Bind top level functions

lib/src/eval/bindgen/bindgen.dart

@@ -10,6 +10,7 @@ import 'package:dart_eval/src/eval/bindgen/bridge_declaration.dart';
 import 'package:dart_eval/src/eval/bindgen/configure.dart';
 import 'package:dart_eval/src/eval/bindgen/context.dart';
 import 'package:dart_eval/src/eval/bindgen/enum.dart';
+import 'package:dart_eval/src/eval/bindgen/function.dart';
 import 'package:dart_eval/src/eval/bindgen/methods.dart';
 import 'package:dart_eval/src/eval/bindgen/properties.dart';
 import 'package:dart_eval/src/eval/bindgen/statics.dart';
@@ -29,6 +30,7 @@ class Bindgen implements BridgeDeclarationRegistry {
   final _exportedLibMappings = <String, String>{};
   final List<({String file, String uri, String name})> registerClasses = [];
   final List<({String file, String uri, String name})> registerEnums = [];
+  final List<({String file, String uri, String name})> registerFunctions = [];
 
   AnalysisContextCollection? _contextCollection;
 
@@ -159,11 +161,16 @@ class Bindgen implements BridgeDeclarationRegistry {
       try {
         resolved = units
             .where((declaration) => declaration.declaredFragment != null)
-            .map((declaration) => declaration is ClassDeclaration
-                ? _$instance(ctx, declaration.declaredFragment!.element)
-                : (declaration is EnumDeclaration
-                    ? _$enum(ctx, declaration.declaredFragment!.element)
-                    : null))
+            .map((declaration) {
+              if (declaration is ClassDeclaration) {
+                return _$instance(ctx, declaration.declaredFragment!.element);
+              } else if (declaration is EnumDeclaration) {
+                return _$enum(ctx, declaration.declaredFragment!.element);
+              } else if (declaration is FunctionDeclaration) {
+                return _$function(ctx, declaration.declaredFragment!.element);
+              }
+              return null;
+            })
             .toList()
             .nonNulls;
       } on Error {
@@ -188,7 +195,7 @@ class Bindgen implements BridgeDeclarationRegistry {
   }
 
   ({bool process, bool isBridge}) _shouldProcess(
-      BindgenContext ctx, TypeDefiningElement2 element) {
+      BindgenContext ctx, Annotatable element) {
     final metadata = element.metadata2;
     final bindAnno = metadata.annotations
         .firstWhereOrNull((element) => element.element2?.displayName == 'Bind');
@@ -201,10 +208,10 @@ class Bindgen implements BridgeDeclarationRegistry {
         bindAnnoValue?.getField('implicitSupers')?.toBoolValue() ?? false;
     ctx.implicitSupers = implicitSupers;
     final override = bindAnnoValue?.getField('overrideLibrary');
-    if (override != null && !override.isNull) {
+    if (override != null && !override.isNull && element is Element2) {
       final overrideUri = override.toStringValue();
       if (overrideUri != null) {
-        ctx.libOverrides[element.name3!] = overrideUri;
+        ctx.libOverrides[(element as Element2).name3!] = overrideUri;
       }
     }
 
@@ -316,6 +323,31 @@ class \$${element.name3} implements \$Instance {
 ''';
   }
 
+  String? _$function(BindgenContext ctx, ExecutableElement2 element) {
+    if (element is! TopLevelFunctionElement) return null;
+    final (:process, :isBridge) = _shouldProcess(ctx, element);
+    if (!process) {
+      return null;
+    }
+
+    registerFunctions.add((
+      file: ctx.filename,
+      uri: ctx.libOverrides[element.name3!] ?? ctx.uri,
+      name: element.name3!,
+    ));
+
+    return '''
+/// dart_eval function wrapper binding for [${element.name3}]
+class \$${element.name3}Fn implements EvalCallable {
+  const \$${element.name3}Fn();
+
+  ${bindConfigureFunctionForRuntime(ctx, element)}
+  ${bindFunctionDeclaration(ctx, element)}
+  ${$function(ctx, element)}
+}
+''';
+  }
+
   String $superclassWrapper(BindgenContext ctx, InterfaceElement2 element) {
     final supertype = element.supertype;
     final objectWrapper = '\$Object(\$value)';

lib/src/eval/bindgen/bridge_declaration.dart

@@ -19,6 +19,18 @@ String bindBridgeType(BindgenContext ctx, InterfaceElement2 element) {
 ''';
 }
 
+String bindFunctionDeclaration(
+    BindgenContext ctx, TopLevelFunctionElement element) {
+  final uri = ctx.libOverrides[element.name3] ?? ctx.uri;
+  return '''
+  static const \$declaration = BridgeFunctionDeclaration(
+    '$uri',
+    '${element.name3!.replaceAll(r'$', r'\$')}',
+    ${bridgeFunctionDef(ctx, function: element)}
+  );
+''';
+}
+
 String? bindBridgeDeclaration(BindgenContext ctx, InterfaceElement2 element,
     {bool isBridge = false}) {
   if (element is ClassElement2 && element.constructors2.isEmpty) {
@@ -188,14 +200,21 @@ String bridgeConstructorDef(BindgenContext ctx,
       ''';
 }
 
