fix(date): brand-check this on Date.prototype getters (reflective dispatch)

crates/perry-runtime/src/object/date_proto_thunks.rs

@@ -0,0 +1,114 @@
+//! `Date.prototype` getter thunks with a `this` brand check.
+//!
+//! The instance fast path (`d.getFullYear()`) is lowered directly by codegen:
+//! it reads the `DateCell` timestamp and calls the `js_date_get_*` helpers, so
+//! it never touches these thunks. But `Date.prototype.getFullYear` is also a
+//! plain value — `Date.prototype.getFullYear.call(x)`, `Reflect.apply`, method
+//! extraction — and on that reflective path the methods were installed as
+//! generic no-op thunks, so `getDate.call(realDate)` returned `[object Object]`
+//! and `getDate.call(nonDate)` silently produced garbage instead of throwing.
+//!
+//! Per spec each `Date.prototype` getter performs `thisTimeValue(this)`, which
+//! throws a `TypeError` when `this` is not an Object with a `[[DateValue]]`
+//! slot. These thunks read the `IMPLICIT_THIS` receiver (set by the
+//! `.call`/`.apply` dispatch), brand-check it via `is_date_value`, throw on
+//! mismatch, and otherwise dispatch to the SAME `js_date_get_*` helper the
+//! instance path uses — so reflective Date getter calls now also *work*.
+//!
+//! Installed onto `Date.prototype` by
+//! `global_this::populate_builtin_prototype_methods` (after the no-op block, so
+//! these real thunks overwrite the no-op getters; setters / `toX` formatters
+//! stay on the no-op path for now).
+
+use super::*;
+
+/// Resolve the `IMPLICIT_THIS` receiver to a Date time value, or throw a
+/// `TypeError` (`thisTimeValue` brand check) when it is not a Date.
+fn require_date_timestamp() -> f64 {
+    let this = f64::from_bits(IMPLICIT_THIS.with(|c| c.get()));
+    if crate::date::is_date_value(this) {
+        crate::date::date_cell_timestamp(this)
+    } else {
+        super::object_ops::throw_object_type_error(b"this is not a Date object.")
+    }
+}
+
+macro_rules! date_getter_thunk {
+    ($name:ident, $rt:path) => {
+        extern "C" fn $name(_closure: *const crate::closure::ClosureHeader) -> f64 {
+            $rt(require_date_timestamp())
+        }
+    };
+}
+
+date_getter_thunk!(date_get_time, crate::date::js_date_get_time);
+date_getter_thunk!(date_get_full_year, crate::date::js_date_get_full_year);
+date_getter_thunk!(date_get_month, crate::date::js_date_get_month);
+date_getter_thunk!(date_get_date, crate::date::js_date_get_date);
+date_getter_thunk!(date_get_hours, crate::date::js_date_get_hours);
+date_getter_thunk!(date_get_minutes, crate::date::js_date_get_minutes);
+date_getter_thunk!(date_get_seconds, crate::date::js_date_get_seconds);
+date_getter_thunk!(date_get_milliseconds, crate::date::js_date_get_milliseconds);
+date_getter_thunk!(date_get_day, crate::date::js_date_get_day);
+date_getter_thunk!(
+    date_get_utc_full_year,
+    crate::date::js_date_get_utc_full_year
+);
+date_getter_thunk!(date_get_utc_month, crate::date::js_date_get_utc_month);
+date_getter_thunk!(date_get_utc_date, crate::date::js_date_get_utc_date);
+date_getter_thunk!(date_get_utc_hours, crate::date::js_date_get_utc_hours);
+date_getter_thunk!(date_get_utc_minutes, crate::date::js_date_get_utc_minutes);
+date_getter_thunk!(date_get_utc_seconds, crate::date::js_date_get_utc_seconds);
+date_getter_thunk!(
+    date_get_utc_milliseconds,
+    crate::date::js_date_get_utc_milliseconds
+);
+date_getter_thunk!(date_get_utc_day, crate::date::js_date_get_utc_day);
+date_getter_thunk!(
+    date_get_timezone_offset,
+    crate::date::js_date_get_timezone_offset
+);
+
+/// Legacy `Date.prototype.getYear` — `getFullYear() - 1900` (NaN-preserving).
+extern "C" fn date_get_year(_closure: *const crate::closure::ClosureHeader) -> f64 {
+    let fy = crate::date::js_date_get_full_year(require_date_timestamp());
+    if fy.is_nan() {
+        fy
+    } else {
+        fy - 1900.0
+    }
+}
+
+/// Install the brand-checked `Date.prototype` getter thunks. Called from
+/// `global_this::populate_builtin_prototype_methods`'s `"Date"` arm AFTER the
+/// no-op block, so these overwrite the no-op getter entries.
+pub(crate) fn install_date_proto_getters(proto_obj: *mut ObjectHeader) {
+    if proto_obj.is_null() {
+        return;
+    }
+    let methods: &[(&str, *const u8)] = &[
+        ("getTime", date_get_time as *const u8),
+        ("valueOf", date_get_time as *const u8),
+        ("getFullYear", date_get_full_year as *const u8),
+        ("getMonth", date_get_month as *const u8),
+        ("getDate", date_get_date as *const u8),
+        ("getHours", date_get_hours as *const u8),
+        ("getMinutes", date_get_minutes as *const u8),
+        ("getSeconds", date_get_seconds as *const u8),
+        ("getMilliseconds", date_get_milliseconds as *const u8),
+        ("getDay", date_get_day as *const u8),
+        ("getUTCFullYear", date_get_utc_full_year as *const u8),
+        ("getUTCMonth", date_get_utc_month as *const u8),
+        ("getUTCDate", date_get_utc_date as *const u8),
+        ("getUTCHours", date_get_utc_hours as *const u8),
+        ("getUTCMinutes", date_get_utc_minutes as *const u8),
+        ("getUTCSeconds", date_get_utc_seconds as *const u8),
+        ("getUTCMilliseconds", date_get_utc_milliseconds as *const u8),
+        ("getUTCDay", date_get_utc_day as *const u8),
+        ("getTimezoneOffset", date_get_timezone_offset as *const u8),
+        ("getYear", date_get_year as *const u8),
+    ];
+    for (name, ptr) in methods.iter().copied() {
+        super::global_this::install_proto_method(proto_obj, name, ptr, 0);
+    }
+}

