Begin separating API and local element builders.

pkg/analyzer/lib/src/dart/element/builder.dart

Index: pkg/analyzer/lib/src/dart/element/builder.dart
diff --git a/pkg/analyzer/lib/src/dart/element/builder.dart b/pkg/analyzer/lib/src/dart/element/builder.dart
index 85a1ff6eab5e7ab3778c44d6677e4c0f96f51f9d..7505ad7a72f7338e7819b48e1af66f578d195613 100644
--- a/pkg/analyzer/lib/src/dart/element/builder.dart
+++ b/pkg/analyzer/lib/src/dart/element/builder.dart
@@ -23,434 +23,118 @@ import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 
 /**
- * A `CompilationUnitBuilder` builds an element model for a single compilation
- * unit.
- */
-class CompilationUnitBuilder {
-  /**
-   * Build the compilation unit element for the given [source] based on the
-   * compilation [unit] associated with the source. Throw an AnalysisException
-   * if the element could not be built.  [librarySource] is the source for the
-   * containing library.
-   */
-  CompilationUnitElementImpl buildCompilationUnit(
-      Source source, CompilationUnit unit, Source librarySource) {
-    return PerformanceStatistics.resolve.makeCurrentWhile(() {
-      if (unit == null) {
-        return null;
-      }
-      ElementHolder holder = new ElementHolder();
-      CompilationUnitElementImpl element =
-          new CompilationUnitElementImpl(source.shortName);
-      ElementBuilder builder = new ElementBuilder(holder, element);
-      unit.accept(builder);
-      element.accessors = holder.accessors;
-      element.enums = holder.enums;
-      element.functions = holder.functions;
-      element.source = source;
-      element.librarySource = librarySource;
-      element.typeAliases = holder.typeAliases;
-      element.types = holder.types;
-      element.topLevelVariables = holder.topLevelVariables;
-      unit.element = element;
-      holder.validate();
-      return element;
-    });
-  }
-}
-
-/**
- * Instances of the class `DirectiveElementBuilder` build elements for top
- * level library directives.
+ * Instances of the class `ApiElementBuilder` traverse an AST structure and
+ * build elements outside of function bodies and initializers.
  */
-class DirectiveElementBuilder extends SimpleAstVisitor<Object> {
-  /**
-   * The analysis context within which directive elements are being built.
-   */
-  final AnalysisContext context;
-
-  /**
-   * The library element for which directive elements are being built.
-   */
-  final LibraryElementImpl libraryElement;
-
-  /**
-   * Map from sources referenced by this library to their modification times.
-   */
-  final Map<Source, int> sourceModificationTimeMap;
-
-  /**
-   * Map from sources imported by this library to their corresponding library
-   * elements.
-   */
-  final Map<Source, LibraryElement> importLibraryMap;
-
-  /**
-   * Map from sources imported by this library to their corresponding source
-   * kinds.
-   */
-  final Map<Source, SourceKind> importSourceKindMap;
-
-  /**
-   * Map from sources exported by this library to their corresponding library
-   * elements.
-   */
-  final Map<Source, LibraryElement> exportLibraryMap;
-
-  /**
-   * Map from sources exported by this library to their corresponding source
-   * kinds.
-   */
-  final Map<Source, SourceKind> exportSourceKindMap;
-
+class ApiElementBuilder extends _BaseElementBuilder {
   /**
-   * The [ImportElement]s created so far.
+   * A flag indicating whether a variable declaration is within the body of a method or function.
    */
-  final List<ImportElement> imports = <ImportElement>[];
+  bool _inFunction = false;
 
   /**
-   * The [ExportElement]s created so far.
+   * A table mapping field names to field elements for the fields defined in the current class, or
+   * `null` if we are not in the scope of a class.
    */
-  final List<ExportElement> exports = <ExportElement>[];
+  HashMap<String, FieldElement> _fieldMap;
 
   /**
-   * The errors found while building directive elements.
+   * Initialize a newly created element builder to build the elements for a
+   * compilation unit. The [initialHolder] is the element holder to which the
+   * children of the visited compilation unit node will be added.
    */
-  final List<AnalysisError> errors = <AnalysisError>[];
+  ApiElementBuilder(ElementHolder initialHolder,
+      CompilationUnitElementImpl compilationUnitElement)
+      : super(initialHolder, compilationUnitElement);
 
   /**
-   * Map from prefix names to their corresponding elements.
+   * Prepares for incremental resolution of a function body.
    */
-  final HashMap<String, PrefixElementImpl> nameToPrefixMap =
-      new HashMap<String, PrefixElementImpl>();
+  void initForFunctionBodyIncrementalResolution() {
+    _inFunction = true;
+  }
 
-  /**
-   * Indicates whether an explicit import of `dart:core` has been found.
-   */
-  bool explicitlyImportsCore = false;
+  @override
+  Object visitAnnotation(Annotation node) {
+    // Although it isn't valid to do so because closures are not constant
+    // expressions, it's possible for one of the arguments to the constructor to
+    // contain a closure. Wrapping the processing of the annotation this way
+    // prevents these closures from being added to the list of functions in the
+    // annotated declaration.
+    ElementHolder holder = new ElementHolder();
+    ElementHolder previousHolder = _currentHolder;
+    _currentHolder = holder;
+    try {
+      super.visitAnnotation(node);
+    } finally {
+      _currentHolder = previousHolder;
+    }
+    return null;
+  }
 
-  DirectiveElementBuilder(
-      this.context,
-      this.libraryElement,
-      this.sourceModificationTimeMap,
-      this.importLibraryMap,
-      this.importSourceKindMap,
-      this.exportLibraryMap,
-      this.exportSourceKindMap);
+  @override
+  Object visitBlockFunctionBody(BlockFunctionBody node) {
+    return null;
+  }
 
   @override
-  Object visitCompilationUnit(CompilationUnit node) {
+  Object visitClassDeclaration(ClassDeclaration node) {
+    ElementHolder holder = new ElementHolder();
     //
-    // Resolve directives.
+    // Process field declarations before constructors and methods so that field
+    // formal parameters can be correctly resolved to their fields.
     //
-    for (Directive directive in node.directives) {
-      directive.accept(this);
+    ElementHolder previousHolder = _currentHolder;
+    _currentHolder = holder;
+    try {
+      List<ClassMember> nonFields = new List<ClassMember>();
+      node.visitChildren(
+          new _ElementBuilder_visitClassDeclaration(this, nonFields));
+      _buildFieldMap(holder.fieldsWithoutFlushing);
+      int count = nonFields.length;
+      for (int i = 0; i < count; i++) {
+        nonFields[i].accept(this);
+      }
+    } finally {
+      _currentHolder = previousHolder;
     }
-    //
-    // Ensure "dart:core" import.
-    //
-    Source librarySource = libraryElement.source;
-    Source coreLibrarySource = context.sourceFactory.forUri(DartSdk.DART_CORE);
-    if (!explicitlyImportsCore && coreLibrarySource != librarySource) {
-      ImportElementImpl importElement = new ImportElementImpl(-1);
-      importElement.importedLibrary = importLibraryMap[coreLibrarySource];
-      importElement.synthetic = true;
-      imports.add(importElement);
+    SimpleIdentifier className = node.name;
+    ClassElementImpl element = new ClassElementImpl.forNode(className);
+    _setCodeRange(element, node);
+    element.metadata = _createElementAnnotations(node.metadata);
+    element.typeParameters = holder.typeParameters;
+    setElementDocumentationComment(element, node);
+    element.abstract = node.isAbstract;
+    element.accessors = holder.accessors;
+    List<ConstructorElement> constructors = holder.constructors;
+    if (constructors.isEmpty) {
+      constructors = _createDefaultConstructors(element);
     }
-    //
-    // Populate the library element.
-    //
-    libraryElement.imports = imports;
-    libraryElement.exports = exports;
+    element.constructors = constructors;
+    element.fields = holder.fields;
+    element.methods = holder.methods;
+    _currentHolder.addType(element);
+    className.staticElement = element;
+    _fieldMap = null;
+    holder.validate();
     return null;
   }
 
