[dart2js] Add interceptors for JavaScript Symbol and BigInt

The interceptors provide a Dart `toString` method that uses the JavaScript `toString` method.

Issue: #53106

Change-Id: I1cf1df9e24fb4fd2d79679f1f014f39f083be7e9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/319563
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Commit-Queue: Stephen Adams <sra@google.com>

pkg/compiler/lib/src/common/elements.dart

@@ -568,9 +568,15 @@ abstract class CommonElements {
   late final ClassEntity jsUnknownJavaScriptObjectClass =
       _findInterceptorsClass('UnknownJavaScriptObject');
 
+  late final ClassEntity jsJavaScriptBigIntClass =
+      _findInterceptorsClass('JavaScriptBigInt');
+
   late final ClassEntity jsJavaScriptFunctionClass =
       _findInterceptorsClass('JavaScriptFunction');
 
+  late final ClassEntity jsJavaScriptSymbolClass =
+      _findInterceptorsClass('JavaScriptSymbol');
+
   InterfaceType get jsJavaScriptFunctionType =>
       _getRawType(jsJavaScriptFunctionClass);
 

pkg/compiler/lib/src/js_backend/backend_impact.dart

@@ -395,7 +395,9 @@ class BackendImpacts {
       _commonElements.jsJavaScriptObjectClass,
       _commonElements.jsLegacyJavaScriptObjectClass,
       _commonElements.jsPlainJavaScriptObjectClass,
-      _commonElements.jsJavaScriptFunctionClass
+      _commonElements.jsJavaScriptBigIntClass,
+      _commonElements.jsJavaScriptFunctionClass,
+      _commonElements.jsJavaScriptSymbolClass
     ],
     features: EnumSet<BackendFeature>.fromValues([
       BackendFeature.needToInitializeDispatchProperty,
@@ -460,7 +462,9 @@ class BackendImpacts {
       _commonElements.jsJavaScriptObjectClass,
       _commonElements.jsLegacyJavaScriptObjectClass,
       _commonElements.jsPlainJavaScriptObjectClass,
-      _commonElements.jsJavaScriptFunctionClass
+      _commonElements.jsJavaScriptBigIntClass,
+      _commonElements.jsJavaScriptFunctionClass,
+      _commonElements.jsJavaScriptSymbolClass
     ],
   );
 

pkg/compiler/lib/src/js_backend/codegen_listener.dart

@@ -308,8 +308,12 @@ class CodegenEnqueuerListener extends EnqueuerListener {
       registerInstantiation(_commonElements.jsPlainJavaScriptObjectClass);
     } else if (cls == _commonElements.jsUnknownJavaScriptObjectClass) {
       registerInstantiation(_commonElements.jsUnknownJavaScriptObjectClass);
+    } else if (cls == _commonElements.jsJavaScriptBigIntClass) {
+      registerInstantiation(_commonElements.jsJavaScriptBigIntClass);
     } else if (cls == _commonElements.jsJavaScriptFunctionClass) {
       registerInstantiation(_commonElements.jsJavaScriptFunctionClass);
+    } else if (cls == _commonElements.jsJavaScriptSymbolClass) {
+      registerInstantiation(_commonElements.jsJavaScriptSymbolClass);
     } else if (cls == _commonElements.jsIndexingBehaviorInterface) {
       _impacts.jsIndexingBehavior
           .registerImpact(impactBuilder, _elementEnvironment);

pkg/compiler/lib/src/js_backend/resolution_listener.dart

@@ -400,9 +400,13 @@ class ResolutionEnqueuerListener extends EnqueuerListener {
     } else if (cls == _commonElements.jsUnknownJavaScriptObjectClass) {
       _addInterceptors(
           _commonElements.jsUnknownJavaScriptObjectClass, impactBuilder);
+    } else if (cls == _commonElements.jsJavaScriptBigIntClass) {
+      _addInterceptors(_commonElements.jsJavaScriptBigIntClass, impactBuilder);
     } else if (cls == _commonElements.jsJavaScriptFunctionClass) {
       _addInterceptors(
           _commonElements.jsJavaScriptFunctionClass, impactBuilder);
+    } else if (cls == _commonElements.jsJavaScriptSymbolClass) {
+      _addInterceptors(_commonElements.jsJavaScriptSymbolClass, impactBuilder);
     } else if (_nativeData.isNativeOrExtendsNative(cls)) {
       _interceptorData.addInterceptorsForNativeClassMembers(cls);
     } else if (cls == _commonElements.jsIndexingBehaviorInterface) {

