Refactoring resolution of local access and unqualified access of statics

pkg/compiler/lib/src/resolution/members.dart

 // Copyright (c) 2012, 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.
 
 part of resolution;
 
 /**
  * Core implementation of resolution.
  *
  * Do not subclass or instantiate this class outside this library
@@ skipping 786 matching lines @@
   /// Check that access to `this` is currently allowed.
   bool checkThisAccess(Send node) {
     if (!inInstanceContext) {
       compiler.reportError(node, MessageKind.NO_THIS_AVAILABLE);
       return false;
     }
     return true;
   }
 
   /// Compute the [AccessSemantics] corresponding to a super access of [target].
-  AccessSemantics computeSuperAccess(Spannable node, Element target) {
+  AccessSemantics computeSuperAccessSemantics(Spannable node, Element target) {
     if (target.isErroneous) {
       return new StaticAccess.unresolvedSuper(target);
     } else if (target.isGetter) {
       return new StaticAccess.superGetter(target);
     } else if (target.isSetter) {
       return new StaticAccess.superSetter(target);
     } else if (target.isField) {
-      return new StaticAccess.superField(target);
+      if (target.isFinal) {
+        return new StaticAccess.superFinalField(target);
+      } else {
+        return new StaticAccess.superField(target);
+      }
     } else {
       assert(invariant(node, target.isFunction,
           message: "Unexpected super target '$target'."));
       return new StaticAccess.superMethod(target);
     }
   }
 
+  /// Compute the [AccessSemantics] corresponding to a local access of [target].
+  AccessSemantics computeLocalAccessSemantics(Spannable node,
+                                              LocalElement target) {
+    if (target.isParameter) {
+      if (target.isFinal || target.isConst) {
+        return new StaticAccess.finalParameter(target);
+      } else {
+        return new StaticAccess.parameter(target);
+      }
+    } else if (target.isVariable) {
+      if (target.isFinal || target.isConst) {
+        return new StaticAccess.finalLocalVariable(target);
+      } else {
+        return new StaticAccess.localVariable(target);
+      }
+    } else {
+      assert(invariant(node, target.isFunction,
+          message: "Unexpected local target '$target'."));
+      return new StaticAccess.localFunction(target);
+    }
+  }
+
+  /// Compute the [AccessSemantics] corresponding to a static or toplevel access
+  /// of [target].
+  AccessSemantics computeStaticOrTopLevelAccessSemantics(
+      Spannable node,
+      Element target) {
+
+    target = target.declaration;
+    if (target.isErroneous) {
+      // This handles elements with parser errors.
+      // TODO(johnniwinther): Elements with parse error should not set
+      // [isErroneous] to `true`.
+      return new StaticAccess.unresolved(target);
+    }
+    if (target.isStatic) {
+      if (target.isGetter) {
+        return new StaticAccess.staticGetter(target);
+      } else if (target.isSetter) {
+        return new StaticAccess.staticSetter(target);
+      } else if (target.isField) {
+        if (target.isFinal || target.isConst) {
+          return new StaticAccess.finalStaticField(target);
+        } else {
+          return new StaticAccess.staticField(target);
+        }
+      } else {
+        assert(invariant(node, target.isFunction,
+            message: "Unexpected static target '$target'."));
+        return new StaticAccess.staticMethod(target);
+      }
+     } else {
+       assert(invariant(node, target.isTopLevel,
+           message: "Unexpected staticall resolved target '$target'."));

[karlklose, 2015/06/08 09:05:30]

'staticall' -> 'statically'.

[Johnni Winther, 2015/06/08 09:36:14]

Done.

