the error until later (after we have an
       // invocationResult), but we need to gather "why not promoted" info now,
       // before we tell flow analysis about the property get.
-      whyNotPromoted = flowAnalysis.whyNotPromoted(receiver);
+      whyNotPromoted = flowAnalysis.whyNotPromoted(originalReceiver);
     }
 
     Name originalName = field.name;
-    Expression originalReceiver = receiver;
     Member originalTarget = field;
     InstanceAccessKind kind;
     switch (target.kind) {
@@ -2998,7 +2998,7 @@ abstract class InferenceVisitorBase implements InferenceVisitor {
         throw new UnsupportedError('Unexpected target kind $target');
     }
     InstanceGet originalPropertyGet = new InstanceGet(
-        kind, originalReceiver, originalName,
+        kind, receiver, originalName,
         resultType: calleeType, interfaceTarget: originalTarget)
       ..fileOffset = fileOffset;
     calleeType = flowAnalysis.propertyGet(originalPropertyGet, originalReceiver,

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.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.
+
+// Tests a corner case of promotion with implicit `.call` hoisting.
+
+class A {
+  num call(int value) => 0;
+}
+
+class B extends A {
+  int call(num value) => 0;
+}
+
+class C {
+  final A _a;
+
+  C(this._a);
+}
+
+void test(C c, num n) {
+  if (c._a is B) {
+    // Since the call has arguments, it is subject to hoisting by the front end.
+    // We need to verify that the hoisting process properly passes the original
+    // receiver (`c._a`) to flow analysis so that the promotion information is
+    // not lost.
+    c._a(n);
+  }
+}
+
+main() {}

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.dart.textual_outline.expect

@@ -0,0 +1,15 @@
+class A {
+  num call(int value) => 0;
+}
+
+class B extends A {
+  int call(num value) => 0;
+}
+
+class C {
+  final A _a;
+  C(this._a);
+}
+
+void test(C c, num n) {}
+main() {}

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.dart.textual_outline_modelled.expect

@@ -0,0 +1,15 @@
+class A {
+  num call(int value) => 0;
+}
+
+class B extends A {
+  int call(num value) => 0;
+}
+
+class C {
+  C(this._a);
+  final A _a;
+}
+
+main() {}
+void test(C c, num n) {}

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.dart.weak.expect

@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method call(core::int value) → core::num
+    return 0;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method call(core::num value) → core::int
+    return 0;
+}
+class C extends core::Object {
+  final field self::A _a;
+  constructor •(self::A _a) → self::C
+    : self::C::_a = _a, super core::Object::•()
+    ;
+}
+static method test(self::C c, core::num n) → void {
+  if(c.{self::C::_a}{self::A} is{ForNonNullableByDefault} self::B) {
+    let final self::C #t1 = c in let final core::num #t2 = n in #t1.{self::C::_a}{self::B}.{self::B::call}(#t2){(core::num) → core::int};
+  }
+}
+static method main() → dynamic {}

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.dart.weak.modular.expect

@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method call(core::int value) → core::num
+    return 0;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method call(core::num value) → core::int
+    return 0;
+}
+class C extends core::Object {
+  final field self::A _a;
+  constructor •(self::A _a) → self::C
+    : self::C::_a = _a, super core::Object::•()
+    ;
+}
+static method test(self::C c, core::num n) → void {
+  if(c.{self::C::_a}{self::A} is{ForNonNullableByDefault} self::B) {
+    let final self::C #t1 = c in let final core::num #t2 = n in #t1.{self::C::_a}{self::B}.{self::B::call}(#t2){(core::num) → core::int};
+  }
+}
+static method main() → dynamic {}

pkg/front_end/testcases/inference_update_2/call_invocation_with_hoisting.dart.weak.outline.expect