pkg/compiler/lib/src/js_emitter/interceptor_stub_generator.dart

@@ -74,8 +74,12 @@ class InterceptorStubGenerator {
         condition = js('(typeof receiver) == "string"');
       } else if (cls == _commonElements.jsNullClass) {
         condition = js('receiver == null');
+      } else if (cls == _commonElements.jsJavaScriptBigIntClass) {
+        condition = js('(typeof receiver) == "bigint"');
       } else if (cls == _commonElements.jsJavaScriptFunctionClass) {
         condition = js('(typeof receiver) == "function"');
+      } else if (cls == _commonElements.jsJavaScriptSymbolClass) {
+        condition = js('(typeof receiver) == "symbol"');
       } else {
         throw 'internal error';
       }
@@ -92,7 +96,9 @@ class InterceptorStubGenerator {
     bool hasNative = false;
     bool anyNativeClasses = _nativeCodegenEnqueuer.hasInstantiatedNativeClasses;
     bool hasJavaScriptFunction = false;
+    bool hasJavaScriptBigInt = false;
     bool hasJavaScriptObject = false;
+    bool hasJavaScriptSymbol = false;
 
     for (ClassEntity cls in classes) {
       if (cls == _commonElements.jsArrayClass ||
@@ -112,8 +118,12 @@ class InterceptorStubGenerator {
         hasNumber = true;
       else if (cls == _commonElements.jsStringClass)
         hasString = true;
+      else if (cls == _commonElements.jsJavaScriptBigIntClass)
+        hasJavaScriptBigInt = true;
       else if (cls == _commonElements.jsJavaScriptFunctionClass)
         hasJavaScriptFunction = true;
+      else if (cls == _commonElements.jsJavaScriptSymbolClass)
+        hasJavaScriptSymbol = true;
       else if (cls == _commonElements.jsJavaScriptObjectClass)
         hasJavaScriptObject = true;
       else {
@@ -190,10 +200,20 @@ class InterceptorStubGenerator {
 
     // If a program `hasNative` then we will insert a check for
     // `JavaScriptFunction` in the `hasNative` block of the interceptor logic.
-    // Otherwise, we have to insert a specific check for `JavScriptFunction.
-    if (hasJavaScriptFunction && !hasNative) {
-      statements.add(
-          buildInterceptorCheck(_commonElements.jsJavaScriptFunctionClass));
+    // Otherwise, we have to insert a specific check for `JavaScriptFunction.
+    if (!hasNative) {
+      if (hasJavaScriptFunction) {
+        statements.add(
+            buildInterceptorCheck(_commonElements.jsJavaScriptFunctionClass));
+      }
+      if (hasJavaScriptSymbol) {
+        statements.add(
+            buildInterceptorCheck(_commonElements.jsJavaScriptSymbolClass));
+      }
+      if (hasJavaScriptBigInt) {
+        statements.add(
+            buildInterceptorCheck(_commonElements.jsJavaScriptBigIntClass));
+      }
     }
 
     if (hasJavaScriptObject && !hasNative) {
@@ -215,12 +235,16 @@ class InterceptorStubGenerator {
       statements.add(js.statement(r'''{
           if (typeof receiver != "object") {
               if (typeof receiver == "function" ) return #;
+              if (typeof receiver == "symbol" ) return #;
+              if (typeof receiver == "bigint" ) return #;
               return receiver;
           }
           if (receiver instanceof #) return receiver;
           return #(receiver);
       }''', [
         interceptorFor(_commonElements.jsJavaScriptFunctionClass),
+        interceptorFor(_commonElements.jsJavaScriptSymbolClass),
+        interceptorFor(_commonElements.jsJavaScriptBigIntClass),
         _emitter.constructorAccess(_commonElements.objectClass),
         _emitter
             .staticFunctionAccess(_commonElements.getNativeInterceptorMethod)

pkg/compiler/lib/src/native/enqueue.dart

@@ -92,7 +92,8 @@ abstract class NativeEnqueuer {
             type == _commonElements.stringType ||
             type == _commonElements.nullType ||
             type == _commonElements.boolType ||
-            type == _commonElements.jsJavaScriptFunctionType ||
+            type.element == _commonElements.jsJavaScriptBigIntClass ||
+            type.element == _commonElements.jsJavaScriptSymbolClass ||
             type == _commonElements.jsJavaScriptObjectType ||
             _dartTypes.isSubtype(type,
                 _elementEnvironment.getRawType(_commonElements.jsArrayClass))) {

