feat: Map/Set 支持 for-of 迭代与 entries/values/keys（内部槽方式）

crates/oxide_builtins/src/iterator.rs

@@ -74,7 +74,7 @@ pub fn iterator_wrapper_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult
 }
 
 fn get_iterator<H: VmHost>(vm: &mut H, value: JsValue) -> Result<JsValue, JsValue> {
-    if value.is_string() || is_array_value(value) {
+    if value.is_string() || is_array_value(value) || is_map_value(value) || is_set_value(value) {
         return Ok(value);
     }
 
@@ -115,6 +115,14 @@ fn next_array_like<H: VmHost>(vm: &mut H, wrapper: &mut JsObject, inner: JsValue
         return Some(make_iter_result(vm, JsValue::undefined(), true));
     }
 
+    // for-of loop default iterators: Map yields [key, value] entries, Set yields values.
+    if is_map_value(inner) {
+        return Some(map_set_step(vm, wrapper, inner, index_si, MapSetMode::MapEntries));
+    }
+    if is_set_value(inner) {
+        return Some(map_set_step(vm, wrapper, inner, index_si, MapSetMode::SetValues));
+    }
+
     None
 }
 
@@ -169,3 +177,143 @@ fn is_callable(value: JsValue) -> bool {
     let ptr = value.as_js_object_ptr();
     !ptr.is_null() && unsafe { &*ptr }.is_function()
 }
+
+fn is_map_value(value: JsValue) -> bool {
+    if !value.is_object() {
+        return false;
+    }
+    let ptr = value.as_js_object_ptr();
+    !ptr.is_null() && unsafe { &*ptr }.is_map()
+}
+
+fn is_set_value(value: JsValue) -> bool {
+    if !value.is_object() {
+        return false;
+    }
+    let ptr = value.as_js_object_ptr();
+    !ptr.is_null() && unsafe { &*ptr }.is_set()
+}
+
+fn make_map_set_pair<H: VmHost>(vm: &mut H, a: JsValue, b: JsValue) -> JsValue {
+    let array_proto = vm.session().builtin_world().array_proto.as_ptr() as *mut JsObject;
+    let pair = vm.alloc_object(JsObject::new_array(
+        EMPTY_SHAPE_ID,
+        JsValue::from_js_object(array_proto),
+        2,
+        vm.epoch().bump(),
+    ));
+    // SAFETY: pair is a freshly allocated array JsObject in the current epoch.
+    unsafe {
+        (*pair).set_prop_at(0, a);
+        (*pair).set_prop_at(1, b);
+        (*pair).set_prop_count(2);
+    }
+    JsValue::from_js_object(pair)
+}
+
+#[derive(Clone, Copy)]
+enum MapSetMode {
+    MapEntries,
+    MapValues,
+    MapKeys,
+    SetEntries,
+    SetValues,
+}
+
+/// Advance a Map/Set iterator wrapper one step, yielding the {value, done} result for
+/// the requested mode. Entries live in the indexmap stored in the collection's
+/// native-data slot; the (a, b) pair is copied out before any allocation so no borrow
+/// of the native collection is held across a `vm` call.
+fn map_set_step<H: VmHost>(
+    vm: &mut H, wrapper: &mut JsObject, inner: JsValue, index_si: u32, mode: MapSetMode,
+) -> JsValue {
+    let index = current_index(vm, wrapper, index_si);
+    let is_map = matches!(mode, MapSetMode::MapEntries | MapSetMode::MapValues | MapSetMode::MapKeys);
+    let entry: Option<(JsValue, JsValue)> = unsafe {
+        let obj_ptr = inner.as_js_object_ptr();
+        if obj_ptr.is_null() {
+            None
+        } else if is_map {
+            let p = (*obj_ptr).native_data() as *const crate::map::MapInner;
+            if p.is_null() {
+                None
+            } else {
+                (*p).get_index(index).map(|(key, value)| (key.0, *value))
+            }
+        } else {
+            let p = (*obj_ptr).native_data() as *const crate::set::SetInner;
+            if p.is_null() {