   @override
-  Object visitExportDirective(ExportDirective node) {
-    // Remove previous element. (It will remain null if the target is missing.)
-    node.element = null;
-    Source exportedSource = node.selectedSource;
-    int exportedTime = sourceModificationTimeMap[exportedSource] ?? -1;
-    // The exported source will be null if the URI in the export
-    // directive was invalid.
-    LibraryElement exportedLibrary = exportLibraryMap[exportedSource];
-    if (exportedLibrary != null) {
-      ExportElementImpl exportElement = new ExportElementImpl(node.offset);
-      exportElement.metadata = _getElementAnnotations(node.metadata);
-      StringLiteral uriLiteral = node.uri;
-      if (uriLiteral != null) {
-        exportElement.uriOffset = uriLiteral.offset;
-        exportElement.uriEnd = uriLiteral.end;
-      }
-      exportElement.uri = node.selectedUriContent;
-      exportElement.combinators = _buildCombinators(node);
-      exportElement.exportedLibrary = exportedLibrary;
-      setElementDocumentationComment(exportElement, node);
-      node.element = exportElement;
-      exports.add(exportElement);
-      if (exportedTime >= 0 &&
-          exportSourceKindMap[exportedSource] != SourceKind.LIBRARY) {
-        int offset = node.offset;
-        int length = node.length;
-        if (uriLiteral != null) {
-          offset = uriLiteral.offset;
-          length = uriLiteral.length;
-        }
-        errors.add(new AnalysisError(
-            libraryElement.source,
-            offset,
-            length,
-            CompileTimeErrorCode.EXPORT_OF_NON_LIBRARY,
-            [uriLiteral.toSource()]));
-      }
-    }
-    return null;
-  }
-
-  @override
-  Object visitImportDirective(ImportDirective node) {
-    // Remove previous element. (It will remain null if the target is missing.)
-    node.element = null;
-    Source importedSource = node.selectedSource;
-    int importedTime = sourceModificationTimeMap[importedSource] ?? -1;
-    // The imported source will be null if the URI in the import
-    // directive was invalid.
-    LibraryElement importedLibrary = importLibraryMap[importedSource];
-    if (importedLibrary != null) {
-      if (importedLibrary.isDartCore) {
-        explicitlyImportsCore = true;
-      }
-      ImportElementImpl importElement = new ImportElementImpl(node.offset);
-      importElement.metadata = _getElementAnnotations(node.metadata);
-      StringLiteral uriLiteral = node.uri;
-      if (uriLiteral != null) {
-        importElement.uriOffset = uriLiteral.offset;
-        importElement.uriEnd = uriLiteral.end;
-      }
-      importElement.uri = node.selectedUriContent;
-      importElement.deferred = node.deferredKeyword != null;
-      importElement.combinators = _buildCombinators(node);
-      importElement.importedLibrary = importedLibrary;
-      setElementDocumentationComment(importElement, node);
-      SimpleIdentifier prefixNode = node.prefix;
-      if (prefixNode != null) {
-        importElement.prefixOffset = prefixNode.offset;
-        String prefixName = prefixNode.name;
-        PrefixElementImpl prefix = nameToPrefixMap[prefixName];
-        if (prefix == null) {
-          prefix = new PrefixElementImpl.forNode(prefixNode);
-          nameToPrefixMap[prefixName] = prefix;
-        }
-        importElement.prefix = prefix;
-        prefixNode.staticElement = prefix;
-      }
-      node.element = importElement;
-      imports.add(importElement);
-      if (importedTime >= 0 &&
-          importSourceKindMap[importedSource] != SourceKind.LIBRARY) {
-        int offset = node.offset;
-        int length = node.length;
-        if (uriLiteral != null) {
-          offset = uriLiteral.offset;
-          length = uriLiteral.length;
-        }
-        ErrorCode errorCode = importElement.isDeferred
-            ? StaticWarningCode.IMPORT_OF_NON_LIBRARY
-            : CompileTimeErrorCode.IMPORT_OF_NON_LIBRARY;
-        errors.add(new AnalysisError(libraryElement.source, offset, length,
-            errorCode, [uriLiteral.toSource()]));
-      }
-    }
-    return null;
-  }
-
-  @override
-  Object visitLibraryDirective(LibraryDirective node) {
-    (node.element as LibraryElementImpl)?.metadata =
-        _getElementAnnotations(node.metadata);
-    return null;
-  }
-
-  @override
-  Object visitPartDirective(PartDirective node) {
-    (node.element as CompilationUnitElementImpl)?.metadata =
-        _getElementAnnotations(node.metadata);
-    return null;
-  }
-
-  /**
-   * Gather a list of the [ElementAnnotation]s referred to by the [Annotation]s
-   * in [metadata].
-   */
-  List<ElementAnnotation> _getElementAnnotations(
-      NodeList<Annotation> metadata) {
-    if (metadata.isEmpty) {
-      return ElementAnnotation.EMPTY_LIST;
-    }
-    return metadata.map((Annotation a) => a.elementAnnotation).toList();
-  }
-
-  /**
-   * Build the element model representing the combinators declared by
-   * the given [directive].
-   */
-  static List<NamespaceCombinator> _buildCombinators(
-      NamespaceDirective directive) {
-    _NamespaceCombinatorBuilder namespaceCombinatorBuilder =
-        new _NamespaceCombinatorBuilder();
-    for (Combinator combinator in directive.combinators) {
-      combinator.accept(namespaceCombinatorBuilder);
-    }
-    return namespaceCombinatorBuilder.combinators;
-  }
-}
-
-/**
- * Instances of the class `ElementBuilder` traverse an AST structure and build the element
- * model representing the AST structure.
- */
-class ElementBuilder extends RecursiveAstVisitor<Object> {
-  /**
-   * The compilation unit element into which the elements being built will be
-   * stored.
-   */
-  final CompilationUnitElementImpl compilationUnitElement;
-
-  /**
-   * The element holder associated with the element that is currently being built.
-   */
-  ElementHolder _currentHolder;
-
-  /**
-   * A flag indicating whether a variable declaration is within the body of a method or function.
-   */
-  bool _inFunction = false;
-
-  /**
-   * A table mapping field names to field elements for the fields defined in the current class, or
-   * `null` if we are not in the scope of a class.
-   */
-  HashMap<String, FieldElement> _fieldMap;
-
-  /**
-   * Initialize a newly created element builder to build the elements for a
-   * compilation unit. The [initialHolder] is the element holder to which the
-   * children of the visited compilation unit node will be added.
-   */
-  ElementBuilder(ElementHolder initialHolder, this.compilationUnitElement) {
-    _currentHolder = initialHolder;
-  }
-
-  /**
-   * Prepares for incremental resolution of a function body.
-   */
-  void initForFunctionBodyIncrementalResolution() {
-    _inFunction = true;
-  }
-
-  @override
-  Object visitAnnotation(Annotation node) {
-    // Although it isn't valid to do so because closures are not constant
-    // expressions, it's possible for one of the arguments to the constructor to
-    // contain a closure. Wrapping the processing of the annotation this way
-    // prevents these closures from being added to the list of functions in the
-    // annotated declaration.
-    ElementHolder holder = new ElementHolder();
-    ElementHolder previousHolder = _currentHolder;
-    _currentHolder = holder;
-    try {
-      super.visitAnnotation(node);
-    } finally {
-      _currentHolder = previousHolder;
-    }
-    return null;
-  }
-
-  @override
-  Object visitCatchClause(CatchClause node) {
-    SimpleIdentifier exceptionParameter = node.exceptionParameter;
-    if (exceptionParameter != null) {
-      // exception
-      LocalVariableElementImpl exception =
-          new LocalVariableElementImpl.forNode(exceptionParameter);
-      if (node.exceptionType == null) {
-        exception.hasImplicitType = true;
-      }
-      exception.setVisibleRange(node.offset, node.length);
-      _currentHolder.addLocalVariable(exception);
-      exceptionParameter.staticElement = exception;
-      // stack trace
-      SimpleIdentifier stackTraceParameter = node.stackTraceParameter;
-      if (stackTraceParameter != null) {
-        LocalVariableElementImpl stackTrace =
-            new LocalVariableElementImpl.forNode(stackTraceParameter);
-        _setCodeRange(stackTrace, stackTraceParameter);
-        stackTrace.setVisibleRange(node.offset, node.length);
-        _currentHolder.addLocalVariable(stackTrace);
-        stackTraceParameter.staticElement = stackTrace;
-      }
-    }
-    return super.visitCatchClause(node);
-  }
-
-  @override
-  Object visitClassDeclaration(ClassDeclaration node) {
-    ElementHolder holder = new ElementHolder();
-    //
-    // Process field declarations before constructors and methods so that field
-    // formal parameters can be correctly resolved to their fields.
-    //
-    ElementHolder previousHolder = _currentHolder;
-    _currentHolder = holder;
-    try {
-      List<ClassMember> nonFields = new List<ClassMember>();
-      node.visitChildren(
-          new _ElementBuilder_visitClassDeclaration(this, nonFields));
-      _buildFieldMap(holder.fieldsWithoutFlushing);
-      int count = nonFields.length;
-      for (int i = 0; i < count; i++) {
-        nonFields[i].accept(this);
-      }
-    } finally {
-      _currentHolder = previousHolder;
-    }
-    SimpleIdentifier className = node.name;
-    ClassElementImpl element = new ClassElementImpl.forNode(className);
-    _setCodeRange(element, node);
-    element.metadata = _createElementAnnotations(node.metadata);
-    element.typeParameters = holder.typeParameters;
-    setElementDocumentationComment(element, node);
-    element.abstract = node.isAbstract;
-    element.accessors = holder.accessors;
-    List<ConstructorElement> constructors = holder.constructors;
-    if (constructors.isEmpty) {
-      constructors = _createDefaultConstructors(element);
-    }
-    element.constructors = constructors;
-    element.fields = holder.fields;
-    element.methods = holder.methods;
-    _currentHolder.addType(element);
-    className.staticElement = element;
-    _fieldMap = null;
-    holder.validate();
-    return null;
-  }
-
-  @override
-  Object visitClassTypeAlias(ClassTypeAlias node) {
-    ElementHolder holder = new ElementHolder();
-    _visitChildren(holder, node);
-    SimpleIdentifier className = node.name;
-    ClassElementImpl element = new ClassElementImpl.forNode(className);
-    _setCodeRange(element, node);
-    element.metadata = _createElementAnnotations(node.metadata);
-    element.abstract = node.abstractKeyword != null;
-    element.mixinApplication = true;
-    element.typeParameters = holder.typeParameters;
-    setElementDocumentationComment(element, node);
-    _currentHolder.addType(element);
-    className.staticElement = element;
-    holder.validate();
+  Object visitClassTypeAlias(ClassTypeAlias node) {
+    ElementHolder holder = new ElementHolder();
+    _visitChildren(holder, node);
+    SimpleIdentifier className = node.name;
+    ClassElementImpl element = new ClassElementImpl.forNode(className);
+    _setCodeRange(element, node);
+    element.metadata = _createElementAnnotations(node.metadata);
+    element.abstract = node.abstractKeyword != null;
+    element.mixinApplication = true;
+    element.typeParameters = holder.typeParameters;
+    setElementDocumentationComment(element, node);
+    _currentHolder.addType(element);
+    className.staticElement = element;
+    holder.validate();
     return null;
   }
 
