wrap dart object to js.

CHANGELOG.md

@@ -6,6 +6,11 @@
  * @LastEditTime: 2020-12-02 11:36:40
 -->
 
+## 0.2.4
+
+* wrap dart object to js.
+* fix stack overflow when use jsCall nesting.
+
 ## 0.2.3
 
 * fix compiler error in windows release.

README.md

@@ -53,8 +53,9 @@ Data conversion between dart and js are implemented as follow:
 | Map                                                 | Object             |
 | JSFunction(...args) <br> IsolateJSFunction(...args) | function(....args) |
 | Future                                              | Promise            |
+| Object                                              | DartObject         |
 
-**notice:** `function` can only be sent from js to dart.
+**notice:** `function` can only be sent from js to dart. `DartObject` can only be used in `moduleHandler`.
 
 ### Invoke dart function
 

cxx/ffi.cpp

@@ -105,8 +105,11 @@ extern "C"
 
   DLLEXPORT JSValue *jsEval(JSContext *ctx, const char *input, size_t input_len, const char *filename, int32_t eval_flags)
   {
-    JS_ResetStackTop(JS_GetRuntime(ctx));
-    return new JSValue(JS_Eval(ctx, input, input_len, filename, eval_flags));
+    JSRuntime *rt = JS_GetRuntime(ctx);
+    uint8_t *stack_top = JS_SetStackTop(rt, 0);
+    JSValue *ret = new JSValue(JS_Eval(ctx, input, input_len, filename, eval_flags));
+    JS_SetStackTop(rt, stack_top);
+    return ret;
   }
 
   DLLEXPORT int32_t jsValueGetTag(JSValue *val)
@@ -283,8 +286,11 @@ extern "C"
   DLLEXPORT JSValue *jsCall(JSContext *ctx, JSValueConst *func_obj, JSValueConst *this_obj,
                             int32_t argc, JSValueConst *argv)
   {
-    JS_ResetStackTop(JS_GetRuntime(ctx));
-    return new JSValue(JS_Call(ctx, *func_obj, *this_obj, argc, argv));
+    JSRuntime *rt = JS_GetRuntime(ctx);
+    uint8_t *stack_top = JS_SetStackTop(rt, 0);
+    JSValue *ret = new JSValue(JS_Call(ctx, *func_obj, *this_obj, argc, argv));
+    JS_SetStackTop(rt, stack_top);
+    return ret;
   }
 
   DLLEXPORT int32_t jsIsException(JSValueConst *val)
@@ -299,9 +305,11 @@ extern "C"
 
   DLLEXPORT int32_t jsExecutePendingJob(JSRuntime *rt)
   {
-    JS_ResetStackTop(rt);
+    uint8_t *stack_top = JS_SetStackTop(rt, 0);
     JSContext *ctx;
-    return JS_ExecutePendingJob(rt, &ctx);
+    int ret = JS_ExecutePendingJob(rt, &ctx);
+    JS_SetStackTop(rt, stack_top);
+    return ret;
   }
 
   DLLEXPORT JSValue *jsNewPromiseCapability(JSContext *ctx, JSValue *resolving_funcs)

example/pubspec.lock

@@ -82,7 +82,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.2.3"
+    version: "0.2.4"
   flutter_test:
     dependency: "direct dev"
     description: flutter

lib/ffi.dart

@@ -113,6 +113,7 @@ class RuntimeOpaque {
   List<JSRef> ref = [];
   ReceivePort port;
   Future Function(Pointer) promiseToFuture;
+  Pointer Function(Object) objectWrapper;
 }
 
 final Map<Pointer, RuntimeOpaque> runtimeOpaques = Map();

lib/wrapper.dart

@@ -37,6 +37,26 @@ class JSRefValue implements JSRef {
   }
 }
 
+class DartObject implements JSRef {
+  Object obj;
+  Pointer ctx;
+  DartObject(this.ctx, this.obj) {
+    runtimeOpaques[jsGetRuntime(ctx)]?.ref?.add(this);
+  }
+
+  static DartObject fromAddress(Pointer ctx, int val) {
+    return runtimeOpaques[jsGetRuntime(ctx)]?.ref?.firstWhere(
+          (e) => identityHashCode(e) == val,
+          orElse: null,
+        );
+  }
+
+  @override
+  void release() {
+    ctx = null;
+  }
+}
+
 class JSPromise extends JSRefValue {
   Completer completer;
   JSPromise(Pointer ctx, Pointer val, this.completer) : super(ctx, val);
@@ -123,6 +143,7 @@ String parseJSException(Pointer ctx, {Pointer e}) {
 }
 