+                None
+            } else {
+                (*p).get_index(index).map(|elem| (elem.0, elem.0))
+            }
+        }
+    };
+
+    match entry {
+        Some((a, b)) => {
+            vm.set_or_create_prop_value(wrapper, index_si, JsValue::int((index + 1) as i32));
+            let value = match mode {
+                MapSetMode::MapEntries | MapSetMode::SetEntries => make_map_set_pair(vm, a, b),
+                MapSetMode::MapValues => b,
+                MapSetMode::MapKeys | MapSetMode::SetValues => a,
+            };
+            make_iter_result(vm, value, false)
+        }
+        None => make_iter_result(vm, JsValue::undefined(), true),
+    }
+}
+
+fn map_set_next_dispatch<H: VmHost>(vm: &mut H, args: &[u8], mode: MapSetMode) -> NativeResult {
+    let this_val = vm.reg(if args.is_empty() { 0 } else { args[0] });
+    if !this_val.is_object() {
+        return NativeResult::Err(crate::error::create_type_error(vm, "iterator next called on non-object"));
+    }
+    let wrapper = unsafe { &mut *this_val.as_js_object_ptr() };
+    let inner_si = vm.kernel_core().perm_interner().intern(INNER_PROP).0;
+    let index_si = vm.kernel_core().perm_interner().intern(INDEX_PROP).0;
+    let inner = match vm.ordinary_get(wrapper, inner_si, this_val) {
+        Ok(inner) if !inner.is_undefined() => inner,
+        _ => return NativeResult::Err(crate::error::create_type_error(vm, "iterator has no inner collection")),
+    };
+    NativeResult::Ok(map_set_step(vm, wrapper, inner, index_si, mode))
+}
+
+pub(crate) fn map_entries_iter_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
+    map_set_next_dispatch::<H>(vm, args, MapSetMode::MapEntries)
+}
+
+pub(crate) fn map_values_iter_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
+    map_set_next_dispatch::<H>(vm, args, MapSetMode::MapValues)
+}
+
+pub(crate) fn map_keys_iter_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
+    map_set_next_dispatch::<H>(vm, args, MapSetMode::MapKeys)
+}
+
+pub(crate) fn set_values_iter_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
+    map_set_next_dispatch::<H>(vm, args, MapSetMode::SetValues)
+}
+
+pub(crate) fn set_entries_iter_next<H: VmHost>(vm: &mut H, args: &[u8]) -> NativeResult {
+    map_set_next_dispatch::<H>(vm, args, MapSetMode::SetEntries)
+}
+
+/// Build an iterator wrapper whose `next` delegates to a caller-supplied mode-specific
+/// native function. Mirrors `make_iterator_for_value` but lets Map/Set prototype methods
+/// pick the values/keys/entries variant.
+pub(crate) fn make_mode_iterator<H: VmHost>(vm: &mut H, inner: JsValue, next_fn: *const ()) -> JsValue {
+    let object_proto = vm.session().builtin_world().object_proto.as_ptr() as *mut JsObject;
+    let wrapper = vm
+        .epoch()
+        .alloc(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::from_js_object(object_proto)));
+    let inner_si = vm.kernel_core().perm_interner().intern(INNER_PROP).0;
+    let index_si = vm.kernel_core().perm_interner().intern(INDEX_PROP).0;
+    let next_si = vm.kernel_core().perm_interner().intern("next").0;
+    let wrapper_obj = unsafe { &mut *wrapper };
+    vm.set_or_create_prop_value(wrapper_obj, inner_si, inner);
+    vm.set_or_create_prop_value(wrapper_obj, index_si, JsValue::int(0));
+    let next = make_native_function(vm, "next", next_fn, 0);
+    vm.set_or_create_prop_value(wrapper_obj, next_si, next);
+    JsValue::from_js_object(wrapper)
+}