Reapply "Implement new model for class members." and "Implement new model for interface members."

tests/compiler/dart2js/members_test.dart

+// Copyright (c) 2014, 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.
+
+library members_test;
+
+import 'package:expect/expect.dart';
+import "package:async_helper/async_helper.dart";
+import 'type_test_helper.dart';
+import '../../../sdk/lib/_internal/compiler/implementation/dart_types.dart';
+import "../../../sdk/lib/_internal/compiler/implementation/elements/elements.dart"
+       show Element, ClassElement, MemberSignature, Name, PublicName;
+import "../../../sdk/lib/_internal/compiler/implementation/resolution/class_members.dart"
+  show SyntheticMember, ErroneousMember;
+
+void main() {
+  testClassMembers();
+  testInterfaceMembers();
+  testClassVsInterfaceMembers();
+  testMixinMembers();
+}
+
+MemberSignature getMember(InterfaceType cls, String name,
+                          {bool isSetter: false,
+                           int checkType: CHECK_INTERFACE}) {
+  Name memberName =
+      new Name(name, cls.element.getLibrary(), isSetter: isSetter);
+  MemberSignature member = checkType == CHECK_CLASS
+        ? cls.element.lookupClassMember(memberName)
+        : cls.element.lookupInterfaceMember(memberName);
+  if (member != null) {
+    Expect.equals(memberName, member.name);
+  }
+  return member;
+}
+
+/// Check interface member only.
+const int CHECK_INTERFACE = 0;
+/// Check class member only.
+const int CHECK_CLASS = 1;
+/// Check that there is no class member for the interface member.
+const int NO_CLASS_MEMBER = 2;
+/// Check that the interface member is also a class member.
+const int ALSO_CLASS_MEMBER = 3;
+
+/**
+ * Checks [member] or interface member [name] of the declaration of [cls].
+ *
+ * If [inheritFrom] is set, the member from [cls] must be identical to the
+ * member from [inheritedFrom].
+ *
+ * Otherwise, the properties of member are checked against the values of
+ * [isStatic], [isSetter], [isGetter], [declarer], [type] and
+ * [functionType].
+ *
+ * If [synthesizedFrom] or [erroneousFrom] is not `null`, the member is checked
+ * to be synthesized for the corresponding members found on the type is
+ * [synthesizedFrom] or  or [erroneousFrom], respectively.
+ * Otherwise, if [declarer] is `null`, the declarer is checked to be [cls], and
+ * if [declarer] is not `null`, the declarer is checked to be [declarer].
+ * If [type] is `null` it is checked that the type of the member is also the
+ * member type, otherwise the type is checked to be [type].
+ *
+ * If [isClassMember] is `true` it is checked that the member is also a class
+ * member.
+ */
+MemberSignature checkMember(InterfaceType cls,
+                      String name,
+                      {bool isStatic: false,
+                       bool isSetter: false,
+                       bool isGetter: false,
+                       InterfaceType declarer,
+                       DartType type,
+                       FunctionType functionType,
+                       InterfaceType inheritedFrom,
+                       List<InterfaceType> synthesizedFrom,
+                       List<InterfaceType> erroneousFrom,
+                       int checkType: ALSO_CLASS_MEMBER}) {
+  String memberKind = checkType == CHECK_CLASS ? 'class' : 'interface';
+  MemberSignature member =
+      getMember(cls, name, isSetter: isSetter, checkType: checkType);
+  Expect.isNotNull(member, "No $memberKind member '$name' in $cls.");
+  Name memberName = member.name;
+  if (checkType == ALSO_CLASS_MEMBER) {
+    MemberSignature classMember = cls.element.lookupClassMember(memberName);
+    Expect.isNotNull(classMember, "No class member '$memberName' in $cls.");
+    Expect.equals(member, classMember);
+  } else if (checkType == NO_CLASS_MEMBER) {
