From 965ebf16cbf8e7ac572c7feb4fc7e8bb6aa08d4e Mon Sep 17 00:00:00 2001
From: Ethan <ethanblake@gmail.com>
Date: Mon, 8 Jan 2024 14:02:45 -0700
Subject: [PATCH] Better error message for invoking nonexistent bridged default
 constructor

---
 example/bridge_example.dart                   | 92 -------------------
 .../expression/method_invocation.dart         |  8 +-
 2 files changed, 7 insertions(+), 93 deletions(-)
 delete mode 100644 example/bridge_example.dart

diff --git a/example/bridge_example.dart b/example/bridge_example.dart
deleted file mode 100644
index f7a52d8..0000000
--- a/example/bridge_example.dart
+++ /dev/null
@@ -1,92 +0,0 @@
-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.string.ref.annotate)
-          'pages'.param(CoreTypes.list.ref.annotate)
-        ]).asConstructor
-      },
-      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 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(['Hello world!', 'Hello again!']);
-        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!'
-}
diff --git a/lib/src/eval/compiler/expression/method_invocation.dart b/lib/src/eval/compiler/expression/method_invocation.dart
index 353b53a..8f6358d 100644
--- a/lib/src/eval/compiler/expression/method_invocation.dart
+++ b/lib/src/eval/compiler/expression/method_invocation.dart
@@ -117,8 +117,14 @@ Variable compileMethodInvocation(CompilerContext ctx, MethodInvocation e,
 
   if (_dec.isBridge) {
     final bridge = _dec.bridge;
+
+    /// If we're invoking a class identifier directly (like ClassName()), call
+    /// its default constructor
     final fnDescriptor = bridge is BridgeClassDef
-        ? bridge.constructors['']!.functionDescriptor
+        ? (bridge.constructors['']?.functionDescriptor ??
+            (throw CompileError(
+                'Class "${e.methodName.name}" does not have a default constructor',
+                e)))
         : (bridge as BridgeFunctionDeclaration).function;
 
     final argsPair = compileArgumentListWithBridge(