| // Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| /// Implements support for Dart VM native method bodies of this form: |
| /// |
| /// native STRING |
| /// |
| /// This support is kept separate from parser.dart as this isn't specified in |
| /// the Dart Language Specification, also we hope to remove this syntax long |
| /// term and replace it with annotations as in `dart2js`. |
| library fasta.parser.dart_vm_native; |
| |
| import '../scanner/token.dart' show Token; |
| |
| import '../scanner/token_constants.dart' show STRING_TOKEN; |
| |
| import '../util/link.dart' show Link; |
| |
| import 'parser.dart' show optional; |
| |
| /// When parsing a Dart VM library file, we may encounter a native clause |
| /// instead of a function body. This method skips such a clause. |
| /// |
| /// This method is designed to be called when encountering |
| /// [ErrorKind.ExpectedBlockToSkip] in [Listener.handleUnrecoverableError]. |
| Token skipNativeClause(Token token) { |
| if (!optional("native", token)) return null; |
| token = token.next; |
| if (token.kind != STRING_TOKEN) return null; |
| if (!optional(";", token.next)) return null; |
| return token; |
| } |
| |
| /// When parsing a Dart VM library file, we may encounter native getters like |
| /// |
| /// int get length native "List_getLength"; |
| /// |
| /// This will result in [identifiers] being |
| /// |
| /// [";", '"List_getLength"', "native", "length", "get"] |
| /// |
| /// We need to remove '"List_getLength"' and "native" from that list. |
| /// |
| /// This method designed to be called from [Listener.handleMemberName]. |
| Link<Token> removeNativeClause(Link<Token> identifiers) { |
| Link<Token> result = identifiers.tail; |
| if (result.head.kind != STRING_TOKEN) return identifiers; |
| result = result.tail; |
| if (result.isEmpty) return identifiers; |
| if (optional('native', result.head)) { |
| return result.tail.prepend(identifiers.head); |
| } |
| return identifiers; |
| } |