| // Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| library computer.hover; |
| |
| import 'package:analysis_server/plugin/protocol/protocol.dart' |
| show HoverInformation; |
| import 'package:analysis_server/src/utilities/documentation.dart'; |
| import 'package:analyzer/dart/element/element.dart'; |
| import 'package:analyzer/src/generated/ast.dart'; |
| import 'package:analyzer/src/generated/element.dart'; |
| |
| /** |
| * A computer for the hover at the specified offset of a Dart [CompilationUnit]. |
| */ |
| class DartUnitHoverComputer { |
| final CompilationUnit _unit; |
| final int _offset; |
| |
| DartUnitHoverComputer(this._unit, this._offset); |
| |
| /** |
| * Returns the computed hover, maybe `null`. |
| */ |
| HoverInformation compute() { |
| AstNode node = new NodeLocator(_offset).searchWithin(_unit); |
| if (node == null) { |
| return null; |
| } |
| if (node.parent is TypeName && |
| node.parent.parent is ConstructorName && |
| node.parent.parent.parent is InstanceCreationExpression) { |
| node = node.parent.parent.parent; |
| } |
| if (node.parent is ConstructorName && |
| node.parent.parent is InstanceCreationExpression) { |
| node = node.parent.parent; |
| } |
| if (node is Expression) { |
| Expression expression = node; |
| HoverInformation hover = |
| new HoverInformation(expression.offset, expression.length); |
| // element |
| Element element = ElementLocator.locate(expression); |
| if (element != null) { |
| // variable, if synthetic accessor |
| if (element is PropertyAccessorElement) { |
| PropertyAccessorElement accessor = element; |
| if (accessor.isSynthetic) { |
| element = accessor.variable; |
| } |
| } |
| // description |
| hover.elementDescription = element.toString(); |
| hover.elementKind = element.kind.displayName; |
| // not local element |
| if (element.enclosingElement is! ExecutableElement) { |
| // containing class |
| ClassElement containingClass = |
| element.getAncestor((e) => e is ClassElement); |
| if (containingClass != null) { |
| hover.containingClassDescription = containingClass.displayName; |
| } |
| // containing library |
| LibraryElement library = element.library; |
| if (library != null) { |
| hover.containingLibraryName = library.name; |
| hover.containingLibraryPath = library.source.fullName; |
| } |
| } |
| |
| // documentation |
| hover.dartdoc = _computeDocumentation(element); |
| } |
| // parameter |
| hover.parameter = _safeToString(expression.bestParameterElement); |
| // types |
| if (element == null || element is VariableElement) { |
| hover.staticType = _safeToString(expression.staticType); |
| } |
| hover.propagatedType = _safeToString(expression.propagatedType); |
| // done |
| return hover; |
| } |
| // not an expression |
| return null; |
| } |
| |
| String _computeDocumentation(Element element) { |
| if (element is ParameterElement) { |
| element = element.enclosingElement; |
| } |
| return removeDartDocDelimiters(element.documentationComment); |
| } |
| |
| static _safeToString(obj) => obj != null ? obj.toString() : null; |
| } |