+       if (target.isGetter) {
+         return new StaticAccess.topLevelGetter(target);
+       } else if (target.isSetter) {
+         return new StaticAccess.topLevelSetter(target);
+       } else if (target.isField) {
+         if (target.isFinal) {
+           return new StaticAccess.finalTopLevelField(target);
+         } else {
+           return new StaticAccess.topLevelField(target);
+         }
+       } else {
+         assert(invariant(node, target.isFunction,
+             message: "Unexpected top level target '$target'."));
+         return new StaticAccess.topLevelMethod(target);
+       }
+     }
+  }
+
   /// Compute the [AccessSemantics] for accessing the name of [selector] on the
   /// super class.
   ///
   /// If no matching super member is found and error is reported and
   /// `noSuchMethod` on `super` is registered. Furthermore, if [alternateName]
   /// is provided, the [AccessSemantics] corresponding to the alternate name is
   /// returned. For instance, the access of a super setter for an unresolved
   /// getter:
   ///
   ///     class Super {
   ///       set name(_) {}
   ///     }
   ///     class Sub extends Super {
   ///       foo => super.name; // Access to the setter.
   ///     }
   ///
-  AccessSemantics computeSuperSemantics(Spannable node,
-                                        Selector selector,
-                                        {Name alternateName}) {
+  AccessSemantics computeSuperAccessSemanticsForSelector(
+      Spannable node,
+      Selector selector,
+      {Name alternateName}) {
+
     Name name = selector.memberName;
     // TODO(johnniwinther): Ensure correct behavior if currentClass is a
     // patch.
     Element target = currentClass.lookupSuperByName(name);
     // [target] may be null which means invoking noSuchMethod on super.
     if (target == null) {
       Element error = reportAndCreateErroneousElement(
           node, name.text, MessageKind.NO_SUCH_SUPER_MEMBER,
           {'className': currentClass.name, 'memberName': name});
       if (alternateName != null) {
         target = currentClass.lookupSuperByName(alternateName);
       }
       if (target == null) {
         // If a setter wasn't resolved, use the [ErroneousElement].
         target = error;
       }
       // We still need to register the invocation, because we might
       // call [:super.noSuchMethod:] which calls [JSInvocationMirror._invokeOn].
       registry.registerDynamicInvocation(selector);
       registry.registerSuperNoSuchMethod();
     }
-    return computeSuperAccess(node, target);
+    return computeSuperAccessSemantics(node, target);
   }
 
   /// Resolve [node] as subexpression that is _not_ the prefix of a member
   /// access. For instance `a` in `a + b`, as opposed to `a` in `a.b`.
   ResolutionResult visitExpression(Node node) {
     bool oldSendIsMemberAccess = sendIsMemberAccess;
     sendIsMemberAccess = false;
     ResolutionResult result = visit(node);
     sendIsMemberAccess = oldSendIsMemberAccess;
     return result;
@@ skipping 57 matching lines @@
   ResolutionResult handleUserDefinableUnary(Send node, UnaryOperator operator) {
     Node expression = node.receiver;
     Selector selector = operator.selector;
     // TODO(johnniwinther): Remove this when all information goes through the
     // [SendStructure].
     registry.setSelector(node, selector);
 
     AccessSemantics semantics;
     if (node.isSuperCall) {
       if (checkSuperAccess(node)) {
-        semantics = computeSuperSemantics(node, selector);
+        semantics = computeSuperAccessSemanticsForSelector(node, selector);
         // TODO(johnniwinther): Add information to [AccessSemantics] about
         // whether it is erroneous.
         if (semantics.kind == AccessKind.SUPER_METHOD) {
           registry.registerStaticUse(semantics.element.declaration);
         }
         // TODO(johnniwinther): Remove this when all information goes through
         // the [SendStructure].
         registry.useElement(node, semantics.element);
       }
     } else {
@@ skipping 78 matching lines @@
       selector = new Selector.index();
     } else {
       selector = new Selector.binaryOperator(operator.selectorName);
     }
     // TODO(johnniwinther): Remove this when all information goes through the
     // [SendStructure].
     registry.setSelector(node, selector);
 