 Pointer dartToJs(Pointer ctx, dynamic val, {Map<dynamic, dynamic> cache}) {
+  if (val == null) return jsUNDEFINED();
   if (val is Future) {
     var resolvingFunc = allocate<Uint8>(count: sizeOfJSValue * 2);
     var resolvingFunc2 =
@@ -195,7 +216,7 @@ Pointer dartToJs(Pointer ctx, dynamic val, {Map<dynamic, dynamic> cache}) {
     }
     return ret;
   }
-  return jsUNDEFINED();
+  return runtimeOpaques[jsGetRuntime(ctx)]?.objectWrapper(val) ?? jsUNDEFINED();
 }
 
 dynamic jsToDart(Pointer ctx, Pointer val, {Map<int, dynamic> cache}) {
@@ -262,6 +283,10 @@ dynamic jsToDart(Pointer ctx, Pointer val, {Map<int, dynamic> cache}) {
         }
         jsFree(ctx, ptab.value);
         free(ptab);
+        final objHash = ret["__dart_obj_hash__"];
+        if (objHash is int) {
+          return DartObject.fromAddress(ctx, objHash)?.obj ?? ret;
+        }
         return ret;
       }
       break;
@@ -272,6 +297,9 @@ dynamic jsToDart(Pointer ctx, Pointer val, {Map<int, dynamic> cache}) {
 
 Pointer jsNewContextWithPromsieWrapper(Pointer rt) {
   var ctx = jsNewContext(rt);
+  final runtimeOpaque = runtimeOpaques[rt];
+  if (runtimeOpaque == null) throw Exception("Runtime has been released!");
+
   var jsPromiseWrapper = jsEval(
       ctx,
       """
@@ -290,17 +318,42 @@ Pointer jsNewContextWithPromsieWrapper(Pointer rt) {
         """,
       "<future>",
       JSEvalFlag.GLOBAL);
-  var promiseWrapper = JSRefValue(ctx, jsPromiseWrapper);
+  var jsObjectWrapper = jsEval(
+      ctx,
+      """
+        (objHash, type) => {
+            const ret = {
+              "__dart_obj_hash__": objHash,
+            };
+            ret.__proto__.toString = ()=>  "" + type;
+            return ret;
+        };
+        """,
+      "<future>",
+      JSEvalFlag.GLOBAL);
+  final promiseWrapper = JSRefValue(ctx, jsPromiseWrapper);
   jsFreeValue(ctx, jsPromiseWrapper);
-  runtimeOpaques[rt].promiseToFuture = (promise) {
+  final objectWrapper = JSRefValue(ctx, jsObjectWrapper);
+  jsFreeValue(ctx, jsObjectWrapper);
+  runtimeOpaque.promiseToFuture = (promise) {
     var completer = Completer();
     var wrapper = promiseWrapper.val;
     if (wrapper == null)
       completer.completeError(Exception("Runtime has been released!"));
     var jsPromise = jsCall(ctx, wrapper, null, [promise]);
-    runtimeOpaques[rt].ref.add(JSPromise(ctx, jsPromise, completer));
+    var wrapPromise = JSPromise(ctx, jsPromise, completer);
     jsFreeValue(ctx, jsPromise);
-    return completer.future;
+    return wrapPromise.completer.future;
+  };
+  runtimeOpaque.objectWrapper = (obj) {
+    var jsObjHash = jsNewInt64(ctx, identityHashCode(DartObject(ctx, obj)));
+    var jsTypeString = jsNewString(ctx, obj.toString());
+    var wrapper = objectWrapper.val;
+    if (wrapper == null) throw Exception("Runtime has been released!");
+    var ret = jsCall(ctx, wrapper, null, [jsObjHash, jsTypeString]);
+    jsFreeValue(ctx, jsObjHash);
+    jsFreeValue(ctx, jsTypeString);
+    return ret;
   };
 
   return ctx;

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_qjs
 description: This plugin is a simple js engine for flutter using the `quickjs` project. Plugin currently supports all the platforms except web!
-version: 0.2.3
+version: 0.2.4
 homepage: https://github.com/ekibun/flutter_qjs
 
 environment:

test/flutter_qjs_test.dart

@@ -98,19 +98,15 @@ void main() async {
     qjs.close();
   });
   test('jsToDart', () async {
-    await runZonedGuarded(() async {
-      final qjs = FlutterQjs(
-        methodHandler: myMethodHandler,
-        moduleHandler: (name) {
-          return "export default '${new DateTime.now()}'";
-        },
-      );
-      qjs.dispatch();
-      await testEvaluate(qjs);
-      qjs.close();
-    }, (e, stack) {
-      if (e is TestFailure) throw e;
-    });
+    final qjs = FlutterQjs(
+      methodHandler: myMethodHandler,
+      moduleHandler: (name) {
+        return "export default '${new DateTime.now()}'";
+      },
+    );
+    qjs.dispatch();
+    await testEvaluate(qjs);
+    qjs.close();
   });
   test('isolate', () async {
     await runZonedGuarded(() async {
@@ -123,9 +119,20 @@ void main() async {
       await testEvaluate(qjs);
       qjs.close();
     }, (e, stack) {
-      if (e is TestFailure) throw e;
+      if (!e.toString().startsWith("test Promise.reject")) throw e;
     });
   });
+  test('dart object', () async {
+    final qjs = FlutterQjs(
+      methodHandler: (method, args) {
+        return FlutterQjs();
+      },
+    );
+    qjs.dispatch();
+    var value = await qjs.evaluate("channel('channel', [])", name: "<eval>");
+    expect(value, isInstanceOf<FlutterQjs>(), reason: "dart object");
+    qjs.close();
+  });
   test('stack overflow', () async {
     final qjs = FlutterQjs();
     try {