@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    ;
+  method call(core::int value) → core::num
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    ;
+  method call(core::num value) → core::int
+    ;
+}
+class C extends core::Object {
+  final field self::A _a;
+  constructor •(self::A _a) → self::C
+    ;
+}
+static method test(self::C c, core::num n) → void
+  ;
+static method main() → dynamic
+  ;

pkg/front_end/testcases/modular.status

@@ -64,6 +64,7 @@ inference/mixin_inference_unification_2: TypeCheckError
 inference_new/infer_assign_to_index_super_upwards: TypeCheckError
 inference_new/infer_assign_to_index_this_upwards: TypeCheckError
 inference_new/infer_assign_to_index_upwards: TypeCheckError
+inference_update_2/call_invocation_with_hoisting: TypeCheckError
 late_lowering/covariant_late_field: TypeCheckError
 nnbd/covariant_late_field: TypeCheckError
 nnbd/getter_vs_setter_type: TypeCheckError

pkg/front_end/testcases/weak.status

@@ -206,6 +206,7 @@ inference/override_equals: RuntimeError
 inference_new/infer_assign_to_index_super_upwards: TypeCheckError
 inference_new/infer_assign_to_index_this_upwards: TypeCheckError
 inference_new/infer_assign_to_index_upwards: TypeCheckError
+inference_update_2/call_invocation_with_hoisting: TypeCheckError
 late_lowering/covariant_late_field: TypeCheckError
 nnbd/covariant_late_field: TypeCheckError
 nnbd/getter_vs_setter_type: TypeCheckError

tests/language/inference_update_2/promotion_makes_new_extension_available_test.dart

@@ -0,0 +1,158 @@
+// 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.
+
+// Tests that promotion of a field makes it possible to access methods, getters,
+// and operators in an extension that doesn't apply to the unpromoted type.
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+import '../static_type_helper.dart';
+
+class A {}
+
+class B extends A {
+  final int Function(int) field;
+
+  B(this.field);
+}
+
+extension on B {
+  int Function(int) get getter => field;
+  int method(int value) => 0;
+  int call(int value) => 0;
+  int operator [](int index) => 0;
+  operator []=(int index, int value) {}
+  int operator +(int other) => 0;
+}
+
+class C {
+  final A _a;
+
+  C(this._a);
+
+  void testThisAccess() {
+    if (_a is B) {
+      _a.field.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.getter.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.method.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+        ..expectStaticType<Exactly<int>>();
+      (_a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+class D extends C {
+  D(super._a);
+
+  void testSuperAccess() {
+    if (super._a is B) {
+      super._a.field.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.getter.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.method.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      super._a[contextType(0)..expectStaticType<Exactly<int>>()] =
+          contextType(0)..expectStaticType<Exactly<int>>();
+      (super._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+void testPrefixedIdentifier(C c) {
+  if (c._a is B) {
+    c._a.field.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.method.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    (c._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+void testGeneralPropertyAccess(C c) {
+  // The analyzer uses a special data structure for `IDENTIFIER.IDENTIFIER`, so
+  // we need to test the general case of property accesses as well.
+  if ((c)._a is B) {
+    (c)._a.field.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.method.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    (c)._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    ((c)._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+main() {
+  var d = D(B((_) => 0));
+  d.testThisAccess();
+  d.testSuperAccess();
+  testPrefixedIdentifier(d);
+  testGeneralPropertyAccess(d);
+}

tests/language/inference_update_2/promotion_makes_new_extension_available_via_non_nullability_test.dart