     if (node.isSuperCall) {
       if (checkSuperAccess(node)) {
-        semantics = computeSuperSemantics(node, selector);
+        semantics = computeSuperAccessSemanticsForSelector(node, selector);
         // TODO(johnniwinther): Add information to [AccessSemantics] about
         // whether it is erroneous.
         if (semantics.kind == AccessKind.SUPER_METHOD) {
           registry.registerStaticUse(semantics.element.declaration);
         }
         // TODO(johnniwinther): Remove this when all information goes through
         // the [SendStructure].
         registry.useElement(node, semantics.element);
       }
     } else {
@@ skipping 143 matching lines @@
     Element target;
     Selector selector;
     CallStructure callStructure = CallStructure.NO_ARGS;
     if (node.isCall) {
       callStructure = resolveArguments(node.argumentsNode);
       selector = new Selector(SelectorKind.CALL, name, callStructure);
     } else {
       selector = new Selector(SelectorKind.GETTER, name, callStructure);
     }
     if (checkSuperAccess(node)) {
-      AccessSemantics semantics = computeSuperSemantics(
+      AccessSemantics semantics = computeSuperAccessSemanticsForSelector(
           node, selector, alternateName: name.setter);
       if (node.isCall) {
         bool isIncompatibleInvoke = false;
         switch (semantics.kind) {
           case AccessKind.SUPER_METHOD:
             MethodElementX superMethod = semantics.element;
             superMethod.computeSignature(compiler);
             if (!callStructure.signatureApplies(superMethod)) {
               registry.registerThrowNoSuchMethod();
               registry.registerDynamicInvocation(selector);
               registry.registerSuperNoSuchMethod();
               isIncompatibleInvoke = true;
             } else {
               registry.registerStaticInvocation(semantics.element);
             }
             break;
           case AccessKind.SUPER_FIELD:
+          case AccessKind.SUPER_FINAL_FIELD:
           case AccessKind.SUPER_GETTER:
             registry.registerStaticUse(semantics.element);
             selector = callStructure.callSelector;
             registry.registerDynamicInvocation(selector);
             break;
           case AccessKind.SUPER_SETTER:
           case AccessKind.UNRESOLVED_SUPER:
             // NoSuchMethod registered in [computeSuperSemantics].
             break;
           default:
             internalError(node, "Unexpected super property access $semantics.");
             break;
         }
         registry.registerSendStructure(node,
             isIncompatibleInvoke
                 ? new IncompatibleInvokeStructure(semantics, selector)
                 : new InvokeStructure(semantics, selector));
       } else {
         switch (semantics.kind) {
           case AccessKind.SUPER_METHOD:
             // TODO(johnniwinther): Method this should be registered as a
             // closurization.
             registry.registerStaticUse(semantics.element);
             break;
           case AccessKind.SUPER_FIELD:
+          case AccessKind.SUPER_FINAL_FIELD:
           case AccessKind.SUPER_GETTER:
             registry.registerStaticUse(semantics.element);
             break;
           case AccessKind.SUPER_SETTER:
           case AccessKind.UNRESOLVED_SUPER:
             // NoSuchMethod registered in [computeSuperSemantics].
             break;
           default:
             internalError(node, "Unexpected super property access $semantics.");
             break;
@@ skipping 89 matching lines @@
     // TODO(johnniwinther): Handle remaining qualified sends.
     return oldVisitSend(node);
   }
 
   /// Handle access unresolved access to [name] in a non-instance context.
   ResolutionResult handleUnresolvedAccess(
         Send node, Name name, Element element) {
     // TODO(johnniwinther): Support unresolved top level access as an
     // [AccessSemantics].
     AccessSemantics accessSemantics = new StaticAccess.unresolved(element);
+    return handleErroneousAccess(node, name, element, accessSemantics);
+  }
+
+  /// Handle erroneous access of [element] of the given [accessSemantics].
+  ResolutionResult handleErroneousAccess(
+      Send node, Name name, Element element, AccessSemantics accessSemantics) {
     SendStructure sendStructure;
     Selector selector;
     if (node.isCall) {
       CallStructure callStructure = resolveArguments(node.argumentsNode);
       selector = new Selector(SelectorKind.CALL, name, callStructure);
       registry.registerDynamicInvocation(selector);
       sendStructure = new InvokeStructure(accessSemantics, selector);
     } else {
       assert(invariant(node, node.isPropertyAccess));
       selector = new Selector(
           SelectorKind.GETTER, name, CallStructure.NO_ARGS);
       registry.registerDynamicGetter(selector);
       sendStructure = new GetStructure(accessSemantics, selector);
     }
     // TODO(johnniwinther): Remove this when all information goes through
     // the [SendStructure].
     registry.setSelector(node, selector);
     registry.useElement(node, element);
     registry.registerSendStructure(node, sendStructure);
     return null;
   }
 