@@ -514,75 +198,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
-  Object visitDeclaredIdentifier(DeclaredIdentifier node) {
-    SimpleIdentifier variableName = node.identifier;
-    LocalVariableElementImpl element =
-        new LocalVariableElementImpl.forNode(variableName);
-    _setCodeRange(element, node);
-    element.metadata = _createElementAnnotations(node.metadata);
-    ForEachStatement statement = node.parent as ForEachStatement;
-    element.setVisibleRange(statement.offset, statement.length);
-    element.const3 = node.isConst;
-    element.final2 = node.isFinal;
-    if (node.type == null) {
-      element.hasImplicitType = true;
-    }
-    _currentHolder.addLocalVariable(element);
-    variableName.staticElement = element;
-    return super.visitDeclaredIdentifier(node);
-  }
-
-  @override
-  Object visitDefaultFormalParameter(DefaultFormalParameter node) {
-    ElementHolder holder = new ElementHolder();
-    NormalFormalParameter normalParameter = node.parameter;
-    SimpleIdentifier parameterName = normalParameter.identifier;
-    ParameterElementImpl parameter;
-    if (normalParameter is FieldFormalParameter) {
-      parameter =
-          new DefaultFieldFormalParameterElementImpl.forNode(parameterName);
-      FieldElement field =
-          _fieldMap == null ? null : _fieldMap[parameterName.name];
-      if (field != null) {
-        (parameter as DefaultFieldFormalParameterElementImpl).field = field;
-      }
-    } else {
-      parameter = new DefaultParameterElementImpl.forNode(parameterName);
-    }
-    _setCodeRange(parameter, node);
-    parameter.const3 = node.isConst;
-    parameter.final2 = node.isFinal;
-    parameter.parameterKind = node.kind;
-    // set initializer, default value range
-    Expression defaultValue = node.defaultValue;
-    if (defaultValue != null) {
-      _visit(holder, defaultValue);
-      FunctionElementImpl initializer =
-          new FunctionElementImpl.forOffset(defaultValue.beginToken.offset);
-      initializer.hasImplicitReturnType = true;
-      initializer.functions = holder.functions;
-      initializer.labels = holder.labels;
-      initializer.localVariables = holder.localVariables;
-      initializer.parameters = holder.parameters;
-      initializer.synthetic = true;
-      initializer.type = new FunctionTypeImpl(initializer);
-      parameter.initializer = initializer;
-      parameter.defaultValueCode = defaultValue.toSource();
-    }
-    // visible range
-    _setParameterVisibleRange(node, parameter);
-    if (normalParameter is SimpleFormalParameter &&
-        normalParameter.type == null) {
-      parameter.hasImplicitType = true;
-    }
-    _currentHolder.addParameter(parameter);
-    parameterName.staticElement = parameter;
-    normalParameter.accept(this);
-    holder.validate();
-    return null;
-  }
-
-  @override
   Object visitEnumDeclaration(EnumDeclaration node) {
     SimpleIdentifier enumName = node.name;
     EnumElementImpl enumElement = new EnumElementImpl.forNode(enumName);
@@ -625,6 +240,11 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
+  Object visitExpressionFunctionBody(ExpressionFunctionBody node) {
+    return null;
+  }
+
+  @override
   Object visitFieldFormalParameter(FieldFormalParameter node) {
     if (node.parent is! DefaultFormalParameter) {
       SimpleIdentifier parameterName = node.identifier;
@@ -851,32 +471,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
-  Object visitFunctionTypedFormalParameter(FunctionTypedFormalParameter node) {
-    if (node.parent is! DefaultFormalParameter) {
-      SimpleIdentifier parameterName = node.identifier;
-      ParameterElementImpl parameter =
-          new ParameterElementImpl.forNode(parameterName);
-      _setCodeRange(parameter, node);
-      parameter.parameterKind = node.kind;
-      _setParameterVisibleRange(node, parameter);
-      _currentHolder.addParameter(parameter);
-      parameterName.staticElement = parameter;
-    }
-    //
-    // The children of this parameter include any parameters defined on the type
-    //of this parameter.
-    //
-    ElementHolder holder = new ElementHolder();
-    _visitChildren(holder, node);
-    ParameterElementImpl element = node.element;
-    element.metadata = _createElementAnnotations(node.metadata);
-    element.parameters = holder.parameters;
-    element.typeParameters = holder.typeParameters;
-    holder.validate();
-    return null;
-  }
-
-  @override
   Object visitImportDirective(ImportDirective node) {
     List<ElementAnnotation> annotations =
         _createElementAnnotations(node.metadata);
@@ -885,19 +479,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
-  Object visitLabeledStatement(LabeledStatement node) {
-    bool onSwitchStatement = node.statement is SwitchStatement;
-    for (Label label in node.labels) {
-      SimpleIdentifier labelName = label.label;
-      LabelElementImpl element =
-          new LabelElementImpl.forNode(labelName, onSwitchStatement, false);
-      _currentHolder.addLabel(element);
-      labelName.staticElement = element;
-    }
-    return super.visitLabeledStatement(node);
-  }
-
-  @override
   Object visitLibraryDirective(LibraryDirective node) {
     List<ElementAnnotation> annotations =
         _createElementAnnotations(node.metadata);
@@ -1063,11 +644,792 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
-  Object visitPartDirective(PartDirective node) {
-    List<ElementAnnotation> annotations =
-        _createElementAnnotations(node.metadata);
-    compilationUnitElement.setAnnotations(node.offset, annotations);
-    return super.visitPartDirective(node);
+  Object visitPartDirective(PartDirective node) {
+    List<ElementAnnotation> annotations =
+        _createElementAnnotations(node.metadata);
+    compilationUnitElement.setAnnotations(node.offset, annotations);
+    return super.visitPartDirective(node);
+  }
+
+  @override
+  Object visitVariableDeclaration(VariableDeclaration node) {
+    bool isConst = node.isConst;
+    bool isFinal = node.isFinal;
+    Expression initializerNode = node.initializer;
+    bool hasInitializer = initializerNode != null;
+    VariableDeclarationList varList = node.parent;
+    FieldDeclaration fieldNode =
+        varList.parent is FieldDeclaration ? varList.parent : null;
+    VariableElementImpl element;
+    if (fieldNode != null) {
+      SimpleIdentifier fieldName = node.name;
+      FieldElementImpl field;
+      if ((isConst || isFinal && !fieldNode.isStatic) && hasInitializer) {
+        field = new ConstFieldElementImpl.forNode(fieldName);
+      } else {
+        field = new FieldElementImpl.forNode(fieldName);
+      }
+      element = field;
+      field.static = fieldNode.isStatic;
+      _setCodeRange(element, node);
+      setElementDocumentationComment(element, fieldNode);
+      field.hasImplicitType = varList.type == null;
+      _currentHolder.addField(field);
+      fieldName.staticElement = field;
+    } else {
+      SimpleIdentifier variableName = node.name;
+      TopLevelVariableElementImpl variable;
+      if (isConst && hasInitializer) {
+        variable = new ConstTopLevelVariableElementImpl.forNode(variableName);
+      } else {
+        variable = new TopLevelVariableElementImpl.forNode(variableName);
+      }
+      element = variable;
+      _setCodeRange(element, node);
+      if (varList.parent is TopLevelVariableDeclaration) {
+        setElementDocumentationComment(element, varList.parent);
+      }
+      variable.hasImplicitType = varList.type == null;
+      _currentHolder.addTopLevelVariable(variable);
+      variableName.staticElement = element;
+    }
+    element.const3 = isConst;
+    element.final2 = isFinal;
+    if (element is PropertyInducingElementImpl) {
+      PropertyAccessorElementImpl_ImplicitGetter getter =
+          new PropertyAccessorElementImpl_ImplicitGetter(element);
+      _currentHolder.addAccessor(getter);
+      if (!isConst && !isFinal) {
+        PropertyAccessorElementImpl_ImplicitSetter setter =
+            new PropertyAccessorElementImpl_ImplicitSetter(element);
+        _currentHolder.addAccessor(setter);
+      }
+    }
+    return null;
+  }
+
+  @override
+  Object visitVariableDeclarationList(VariableDeclarationList node) {
+    super.visitVariableDeclarationList(node);
+    AstNode parent = node.parent;
+    List<ElementAnnotation> elementAnnotations;
+    if (parent is FieldDeclaration) {
