feat: 迭代器包装器零参转发加关闭期惰性return读取

Cargo.lock

@@ -1160,7 +1160,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_builtins"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "chrono",
  "fast-float",
@@ -1185,7 +1185,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_bytecode"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "num-bigint",
  "oxide_log",
@@ -1193,7 +1193,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_cfg"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_emit",
@@ -1204,7 +1204,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_cli"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "ansi_term",
  "bumpalo",
@@ -1226,7 +1226,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_code_cache"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "lru",
  "oxide_bytecode",
@@ -1235,7 +1235,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_compiler"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1255,7 +1255,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_dce"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1269,7 +1269,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_emit"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "num-bigint",
  "oxc_allocator",
@@ -1284,7 +1284,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_engine"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_compiler",
@@ -1296,7 +1296,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_ir"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_log",
@@ -1305,7 +1305,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_kernel"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "bumpalo",
  "dashmap",
@@ -1319,7 +1319,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_liveness"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1331,7 +1331,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_log"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "tracing",
  "tracing-appender",
@@ -1340,7 +1340,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_parser"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxc_allocator",
  "oxc_ast",
@@ -1355,7 +1355,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_regalloc"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1371,7 +1371,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_runtime_api"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "num-bigint",
  "num-traits",
@@ -1384,7 +1384,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_test262"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "oxide_bytecode",
  "oxide_compiler",
@@ -1402,7 +1402,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_types"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "bumpalo",
  "dashmap",
@@ -1415,7 +1415,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_vm"
-version = "0.13.27"
+version = "0.13.28"
 dependencies = [
  "bumpalo",
  "chrono",

Cargo.toml

@@ -23,7 +23,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.13.27"
+version = "0.13.28"
 edition = "2021"
 license = "MIT"
 rust-version = "1.80"

crates/oxide_builtins/src/iterator.rs

@@ -1230,11 +1230,13 @@ pub(crate) fn try_make_iterator_inner_proto<H: VmHost>(
 ///    `@@iterator` 返回自身）。
 /// 2. 写入 `__inner__`/`__index__` 槽；鸭子回退路径把创建时读到的 `next` 闭包
 ///    缓存进 `__next__` 槽，消费期直读槽不重触发 getter。
-/// 3. 挂 `next` 方法；`bind_return` 且内层有可调用 `return` 时条件暴露 `return`。
+/// 3. 挂 `next` 方法；`bind_return` 且内层是对象时恒挂 `return` 方法
+///    （内层 return 在关闭期惰性读取，构造期不触碰其 getter）。
 ///
 /// # 边界
 /// - `bind_return` 控制是否暴露 `return` 方法（for-of/解构的 IteratorClose 需要，
-///   `yield*` 委托不需要且须避免创建时访问内层 return getter）。
+///   `yield*` 委托不需要）；内层 return 一律关闭期惰性 GetMethod，构造期不触碰
+///   其 getter，getter 抛错与不可调用判定在关闭期发生。
 /// - 本函数不解析 `@@iterator`：`get_iterator` 派生内层，或默认迭代器函数直接以
 ///   已 ToString 的串为内层构造（其语义只由 `this` 决定，与属性表状态解耦）。
 pub(crate) fn build_iterator_wrapper<H: VmHost>(
@@ -1264,22 +1266,28 @@ pub(crate) fn build_iterator_wrapper<H: VmHost>(
     let wrapper_next = make_native_function(vm, "next", iterator_wrapper_next::<H> as *const (), 0);
     vm.set_or_create_prop_value(wrapper_obj, next_si, wrapper_next);
 
-    // for-of/解构的 IteratorClose 需要 return 方法：条件暴露（内层有可调用 return 时）。
+    // for-of/解构的 IteratorClose 需要 return 方法：bind_return 且内层是对象时恒挂，
+    // 内层 return 由包装器 return 方法在关闭期惰性 GetMethod（getter 抛错传播、
+    // 不可调用抛 TypeError、undefined/null 无操作）。
     // `yield*` 委托（bind_return=false）不绑定，转发时对内层延迟 GetMethod。
     let return_si = vm.perm_intern("return");
     if bind_return && inner.is_object() {
-        let inner_obj = unsafe { &*inner.as_js_object_ptr() };
-        if let Ok(return_fn) = vm.ordinary_get(inner_obj, return_si, inner) {
-            if is_callable(return_fn) {
-                let wrapper_return = make_native_function(vm, "return", iterator_wrapper_return::<H> as *const (), 0);
-                vm.set_or_create_prop_value(wrapper_obj, return_si, wrapper_return);
-            }
-        }
+        let wrapper_return = make_native_function(vm, "return", iterator_wrapper_return::<H> as *const (), 0);
+        vm.set_or_create_prop_value(wrapper_obj, return_si, wrapper_return);
     }
 
