[cfe] Correctly resolve extension properties in face of getter/setter conflict

Change-Id: I0b818edb27de1b2cd1dcd2e046f42616cd7cb257
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117729
Reviewed-by: Jens Johansen <jensj@google.com>

pkg/front_end/lib/src/fasta/builder/library_builder.dart

@@ -103,6 +103,9 @@ abstract class LibraryBuilder extends ModifierBuilder {
   /// Returns the [Library] built by this builder.
   Library get library;
 
+  /// Returns the import uri for the library.
+  ///
+  /// This is the canonical uri for the library, for instance 'dart:core'.
   Uri get uri;
 
   Iterator<Builder> get iterator {

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

@@ -717,13 +717,23 @@ abstract class TypeInferrerImpl extends TypeInferrer {
     }
 
     if (target.isUnresolved && includeExtensionMethods) {
+      Member otherMember =
+          _getInterfaceMember(classNode, name, !setter, fileOffset);
+      if (otherMember != null) {
+        // If we're looking for `foo` and `foo=` can be found or vice-versa then
+        // extension methods should not be found.
+        return target;
+      }
+
       ExtensionAccessCandidate bestSoFar;
       List<ExtensionAccessCandidate> noneMoreSpecific = [];
       library.scope.forEachExtension((ExtensionBuilder extensionBuilder) {
-        MemberBuilder memberBuilder =
-            extensionBuilder.lookupLocalMember(name.name, setter: setter);
-        if (memberBuilder != null && !memberBuilder.isStatic) {
-          Extension extension = extensionBuilder.extension;
+        MemberBuilder getterBuilder =
+            extensionBuilder.lookupLocalMember(name.name, setter: false);
+        MemberBuilder setterBuilder =
+            extensionBuilder.lookupLocalMember(name.name, setter: true);
+        if ((getterBuilder != null && !getterBuilder.isStatic) ||
+            (setterBuilder != null && !setterBuilder.isStatic)) {
           DartType onType;
           DartType onTypeInstantiateToBounds;
           List<DartType> inferredTypeArguments;
@@ -762,15 +772,20 @@ abstract class TypeInferrerImpl extends TypeInferrer {
           }
 
           if (typeSchemaEnvironment.isSubtypeOf(receiverType, onType)) {
+            MemberBuilder memberBuilder =
+                setter ? setterBuilder : getterBuilder;
+
             ExtensionAccessCandidate candidate = new ExtensionAccessCandidate(
-                extension,
                 onType,
                 onTypeInstantiateToBounds,
-                new ObjectAccessTarget.extensionMember(
-                    memberBuilder.procedure,
-                    memberBuilder.extensionTearOff,
-                    memberBuilder.kind,
-                    inferredTypeArguments));
+                memberBuilder != null
+                    ? new ObjectAccessTarget.extensionMember(
+                        memberBuilder.procedure,
+                        memberBuilder.extensionTearOff,
+                        memberBuilder.kind,
+                        inferredTypeArguments)
+                    : const ObjectAccessTarget.missing(),
+                isPlatform: extensionBuilder.library.uri.scheme == 'dart');
             if (noneMoreSpecific.isNotEmpty) {
               bool isMostSpecific = true;
               for (ExtensionAccessCandidate other in noneMoreSpecific) {
@@ -2839,11 +2854,11 @@ class ExtensionAccessCandidate {
   final bool isPlatform;
   final DartType onType;
   final DartType onTypeInstantiateToBounds;
-  final ExtensionAccessTarget target;
+  final ObjectAccessTarget target;
 
-  ExtensionAccessCandidate(Extension extension, this.onType,
-      this.onTypeInstantiateToBounds, this.target)
-      : isPlatform = extension.enclosingLibrary.importUri.scheme == 'dart';
+  ExtensionAccessCandidate(
+      this.onType, this.onTypeInstantiateToBounds, this.target,
+      {this.isPlatform});
 
   bool isMoreSpecificThan(TypeSchemaEnvironment typeSchemaEnvironment,
       ExtensionAccessCandidate other) {

pkg/front_end/testcases/extensions/getter_setter_conflict.dart

@@ -0,0 +1,42 @@
+// Copyright (c) 2019, 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.
+
+class Class {
+  int get m1 => 0;
+  void set m2(int x) {}
+}
+
+extension Extension0 on Class {
+  void set m1(int x) {}
+  int get m2 => 0;
+  void set m3(int x) {}
+  int get m4 => 0;
+}
+
+extension Extension1 on Class {
+  int get m3 => 0;
+  void set m4(int x) {}
+}
+
+main() {
+  var c = new Class();
+  expect(0, c.m1);
+  c.m2 = 2;
+}
+
+errors() {
+  var c = new Class();
+  expect(0, c.m2);
+  c.m1 = 2;
+  c.m3;
+  c.m3 = 2;
+  c.m4;
+  c.m4 = 2;
+}
+
+expect(expected, actual) {
+  if (expected != actual) {
+    throw 'Mismatch: expected=$expected, actual=$actual';
+  }
+}

