Book bridge example (not yet working)

example/bridge_example.dart

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+import 'package:dart_eval/dart_eval.dart';
+import 'package:dart_eval/dart_eval_bridge.dart';
+import 'package:dart_eval/dart_eval_extensions.dart';
+import 'package:dart_eval/stdlib/core.dart';
+
+/// An example class we want to bridge
+class Book {
+  Book(this.pages);
+
+  final List<String> pages;
+
+  String getPage(int index) => pages[index];
+}
+
+/// This is our bridge class
+class $Book$bridge extends Book with $Bridge<Book> {
+  static final $type = BridgeTypeSpec('package:hello/book.dart', 'Book').ref;
+
+  /// Create a class declaration for the dart_eval compiler
+  static final $declaration = BridgeClassDef(BridgeClassType($type),
+      constructors: {
+        // Define the default constructor with an empty string
+        '': BridgeFunctionDef(
+            returns: $type.annotate,
+            params: ['pages'.param(CoreTypes.list.ref.annotate)]).asConstructor
+      },
+      fields: {'pages': BridgeFieldDef(CoreTypes.list.ref.annotate)},
+      methods: {
+        'getPage': BridgeFunctionDef(
+          returns: CoreTypes.string.ref.annotate,
+          params: ['index'.param(CoreTypes.int.ref.annotate)],
+        ).asMethod,
+      },
+      bridge: true);
+
+  /// Recreate the original constructor
+  $Book$bridge(super.pages);
+
+  static $Value? $new(Runtime runtime, $Value? target, List<$Value?> args) {
+    return $Book$bridge((args[0]!.$reified as List).cast());
+  }
+
+  @override
+  $Value? $bridgeGet(String identifier) {
+    if (identifier == 'getPage') {
+      return $Function((_, target, args) {
+        return $String(getPage(args[0]!.$value));
+      });
+    }
+    throw UnimplementedError('Unknown property $identifier');
+  }
+
+  @override
+  $Value? $bridgeSet(String identifier, $Value value) =>
+      throw UnimplementedError('Unknown property $identifier');
+
+  @override
+  $Value? $getProperty(Runtime runtime, String identifier) {
+    switch (identifier) {
+      case 'pages':
+        // TODO: Now we just pass along the bridged/parent class' property, so values don't change...
+        return $List<$String>(identifier,
+            $List<$String>.wrap(pages.map((e) => $String(e)).toList()));
+      default:
+        return super.$getProperty(runtime, identifier);
+    }
+  }
+
+  /// Override the original class' properties and methods
+  @override
+  String getPage(int index) => $_invoke('getPage', [$int(index)]);
+
+  // @override
+  // List<String> get pages => $_get('pages');
+
+}
+
+void main() {
+  final compiler = Compiler();
+  compiler.defineBridgeClass($Book$bridge.$declaration);
+
+  final program = compiler.compile({
+    'hello': {
+      'main.dart': '''
+      import 'book.dart';
+      class MyBook extends Book {
+        MyBook(List<String> pages) : super(pages);
+        String getPage(int index) => 'Hello world!';
+      }
+
+      Book main() {
+        final book = MyBook(['Hi world!', 'Hello again!']);
+        book.pages.add('Next Chapter');
+        book.pages.add('Final Chapter');
+        return book;
+      }
+    '''
+    }
+  });
+
+  final runtime = Runtime.ofProgram(program);
+  runtime.registerBridgeFunc(
+      'package:hello/book.dart', 'Book.', $Book$bridge.$new,
+      isBridge: true);
+
+  // Now we can use the new book class outside dart_eval!
+  final book = runtime.executeLib('package:hello/main.dart', 'main') as Book;
+  print(book.getPage(1)); // -> 'Hello world!'
+  print(book is Book);
+  print(book is $Book$bridge);
+  // TODO: I'd expect the "Next Chapter" and "Final Chapter" here as well...
+  print(book.pages);
+}