     JsValue::from_js_object(wrapper)
 }
 
+/// 迭代器包装器的 `return` 方法：关闭期惰性读取内层 `return`（完整 GetMethod
+/// 步序）并转发调用，默认零参。
+///
+/// # 步骤
+/// 1. 读 `__inner__` 槽；this 非对象或槽缺失/非对象时返回 undefined（无操作）。
+/// 2. GetMethod(inner, "return")：getter 抛错透传原异常；undefined/null 返回空
+///    对象（无操作，使调用方步 7 的对象校验通过）；已定义不可调用值抛 TypeError。
+/// 3. 调用方显式传参时转发该实参（Iterator.prototype.return 的 return(v) 语义），
+///    否则零参调用（IteratorClose 步 4c）；结果原样返回，步 7 由调用方执行。
 fn iterator_wrapper_return<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
     let this_val = vm.reg(if args.is_empty() { 0 } else { args[0] });
     if !this_val.is_object() {
@@ -1291,16 +1299,29 @@ fn iterator_wrapper_return<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
         Ok(inner) if inner.is_object() => inner,
         _ => return NativeResult::Ok(JsValue::undefined()),
     };
-    // 延迟 GetMethod：内层无 return 方法时返回 undefined（IteratorClose 跳过）。
+    // 延迟 GetMethod：内层 return 在关闭期读取，getter 抛错透传原异常。
     let inner_obj = unsafe { &*inner.as_js_object_ptr() };
     let return_si = vm.perm_intern("return");
     let return_fn = match vm.ordinary_get(inner_obj, return_si, inner) {
         Ok(f) if is_callable(f) => f,
-        _ => return NativeResult::Ok(JsValue::undefined()),
+        // undefined/null：GetMethod 返回 unused，无操作，返空对象使调用方步 7 通过。
+        Ok(f) if f.is_undefined() || f.is_null() => {
+            let object_proto = vm.builtin_proto(ProtoKind::ObjectProto);
+            let obj = vm.alloc_object(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::from_js_object(object_proto)));
+            return NativeResult::Ok(JsValue::from_js_object(obj));
+        }
+        // 已定义不可调用值：GetMethod 抛 TypeError。
+        Ok(_) => return NativeResult::Err(crate::error::create_type_error(vm, "iterator return is not a function")),
+        Err(err) => return NativeResult::Err(engine_error(vm, &err)),
     };
-    // 转发调用实参（`yield*` 委托的 return(v) 语义），缺省为 undefined。
-    let arg = if args.len() > 1 { vm.reg(args[1]) } else { JsValue::undefined() };
-    match vm.call_function_sync(return_fn, inner, &[arg]) {
+    // 默认零参（IteratorClose 步 4c）；调用方显式传参时转发（Iterator.prototype.return
+    // 的 return(v) 语义）。结果原样返回，步 7 由调用方 IteratorClose 执行。
+    let result = if args.len() > 1 {
+        vm.call_function_sync(return_fn, inner, &[vm.reg(args[1])])
+    } else {
+        vm.call_function_sync(return_fn, inner, &[])
+    };
+    match result {
         Ok(result) => NativeResult::Ok(result),
         Err(err) => match vm.take_uncaught_value() {
             Some(original) => NativeResult::Err(original),
@@ -1363,9 +1384,14 @@ pub fn iterator_wrapper_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult
                 }
             }
         };
-        // 转发调用实参（`yield*` 委托的 next(v) 语义），缺省为 undefined。
-        let arg = if args.len() > 1 { vm.reg(args[1]) } else { JsValue::undefined() };
-        return match vm.call_function_sync(next, inner, &[arg]) {
+        // 默认零参（IteratorNext 步 4 零参调用）；调用方显式传参时转发（Iterator.
+        // prototype.next 的 next(v) 语义）。
+        let result = if args.len() > 1 {
+            vm.call_function_sync(next, inner, &[vm.reg(args[1])])
+        } else {
+            vm.call_function_sync(next, inner, &[])
+        };
+        return match result {
             Ok(result) => NativeResult::Ok(result),
             // 透传原始抛出的值（任意类型）而非重新包装成 TypeError，
             // 使外围 try/catch 能看到真正的错误。