+  /// Handle access to an ambiguous element, that is, a name imported twice.
+  ResolutionResult handleAmbiguousSend(
+      Send node,
+      Name name,
+      AmbiguousElement element) {
+
+    compiler.reportError(
+        node, element.messageKind, element.messageArguments);
+    element.diagnose(enclosingElement, compiler);
+
+    ErroneousElement error = new ErroneousElementX(
+        element.messageKind,
+        element.messageArguments,
+        name.text,
+        enclosingElement);
+
+    // TODO(johnniwinther): Support ambiguous access as an [AccessSemantics].
+    AccessSemantics accessSemantics = new StaticAccess.unresolved(error);
+    return handleErroneousAccess(node, name, error, accessSemantics);
+  }
+
+  /// Handle access of an instance [member] from a non-instance context.
+  ResolutionResult handleStaticInstanceSend(
+      Send node, Name name, MemberElement member) {
+    compiler.reportError(
+        node, MessageKind.NO_INSTANCE_AVAILABLE, {'name': member.name});
+    ErroneousElement error = new ErroneousElementX(
+        MessageKind.NO_INSTANCE_AVAILABLE,
+        {'name': name},
+        name.text,
+        enclosingElement);
+
+    // TODO(johnniwinther): Support static instance access as an
+    // [AccessSemantics].
+    AccessSemantics accessSemantics = new StaticAccess.unresolved(error);
+    return handleErroneousAccess(node, name, error, accessSemantics);
+  }
+
+  /// Handle access of a parameter, local variable or local function.
+  ResolutionResult handleLocalAccess(Send node, Name name, Element element) {
+    AccessSemantics semantics = computeLocalAccessSemantics(node, element);
+    Selector selector;
+    CallStructure callStructure = CallStructure.NO_ARGS;
+    if (node.isCall) {
+      callStructure = resolveArguments(node.argumentsNode);
+      selector = new Selector(SelectorKind.CALL, name, callStructure);
+    } else {
+      selector = new Selector(SelectorKind.GETTER, name, callStructure);
+    }
+    if (node.isCall) {
+      bool isIncompatibleInvoke = false;
+      switch (semantics.kind) {
+        case AccessKind.LOCAL_FUNCTION:
+          LocalFunctionElementX function = semantics.element;
+          function.computeSignature(compiler);
+          if (!callStructure.signatureApplies(function)) {
+            registry.registerThrowNoSuchMethod();
+            registry.registerDynamicInvocation(selector);
+            isIncompatibleInvoke = true;
+          }
+          break;
+        case AccessKind.PARAMETER:
+        case AccessKind.FINAL_PARAMETER:
+        case AccessKind.LOCAL_VARIABLE:
+        case AccessKind.FINAL_LOCAL_VARIABLE:
+          selector = callStructure.callSelector;
+          registry.registerDynamicInvocation(selector);
+          break;
+        default:
+          internalError(node,
+              "Unexpected local access $semantics.");
+          break;
+      }
+      registry.registerSendStructure(node,
+          isIncompatibleInvoke
+              ? new IncompatibleInvokeStructure(semantics, selector)
+              : new InvokeStructure(semantics, selector));
+    } else {
+      registry.registerSendStructure(node,
+          new GetStructure(semantics, selector));
+    }
+
+    // TODO(johnniwinther): Remove these when all information goes through
+    // the [SendStructure].
+    registry.useElement(node, element);
+    registry.setSelector(node, selector);
+
+    registerPotentialAccessInClosure(node, element);
+
+    return node.isPropertyAccess ? new ElementResult(element) : null;
+  }
+
+  /// Handle access of a static or top level [element].
+  ResolutionResult handleStaticOrTopLevelAccess(
+        Send node, Name name, Element element) {
+
+    if (name.text == 'sync') {
+      reportHere(compiler, node, 'handleStaticOrTopLevelAccess:$element (${element.isErroneous})');

[karlklose, 2015/06/08 09:05:30]

Debug code?