+      elementAnnotations = _createElementAnnotations(parent.metadata);
+    } else if (parent is TopLevelVariableDeclaration) {
+      elementAnnotations = _createElementAnnotations(parent.metadata);
+    } else {
+      // Local variable declaration
+      elementAnnotations = _createElementAnnotations(node.metadata);
+    }
+    _setVariableDeclarationListAnnotations(node, elementAnnotations);
+    return null;
+  }
+
+  /**
+   * Build the table mapping field names to field elements for the fields defined in the current
+   * class.
+   *
+   * @param fields the field elements defined in the current class
+   */
+  void _buildFieldMap(List<FieldElement> fields) {
+    _fieldMap = new HashMap<String, FieldElement>();
+    int count = fields.length;
+    for (int i = 0; i < count; i++) {
+      FieldElement field = fields[i];
+      _fieldMap[field.name] ??= field;
+    }
+  }
+
+  /**
+   * Creates the [ConstructorElement]s array with the single default constructor element.
+   *
+   * @param interfaceType the interface type for which to create a default constructor
+   * @return the [ConstructorElement]s array with the single default constructor element
+   */
+  List<ConstructorElement> _createDefaultConstructors(
+      ClassElementImpl definingClass) {
+    ConstructorElementImpl constructor =
+        new ConstructorElementImpl.forNode(null);
+    constructor.synthetic = true;
+    constructor.enclosingElement = definingClass;
+    return <ConstructorElement>[constructor];
+  }
+
+  /**
+   * Create the types associated with the given type parameters, setting the type of each type
+   * parameter, and return an array of types corresponding to the given parameters.
+   *
+   * @param typeParameters the type parameters for which types are to be created
+   * @return an array of types corresponding to the given parameters
+   */
+  List<DartType> _createTypeParameterTypes(
+      List<TypeParameterElement> typeParameters) {
+    int typeParameterCount = typeParameters.length;
+    List<DartType> typeArguments = new List<DartType>(typeParameterCount);
+    for (int i = 0; i < typeParameterCount; i++) {
+      TypeParameterElementImpl typeParameter =
+          typeParameters[i] as TypeParameterElementImpl;
+      TypeParameterTypeImpl typeParameterType =
+          new TypeParameterTypeImpl(typeParameter);
+      typeParameter.type = typeParameterType;
+      typeArguments[i] = typeParameterType;
+    }
+    return typeArguments;
+  }
+
+  @override
+  void _setFieldParameterField(FieldFormalParameterElementImpl parameter) {
+    FieldElement field = _fieldMap == null ? null : _fieldMap[parameter.name];
+    if (field != null) {
+      parameter.field = field;
+    }
+  }
+}
+
+/**
+ * A `CompilationUnitBuilder` builds an element model for a single compilation
+ * unit.
+ */
+class CompilationUnitBuilder {
+  /**
+   * Build the compilation unit element for the given [source] based on the
+   * compilation [unit] associated with the source. Throw an AnalysisException
+   * if the element could not be built.  [librarySource] is the source for the
+   * containing library.
+   */
+  CompilationUnitElementImpl buildCompilationUnit(
+      Source source, CompilationUnit unit, Source librarySource) {
+    return PerformanceStatistics.resolve.makeCurrentWhile(() {
+      if (unit == null) {
+        return null;
+      }
+      ElementHolder holder = new ElementHolder();
+      CompilationUnitElementImpl element =
+          new CompilationUnitElementImpl(source.shortName);
+      ElementBuilder builder = new ElementBuilder(holder, element);
+      unit.accept(builder);
+      element.accessors = holder.accessors;
+      element.enums = holder.enums;
+      element.functions = holder.functions;
+      element.source = source;
+      element.librarySource = librarySource;
+      element.typeAliases = holder.typeAliases;
+      element.types = holder.types;
+      element.topLevelVariables = holder.topLevelVariables;
+      unit.element = element;
+      holder.validate();
+      return element;
+    });
+  }
+}
+
+/**
+ * Instances of the class `DirectiveElementBuilder` build elements for top
+ * level library directives.
+ */
+class DirectiveElementBuilder extends SimpleAstVisitor<Object> {
+  /**
+   * The analysis context within which directive elements are being built.
+   */
+  final AnalysisContext context;
+
+  /**
+   * The library element for which directive elements are being built.
+   */
+  final LibraryElementImpl libraryElement;
+
+  /**
+   * Map from sources referenced by this library to their modification times.
+   */
+  final Map<Source, int> sourceModificationTimeMap;
+
+  /**
+   * Map from sources imported by this library to their corresponding library
+   * elements.
+   */
+  final Map<Source, LibraryElement> importLibraryMap;
+
+  /**
+   * Map from sources imported by this library to their corresponding source
+   * kinds.
+   */
+  final Map<Source, SourceKind> importSourceKindMap;
+
+  /**
+   * Map from sources exported by this library to their corresponding library
+   * elements.
+   */
+  final Map<Source, LibraryElement> exportLibraryMap;
+
+  /**
+   * Map from sources exported by this library to their corresponding source
+   * kinds.
+   */
+  final Map<Source, SourceKind> exportSourceKindMap;
+
+  /**
+   * The [ImportElement]s created so far.
+   */
+  final List<ImportElement> imports = <ImportElement>[];
+
+  /**
+   * The [ExportElement]s created so far.
+   */
+  final List<ExportElement> exports = <ExportElement>[];
+
+  /**
+   * The errors found while building directive elements.
+   */
+  final List<AnalysisError> errors = <AnalysisError>[];
+
+  /**
+   * Map from prefix names to their corresponding elements.
+   */
+  final HashMap<String, PrefixElementImpl> nameToPrefixMap =
+      new HashMap<String, PrefixElementImpl>();
+
+  /**
+   * Indicates whether an explicit import of `dart:core` has been found.
+   */
+  bool explicitlyImportsCore = false;
+
+  DirectiveElementBuilder(
+      this.context,
+      this.libraryElement,
+      this.sourceModificationTimeMap,
+      this.importLibraryMap,
+      this.importSourceKindMap,
+      this.exportLibraryMap,
+      this.exportSourceKindMap);
+
+  @override
+  Object visitCompilationUnit(CompilationUnit node) {
+    //
+    // Resolve directives.
+    //
+    for (Directive directive in node.directives) {
+      directive.accept(this);
+    }
+    //
+    // Ensure "dart:core" import.
+    //
+    Source librarySource = libraryElement.source;
+    Source coreLibrarySource = context.sourceFactory.forUri(DartSdk.DART_CORE);
+    if (!explicitlyImportsCore && coreLibrarySource != librarySource) {
+      ImportElementImpl importElement = new ImportElementImpl(-1);
+      importElement.importedLibrary = importLibraryMap[coreLibrarySource];
+      importElement.synthetic = true;
+      imports.add(importElement);
+    }
+    //
+    // Populate the library element.
+    //
+    libraryElement.imports = imports;
+    libraryElement.exports = exports;
+    return null;
+  }
+
+  @override
+  Object visitExportDirective(ExportDirective node) {
+    // Remove previous element. (It will remain null if the target is missing.)
+    node.element = null;
+    Source exportedSource = node.selectedSource;
+    int exportedTime = sourceModificationTimeMap[exportedSource] ?? -1;
+    // The exported source will be null if the URI in the export
+    // directive was invalid.
+    LibraryElement exportedLibrary = exportLibraryMap[exportedSource];
+    if (exportedLibrary != null) {
+      ExportElementImpl exportElement = new ExportElementImpl(node.offset);
+      exportElement.metadata = _getElementAnnotations(node.metadata);
+      StringLiteral uriLiteral = node.uri;
+      if (uriLiteral != null) {
+        exportElement.uriOffset = uriLiteral.offset;
+        exportElement.uriEnd = uriLiteral.end;
+      }
+      exportElement.uri = node.selectedUriContent;
+      exportElement.combinators = _buildCombinators(node);
+      exportElement.exportedLibrary = exportedLibrary;
+      setElementDocumentationComment(exportElement, node);
+      node.element = exportElement;
+      exports.add(exportElement);
+      if (exportedTime >= 0 &&
+          exportSourceKindMap[exportedSource] != SourceKind.LIBRARY) {
+        int offset = node.offset;
+        int length = node.length;
+        if (uriLiteral != null) {