crates/perry-runtime/src/object/global_this.rs

@@ -4067,6 +4067,12 @@ fn populate_builtin_prototype_methods(builtin_name: &str, proto_obj: *mut Object
                 ],
             );
             install_noop_proto_methods(proto_obj, OBJECT_PROTO_METHODS);
+            // Overwrite the no-op getter entries with brand-checking thunks so
+            // `Date.prototype.getX.call(this)` performs `thisTimeValue(this)`
+            // (TypeError on a non-Date receiver) and dispatches correctly.
+            // MUST run after the OBJECT_PROTO_METHODS block, which would
+            // otherwise re-clobber `valueOf` with the generic Object no-op.
+            date_proto_thunks::install_date_proto_getters(proto_obj);
             install_proto_method(
                 proto_obj,
                 "isPrototypeOf",

crates/perry-runtime/src/object/mod.rs

@@ -30,6 +30,7 @@ mod class_registry;
 mod collection_proto_thunks;
 mod data_view_registry;
 mod dataview_proto_thunks;
+mod date_proto_thunks;
 mod delete_rest;
 mod descriptors;
 mod field_get_set;

crates/perry-stdlib/src/webcrypto/jwk.rs

@@ -494,10 +494,7 @@ pub unsafe extern "C" fn js_webcrypto_export_key(format_bits: f64, key_bits: f64
             let encoded = base64::engine::general_purpose::URL_SAFE_NO_PAD.encode(&key_bytes);
             let field_count = if matches!(
                 mat.algo,
-                KeyAlgo::ChaCha20Poly1305
-                    | KeyAlgo::Kmac128
-                    | KeyAlgo::Kmac256
-                    | KeyAlgo::AesOcb
+                KeyAlgo::ChaCha20Poly1305 | KeyAlgo::Kmac128 | KeyAlgo::Kmac256 | KeyAlgo::AesOcb
             ) {
                 3
             } else {