+    Expect.isNull(cls.element.lookupClassMember(memberName));
+  }
+
+  if (inheritedFrom != null) {
+    MemberSignature inherited = checkType == CHECK_CLASS
+        ? inheritedFrom.element.lookupClassMember(memberName)
+        : inheritedFrom.element.lookupInterfaceMember(memberName);
+    Expect.isNotNull(inherited,
+        "No $memberKind member '$memberName' in $inheritedFrom.");
+    Expect.equals(inherited.inheritFrom(inheritedFrom), member);
+  } else {
+    if (erroneousFrom != null || synthesizedFrom != null) {
+      Expect.notEquals(checkType, CHECK_CLASS,
+          "Arguments 'erroneousFrom' and 'synthesizedFrom' only apply "
+          "to interface members.");
+      if (synthesizedFrom != null) {
+        Expect.isTrue(member is SyntheticMember,
+            "Member '$member' is not synthesized.");
+      } else {
+        Expect.isTrue(member is ErroneousMember,
+            "Member '$member' is not erroneous.");
+      }
+      Set<MemberSignature> members = new Set<MemberSignature>();
+      List from = synthesizedFrom != null ? synthesizedFrom : erroneousFrom;
+      for (InterfaceType type in from) {
+        MemberSignature inheritedMember =
+            type.element.lookupInterfaceMember(memberName);
+        Expect.isNotNull(inheritedMember);
+        members.add(inheritedMember.inheritFrom(type));
+      }
+      Expect.setEquals(members, member.declarations);
+    } else if (declarer != null) {
+      Expect.equals(declarer, member.declarer,
+          "Unexpected declarer '${member.declarer}' of $memberKind member "
+          "'$member'. Expected '${declarer}'.");
+    } else {
+      Expect.equals(cls.element, member.element.getEnclosingClass());
+      Expect.equals(cls, member.declarer);
+    }
+    Expect.equals(isSetter, member.isSetter);
+    Expect.equals(isGetter, member.isGetter);
+    if (type != null) {
+      Expect.equals(type, member.type,
+          "Unexpected type of $memberKind member '$member'.");
+    }
+    if (functionType != null) {
+      if (type == null) {
+        Expect.equals(member.type, member.functionType,
+          "Unexpected type of $memberKind member '$member'.");
+      }
+      Expect.equals(functionType, member.functionType,
+          "Unexpected member type of $memberKind member '$member'.");
+    }
+  }
+  return member;
+}
+
+void checkMemberCount(InterfaceType cls, int expectedCount,
+                      {bool interfaceMembers: true}) {
+  int count = 0;
+  if (interfaceMembers) {
+    cls.element.forEachInterfaceMember((_) => count++);
+  } else {
+    cls.element.forEachClassMember((_) => count++);
+  }
+  Expect.equals(expectedCount, count);
+}
+
+void testClassMembers() {
+  asyncTest(() => TypeEnvironment.create(r"""
+    abstract class A {
+      int field;
+      final finalField = 0;
+      static var staticField;
+
+      int get getter => 0;
+      get abstractGetter;
+      void set setter(int _) {}
+      set abstractSetter(_);
+
+      method() {}
+      abstractMethod();
+      static staticMethod() {} 
+    }
+    class B<T> {
+      T field;
+      void method(T t) {}
+      static staticMethod() {}
+      toString([T t]) {}
+    }
+    class C<S> extends B<S> {}
+    class D extends C<int> {}
+    class E extends D {}
+    """, useMockCompiler: false).then((env) {
+
+    InterfaceType bool_ = env['bool'];
+    InterfaceType String_ = env['String'];
+    InterfaceType num_ = env['num'];
+    InterfaceType int_ = env['int'];
+    InterfaceType dynamic_ = env['dynamic'];
+    VoidType void_ = env['void'];
+    InterfaceType Type_ = env['Type'];
+    InterfaceType Invocation_ = env['Invocation'];
+
+    InterfaceType Object_ = env['Object'];
+    checkMemberCount(Object_, 5 /*declared*/, interfaceMembers: true);