@@ -0,0 +1,156 @@
+// 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.
+
+// Tests that promotion of a field makes it possible to access methods, getters,
+// and operators in an extension that doesn't apply to the unpromoted type.
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+import '../static_type_helper.dart';
+
+class A {
+  final int Function(int) field;
+
+  A(this.field);
+}
+
+extension on A {
+  int Function(int) get getter => field;
+  int method(int value) => 0;
+  int call(int value) => 0;
+  int operator [](int index) => 0;
+  operator []=(int index, int value) {}
+  int operator +(int other) => 0;
+}
+
+class C {
+  final A? _a;
+
+  C(this._a);
+
+  void testThisAccess() {
+    if (_a != null) {
+      _a.field.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.getter.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.method.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+        ..expectStaticType<Exactly<int>>();
+      (_a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+class D extends C {
+  D(super._a);
+
+  void testSuperAccess() {
+    if (super._a != null) {
+      super._a.field.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.getter.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.method.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      super._a[contextType(0)..expectStaticType<Exactly<int>>()] =
+          contextType(0)..expectStaticType<Exactly<int>>();
+      (super._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+void testPrefixedIdentifier(C c) {
+  if (c._a != null) {
+    c._a.field.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.method.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    (c._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+void testGeneralPropertyAccess(C c) {
+  // The analyzer uses a special data structure for `IDENTIFIER.IDENTIFIER`, so
+  // we need to test the general case of property accesses as well.
+  if ((c)._a != null) {
+    (c)._a.field.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.method.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    (c)._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    ((c)._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+main() {
+  var d = D(A((_) => 0));
+  d.testThisAccess();
+  d.testSuperAccess();
+  testPrefixedIdentifier(d);
+  testGeneralPropertyAccess(d);
+}

tests/language/inference_update_2/promotion_makes_new_interface_available_test.dart

@@ -0,0 +1,155 @@
+// 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.
+
+// Tests that promotion of a field makes it possible to access methods, getters,
+// and operators that aren't exposed from the unpromoted type.
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+import '../static_type_helper.dart';
+
+class A {}
+
+class B extends A {
+  final int Function(int) field;
+  int Function(int) get getter => field;
+  int method(int value) => 0;
+  int call(int value) => 0;
+  int operator [](int index) => 0;
+  operator []=(int index, int value) {}
+  int operator +(int other) => 0;
+
+  B(this.field);
+}
+
+class C {
+  final A _a;
+
+  C(this._a);
+
+  void testThisAccess() {
+    if (_a is B) {
+      _a.field.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.getter.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a.method.expectStaticType<Exactly<int Function(int)>>();
+      _a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+        ..expectStaticType<Exactly<int>>();
+      (_a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+class D extends C {
+  D(super._a);
+
+  void testSuperAccess() {
+    if (super._a is B) {
+      super._a.field.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .field(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.getter.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .getter(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.method.expectStaticType<Exactly<int Function(int)>>();
+      super
+          ._a
+          .method(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a(contextType(0)..expectStaticType<Exactly<int>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+          .expectStaticType<Exactly<int>>();
+      super._a[contextType(0)..expectStaticType<Exactly<int>>()] =
+          contextType(0)..expectStaticType<Exactly<int>>();
+      (super._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+void testPrefixedIdentifier(C c) {
+  if (c._a is B) {
+    c._a.field.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.method.expectStaticType<Exactly<int Function(int)>>();
+    c._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    (c._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+void testGeneralPropertyAccess(C c) {
+  // The analyzer uses a special data structure for `IDENTIFIER.IDENTIFIER`, so
+  // we need to test the general case of property accesses as well.
+  if ((c)._a is B) {
+    (c)._a.field.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .field(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.getter.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .getter(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.method.expectStaticType<Exactly<int Function(int)>>();
+    (c)
+        ._a
+        .method(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a(contextType(0)..expectStaticType<Exactly<int>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a[contextType(0)..expectStaticType<Exactly<int>>()]
+        .expectStaticType<Exactly<int>>();
+    (c)._a[contextType(0)..expectStaticType<Exactly<int>>()] = contextType(0)
+      ..expectStaticType<Exactly<int>>();
+    ((c)._a + (contextType(0)..expectStaticType<Exactly<int>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+main() {
+  var d = D(B((_) => 0));
+  d.testThisAccess();
+  d.testSuperAccess();
+  testPrefixedIdentifier(d);
+  testGeneralPropertyAccess(d);
+}