pkg/front_end/testcases/extensions/getter_setter_conflict.dart.outline.expect

@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    ;
+  get m1() → core::int*
+    ;
+  set m2(core::int* x) → void
+    ;
+}
+extension Extension0 on self::Class* {
+  get m2 = self::Extension0|get#m2;
+  get m4 = self::Extension0|get#m4;
+  set m1 = self::Extension0|set#m1;
+  set m3 = self::Extension0|set#m3;
+}
+extension Extension1 on self::Class* {
+  get m3 = self::Extension1|get#m3;
+  set m4 = self::Extension1|set#m4;
+}
+static method Extension0|set#m1(final self::Class* #this, core::int* x) → void
+  ;
+static method Extension0|get#m2(final self::Class* #this) → core::int*
+  ;
+static method Extension0|set#m3(final self::Class* #this, core::int* x) → void
+  ;
+static method Extension0|get#m4(final self::Class* #this) → core::int*
+  ;
+static method Extension1|get#m3(final self::Class* #this) → core::int*
+  ;
+static method Extension1|set#m4(final self::Class* #this, core::int* x) → void
+  ;
+static method main() → dynamic
+  ;
+static method errors() → dynamic
+  ;
+static method expect(dynamic expected, dynamic actual) → dynamic
+  ;

pkg/front_end/testcases/extensions/getter_setter_conflict.dart.strong.expect

@@ -0,0 +1,122 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+//   expect(0, c.m2);
+//               ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+//   c.m1 = 2;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The getter 'm3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm3'.
+//   c.m3;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The setter 'm3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm3'.
+//   c.m3 = 2;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The getter 'm4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm4'.
+//   c.m4;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The setter 'm4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm4'.
+//   c.m4 = 2;
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  get m1() → core::int*
+    return 0;
+  set m2(core::int* x) → void {}
+}
+extension Extension0 on self::Class* {
+  get m2 = self::Extension0|get#m2;
+  get m4 = self::Extension0|get#m4;
+  set m1 = self::Extension0|set#m1;
+  set m3 = self::Extension0|set#m3;
+}
+extension Extension1 on self::Class* {
+  get m3 = self::Extension1|get#m3;
+  set m4 = self::Extension1|set#m4;
+}
+static method Extension0|set#m1(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t1 = x;
+  return #t1;
+}
+static method Extension0|get#m2(final self::Class* #this) → core::int*
+  return 0;
+static method Extension0|set#m3(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t2 = x;
+  return #t2;
+}
+static method Extension0|get#m4(final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|get#m3(final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|set#m4(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t3 = x;
+  return #t3;
+}
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, c.{self::Class::m1});
+  c.{self::Class::m2} = 2;
+}
+static method errors() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+  expect(0, c.m2);
+              ^^");
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+  c.m1 = 2;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The getter 'm3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm3'.
+  c.m3;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The setter 'm3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm3'.
+  c.m3 = 2;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The getter 'm4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm4'.
+  c.m4;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The setter 'm4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm4'.
+  c.m4 = 2;
+    ^^";
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!expected.{core::Object::==}(actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}

pkg/front_end/testcases/extensions/getter_setter_conflict.dart.strong.transformed.expect

@@ -0,0 +1,122 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+//   expect(0, c.m2);
+//               ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+//   c.m1 = 2;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The getter 'm3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm3'.
+//   c.m3;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The setter 'm3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm3'.
+//   c.m3 = 2;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The getter 'm4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm4'.
+//   c.m4;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The setter 'm4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm4'.
+//   c.m4 = 2;
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  get m1() → core::int*
+    return 0;
+  set m2(core::int* x) → void {}
+}
+extension Extension0 on self::Class* {
+  get m2 = self::Extension0|get#m2;
+  get m4 = self::Extension0|get#m4;
+  set m1 = self::Extension0|set#m1;
+  set m3 = self::Extension0|set#m3;
+}
+extension Extension1 on self::Class* {
+  get m3 = self::Extension1|get#m3;
+  set m4 = self::Extension1|set#m4;
+}
+static method Extension0|set#m1(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t1 = x;
+  return #t1;
+}
+static method Extension0|get#m2(final self::Class* #this) → core::int*
+  return 0;
+static method Extension0|set#m3(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t2 = x;
+  return #t2;
+}
+static method Extension0|get#m4(final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|get#m3(final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|set#m4(final self::Class* #this, core::int* x) → core::int* {
+  final core::int* #t3 = x;
+  return #t3;
+}
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, c.{self::Class::m1});
+  c.{self::Class::m2} = 2;
+}
+static method errors() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+  expect(0, c.m2);
+              ^^");
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+  c.m1 = 2;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The getter 'm3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm3'.
+  c.m3;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The setter 'm3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm3'.
+  c.m3 = 2;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The getter 'm4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm4'.
+  c.m4;
+    ^^";
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The setter 'm4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm4'.
+  c.m4 = 2;
+    ^^";
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!expected.{core::Object::==}(actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}

pkg/front_end/testcases/text_serialization.status

@@ -17,6 +17,7 @@ extensions/explicit_extension_inference: TextSerializationFailure
 extensions/explicit_generic_extension_access: TextSerializationFailure
 extensions/explicit_this: TextSerializationFailure
 extensions/extension_methods: TextSerializationFailure
+extensions/getter_setter_conflict: TextSerializationFailure
 extensions/implicit_extension_inference: TextSerializationFailure
 extensions/implicit_this: TextSerializationFailure
 extensions/index: TextSerializationFailure