+          offset = uriLiteral.offset;
+          length = uriLiteral.length;
+        }
+        errors.add(new AnalysisError(
+            libraryElement.source,
+            offset,
+            length,
+            CompileTimeErrorCode.EXPORT_OF_NON_LIBRARY,
+            [uriLiteral.toSource()]));
+      }
+    }
+    return null;
+  }
+
+  @override
+  Object visitImportDirective(ImportDirective node) {
+    // Remove previous element. (It will remain null if the target is missing.)
+    node.element = null;
+    Source importedSource = node.selectedSource;
+    int importedTime = sourceModificationTimeMap[importedSource] ?? -1;
+    // The imported source will be null if the URI in the import
+    // directive was invalid.
+    LibraryElement importedLibrary = importLibraryMap[importedSource];
+    if (importedLibrary != null) {
+      if (importedLibrary.isDartCore) {
+        explicitlyImportsCore = true;
+      }
+      ImportElementImpl importElement = new ImportElementImpl(node.offset);
+      importElement.metadata = _getElementAnnotations(node.metadata);
+      StringLiteral uriLiteral = node.uri;
+      if (uriLiteral != null) {
+        importElement.uriOffset = uriLiteral.offset;
+        importElement.uriEnd = uriLiteral.end;
+      }
+      importElement.uri = node.selectedUriContent;
+      importElement.deferred = node.deferredKeyword != null;
+      importElement.combinators = _buildCombinators(node);
+      importElement.importedLibrary = importedLibrary;
+      setElementDocumentationComment(importElement, node);
+      SimpleIdentifier prefixNode = node.prefix;
+      if (prefixNode != null) {
+        importElement.prefixOffset = prefixNode.offset;
+        String prefixName = prefixNode.name;
+        PrefixElementImpl prefix = nameToPrefixMap[prefixName];
+        if (prefix == null) {
+          prefix = new PrefixElementImpl.forNode(prefixNode);
+          nameToPrefixMap[prefixName] = prefix;
+        }
+        importElement.prefix = prefix;
+        prefixNode.staticElement = prefix;
+      }
+      node.element = importElement;
+      imports.add(importElement);
+      if (importedTime >= 0 &&
+          importSourceKindMap[importedSource] != SourceKind.LIBRARY) {
+        int offset = node.offset;
+        int length = node.length;
+        if (uriLiteral != null) {
+          offset = uriLiteral.offset;
+          length = uriLiteral.length;
+        }
+        ErrorCode errorCode = importElement.isDeferred
+            ? StaticWarningCode.IMPORT_OF_NON_LIBRARY
+            : CompileTimeErrorCode.IMPORT_OF_NON_LIBRARY;
+        errors.add(new AnalysisError(libraryElement.source, offset, length,
+            errorCode, [uriLiteral.toSource()]));
+      }
+    }
+    return null;
+  }
+
+  @override
+  Object visitLibraryDirective(LibraryDirective node) {
+    (node.element as LibraryElementImpl)?.metadata =
+        _getElementAnnotations(node.metadata);
+    return null;
+  }
+
+  @override
+  Object visitPartDirective(PartDirective node) {
+    (node.element as CompilationUnitElementImpl)?.metadata =
+        _getElementAnnotations(node.metadata);
+    return null;
+  }
+
+  /**
+   * Gather a list of the [ElementAnnotation]s referred to by the [Annotation]s
+   * in [metadata].
+   */
+  List<ElementAnnotation> _getElementAnnotations(
+      NodeList<Annotation> metadata) {
+    if (metadata.isEmpty) {
+      return ElementAnnotation.EMPTY_LIST;
+    }
+    return metadata.map((Annotation a) => a.elementAnnotation).toList();
+  }
+
+  /**
+   * Build the element model representing the combinators declared by
+   * the given [directive].
+   */
+  static List<NamespaceCombinator> _buildCombinators(
+      NamespaceDirective directive) {
+    _NamespaceCombinatorBuilder namespaceCombinatorBuilder =
+        new _NamespaceCombinatorBuilder();
+    for (Combinator combinator in directive.combinators) {
+      combinator.accept(namespaceCombinatorBuilder);
+    }
+    return namespaceCombinatorBuilder.combinators;
+  }
+}
+
+/**
+ * Instances of the class `ElementBuilder` traverse an AST structure and build the element
+ * model representing the AST structure.
+ */
+class ElementBuilder extends ApiElementBuilder {
+  /**
+   * Initialize a newly created element builder to build the elements for a
+   * compilation unit. The [initialHolder] is the element holder to which the
+   * children of the visited compilation unit node will be added.
+   */
+  ElementBuilder(ElementHolder initialHolder,
+      CompilationUnitElement compilationUnitElement)
+      : super(initialHolder, compilationUnitElement);
+
+  @override
+  Object visitBlockFunctionBody(BlockFunctionBody node) {
+    _buildLocal(node);
+    return null;
+  }
+
+  @override
+  Object visitExpressionFunctionBody(ExpressionFunctionBody node) {
+    _buildLocal(node);
+    return null;
+  }
+
+  @override
+  Object visitVariableDeclaration(VariableDeclaration node) {
+    super.visitVariableDeclaration(node);
+    VariableElementImpl element = node.element as VariableElementImpl;
+    _buildVariableInitializer(element, node.initializer);
+    return null;
+  }
+
+  void _buildLocal(AstNode node) {
+    node.accept(
+        new LocalElementBuilder(_currentHolder, compilationUnitElement));
+  }
+}
+
+/**
+ * Traverse a [FunctionBody] and build elements for AST structures.
+ */
+class LocalElementBuilder extends _BaseElementBuilder {
+  /**
+   * Initialize a newly created element builder to build the elements for a
+   * compilation unit. The [initialHolder] is the element holder to which the
+   * children of the visited compilation unit node will be added.
+   */
+  LocalElementBuilder(ElementHolder initialHolder,
+      CompilationUnitElementImpl compilationUnitElement)
+      : super(initialHolder, compilationUnitElement);
+
+  @override
+  Object visitCatchClause(CatchClause node) {
+    SimpleIdentifier exceptionParameter = node.exceptionParameter;
+    if (exceptionParameter != null) {
+      // exception
+      LocalVariableElementImpl exception =
+          new LocalVariableElementImpl.forNode(exceptionParameter);
+      if (node.exceptionType == null) {
+        exception.hasImplicitType = true;
+      }
+      exception.setVisibleRange(node.offset, node.length);
+      _currentHolder.addLocalVariable(exception);
+      exceptionParameter.staticElement = exception;
+      // stack trace
+      SimpleIdentifier stackTraceParameter = node.stackTraceParameter;
+      if (stackTraceParameter != null) {
+        LocalVariableElementImpl stackTrace =
+            new LocalVariableElementImpl.forNode(stackTraceParameter);
+        _setCodeRange(stackTrace, stackTraceParameter);
+        stackTrace.setVisibleRange(node.offset, node.length);
+        _currentHolder.addLocalVariable(stackTrace);
+        stackTraceParameter.staticElement = stackTrace;
+      }
+    }
+    return super.visitCatchClause(node);
+  }
+
+  @override
+  Object visitDeclaredIdentifier(DeclaredIdentifier node) {
+    SimpleIdentifier variableName = node.identifier;
+    LocalVariableElementImpl element =
+        new LocalVariableElementImpl.forNode(variableName);
+    _setCodeRange(element, node);
+    element.metadata = _createElementAnnotations(node.metadata);
+    ForEachStatement statement = node.parent as ForEachStatement;
+    element.setVisibleRange(statement.offset, statement.length);
+    element.const3 = node.isConst;
+    element.final2 = node.isFinal;
+    if (node.type == null) {
+      element.hasImplicitType = true;
+    }
+    _currentHolder.addLocalVariable(element);
+    variableName.staticElement = element;
+    return null;
+  }
+
+  @override
+  Object visitFunctionDeclaration(FunctionDeclaration node) {
+    FunctionExpression expression = node.functionExpression;
+    if (expression == null) {
+      return null;
+    }
+
+    ElementHolder holder = new ElementHolder();
+    _visitChildren(holder, node);
+
+    FunctionElementImpl element = new FunctionElementImpl.forNode(node.name);
+    _setCodeRange(element, node);
+    setElementDocumentationComment(element, node);
+    element.metadata = _createElementAnnotations(node.metadata);
+    if (node.externalKeyword != null) {
+      element.external = true;
+    }
+    element.functions = holder.functions;
+    element.labels = holder.labels;
+    element.localVariables = holder.localVariables;
+    element.parameters = holder.parameters;