+    checkMemberCount(Object_, 5 /*declared*/, interfaceMembers: false);
+
+    checkMember(Object_, '==',
+                functionType: env.functionType(bool_, [dynamic_]));
+    checkMember(Object_, 'hashCode',
+                isGetter: true,
+                type: int_, functionType: env.functionType(int_, []));
+    checkMember(Object_, 'noSuchMethod',
+                functionType: env.functionType(dynamic_, [Invocation_]));
+    checkMember(Object_, 'runtimeType',
+                isGetter: true,
+                type: Type_, functionType: env.functionType(Type_, []));
+    checkMember(Object_, 'toString',
+                functionType: env.functionType(String_, []));
+
+    InterfaceType A = env['A'];
+    checkMemberCount(A, 5 /*inherited*/ + 9 /*non-static declared*/,
+                     interfaceMembers: true);
+    checkMemberCount(A, 5 /*inherited*/ + 9 /*non-abstract declared*/,
+                     interfaceMembers: false);
+
+    checkMember(A, '==', inheritedFrom: Object_);
+    checkMember(A, 'hashCode', inheritedFrom: Object_);
+    checkMember(A, 'noSuchMethod', inheritedFrom: Object_);
+    checkMember(A, 'runtimeType', inheritedFrom: Object_);
+    checkMember(A, 'toString', inheritedFrom: Object_);
+
+    checkMember(A, 'field', isGetter: true,
+                type: int_, functionType: env.functionType(int_, []));
+    checkMember(A, 'field', isSetter: true,
+                type: int_, functionType: env.functionType(void_, [int_]));
+    checkMember(A, 'finalField', isGetter: true,
+                type: dynamic_, functionType: env.functionType(dynamic_, []));
+    checkMember(A, 'staticField', isGetter: true, isStatic: true,
+                checkType: CHECK_CLASS,
+                type: dynamic_, functionType: env.functionType(dynamic_, []));
+    checkMember(A, 'staticField', isSetter: true, isStatic: true,
+                checkType: CHECK_CLASS, type: dynamic_,
+                functionType: env.functionType(void_, [dynamic_]));
+
+    checkMember(A, 'getter', isGetter: true,
+                type: int_, functionType: env.functionType(int_, []));
+    checkMember(A, 'abstractGetter', isGetter: true,
+                checkType: NO_CLASS_MEMBER,
+                type: dynamic_, functionType: env.functionType(dynamic_, []));
+    checkMember(A, 'setter', isSetter: true,
+                type: int_, functionType: env.functionType(void_, [int_]));
+    checkMember(A, 'abstractSetter', isSetter: true,
+                checkType: NO_CLASS_MEMBER, type: dynamic_,
+                functionType: env.functionType(dynamic_, [dynamic_]));
+
+    checkMember(A, 'method', functionType: env.functionType(dynamic_, []));
+    checkMember(A, 'abstractMethod',
+                checkType: NO_CLASS_MEMBER,
+                functionType: env.functionType(dynamic_, []));
+    checkMember(A, 'staticMethod',
+                checkType: CHECK_CLASS,
+                isStatic: true, functionType: env.functionType(dynamic_, []));
+
+    ClassElement B = env.getElement('B');
+    InterfaceType B_this = B.thisType;
+    TypeVariableType B_T = B_this.typeArguments.head;
+    checkMemberCount(B_this, 4 /*inherited*/ + 4 /*non-static declared*/,
+                     interfaceMembers: true);
+    checkMemberCount(B_this, 4 /*inherited*/ + 5 /*declared*/,
+                     interfaceMembers: false);
+
+    checkMember(B_this, '==', inheritedFrom: Object_);
+    checkMember(B_this, 'hashCode', inheritedFrom: Object_);
+    checkMember(B_this, 'noSuchMethod', inheritedFrom: Object_);
+    checkMember(B_this, 'runtimeType', inheritedFrom: Object_);
+
+    checkMember(B_this, 'field', isGetter: true,
+                type: B_T, functionType: env.functionType(B_T, []));
+    checkMember(B_this, 'field', isSetter: true,
+                type: B_T, functionType: env.functionType(void_, [B_T]));