-String bridgeMethodDef(BindgenContext ctx, {required MethodElement2 method}) {
+String bridgeFunctionDef(BindgenContext ctx,
+    {required ExecutableElement2 function}) {
   return '''
-      '${method.name3}': BridgeMethodDef(
         BridgeFunctionDef(
-          returns: ${bridgeTypeAnnotationFrom(ctx, method.returnType)},
-          namedParams: [${namedParameters(ctx, element: method)}],
-          params: [${positionalParameters(ctx, element: method)}],
+          returns: ${bridgeTypeAnnotationFrom(ctx, function.returnType)},
+          namedParams: [${namedParameters(ctx, element: function)}],
+          params: [${positionalParameters(ctx, element: function)}],
         ),
+''';
+}
+
+String bridgeMethodDef(BindgenContext ctx, {required MethodElement2 method}) {
+  return '''
+      '${method.name3}': BridgeMethodDef(
+        ${bridgeFunctionDef(ctx, function: method)}
         ${method.isStatic ? 'isStatic: true,' : ''}
       ),
 ''';
@@ -205,11 +224,7 @@ String bridgeGetterDef(BindgenContext ctx,
     {required PropertyAccessorElement2 getter}) {
   return '''
       '${getter.name3}': BridgeMethodDef(
-        BridgeFunctionDef(
-          returns: ${bridgeTypeAnnotationFrom(ctx, getter.returnType)},
-          namedParams: [${namedParameters(ctx, element: getter)}],
-          params: [${positionalParameters(ctx, element: getter)}],
-        ),
+        ${bridgeFunctionDef(ctx, function: getter)}
         ${getter.isStatic ? 'isStatic: true,' : ''}
       ),
 ''';
@@ -219,11 +234,7 @@ String bridgeSetterDef(BindgenContext ctx,
     {required PropertyAccessorElement2 setter}) {
   return '''
       '${setter.name3}': BridgeMethodDef(
-        BridgeFunctionDef(
-          returns: ${bridgeTypeAnnotationFrom(ctx, setter.returnType)},
-          namedParams: [${namedParameters(ctx, element: setter)}],
-          params: [${positionalParameters(ctx, element: setter)}],
-        ),
+        ${bridgeFunctionDef(ctx, function: setter)}
         ${setter.isStatic ? 'isStatic: true,' : ''}
       ),
 ''';

lib/src/eval/bindgen/configure.dart

@@ -22,6 +22,16 @@ static void configureForRuntime(Runtime runtime) {
 }
 ''';
 
+String bindConfigureFunctionForRuntime(
+    BindgenContext ctx, TopLevelFunctionElement element) {
+  final uri = ctx.libOverrides[element.name3] ?? ctx.uri;
+  return '''
+static void configureForRuntime(Runtime runtime) {
+  return runtime.registerBridgeFunc('$uri', '${element.name3!.replaceAll(r'$', r'\$')}', const \$${element.name3}Fn().call);
+}
+''';
+}
+
 String enumValuesForRuntime(BindgenContext ctx, EnumElement2 element) {
   final uri = ctx.libOverrides[element.name3] ?? ctx.uri;
   return '''

lib/src/eval/bindgen/function.dart

@@ -0,0 +1,16 @@
+import 'package:analyzer/dart/element/element2.dart';
+import 'package:analyzer/dart/element/type.dart';
+import 'package:dart_eval/src/eval/bindgen/context.dart';
+import 'package:dart_eval/src/eval/bindgen/parameters.dart';
+import 'package:dart_eval/src/eval/bindgen/type.dart';
+
+String $function(BindgenContext ctx, ExecutableElement2 element) {
+  final returnsValue =
+      element.returnType is! VoidType && !element.returnType.isDartCoreNull;
+  return '''
+        @override
+        \$Value? call(Runtime runtime, \$Value? target, List<\$Value?> args) {
+          ${returnsValue ? 'final result = ' : ''}${element.displayName}(${argumentAccessors(ctx, element.formalParameters).join(', ')});
+          return ${wrapVar(ctx, element.returnType, 'result')};
+        }''';
+}

lib/src/eval/cli/bind.dart

@@ -144,12 +144,14 @@ class ${packageName.toPascalCase()}Plugin implements EvalPlugin {
   void configureForCompile(BridgeDeclarationRegistry registry) {
     ${bindgen.registerClasses.map((e) => 'registry.defineBridgeClass(\$${e.name}.\$declaration);').join('\n')}
     ${bindgen.registerEnums.map((e) => 'registry.defineBridgeEnum(\$${e.name}.\$declaration);').join('\n')}
+    ${bindgen.registerFunctions.map((e) => 'registry.defineBridgeTopLevelFunction(\$${e.name}Fn.\$declaration);').join('\n')}
   }
 
   @override
   void configureForRuntime(Runtime runtime) {
     ${bindgen.registerClasses.map((e) => '\$${e.name}.configureForRuntime(runtime);').join('\n')}
     ${bindgen.registerEnums.map((e) => '\$${e.name}.configureForRuntime(runtime);').join('\n')}
+    ${bindgen.registerFunctions.map((e) => '\$${e.name}Fn.configureForRuntime(runtime);').join('\n')}
   }
 }
 ''';

lib/src/eval/compiler/reference.dart

@@ -638,7 +638,8 @@ Variable _declarationToVariable(
     final type = ctx.topLevelVariableInferredTypes[decOrBridge.sourceLib]![
         decl.name.lexeme];
     if (type == null) {
-      throw CompileError('Cannot resolve top level variable ${decl.name.lexeme}', source);
+      throw CompileError(
+          'Cannot resolve top level variable ${decl.name.lexeme}', source);
     }
     final gIndex =
         ctx.topLevelGlobalIndices[decOrBridge.sourceLib]![decl.name.lexeme]!;