+    element.typeParameters = holder.typeParameters;
+
+    FunctionBody body = expression.body;
+    if (body.isAsynchronous) {
+      element.asynchronous = body.isAsynchronous;
+    }
+    if (body.isGenerator) {
+      element.generator = true;
+    }
+
+    {
+      Block enclosingBlock = node.getAncestor((node) => node is Block);
+      if (enclosingBlock != null) {
+        element.setVisibleRange(enclosingBlock.offset, enclosingBlock.length);
+      }
+    }
+
+    if (node.returnType == null) {
+      element.hasImplicitReturnType = true;
+    }
+
+    _currentHolder.addFunction(element);
+    expression.element = element;
+    node.name.staticElement = element;
+    holder.validate();
+    return null;
+  }
+
+  @override
+  Object visitFunctionExpression(FunctionExpression node) {
+    if (node.parent is FunctionDeclaration) {
+      // visitFunctionDeclaration has already created the element for the
+      // declaration.  We just need to visit children.
+      return super.visitFunctionExpression(node);
+    }
+
+    ElementHolder holder = new ElementHolder();
+    _visitChildren(holder, node);
+    FunctionElementImpl element =
+        new FunctionElementImpl.forOffset(node.beginToken.offset);
+    _setCodeRange(element, node);
+    element.functions = holder.functions;
+    element.labels = holder.labels;
+    element.localVariables = holder.localVariables;
+    element.parameters = holder.parameters;
+    element.typeParameters = holder.typeParameters;
+
+    FunctionBody body = node.body;
+    if (body.isAsynchronous) {
+      element.asynchronous = true;
+    }
+    if (body.isGenerator) {
+      element.generator = true;
+    }
+
+    {
+      Block enclosingBlock = node.getAncestor((node) => node is Block);
+      if (enclosingBlock != null) {
+        element.setVisibleRange(enclosingBlock.offset, enclosingBlock.length);
+      }
+    }
+
+    element.type = new FunctionTypeImpl(element);
+    element.hasImplicitReturnType = true;
+    _currentHolder.addFunction(element);
+    node.element = element;
+    holder.validate();
+    return null;
+  }
+
+  @override
+  Object visitLabeledStatement(LabeledStatement node) {
+    bool onSwitchStatement = node.statement is SwitchStatement;
+    for (Label label in node.labels) {
+      SimpleIdentifier labelName = label.label;
+      LabelElementImpl element =
+          new LabelElementImpl.forNode(labelName, onSwitchStatement, false);
+      _currentHolder.addLabel(element);
+      labelName.staticElement = element;
+    }
+    return super.visitLabeledStatement(node);
+  }
+
+  @override
+  Object visitSwitchCase(SwitchCase node) {
+    for (Label label in node.labels) {
+      SimpleIdentifier labelName = label.label;
+      LabelElementImpl element =
+          new LabelElementImpl.forNode(labelName, false, true);
+      _currentHolder.addLabel(element);
+      labelName.staticElement = element;
+    }
+    return super.visitSwitchCase(node);
+  }
+
+  @override
+  Object visitSwitchDefault(SwitchDefault node) {
+    for (Label label in node.labels) {
+      SimpleIdentifier labelName = label.label;
+      LabelElementImpl element =
+          new LabelElementImpl.forNode(labelName, false, true);
+      _currentHolder.addLabel(element);
+      labelName.staticElement = element;
+    }
+    return super.visitSwitchDefault(node);
+  }
+
+  @override
+  Object visitVariableDeclaration(VariableDeclaration node) {
+    bool isConst = node.isConst;
+    bool isFinal = node.isFinal;
+    Expression initializerNode = node.initializer;
+    VariableDeclarationList varList = node.parent;
+    SimpleIdentifier variableName = node.name;
+    LocalVariableElementImpl element;
+    if (isConst && initializerNode != null) {
+      element = new ConstLocalVariableElementImpl.forNode(variableName);
+    } else {
+      element = new LocalVariableElementImpl.forNode(variableName);
+    }
+    _setCodeRange(element, node);
+    _setVariableVisibleRange(element, node);
+    element.hasImplicitType = varList.type == null;
+    _currentHolder.addLocalVariable(element);
+    variableName.staticElement = element;
+    element.const3 = isConst;
+    element.final2 = isFinal;
+    _buildVariableInitializer(element, initializerNode);
+    return null;
+  }
+
+  @override
+  Object visitVariableDeclarationList(VariableDeclarationList node) {
+    super.visitVariableDeclarationList(node);
+    List<ElementAnnotation> elementAnnotations =
+        _createElementAnnotations(node.metadata);
+    _setVariableDeclarationListAnnotations(node, elementAnnotations);
+    return null;
+  }
+
+  void _setVariableVisibleRange(
+      LocalVariableElementImpl element, VariableDeclaration node) {
+    AstNode scopeNode;
+    AstNode parent2 = node.parent.parent;
+    if (parent2 is ForStatement) {
+      scopeNode = parent2;
+    } else {
+      scopeNode = node.getAncestor((node) => node is Block);
+    }
+    element.setVisibleRange(scopeNode.offset, scopeNode.length);
+  }
+}
+
+/**
+ * Base class for API and local element builders.
+ */
+abstract class _BaseElementBuilder extends RecursiveAstVisitor<Object> {
+  /**
+   * The compilation unit element into which the elements being built will be
+   * stored.
+   */
+  final CompilationUnitElementImpl compilationUnitElement;
+
+  /**
+   * The element holder associated with the element that is currently being built.
+   */
+  ElementHolder _currentHolder;
+
+  _BaseElementBuilder(this._currentHolder, this.compilationUnitElement);
+
+  @override
+  Object visitDefaultFormalParameter(DefaultFormalParameter node) {
+    ElementHolder holder = new ElementHolder();
+    NormalFormalParameter normalParameter = node.parameter;
+    SimpleIdentifier parameterName = normalParameter.identifier;
+    ParameterElementImpl parameter;
+    if (normalParameter is FieldFormalParameter) {
+      DefaultFieldFormalParameterElementImpl fieldParameter =
+          new DefaultFieldFormalParameterElementImpl.forNode(parameterName);
+      _setFieldParameterField(fieldParameter);
+      parameter = fieldParameter;
+    } else {
+      parameter = new DefaultParameterElementImpl.forNode(parameterName);
+    }
+    _setCodeRange(parameter, node);
+    parameter.const3 = node.isConst;
+    parameter.final2 = node.isFinal;
+    parameter.parameterKind = node.kind;
+    // set initializer, default value range
+    Expression defaultValue = node.defaultValue;
+    if (defaultValue != null) {
+      _visit(holder, defaultValue);
+      FunctionElementImpl initializer =
+          new FunctionElementImpl.forOffset(defaultValue.beginToken.offset);
+      initializer.hasImplicitReturnType = true;
+      initializer.functions = holder.functions;
+      initializer.labels = holder.labels;
+      initializer.localVariables = holder.localVariables;
+      initializer.parameters = holder.parameters;
+      initializer.synthetic = true;
+      initializer.type = new FunctionTypeImpl(initializer);
+      parameter.initializer = initializer;
+      parameter.defaultValueCode = defaultValue.toSource();
+    }
+    // visible range
+    _setParameterVisibleRange(node, parameter);
+    if (normalParameter is SimpleFormalParameter &&
+        normalParameter.type == null) {
+      parameter.hasImplicitType = true;
+    }
+    _currentHolder.addParameter(parameter);
+    parameterName.staticElement = parameter;
+    normalParameter.accept(this);
+    holder.validate();
+    return null;
+  }
+
+  @override
+  Object visitFunctionTypedFormalParameter(FunctionTypedFormalParameter node) {
+    if (node.parent is! DefaultFormalParameter) {
+      SimpleIdentifier parameterName = node.identifier;
+      ParameterElementImpl parameter =
+          new ParameterElementImpl.forNode(parameterName);
+      _setCodeRange(parameter, node);
+      parameter.parameterKind = node.kind;
+      _setParameterVisibleRange(node, parameter);
+      _currentHolder.addParameter(parameter);
+      parameterName.staticElement = parameter;
+    }
+    //
+    // The children of this parameter include any parameters defined on the type
+    //of this parameter.
+    //
+    ElementHolder holder = new ElementHolder();
+    _visitChildren(holder, node);
+    ParameterElementImpl element = node.element;
+    element.metadata = _createElementAnnotations(node.metadata);
+    element.parameters = holder.parameters;
+    element.typeParameters = holder.typeParameters;
+    holder.validate();
+    return null;
   }
 