crates/oxide_builtins/tests/iterator_wrapper_tests.rs

@@ -0,0 +1,151 @@
+//! 迭代器包装器（make_iterator_for_value 建出的统一迭代器对象）的
+//! return/next 转发语义测试：零参转发、关闭期惰性 GetMethod（getter 抛错
+//! 传播、不可调用 TypeError、null 无操作）、构造期不触碰内层 return getter。
+
+use std::sync::Arc;
+
+use oxide_compiler::compiler::Compiler;
+use oxide_compiler::DefaultCompilerService;
+use oxide_parser::Allocator;
+use oxide_vm::vm::Vm;
+
+fn eval(source: &str) -> String {
+    let allocator = Allocator::default();
+    let program = match oxide_parser::parse(&allocator, source) {
+        Ok(p) => p,
+        Err(e) => return format!("parse error: {}", e[0].message),
+    };
+    let module = match Compiler::new().compile(&program) {
+        Ok(m) => m,
+        Err(e) => return format!("compile error: {e}"),
+    };
+    let mut vm = Vm::new();
+    vm.set_compiler_service(Arc::new(DefaultCompilerService));
+    match vm.run(&Arc::new(module)) {
+        Ok(result) => format!("{result}"),
+        Err(e) => format!("vm error: {e}"),
+    }
+}
+
+#[test]
+fn wrapper_return_forwards_zero_args() {
+    // 包装器 return 默认零参转发内层 return（IteratorClose 步 4c）。
+    assert_eq!(
+        eval(
+            "var it={next:function(){return {value:1,done:false};},\
+             return:function(){globalThis.n=arguments.length;return {};}};\
+             for(var v of it){break;}globalThis.n===0"
+        ),
+        "true",
+        "wrapper return must call inner return with zero arguments"
+    );
+}
+
+#[test]
+fn wrapper_next_forwards_zero_args() {
+    // 包装器 next 默认零参转发内层 next（IteratorNext 步 4）。
+    assert_eq!(
+        eval(
+            "var it={next:function(){globalThis.n=arguments.length;\
+             return {value:1,done:true};}};\
+             for(var v of it){}globalThis.n===0"
+        ),
+        "true",
+        "wrapper next must call inner next with zero arguments"
+    );
+}
+
+#[test]
+fn wrapper_return_getter_throw_propagates_on_normal_close() {
+    // 正常完成关闭时，内层 return getter 抛错必须传播（关闭期惰性 GetMethod）。
+    assert_eq!(
+        eval(
+            "var it={next:function(){return {value:1,done:false};},\
+             get return(){throw new TypeError('getter');}};\
+             globalThis.r=false;\
+             try{for(var v of it){break;}}\
+             catch(e){globalThis.r=(e.name==='TypeError'&&e.message==='getter');}\
+             globalThis.r"
+        ),
+        "true",
+        "getter throw on inner return must propagate on normal-completion close"
+    );
+}
+
+#[test]
+fn wrapper_return_non_callable_throws_type_error() {
+    // 正常完成关闭时，内层 return 为已定义不可调用值必须抛 TypeError。
+    assert_eq!(
+        eval(
+            "var it={next:function(){return {value:1,done:false};},return:1};\
+             globalThis.r=false;\
+             try{for(var v of it){break;}}\
+             catch(e){globalThis.r=(e instanceof TypeError);}\
+             globalThis.r"
+        ),
+        "true",
+        "defined non-callable inner return must throw TypeError on close"
+    );
+}
+
+#[test]
+fn wrapper_return_null_is_noop() {
+    // 内层 return 为 null 时关闭无操作（GetMethod 步 2 返回 unused）。
+    assert_eq!(
+        eval(
+            "var it={next:function(){return {value:1,done:false};},return:null};\
+             var threw=false;\
+             try{for(var v of it){break;}}catch(e){threw=true;}\
+             threw===false"
+        ),
+        "true",
+        "null inner return must be a no-op on close"
+    );
+}
+
+#[test]
+fn wrapper_return_getter_throw_suppressed_on_throw_close() {
+    // throw 完成关闭时，内层 return getter 抛错被在途异常替代（原异常胜出）。
+    assert_eq!(
+        eval(
+            "var it={next:function(){return {value:1,done:false};},\
+             get return(){throw new TypeError('getter');}};\
+             globalThis.r=false;\
+             try{for(var v of it){throw new Error('body');}}\
+             catch(e){globalThis.r=(e.name==='Error'&&e.message==='body');}\
+             globalThis.r"
+        ),
+        "true",
+        "getter throw on inner return must be suppressed when close follows a throw"
+    );
+}
+
+#[test]
+fn wrapper_return_not_eagerly_bound_at_construction() {
+    // 构造包装器时不得触碰内层 return getter（计数时点在关闭期）。
+    assert_eq!(
+        eval(
+            "var count=0;\
+             var it={next:function(){return {value:1,done:false};},\
+             get return(){count++;throw new TypeError('getter');}};\
+             var w=Iterator.from(it);count===0"
+        ),
+        "true",
+        "wrapper construction must not touch the inner return getter"
+    );
+}
+
+#[test]
+fn wrapper_return_getter_called_once_at_close() {
+    // 内层 return getter 在关闭期恰好被调用一次。
+    assert_eq!(
+        eval(
+            "var count=0;\
+             var it={next:function(){return {value:1,done:false};},\
+             get return(){count++;return function(){return {};};}};\
+             for(var v of it){break;}count===1"
+        ),
+        "true",
+        "inner return getter must be invoked exactly once, at close"
+    );
+}