lib/src/flutter_web.dart

// 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 'dart:io';

import 'package:analyzer/dart/ast/ast.dart';
import 'package:path/path.dart' as path;

/// Support for handling Flutter web snippets.
class FlutterWebManager {
  static Directory flutterTemplateProject(bool nullSafety) =>
      Directory(path.join(
        Directory.current.path,
        'project_templates',
        nullSafety ? 'null-safe' : 'null-unsafe',
        'flutter_project',
      ));

  static Directory dartTemplateProject(bool nullSafety) => Directory(path.join(
        Directory.current.path,
        'project_templates',
        nullSafety ? 'null-safe' : 'null-unsafe',
        'dart_project',
      ));

  FlutterWebManager();

  String summaryFilePath(bool nullSafety) {
    return path.join(
      'artifacts',
      nullSafety ? 'null-safe' : 'null-unsafe',
      'flutter_web.dill',
    );
  }

  static const Set<String> _flutterImportPrefixes = {
    'package:cloud_firestore/',
    'package:firebase/',
    'package:firebase_auth/',
    'package:firebase_core/',
    'package:flutter/',
    'dart:ui',
  };

  /// A set of all allowed `dart:` imports. Currently includes non-VM libraries
  /// listed as the [doc](https://api.dart.dev/stable/index.html) categories.
  static const Set<String> _allowedDartImports = {
    'dart:async',
    'dart:collection',
    'dart:convert',
    'dart:core',
    'dart:developer',
    'dart:math',
    'dart:typed_data',
    'dart:html',
    'dart:indexed_db',
    'dart:js',
    'dart:js_util',
    'dart:svg',
    'dart:web_audio',
    'dart:web_gl',
    'dart:web_sql',
    'dart:ui',
  };

  bool usesFlutterWeb(Iterable<ImportDirective> imports) {
    return imports.any((import) {
      return _flutterImportPrefixes
          .any((String prefix) => import.uri.stringValue.startsWith(prefix));
    });
  }

  List<ImportDirective> getUnsupportedImports(List<ImportDirective> imports) {
    return imports.where((import) {
      final uri = import.uri.stringValue;
      // All non-VM 'dart:' imports are ok.
      if (uri.startsWith('dart:')) {
        return !_allowedDartImports.contains(uri);
      }

      // Currently we only allow flutter web imports.
      if (uri.startsWith('package:')) {
        return !_flutterImportPrefixes
            .any((String prefix) => uri.startsWith(prefix));
      }

      // Don't allow file imports.
      return true;
    }).toList();
  }
}