[Johnni Winther, 2015/06/08 09:36:14]

Yes! Removed.

+    }
+    if (element.isAbstractField) {
+      AbstractFieldElement abstractField = element;
+      if (abstractField.getter != null) {
+        element = abstractField.getter;
+      } else {
+        element = abstractField.setter;
+      }
+    }
+
+    Selector selector;
+    CallStructure callStructure = CallStructure.NO_ARGS;
+    if (node.isCall) {
+      callStructure = resolveArguments(node.argumentsNode);
+      selector = new Selector(SelectorKind.CALL, name, callStructure);
+    } else {
+      selector = new Selector(SelectorKind.GETTER, name, callStructure);
+    }
+    AccessSemantics semantics =
+        computeStaticOrTopLevelAccessSemantics(node, element);
+    if (node.isCall) {
+      bool isIncompatibleInvoke = false;
+      switch (semantics.kind) {
+        case AccessKind.STATIC_METHOD:
+        case AccessKind.TOPLEVEL_METHOD:
+          MethodElementX method = semantics.element;
+          method.computeSignature(compiler);
+          if (!callStructure.signatureApplies(method)) {
+            registry.registerThrowNoSuchMethod();
+            registry.registerDynamicInvocation(selector);
+            isIncompatibleInvoke = true;
+          } else {
+            registry.registerStaticUse(semantics.element);
+            handleForeignCall(node, semantics.element, selector);
+          }
+          break;
+        case AccessKind.STATIC_FIELD:
+        case AccessKind.FINAL_STATIC_FIELD:
+        case AccessKind.STATIC_GETTER:
+        case AccessKind.TOPLEVEL_FIELD:
+        case AccessKind.FINAL_TOPLEVEL_FIELD:
+        case AccessKind.TOPLEVEL_GETTER:
+          registry.registerStaticUse(semantics.element);
+          selector = callStructure.callSelector;
+          registry.registerDynamicInvocation(selector);
+          break;
+        case AccessKind.STATIC_SETTER:
+        case AccessKind.TOPLEVEL_SETTER:
+        case AccessKind.UNRESOLVED:
+          registry.registerThrowNoSuchMethod();
+          element = reportAndCreateErroneousElement(
+              node.selector, name.text,
+              MessageKind.CANNOT_RESOLVE_GETTER, const {});
+          break;
+        default:
+          internalError(node,
+              "Unexpected statically resolved access $semantics.");
+          break;
+      }
+      registry.registerSendStructure(node,
+          isIncompatibleInvoke
+              ? new IncompatibleInvokeStructure(semantics, selector)
+              : new InvokeStructure(semantics, selector));
+    } else {
+      switch (semantics.kind) {
+        case AccessKind.STATIC_METHOD:
+        case AccessKind.TOPLEVEL_METHOD:
+          // TODO(johnniwinther): Method this should be registered as a
+          // closurization.
+          registry.registerStaticUse(semantics.element);
+          registry.registerGetOfStaticFunction(semantics.element);
+          break;
+        case AccessKind.STATIC_FIELD:
+        case AccessKind.FINAL_STATIC_FIELD:
+        case AccessKind.STATIC_GETTER:
+        case AccessKind.TOPLEVEL_FIELD:
+        case AccessKind.FINAL_TOPLEVEL_FIELD:
+        case AccessKind.TOPLEVEL_GETTER:
+          registry.registerStaticUse(semantics.element);
+          break;
+        case AccessKind.STATIC_SETTER:
+        case AccessKind.TOPLEVEL_SETTER:
+        case AccessKind.UNRESOLVED:
+          registry.registerThrowNoSuchMethod();
+          element = reportAndCreateErroneousElement(
+              node.selector, name.text,
+              MessageKind.CANNOT_RESOLVE_GETTER, const {});
+          break;
+        default:
+          internalError(node,
+              "Unexpected statically resolved access $semantics.");
+          break;
+      }
+      registry.registerSendStructure(node,
+          new GetStructure(semantics, selector));
+    }
+
+    // TODO(johnniwinther): Remove these when all information goes through
+    // the [SendStructure].
+    registry.useElement(node, element);
+    registry.setSelector(node, selector);
+
+    return node.isPropertyAccess ? new ElementResult(element) : null;
+  }
+
+  /// Handle access to resolved [element].
+  ResolutionResult handleResolvedSend(Send node, Name name, Element element) {
+    if (element.isAmbiguous) {
+      return handleAmbiguousSend(node, name, element);
+    }
+    if (element.isErroneous) {
+      // This handles elements with parser errors.
+      // TODO(johnniwinther): Elements with parse error should not set
+      // [isErroneous] to `true`.
+      assert(invariant(node, element is! ErroneousElement,
+          message: "Unexpected erroneous element $element."));
+      return handleErroneousAccess(node, name, element,
+          new StaticAccess.unresolved(element));
+    }
+    if (element.isInstanceMember) {
+      if (inInstanceContext) {
+        // TODO(johnniwinther): Maybe use the found [element].
+        return handleThisPropertyAccess(node, name);
+      } else {
+        return handleStaticInstanceSend(node, name, element);
+      }
+    }
+    if (element.isClass || element.isTypedef) {
+      return oldVisitSend(node);
+    } else if (element.isTypeVariable) {
+      return oldVisitSend(node);
+    } else if (element.isPrefix) {
+      return oldVisitSend(node);
+    } else if (element.isLocal) {
+      return handleLocalAccess(node, name, element);
+    } else if (element.isStatic || element.isTopLevel) {
+      return handleStaticOrTopLevelAccess(node, name, element);
+    }
+    return internalError(node, "Unexpected resolved send: $element");
+  }
+
   /// Handle an unqualified [Send], that is where the `node.receiver` is null,
   /// like `a`, `a()`, `this()`, `assert()`, and `(){}()`.
   ResolutionResult handleUnqualifiedSend(Send node) {
     Identifier selector = node.selector.asIdentifier();
     if (selector == null) {
       // `(){}()` and `(foo)()`.
       return handleExpressionInvoke(node);
     }
     String text = selector.source;
     if (text == 'assert') {
@@ skipping 12 matching lines @@
     Element element = lookupInScope(compiler, node, scope, text);
     if (element == null) {
       if (inInstanceContext) {
         // Implicitly `this.name`.
         return handleThisPropertyAccess(node, name);
       } else {
         // Create [ErroneousElement] for unresolved access.
         ErroneousElement error = reportCannotResolve(node, text);
         return handleUnresolvedAccess(node, name, error);
       }
+    } else {
+      return handleResolvedSend(node, name, element);
     }
-    return oldVisitSend(node);
   }
 