+    checkMember(B_this, 'method', functionType: env.functionType(void_, [B_T]));
+    checkMember(B_this, 'staticMethod',
+                checkType: CHECK_CLASS,
+                isStatic: true, functionType: env.functionType(dynamic_, []));
+    checkMember(B_this, 'toString',
+                functionType: env.functionType(dynamic_, [],
+                                               optionalParameters: [B_T]));
+
+    ClassElement C = env.getElement('C');
+    InterfaceType C_this = C.thisType;
+    TypeVariableType C_S = C_this.typeArguments.head;
+    checkMemberCount(C_this, 8 /*inherited*/, interfaceMembers: true);
+    checkMemberCount(C_this, 8 /*inherited*/, interfaceMembers: false);
+    InterfaceType B_S = instantiate(B, [C_S]);
+
+    checkMember(C_this, '==', inheritedFrom: Object_);
+    checkMember(C_this, 'hashCode', inheritedFrom: Object_);
+    checkMember(C_this, 'noSuchMethod', inheritedFrom: Object_);
+    checkMember(C_this, 'runtimeType', inheritedFrom: Object_);
+
+    checkMember(C_this, 'field', isGetter: true,
+                declarer: B_S,
+                type: C_S, functionType: env.functionType(C_S, []));
+    checkMember(C_this, 'field', isSetter: true,
+                 declarer: B_S,
+                 type: C_S, functionType: env.functionType(void_, [C_S]));
+    checkMember(C_this, 'method',
+                declarer: B_S,
+                functionType: env.functionType(void_, [C_S]));
+    checkMember(C_this, 'toString',
+                declarer: B_S,
+                functionType: env.functionType(dynamic_, [],
+                                               optionalParameters: [C_S]));
+
+    InterfaceType D = env['D'];
+    checkMemberCount(D, 8 /*inherited*/, interfaceMembers: true);
+    checkMemberCount(D, 8 /*inherited*/, interfaceMembers: false);
+    InterfaceType B_int = instantiate(B, [int_]);
+
+    checkMember(D, '==', inheritedFrom: Object_);
+    checkMember(D, 'hashCode', inheritedFrom: Object_);
+    checkMember(D, 'noSuchMethod', inheritedFrom: Object_);
+    checkMember(D, 'runtimeType', inheritedFrom: Object_);
+
+    checkMember(D, 'field', isGetter: true,
+                declarer: B_int,
+                type: int_, functionType: env.functionType(int_, []));
+    checkMember(D, 'field', isSetter: true,
+                declarer: B_int,
+                type: int_, functionType: env.functionType(void_, [int_]));
+    checkMember(D, 'method',
+                declarer: B_int,
+                functionType: env.functionType(void_, [int_]));
+    checkMember(D, 'toString',
+                declarer: B_int,
+                functionType: env.functionType(dynamic_, [],
+                                               optionalParameters: [int_]));
+
+    InterfaceType E = env['E'];
+    checkMemberCount(E, 8 /*inherited*/, interfaceMembers: true);
+    checkMemberCount(E, 8 /*inherited*/, interfaceMembers: false);
+
+    checkMember(E, '==', inheritedFrom: Object_);
+    checkMember(E, 'hashCode', inheritedFrom: Object_);
+    checkMember(E, 'noSuchMethod', inheritedFrom: Object_);
+    checkMember(E, 'runtimeType', inheritedFrom: Object_);
+
+    checkMember(E, 'field', isGetter: true,
+                declarer: B_int,
+                type: int_, functionType: env.functionType(int_, []));
+    checkMember(E, 'field', isSetter: true,
+                declarer: B_int,
+                type: int_, functionType: env.functionType(void_, [int_]));
+    checkMember(E, 'method',
+                declarer: B_int,
+                functionType: env.functionType(void_, [int_]));
+    checkMember(E, 'toString',
+                declarer: B_int,
+                functionType: env.functionType(dynamic_, [],
+                                               optionalParameters: [int_]));