   @override
@@ -1094,30 +1456,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   @override
-  Object visitSwitchCase(SwitchCase node) {
-    for (Label label in node.labels) {
-      SimpleIdentifier labelName = label.label;
-      LabelElementImpl element =
-          new LabelElementImpl.forNode(labelName, false, true);
-      _currentHolder.addLabel(element);
-      labelName.staticElement = element;
-    }
-    return super.visitSwitchCase(node);
-  }
-
-  @override
-  Object visitSwitchDefault(SwitchDefault node) {
-    for (Label label in node.labels) {
-      SimpleIdentifier labelName = label.label;
-      LabelElementImpl element =
-          new LabelElementImpl.forNode(labelName, false, true);
-      _currentHolder.addLabel(element);
-      labelName.staticElement = element;
-    }
-    return super.visitSwitchDefault(node);
-  }
-
-  @override
   Object visitTypeParameter(TypeParameter node) {
     SimpleIdentifier parameterName = node.name;
     TypeParameterElementImpl typeParameter =
@@ -1132,68 +1470,12 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
     return super.visitTypeParameter(node);
   }
 
-  @override
-  Object visitVariableDeclaration(VariableDeclaration node) {
-    bool isConst = node.isConst;
-    bool isFinal = node.isFinal;
-    bool hasInitializer = node.initializer != null;
-    VariableDeclarationList varList = node.parent;
-    FieldDeclaration fieldNode =
-        varList.parent is FieldDeclaration ? varList.parent : null;
-    VariableElementImpl element;
-    if (fieldNode != null) {
-      SimpleIdentifier fieldName = node.name;
-      FieldElementImpl field;
-      if ((isConst || isFinal && !fieldNode.isStatic) && hasInitializer) {
-        field = new ConstFieldElementImpl.forNode(fieldName);
-      } else {
-        field = new FieldElementImpl.forNode(fieldName);
-      }
-      element = field;
-      field.static = fieldNode.isStatic;
-      _setCodeRange(element, node);
-      setElementDocumentationComment(element, fieldNode);
-      field.hasImplicitType = varList.type == null;
-      _currentHolder.addField(field);
-      fieldName.staticElement = field;
-    } else if (_inFunction) {
-      SimpleIdentifier variableName = node.name;
-      LocalVariableElementImpl variable;
-      if (isConst && hasInitializer) {
-        variable = new ConstLocalVariableElementImpl.forNode(variableName);
-      } else {
-        variable = new LocalVariableElementImpl.forNode(variableName);
-      }
-      element = variable;
-      _setCodeRange(element, node);
-      _setVariableVisibleRange(variable, node);
-      variable.hasImplicitType = varList.type == null;
-      _currentHolder.addLocalVariable(variable);
-      variableName.staticElement = element;
-    } else {
-      SimpleIdentifier variableName = node.name;
-      TopLevelVariableElementImpl variable;
-      if (isConst && hasInitializer) {
-        variable = new ConstTopLevelVariableElementImpl.forNode(variableName);
-      } else {
-        variable = new TopLevelVariableElementImpl.forNode(variableName);
-      }
-      element = variable;
-      _setCodeRange(element, node);
-      if (varList.parent is TopLevelVariableDeclaration) {
-        setElementDocumentationComment(element, varList.parent);
-      }
-      variable.hasImplicitType = varList.type == null;
-      _currentHolder.addTopLevelVariable(variable);
-      variableName.staticElement = element;
-    }
-    element.const3 = isConst;
-    element.final2 = isFinal;
-    if (hasInitializer) {
+  void _buildVariableInitializer(VariableElementImpl element, Expression node) {
+    if (node != null) {
       ElementHolder holder = new ElementHolder();
-      _visit(holder, node.initializer);
+      _visit(holder, node);
       FunctionElementImpl initializer =
-          new FunctionElementImpl.forOffset(node.initializer.beginToken.offset);
+          new FunctionElementImpl.forOffset(node.beginToken.offset);
       initializer.hasImplicitReturnType = true;
       initializer.functions = holder.functions;
       initializer.labels = holder.labels;
@@ -1203,68 +1485,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
       element.initializer = initializer;
       holder.validate();
     }
-    if (element is PropertyInducingElementImpl) {
-      PropertyAccessorElementImpl_ImplicitGetter getter =
-          new PropertyAccessorElementImpl_ImplicitGetter(element);
-      _currentHolder.addAccessor(getter);
-      if (!isConst && !isFinal) {
-        PropertyAccessorElementImpl_ImplicitSetter setter =
-            new PropertyAccessorElementImpl_ImplicitSetter(element);
-        _currentHolder.addAccessor(setter);
-      }
-    }
-    return null;
-  }
-
-  @override
-  Object visitVariableDeclarationList(VariableDeclarationList node) {
-    super.visitVariableDeclarationList(node);
-    AstNode parent = node.parent;
-    List<ElementAnnotation> elementAnnotations;
-    if (parent is FieldDeclaration) {
-      elementAnnotations = _createElementAnnotations(parent.metadata);
-    } else if (parent is TopLevelVariableDeclaration) {
-      elementAnnotations = _createElementAnnotations(parent.metadata);
-    } else {
-      // Local variable declaration
-      elementAnnotations = _createElementAnnotations(node.metadata);
-    }
-    for (VariableDeclaration variableDeclaration in node.variables) {
-      ElementImpl element = variableDeclaration.element as ElementImpl;
-      _setCodeRange(element, node.parent);
-      element.metadata = elementAnnotations;
-    }
-    return null;
-  }
-
-  /**
-   * Build the table mapping field names to field elements for the fields defined in the current
-   * class.
-   *
-   * @param fields the field elements defined in the current class
-   */
-  void _buildFieldMap(List<FieldElement> fields) {
-    _fieldMap = new HashMap<String, FieldElement>();
-    int count = fields.length;
-    for (int i = 0; i < count; i++) {
-      FieldElement field = fields[i];
-      _fieldMap[field.name] ??= field;
-    }
-  }
-
-  /**
-   * Creates the [ConstructorElement]s array with the single default constructor element.
-   *
-   * @param interfaceType the interface type for which to create a default constructor
-   * @return the [ConstructorElement]s array with the single default constructor element
-   */
-  List<ConstructorElement> _createDefaultConstructors(
-      ClassElementImpl definingClass) {
-    ConstructorElementImpl constructor =
-        new ConstructorElementImpl.forNode(null);
-    constructor.synthetic = true;
-    constructor.enclosingElement = definingClass;
-    return <ConstructorElement>[constructor];
   }
 
