Add type inference for super property gets.

pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart

 // Copyright (c) 2017, 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.
 
 /// This file declares a "shadow hierarchy" of concrete classes which extend
 /// the kernel class hierarchy, adding methods and fields needed by the
 /// BodyBuilder.
 ///
 /// Instances of these classes may be created using the factory methods in
 /// `ast_factory.dart`.
@@ skipping 538 matching lines @@
         interfaceMember: target, methodName: target.name, arguments: arguments);
   }
 }
 
 /// Shadow object for [DirectPropertyGet].
 class KernelDirectPropertyGet extends DirectPropertyGet
     implements KernelExpression {
   KernelDirectPropertyGet(Expression receiver, Member target)
       : super(receiver, target);
 
-  KernelDirectPropertyGet.byReference(
-      Expression receiver, Reference targetReference)
-      : super.byReference(receiver, targetReference);
-
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
-    // TODO(paulberry): Determine the right thing to do here.
-    throw 'TODO(paulberry)';
+    // DirectPropertyGet can only occur as a result of a use of `super`, and
+    // `super` can't appear inside a field initializer.  So this code should
+    // never be reached.
+    internalError(
+        'Unexpected call to _collectDependencies for DirectPropertyGet');
   }
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
-    // TODO(scheglov): implement.
-    return typeNeeded ? const DynamicType() : null;
+    return inferrer.inferPropertyGet(
+        this, receiver, fileOffset, typeContext, typeNeeded,
+        propertyName: target.name);
   }
 }
 
 /// Concrete shadow object representing a do loop in kernel form.
 class KernelDoStatement extends DoStatement implements KernelStatement {
   KernelDoStatement(Statement body, Expression condition)
       : super(body, condition);
 
   @override
   void _inferStatement(KernelTypeInferrer inferrer) {
@@ skipping 790 matching lines @@
 
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
     // Null aware expressions are not immediately evident.
     collector.recordNotImmediatelyEvident(fileOffset);
   }
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
-    var inferredType = inferrer.inferPropertyGet(
-        this,
-        variable.initializer,
-        fileOffset,
-        _desugaredGet,
-        typeContext,
-        typeNeeded || inferrer.strongMode,
-        receiverVariable: variable);
+    var inferredType = inferrer.inferPropertyGet(this, variable.initializer,
+        fileOffset, typeContext, typeNeeded || inferrer.strongMode,
+        receiverVariable: variable, desugaredGet: _desugaredGet);
     if (inferrer.strongMode) {
       body.staticType = inferredType;
     }
     return inferredType;
   }
 }
 
 /// Concrete shadow object representing a null literal in kernel form.
 class KernelNullLiteral extends NullLiteral implements KernelExpression {
   @override
@@ skipping 153 matching lines @@
     // For a property get, the only things we could be looking at are an
     // instance field, an instance getter, or an instance method.  For the first
     // two, we disallow them in [_inferExpression].  For the last, there are no
     // field dependencies.  So we don't need to do anything here.
   }
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
     return inferrer.inferPropertyGet(
-        this, receiver, fileOffset, this, typeContext, typeNeeded);
+        this, receiver, fileOffset, typeContext, typeNeeded,
+        desugaredGet: this);
   }
 }
 
 /// Concrete shadow object representing a redirecting initializer in kernel
 /// form.
 class KernelRedirectingInitializer extends RedirectingInitializer
     implements KernelInitializer {
   KernelRedirectingInitializer(Constructor target, Arguments arguments)
       : super(target, arguments);
 
@@ skipping 213 matching lines @@
   }
 }
 
 /// Shadow object for [SuperMethodInvocation].
 class KernelSuperMethodInvocation extends SuperMethodInvocation
     implements KernelExpression {
   KernelSuperMethodInvocation(Name name, Arguments arguments,
       [Procedure interfaceTarget])
       : super(name, arguments, interfaceTarget);
 
-  KernelSuperMethodInvocation.byReference(
-      Name name, Arguments arguments, Reference interfaceTargetReference)
-      : super.byReference(name, arguments, interfaceTargetReference);
-
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
     // Super expressions should never occur in top level type inference.
     // TODO(paulberry): but could they occur due to invalid code?
     assert(false);
   }
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
     inferrer.instrumentation?.record(Uri.parse(inferrer.uri), fileOffset,
         'target', new InstrumentationValueForMember(interfaceTarget));
     return inferrer.inferMethodInvocation(this, new KernelThisExpression(),
         fileOffset, false, typeContext, typeNeeded,
         interfaceMember: interfaceTarget,
         methodName: name,
         arguments: arguments);
   }
 }
 
 /// Shadow object for [SuperPropertyGet].
 class KernelSuperPropertyGet extends SuperPropertyGet
     implements KernelExpression {
   KernelSuperPropertyGet(Name name, [Member interfaceTarget])
       : super(name, interfaceTarget);
 
-  KernelSuperPropertyGet.byReference(
-      Name name, Reference interfaceTargetReference)
-      : super.byReference(name, interfaceTargetReference);
-
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
     // Super expressions should never occur in top level type inference.
     // TODO(paulberry): but could they occur due to invalid code?
     assert(false);
   }
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
-    // TODO(scheglov): implement.
-    return typeNeeded ? const DynamicType() : null;
+    return inferrer.inferPropertyGet(
+        this, new KernelThisExpression(), fileOffset, typeContext, typeNeeded,
+        propertyName: name);
   }
 }
 
 /// Concrete shadow object representing a switch statement in kernel form.
 class KernelSwitchStatement extends SwitchStatement implements KernelStatement {
   KernelSwitchStatement(Expression expression, List<SwitchCase> cases)
       : super(expression, cases);
 
   @override
   void _inferStatement(KernelTypeInferrer inferrer) {
@@ skipping 477 matching lines @@
   }
 
   transformChildren(v) {
     return internalError("Internal error: Unsupported operation.");
   }
 
   visitChildren(v) {
     return internalError("Internal error: Unsupported operation.");
   }
 }