+  }));
+}
+
+void testInterfaceMembers() {
+  asyncTest(() => TypeEnvironment.create(r"""
+    abstract class A {
+      num method1();
+      void method2();
+      void method3();
+      void method4();
+      method5(a);
+      method6(a);
+      method7(a);
+      method8(a, b);
+      method9(a, b, c);
+      method10(a, {b, c});
+      method11(a, {b, c});
+      num get getter1;
+      num get getter2;
+      void set setter1(num _);
+      void set setter2(num _);
+      void set setter3(num _);
+      get getterAndMethod;
+    }
+    abstract class B {
+      int method1();
+      int method2();
+      num method3();
+      num method4();
+      method5([a]);
+      method6([a, b]);
+      method7(a, [b]);
+      method8([a]);
+      method9(a, [b]);
+      method10(a, {c, d});
+      method11(a, b, {c, d});
+      num get getter1;
+      int get getter2;
+      void set setter1(num _);
+      set setter2(num _);
+      void set setter3(int _);
+      getterAndMethod();
+    }
+    abstract class C {
+      int method3();
+      num method4();
+    }
+    abstract class D implements A, B, C {}
+    """).then((env) {
+
+    InterfaceType dynamic_ = env['dynamic'];
+    VoidType void_ = env['void'];
+    InterfaceType num_ = env['num'];
+    InterfaceType int_ = env['int'];
+
+    InterfaceType A = env['A'];
+    InterfaceType B = env['B'];
+    InterfaceType C = env['C'];
+    InterfaceType D = env['D'];
+
+    // A: num method1()
+    // B: int method1()
+    // D: dynamic method1() -- synthesized from A and B.
+    checkMember(D, 'method1',
+        synthesizedFrom: [A, B],
+        functionType: env.functionType(dynamic_ , []),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: void method2()
+    // B: int method2()
+    // D: int method2() -- inherited from B
+    checkMember(D, 'method2', inheritedFrom: B, checkType: NO_CLASS_MEMBER);
+
+    // A: void method3()
+    // B: num method3()
+    // C: int method3()
+    // D: dynamic method3() -- synthesized from A, B, and C.
+    checkMember(D, 'method3',
+        synthesizedFrom: [A, B, C],
+        functionType: env.functionType(dynamic_ , []),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: void method4()
+    // B: num method4()
+    // C: num method4()
+    // D: num method4() -- synthesized from B and C.
+    checkMember(D, 'method4',
+        synthesizedFrom: [B, C],
+        functionType: env.functionType(num_, []),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: method5(a)
+    // B: method5([a])
+    // D: method5([a]) -- inherited from B
+    checkMember(D, 'method5', inheritedFrom: B, checkType: NO_CLASS_MEMBER);
+
+    // A: method6(a)
+    // B: method6([a, b])
+    // D: method6([a, b]) -- inherited from B
+    checkMember(D, 'method6', inheritedFrom: B, checkType: NO_CLASS_MEMBER);
+
+    // A: method7(a)
+    // B: method7(a, [b])
+    // D: method7(a, [b]) -- inherited from B
+    checkMember(D, 'method7', inheritedFrom: B, checkType: NO_CLASS_MEMBER);
+
+    // A: method8(a, b)
+    // B: method8([a])
+    // D: method8([a, b]) -- synthesized from A and B.
+    checkMember(D, 'method8',
+        synthesizedFrom: [A, B],
+        functionType: env.functionType(
+            dynamic_, [], optionalParameters: [dynamic_, dynamic_]),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: method9(a, b, c)
+    // B: method9(a, [b])
+    // D: method9(a, [b, c]) -- synthesized from A and B.
+    checkMember(D, 'method9',
+        synthesizedFrom: [A, B],
+        functionType: env.functionType(
+            dynamic_, [dynamic_], optionalParameters: [dynamic_, dynamic_]),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: method10(a, {b, c})
+    // B: method10(a, {c, d})
+    // D: method10(a, {b, c, d}) -- synthesized from A and B.