   /**
@@ -1285,28 +1505,6 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
   }
 
   /**
-   * Create the types associated with the given type parameters, setting the type of each type
-   * parameter, and return an array of types corresponding to the given parameters.
-   *
-   * @param typeParameters the type parameters for which types are to be created
-   * @return an array of types corresponding to the given parameters
-   */
-  List<DartType> _createTypeParameterTypes(
-      List<TypeParameterElement> typeParameters) {
-    int typeParameterCount = typeParameters.length;
-    List<DartType> typeArguments = new List<DartType>(typeParameterCount);
-    for (int i = 0; i < typeParameterCount; i++) {
-      TypeParameterElementImpl typeParameter =
-          typeParameters[i] as TypeParameterElementImpl;
-      TypeParameterTypeImpl typeParameterType =
-          new TypeParameterTypeImpl(typeParameter);
-      typeParameter.type = typeParameterType;
-      typeArguments[i] = typeParameterType;
-    }
-    return typeArguments;
-  }
-
-  /**
    * Return the body of the function that contains the given [parameter], or
    * `null` if no function body could be found.
    */
@@ -1326,6 +1524,8 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
     element.setCodeRange(node.offset, node.length);
   }
 
+  void _setFieldParameterField(FieldFormalParameterElementImpl parameter) {}
+
   /**
    * Sets the visible source range for formal parameter.
    */
@@ -1337,16 +1537,13 @@ class ElementBuilder extends RecursiveAstVisitor<Object> {
     }
   }
 
-  void _setVariableVisibleRange(
-      LocalVariableElementImpl element, VariableDeclaration node) {
-    AstNode scopeNode;
-    AstNode parent2 = node.parent.parent;
-    if (parent2 is ForStatement) {
-      scopeNode = parent2;
-    } else {
-      scopeNode = node.getAncestor((node) => node is Block);
+  void _setVariableDeclarationListAnnotations(VariableDeclarationList node,
+      List<ElementAnnotation> elementAnnotations) {
+    for (VariableDeclaration variableDeclaration in node.variables) {
+      ElementImpl element = variableDeclaration.element as ElementImpl;
+      _setCodeRange(element, node.parent);
+      element.metadata = elementAnnotations;
     }
-    element.setVisibleRange(scopeNode.offset, scopeNode.length);
   }
 
   /**