   ResolutionResult visitSend(Send node) {
     if (node.isOperator) {
+      // `a && b`, `a + b`, `-a`, or `a is T`.
       return handleOperatorSend(node);
     } else if (node.receiver != null) {
+      // `a.b`.
       return handleQualifiedSend(node);
     } else {
+      // `a`.
       return handleUnqualifiedSend(node);
     }
-    return oldVisitSend(node);
+  }
+
+  /// Regigster read access of [target] inside a closure.
+  void registerPotentialAccessInClosure(Send node, Element target) {
+    if (isPotentiallyMutableTarget(target)) {
+      if (enclosingElement != target.enclosingElement) {
+        for (Node scope in promotionScope) {
+          registry.setAccessedByClosureIn(scope, target, node);
+        }
+      }
+    }
   }
 
   ResolutionResult oldVisitSend(Send node) {
     bool oldSendIsMemberAccess = sendIsMemberAccess;
     sendIsMemberAccess = node.isPropertyAccess || node.isCall;
 
     ResolutionResult result = resolveSend(node);
     sendIsMemberAccess = oldSendIsMemberAccess;
 
     Element target = result != null ? result.element : null;
@@ skipping 27 matching lines @@
           compiler.reportError(node,
               MessageKind.TYPE_VARIABLE_WITHIN_STATIC_MEMBER,
               {'typeVariableName': node.selector});
         }
         registry.registerClassUsingVariableExpression(cls);
         registry.registerTypeVariableExpression();
         registerTypeLiteralAccess(node, target);
       } else if (target.impliesType && (!sendIsMemberAccess || node.isCall)) {
         registerTypeLiteralAccess(node, target);
       }
-      if (isPotentiallyMutableTarget(target)) {
-        if (enclosingElement != target.enclosingElement) {
-          for (Node scope in promotionScope) {
-            registry.setAccessedByClosureIn(scope, target, node);
-          }
-        }
-      }
+      registerPotentialAccessInClosure(node, target);
     }
 
     bool resolvedArguments = false;
     resolveArguments(node.argumentsNode);
 
     // If the selector is null, it means that we will not be generating
     // code for this as a send.
     Selector selector = registry.getSelector(node);
     if (selector == null) return null;
 
@@ skipping 17 matching lines @@
           function.computeSignature(compiler);
         }
         if (!selector.applies(target, compiler.world)) {
           registry.registerThrowNoSuchMethod();
           if (node.isSuperCall) {
             internalError(node, "Unexpected super call $node");
           }
         }
       }
 
-      if (target != null && compiler.backend.isForeign(target)) {
-        if (selector.name == 'JS') {
-          registry.registerJsCall(node, this);
-        } else if (selector.name == 'JS_EMBEDDED_GLOBAL') {
-          registry.registerJsEmbeddedGlobalCall(node, this);
-        } else if (selector.name == 'JS_BUILTIN') {
-          registry.registerJsBuiltinCall(node, this);
-        } else if (selector.name == 'JS_INTERCEPTOR_CONSTANT') {
-          if (!node.argumentsNode.isEmpty) {
-            Node argument = node.argumentsNode.nodes.head;
-            if (argumentsToJsInterceptorConstant == null) {
-              argumentsToJsInterceptorConstant = new Set<Node>();
-            }
-            argumentsToJsInterceptorConstant.add(argument);
-          }
-        }
-      }
+      handleForeignCall(node, target, selector);
     }
 
     registry.useElement(node, target);
     registerSend(selector, target);
     if (node.isPropertyAccess && Elements.isStaticOrTopLevelFunction(target)) {
       registry.registerGetOfStaticFunction(target.declaration);
     }
     return node.isPropertyAccess ? new ElementResult(target) : null;
   }
 
+  // TODO(johnniwinther): Move this to the backend resolution callbacks.
+  void handleForeignCall(Send node, Element target, Selector selector) {
+    if (target != null && compiler.backend.isForeign(target)) {
+      if (selector.name == 'JS') {
+        registry.registerJsCall(node, this);
+      } else if (selector.name == 'JS_EMBEDDED_GLOBAL') {
+        registry.registerJsEmbeddedGlobalCall(node, this);
+      } else if (selector.name == 'JS_BUILTIN') {
+        registry.registerJsBuiltinCall(node, this);
+      } else if (selector.name == 'JS_INTERCEPTOR_CONSTANT') {
+        if (!node.argumentsNode.isEmpty) {
+          Node argument = node.argumentsNode.nodes.head;
+          if (argumentsToJsInterceptorConstant == null) {
+            argumentsToJsInterceptorConstant = new Set<Node>();
+          }
+          argumentsToJsInterceptorConstant.add(argument);
+        }
+      }
+    }
+  }
+
   /// Callback for native enqueuer to parse a type.  Returns [:null:] on error.
   DartType resolveTypeFromString(Node node, String typeName) {
     Element element = lookupInScope(compiler, node, scope, typeName);
     if (element == null) return null;
     if (element is! ClassElement) return null;
     ClassElement cls = element;
     cls.ensureResolved(compiler);
     return cls.computeType(compiler);
   }
 
@@ skipping 1091 matching lines @@
   visitTypedef(Typedef node) {
     internalError(node, 'typedef');
   }
 }
 
 /// Looks up [name] in [scope] and unwraps the result.
 Element lookupInScope(Compiler compiler, Node node,
                       Scope scope, String name) {
   return Elements.unwrap(scope.lookup(name), compiler, node);
 }