+    checkMember(D, 'method10',
+        synthesizedFrom: [A, B],
+        functionType: env.functionType(dynamic_, [dynamic_],
+                                       namedParameters: {'b': dynamic_,
+                                                         'c': dynamic_,
+                                                         'd': dynamic_}),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: method11(a, {b, c})
+    // B: method11(a, b, {c, d})
+    // D: method11(a, [b], {c, d}) -- synthesized from A and B.
+    // TODO(johnniwinther): Change to check synthesized member when function
+    // types with both optional and named parameters are supported.
+    Expect.isNull(getMember(D, 'method11'));
+    /*checkMember(D, 'method11',
+        synthesizedFrom: [A, B],
+        functionType: env.functionType(dynamic_, [dynamic_],
+                                       optionalParameters: [dynamic_],
+                                       namedParameters: {'c': dynamic_,
+                                                         'd': dynamic_,}),
+        checkType: NO_CLASS_MEMBER);*/
+
+    // A: num get getter1
+    // B: num get getter1
+    // D: num get getter1 -- synthesized from A and B.
+    checkMember(D, 'getter1',
+        isGetter: true,
+        synthesizedFrom: [A, B], type: num_,
+        functionType: env.functionType(num_ , []),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: num get getter2
+    // B: int get getter2
+    // D: dynamic get getter2 -- synthesized from A and B.
+    checkMember(D, 'getter2',
+        isGetter: true,
+        synthesizedFrom: [A, B], type: dynamic_,
+        functionType: env.functionType(dynamic_ , []),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: void set setter1(num _)
+    // B: void set setter1(num _)
+    // D: void set setter1(num _) -- synthesized from A and B.
+    checkMember(D, 'setter1',
+        isSetter: true,
+        synthesizedFrom: [A, B], type: num_,
+        functionType: env.functionType(void_ , [num_]),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: void set setter2(num _)
+    // B: set setter2(num _)
+    // D: dynamic set setter2(dynamic _) -- synthesized from A and B.
+    checkMember(D, 'setter2',
+        isSetter: true,
+        synthesizedFrom: [A, B], type: dynamic_,
+        functionType: env.functionType(dynamic_ , [dynamic_]),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: void set setter3(num _)
+    // B: void set setter3(int _)
+    // D: dynamic set setter3(dynamic _) -- synthesized from A and B.
+    checkMember(D, 'setter3',
+        isSetter: true,
+        synthesizedFrom: [A, B], type: dynamic_,
+        functionType: env.functionType(dynamic_ , [dynamic_]),
+        checkType: NO_CLASS_MEMBER);
+
+    // A: get getterAndMethod
+    // B: getterAndMethod()
+    // D: nothing inherited
+    checkMember(D, 'getterAndMethod',
+        erroneousFrom: [A, B],
+        checkType: NO_CLASS_MEMBER);
+  }));
+}
+
+void testClassVsInterfaceMembers() {
+  asyncTest(() => TypeEnvironment.create(r"""
+    class A {
+      method1() {}
+      method2() {}
+    }
+    abstract class B {
+      method1(); 
+      method2(a);
+    }
+    abstract class C extends A implements B {}
+    """).then((env) {
+
+    InterfaceType dynamic_ = env['dynamic'];
+    VoidType void_ = env['void'];
+    InterfaceType num_ = env['num'];
+    InterfaceType int_ = env['int'];
+
+    InterfaceType A = env['A'];
+    InterfaceType B = env['B'];
+    InterfaceType C = env['C'];
+
+    // A: method1()
+    // B: method1()
+    // C class: method1() -- inherited from A.
+    // C interface: dynamic method1() -- synthesized from A and B.
+    MemberSignature interfaceMember =
+        checkMember(C, 'method1', checkType: CHECK_INTERFACE,
+                    synthesizedFrom: [A, B],
+                    functionType: env.functionType(dynamic_ , []));
+    MemberSignature classMember =
+        checkMember(C, 'method1', checkType: CHECK_CLASS, inheritedFrom: A);
+    Expect.notEquals(interfaceMember, classMember);
+
+    // A: method2()
+    // B: method2(a)
+    // C class: method2() -- inherited from A.
