| // Copyright (c) 2019, 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. |
| |
| import 'package:analyzer/dart/ast/ast.dart'; |
| import 'package:analyzer/dart/ast/visitor.dart'; |
| import 'package:analyzer/file_system/file_system.dart'; |
| import 'package:yaml/yaml.dart'; |
| |
| import '../analyzer.dart'; |
| import '../ast.dart'; |
| |
| const _desc = |
| r'Avoid using web-only libraries outside Flutter web plugin packages.'; |
| |
| const _details = r'''Avoid using web libraries, `dart:html`, `dart:js` and |
| `dart:js_util` in Flutter packages that are not web plugins. These libraries are |
| not supported outside a web context; functionality that depends on them will |
| fail at runtime in Flutter mobile, and their use is generally discouraged in |
| Flutter web. |
| |
| Web library access *is* allowed in: |
| |
| * plugin packages that declare `web` as a supported context |
| |
| otherwise, imports of `dart:html`, `dart:js` and `dart:js_util` are disallowed. |
| '''; |
| |
| /// todo (pq): consider making a utility and sharing w/ `prefer_relative_imports` |
| YamlMap _parseYaml(String content) { |
| try { |
| final doc = loadYamlNode(content); |
| if (doc is YamlMap) { |
| return doc; |
| } |
| // ignore: avoid_catches_without_on_clauses |
| } catch (_) { |
| // Fall-through. |
| } |
| return YamlMap(); |
| } |
| |
| class AvoidWebLibrariesInFlutter extends LintRule implements NodeLintRule { |
| AvoidWebLibrariesInFlutter() |
| : super( |
| name: 'avoid_web_libraries_in_flutter', |
| description: _desc, |
| details: _details, |
| maturity: Maturity.experimental, |
| group: Group.errors); |
| |
| @override |
| void registerNodeProcessors( |
| NodeLintRegistry registry, LinterContext context) { |
| final visitor = _Visitor(this); |
| registry.addCompilationUnit(this, visitor); |
| registry.addImportDirective(this, visitor); |
| } |
| } |
| |
| class _Visitor extends SimpleAstVisitor<void> { |
| File pubspecFile; |
| |
| final rule; |
| bool _shouldValidateUri; |
| |
| _Visitor(this.rule); |
| |
| bool get shouldValidateUri => _shouldValidateUri ??= checkForValidation(); |
| |
| bool checkForValidation() { |
| if (pubspecFile == null) { |
| return false; |
| } |
| |
| var parsedPubspec; |
| try { |
| final content = pubspecFile.readAsStringSync(); |
| parsedPubspec = _parseYaml(content); |
| // ignore: avoid_catches_without_on_clauses |
| } catch (_) { |
| return false; |
| } |
| |
| // Check for Flutter. |
| if ((parsedPubspec['dependencies'] ?? const {})['flutter'] == null) { |
| return false; |
| } |
| |
| // Check for a web plugin context declaration. |
| return (((parsedPubspec['flutter'] ?? const {})['plugin'] ?? |
| const {})['platforms'] ?? |
| const {})['web'] == |
| null; |
| } |
| |
| bool isWebUri(String uri) { |
| final uriLength = uri.length; |
| return (uriLength == 9 && uri == 'dart:html') || |
| (uriLength == 7 && uri == 'dart:js') || |
| (uriLength == 12 && uri == 'dart:js_util'); |
| } |
| |
| @override |
| void visitCompilationUnit(CompilationUnit node) { |
| pubspecFile = locatePubspecFile(node); |
| } |
| |
| @override |
| void visitImportDirective(ImportDirective node) { |
| if (isWebUri(node.uri.stringValue) && shouldValidateUri) { |
| rule.reportLint(node); |
| } |
| } |
| } |