sdk/lib/_internal/js_runtime/lib/interceptors.dart

@@ -464,3 +464,41 @@ final class JavaScriptFunction extends LegacyJavaScriptObject
     return 'JavaScript function for ${dartClosure.toString()}';
   }
 }
+
+/// Interceptor for JavaScript BigInt primitive values, i.e. values `x` for
+/// which `typeof x == "bigint"`.
+final class JavaScriptBigInt extends Interceptor {
+  const JavaScriptBigInt();
+
+  // JavaScript BigInt objects don't have any operations that look efficient
+  // enough to generate a good hash code.
+  //
+  // TODO(https://dartbug.com/53162): "bigint" primitive values might be used as
+  // keys without using the `hashCode`, but that will not help for compound hash
+  // values, e.g. produced by `Object.hash`.
+  int get hashCode => 0;
+
+  /// Returns the result of the JavaScript BigInt's `toString` method.
+  String toString() => JS('String', 'String(#)', this);
+}
+
+/// Interceptor for JavaScript Symbol primitive values, i.e. values `x` for
+/// which `typeof x == "symbol"`.
+final class JavaScriptSymbol extends Interceptor {
+  const JavaScriptSymbol();
+
+  // It is not clear what to do for a Symbol's hashCode.  Registered Symbols
+  // [can't be keys of WeakMaps][1].  Using a property won't work because the
+  // property will be added to the ephmeral Object wrapper, either being an
+  // incorrect operation or an error in strict mode.
+  //
+  // TODO(https://dartbug.com/53162): "symbol" primitive values might be used as
+  // keys without using the `hashCode`, but that will not help for compound hash
+  // values, e.g. produced by `Object.hash`.
+  //
+  // [1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol#shared_symbols_in_the_global_symbol_registry
+  int get hashCode => 0;
+
+  /// Returns the result of the JavaScript Symbol's `toString` method.
+  String toString() => JS('String', 'String(#)', this);
+}

tests/web/native/javascript_bigint_test.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2023, 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 'native_testing.dart';
+
+import 'dart:_interceptors';
+
+dynamic makeBigIntDynamic(String name) native;
+JavaScriptBigInt makeBigInt(String name) native;
+
+void setup() {
+  JS('', r"""
+(function(){
+  self.makeBigInt = function(name){return BigInt(name)};
+  self.makeBigIntDynamic = function(name){return BigInt(name)};
+})()""");
+}
+
+main() {
+  nativeTesting();
+  setup();
+  const s = '9876543210000000000000123456789';
+
+  Expect.notEquals(s, makeBigInt(s));
+  Expect.notEquals(s, makeBigIntDynamic(s));
+
+  Expect.equals(s, makeBigInt(s).toString());
+  Expect.equals(s, makeBigIntDynamic(s).toString());
+  Expect.equals(s, '${makeBigInt(s)}');
+  Expect.equals(s, '${makeBigIntDynamic(s)}');
+}

tests/web/native/javascript_symbol_test.dart

@@ -0,0 +1,31 @@
+// Copyright (c) 2023, 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 'native_testing.dart';
+
+import 'dart:_interceptors';
+
+dynamic makeSymbolDynamic(String name) native;
+JavaScriptSymbol makeSymbol(String name) native;
+
+void setup() {
+  JS('', r"""
+(function(){
+  self.makeSymbol = function(name){return Symbol(name)};
+  self.makeSymbolDynamic = function(name){return Symbol(name)};
+})()""");
+}
+
+main() {
+  nativeTesting();
+  setup();
+
+  Expect.notEquals('Symbol(foo)', makeSymbol('foo'));
+  Expect.notEquals('Symbol(foo)', makeSymbolDynamic('foo'));
+
+  Expect.equals('Symbol(foo)', makeSymbol('foo').toString());
+  Expect.equals('Symbol(foo)', makeSymbolDynamic('foo').toString());
+  Expect.equals('Symbol(foo)', '${makeSymbol('foo')}');
+  Expect.equals('Symbol(foo)', '${makeSymbolDynamic('foo')}');
+}