+    // C interface: dynamic method2([a]) -- synthesized from A and B.
+    interfaceMember =
+        checkMember(C, 'method2', checkType: CHECK_INTERFACE,
+                    synthesizedFrom: [A, B],
+                    functionType: env.functionType(dynamic_ , [],
+                        optionalParameters: [dynamic_]));
+    classMember =
+        checkMember(C, 'method2', checkType: CHECK_CLASS, inheritedFrom: A);
+    Expect.notEquals(interfaceMember, classMember);
+  }));
+}
+
+
+void testMixinMembers() {
+  asyncTest(() => TypeEnvironment.create(r"""
+    class A<T> {
+      method1() {}
+      method2() {}
+      method3(T a) {}
+      method4(T a) {}
+    }
+    abstract class B<S> {
+      method1(); 
+      method2(a);
+      method3(S a) {}
+    }
+    abstract class C<U, V> extends Object with A<U> implements B<V> {}
+    """).then((env) {
+
+    InterfaceType dynamic_ = env['dynamic'];
+    VoidType void_ = env['void'];
+    InterfaceType num_ = env['num'];
+    InterfaceType int_ = env['int'];
+
+    ClassElement A = env.getElement('A');
+    ClassElement B = env.getElement('B');
+    ClassElement C = env.getElement('C');
+    InterfaceType C_this = C.thisType;
+    TypeVariableType C_U = C_this.typeArguments.head;
+    TypeVariableType C_V = C_this.typeArguments.tail.head;
+    InterfaceType A_U = instantiate(A, [C_U]);
+    InterfaceType B_V = instantiate(B, [C_V]);
+
+    // A: method1()
+    // B: method1()
+    // C class: method1() -- inherited from A.
+    // C interface: dynamic method1() -- synthesized from A and B.
+    MemberSignature interfaceMember =
+        checkMember(C_this, 'method1', checkType: CHECK_INTERFACE,
+                    synthesizedFrom: [A_U, B_V],
+                    functionType: env.functionType(dynamic_ , []));
+    MemberSignature classMember =
+        checkMember(C_this, 'method1', checkType: CHECK_CLASS,
+                    inheritedFrom: A_U);
+    Expect.notEquals(interfaceMember, classMember);
+
+    // A: method2()
+    // B: method2(a)
+    // C class: method2() -- inherited from A.
+    // C interface: dynamic method2([a]) -- synthesized from A and B.
+    interfaceMember =
+        checkMember(C_this, 'method2', checkType: CHECK_INTERFACE,
+                    synthesizedFrom: [A_U, B_V],
+                    functionType: env.functionType(dynamic_ , [],
+                        optionalParameters: [dynamic_]));
+    classMember =
+        checkMember(C_this, 'method2', checkType: CHECK_CLASS,
+                    inheritedFrom: A_U);
+    Expect.notEquals(interfaceMember, classMember);
+
+    // A: method3(U a)
+    // B: method3(V a)
+    // C class: method3(U a) -- inherited from A.
+    // C interface: dynamic method3(a) -- synthesized from A and B.
+    interfaceMember =
+        checkMember(C_this, 'method3', checkType: CHECK_INTERFACE,
+                    synthesizedFrom: [A_U, B_V],
+                    functionType: env.functionType(dynamic_ , [dynamic_]));
+    classMember =
+        checkMember(C_this, 'method3', checkType: CHECK_CLASS,
+                    inheritedFrom: A_U);
+    Expect.notEquals(interfaceMember, classMember);
+
+    // A: method4(U a)
+    // B: --
+    // C class: method4(U a) -- inherited from A.
+    // C interface: method4(U a) -- inherited from A.
+    checkMember(C_this, 'method4', checkType: ALSO_CLASS_MEMBER,
+                inheritedFrom: A_U);
+  }));
+}