tests/language/inference_update_2/promotion_narrows_interface_test.dart

@@ -0,0 +1,141 @@
+// 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.
+
+// Tests that promotion of a field narrows the types of methods, getters,
+// and operators that are also exposed from the unpromoted type.
+
+// SharedOptions=--enable-experiment=inference-update-2
+
+import '../static_type_helper.dart';
+
+class A {
+  Object get getter => 0;
+  num method(int value) => 0;
+  num call(int value) => 0;
+  num operator [](int index) => 0;
+  operator []=(int index, int value) {}
+  num operator +(int other) => 0;
+}
+
+class B extends A {
+  int Function(num) get getter => (_) => 0;
+  int method(num value) => 0;
+  int call(num value) => 0;
+  int operator [](num index) => 0;
+  operator []=(num index, num value) {}
+  int operator +(num other) => 0;
+}
+
+class C {
+  final A _a;
+
+  C(this._a);
+
+  void testThisAccess() {
+    if (_a is B) {
+      _a.getter.expectStaticType<Exactly<int Function(num)>>();
+      _a
+          .getter(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      _a.method.expectStaticType<Exactly<int Function(num)>>();
+      _a
+          .method(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      _a(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<num>>()]
+          .expectStaticType<Exactly<int>>();
+      _a[contextType(0)..expectStaticType<Exactly<num>>()] = contextType(0)
+        ..expectStaticType<Exactly<num>>();
+      (_a + (contextType(0)..expectStaticType<Exactly<num>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+class D extends C {
+  D(super._a);
+
+  void testSuperAccess() {
+    if (super._a is B) {
+      super._a.getter.expectStaticType<Exactly<int Function(num)>>();
+      super
+          ._a
+          .getter(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      super._a.method.expectStaticType<Exactly<int Function(num)>>();
+      super
+          ._a
+          .method(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a(contextType(0)..expectStaticType<Exactly<num>>())
+          .expectStaticType<Exactly<int>>();
+      super
+          ._a[contextType(0)..expectStaticType<Exactly<num>>()]
+          .expectStaticType<Exactly<int>>();
+      super._a[contextType(0)..expectStaticType<Exactly<num>>()] =
+          contextType(0)..expectStaticType<Exactly<num>>();
+      (super._a + (contextType(0)..expectStaticType<Exactly<num>>()))
+          .expectStaticType<Exactly<int>>();
+    }
+  }
+}
+
+void testPrefixedIdentifier(C c) {
+  if (c._a is B) {
+    c._a.getter.expectStaticType<Exactly<int Function(num)>>();
+    c._a
+        .getter(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    c._a.method.expectStaticType<Exactly<int Function(num)>>();
+    c._a
+        .method(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    c
+        ._a(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<num>>()]
+        .expectStaticType<Exactly<int>>();
+    c._a[contextType(0)..expectStaticType<Exactly<num>>()] = contextType(0)
+      ..expectStaticType<Exactly<num>>();
+    (c._a + (contextType(0)..expectStaticType<Exactly<num>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+void testGeneralPropertyAccess(C c) {
+  // The analyzer uses a special data structure for `IDENTIFIER.IDENTIFIER`, so
+  // we need to test the general case of property accesses as well.
+  if ((c)._a is B) {
+    (c)._a.getter.expectStaticType<Exactly<int Function(num)>>();
+    (c)
+        ._a
+        .getter(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    (c)._a.method.expectStaticType<Exactly<int Function(num)>>();
+    (c)
+        ._a
+        .method(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a(contextType(0)..expectStaticType<Exactly<num>>())
+        .expectStaticType<Exactly<int>>();
+    (c)
+        ._a[contextType(0)..expectStaticType<Exactly<num>>()]
+        .expectStaticType<Exactly<int>>();
+    (c)._a[contextType(0)..expectStaticType<Exactly<num>>()] = contextType(0)
+      ..expectStaticType<Exactly<num>>();
+    ((c)._a + (contextType(0)..expectStaticType<Exactly<num>>()))
+        .expectStaticType<Exactly<int>>();
+  }
+}
+
+main() {
+  var d = D(B());
+  d.testThisAccess();
+  d.testSuperAccess();
+  testPrefixedIdentifier(d);
+  testGeneralPropertyAccess(d);
+}