Allow to wrap arbitrary Ruby Object by JS's RbValue

When passing a non-interoperated Ruby Object like `Object` to JS method
from Ruby world, the object has to be JS object.
This patch provides a way to wrap a Ruby object by `RbValue`, which is a
Ruby object representation in JS world.

Author: kateinoigakukun

ext/js/bindgen/rb-js-abi-host.wit

@@ -7,6 +7,7 @@ global-this: function() -> js-abi-value
 int-to-js-number: function(value: s32) -> js-abi-value
 string-to-js-string: function(value: string) -> js-abi-value
 bool-to-js-bool: function(value: bool) -> js-abi-value
+rb-object-to-js-rb-value: function(raw-rb-abi-value: u32) -> js-abi-value
 
 js-value-to-string: function(value: js-abi-value) -> string
 

ext/js/js-core.c

@@ -102,9 +102,10 @@ static VALUE _rb_js_is_js(VALUE _, VALUE obj) {
  *  Try to convert the given object to a JS::Object using <code>to_js</code>
  *  method. Returns <code>nil</code> if the object cannot be converted.
  *
- *   p JS.try_convert(1)          # => 1
- *   p JS.try_convert("foo")      # => "foo"
- *   p JS.try_convert(Object.new) # => nil
+ *   p JS.try_convert(1)                           # => JS::Object
+ *   p JS.try_convert("foo")                       # => JS::Object
+ *   p JS.try_convert(Object.new)                  # => nil
+ *   p JS.try_convert(JS::Object.wrap(Object.new)) # => JS::Object
  */
 VALUE _rb_js_try_convert(VALUE klass, VALUE obj) {
   if (_rb_js_is_js(klass, obj)) {
@@ -242,6 +243,17 @@ static VALUE _rb_js_export_to_js(VALUE obj) {
   return Qnil;
 }
 
+
+/*
+ * call-seq:
+ *   JS::Object.wrap(obj) -> JS::Object
+ *
+ *  Returns +obj+ wrapped by JS class RbValue.
+ */
+static VALUE _rb_js_obj_wrap(VALUE obj, VALUE wrapping) {
+  return jsvalue_s_new(rb_js_abi_host_rb_object_to_js_rb_value((uint32_t)wrapping));
+}
+
 /*
  * call-seq:
  *   to_js -> JS::Object
@@ -306,6 +318,7 @@ void Init_js() {
   rb_define_method(rb_cJS_Object, "call", _rb_js_obj_call, -1);
   rb_define_method(rb_cJS_Object, "__export_to_js", _rb_js_export_to_js, 0);
   rb_define_method(rb_cJS_Object, "inspect", _rb_js_obj_inspect, 0);
+  rb_define_singleton_method(rb_cJS_Object, "wrap", _rb_js_obj_wrap, 1);
 
   rb_define_method(rb_cInteger, "to_js", _rb_js_integer_to_js, 0);
   rb_define_method(rb_cString, "to_js", _rb_js_string_to_js, 0);

packages/npm-packages/ruby-wasm-wasi/src/index.ts

@@ -72,7 +72,8 @@ export class RubyVM {
           return Function(code)();
         },
         isJs: (value) => {
-          return value == null || !(value instanceof RbValue);
+          // Just for compatibility with the old JS API
+          return true;
         },
         globalThis: () => {
           if (typeof globalThis !== "undefined") {
@@ -93,6 +94,10 @@ export class RubyVM {
         boolToJsBool: (value) => {
           return value;
         },
+        rbObjectToJsRbValue: (rawRbAbiValue) => {
+            const abiValue = new (RbAbi.RbAbiValue as any)(rawRbAbiValue, this.guest);
+            return new RbValue(abiValue, this, this.privateObject());
+        },
         jsValueToString: (value) => {
           return value.toString();
         },
@@ -172,7 +177,11 @@ export class RubyVM {
    *
    */
   eval(code: string): RbValue {
-    return evalRbCode(this, { exporter: this.exporter, exceptionFormatter: this.exceptionFormatter }, code);
+    return evalRbCode(this, this.privateObject(), code);
+  }
+
+  private privateObject(): RubyVMPrivate {
+    return { exporter: this.exporter, exceptionFormatter: this.exceptionFormatter }
   }
 }
 

packages/npm-packages/ruby-wasm-wasi/test/js_from_rb.test.ts

@@ -147,4 +147,22 @@ describe("Manipulation of JS from Ruby", () => {
       `);
     expect(result.toJS()).toEqual(expected);
   });
+
+  test("Wrap arbitrary Ruby object to JS::Object", async () => {
+    const vm = await initRubyVM();
+    const results = vm.eval(`
+      require "js"
+      intrinsics = JS.eval(<<-JS)
+        return {
+          identity(v) { return v }
+        }
+      JS
+      o1 = Object.new
+      o1_clone = intrinsics.call(:identity, JS::Object.wrap(o1))
+      [o1.object_id, o1_clone.call("call", "object_id").inspect]
+    `);
+    const o1 = results.call("at", vm.eval("0"));
+    const o1Clone = results.call("at", vm.eval("1"));
+    expect(o1.toString()).toEqual(o1Clone.toString());
+  });
 });