void duk_hobject_enumerator_create(duk_context *ctx, duk_small_uint_t enum_flags) { duk_hthread *thr = (duk_hthread *) ctx; duk_hobject *enum_target; duk_hobject *curr; duk_hobject *res; #if defined(DUK_USE_ES6_PROXY) duk_hobject *h_proxy_target; duk_hobject *h_proxy_handler; duk_hobject *h_trap_result; #endif duk_uint_fast32_t i, len; /* used for array, stack, and entry indices */ DUK_ASSERT(ctx != NULL); DUK_DDD(DUK_DDDPRINT("create enumerator, stack top: %ld", (long) duk_get_top(ctx))); enum_target = duk_require_hobject(ctx, -1); DUK_ASSERT(enum_target != NULL); duk_push_object_internal(ctx); res = duk_require_hobject(ctx, -1); DUK_DDD(DUK_DDDPRINT("created internal object")); /* [enum_target res] */ /* Target must be stored so that we can recheck whether or not * keys still exist when we enumerate. This is not done if the * enumeration result comes from a proxy trap as there is no * real object to check against. */ duk_push_hobject(ctx, enum_target); duk_put_prop_stridx(ctx, -2, DUK_STRIDX_INT_TARGET); /* Initialize index so that we skip internal control keys. */ duk_push_int(ctx, DUK__ENUM_START_INDEX); duk_put_prop_stridx(ctx, -2, DUK_STRIDX_INT_NEXT); /* * Proxy object handling */ #if defined(DUK_USE_ES6_PROXY) if (DUK_LIKELY((enum_flags & DUK_ENUM_NO_PROXY_BEHAVIOR) != 0)) { goto skip_proxy; } if (DUK_LIKELY(!duk_hobject_proxy_check(thr, enum_target, &h_proxy_target, &h_proxy_handler))) { goto skip_proxy; } DUK_DDD(DUK_DDDPRINT("proxy enumeration")); duk_push_hobject(ctx, h_proxy_handler); if (!duk_get_prop_stridx(ctx, -1, DUK_STRIDX_ENUMERATE)) { /* No need to replace the 'enum_target' value in stack, only the * enum_target reference. This also ensures that the original * enum target is reachable, which keeps the proxy and the proxy * target reachable. We do need to replace the internal _target. */ DUK_DDD(DUK_DDDPRINT("no enumerate trap, enumerate proxy target instead")); DUK_DDD(DUK_DDDPRINT("h_proxy_target=%!O", (duk_heaphdr *) h_proxy_target)); enum_target = h_proxy_target; duk_push_hobject(ctx, enum_target); /* -> [ ... enum_target res handler undefined target ] */ duk_put_prop_stridx(ctx, -4, DUK_STRIDX_INT_TARGET); duk_pop_2(ctx); /* -> [ ... enum_target res ] */ goto skip_proxy; } /* [ ... enum_target res handler trap ] */ duk_insert(ctx, -2); duk_push_hobject(ctx, h_proxy_target); /* -> [ ... enum_target res trap handler target ] */ duk_call_method(ctx, 1 /*nargs*/); /* -> [ ... enum_target res trap_result ] */ h_trap_result = duk_require_hobject(ctx, -1); DUK_UNREF(h_trap_result); /* Copy trap result keys into the enumerator object. */ len = (duk_uint_fast32_t) duk_get_length(ctx, -1); for (i = 0; i < len; i++) { /* XXX: not sure what the correct semantic details are here, * e.g. handling of missing values (gaps), handling of non-array * trap results, etc. * * For keys, we simply skip non-string keys which seems to be * consistent with how e.g. Object.keys() will process proxy trap * results (ES6 draft, Section 19.1.2.14). */ if (duk_get_prop_index(ctx, -1, i) && duk_is_string(ctx, -1)) { /* [ ... enum_target res trap_result val ] */ duk_push_true(ctx); /* [ ... enum_target res trap_result val true ] */ duk_put_prop(ctx, -4); } else { duk_pop(ctx); } } /* [ ... enum_target res trap_result ] */ duk_pop(ctx); duk_remove(ctx, -2); /* [ ... res ] */ /* The internal _target property is kept pointing to the original * enumeration target (the proxy object), so that the enumerator * 'next' operation can read property values if so requested. The * fact that the _target is a proxy disables key existence check * during enumeration. */ DUK_DDD(DUK_DDDPRINT("proxy enumeration, final res: %!O", (duk_heaphdr *) res)); goto compact_and_return; skip_proxy: #endif /* DUK_USE_ES6_PROXY */ curr = enum_target; while (curr) { /* * Virtual properties. * * String and buffer indices are virtual and always enumerable, * 'length' is virtual and non-enumerable. Array and arguments * object props have special behavior but are concrete. */ if (DUK_HOBJECT_HAS_EXOTIC_STRINGOBJ(curr) || DUK_HOBJECT_HAS_EXOTIC_BUFFEROBJ(curr)) { /* String and buffer enumeration behavior is identical now, * so use shared handler. */ if (DUK_HOBJECT_HAS_EXOTIC_STRINGOBJ(curr)) { duk_hstring *h_val; h_val = duk_hobject_get_internal_value_string(thr->heap, curr); DUK_ASSERT(h_val != NULL); /* string objects must not created without internal value */ len = (duk_uint_fast32_t) DUK_HSTRING_GET_CHARLEN(h_val); } else { duk_hbuffer *h_val; DUK_ASSERT(DUK_HOBJECT_HAS_EXOTIC_BUFFEROBJ(curr)); h_val = duk_hobject_get_internal_value_buffer(thr->heap, curr); DUK_ASSERT(h_val != NULL); /* buffer objects must not created without internal value */ len = (duk_uint_fast32_t) DUK_HBUFFER_GET_SIZE(h_val); } for (i = 0; i < len; i++) { duk_hstring *k; k = duk_heap_string_intern_u32_checked(thr, i); DUK_ASSERT(k); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [enum_target res key true] */ duk_put_prop(ctx, -3); /* [enum_target res] */ } /* 'length' property is not enumerable, but is included if * non-enumerable properties are requested. */ if (enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE) { duk_push_hstring_stridx(ctx, DUK_STRIDX_LENGTH); duk_push_true(ctx); duk_put_prop(ctx, -3); } } else if (DUK_HOBJECT_HAS_EXOTIC_DUKFUNC(curr)) { if (enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE) { duk_push_hstring_stridx(ctx, DUK_STRIDX_LENGTH); duk_push_true(ctx); duk_put_prop(ctx, -3); } } /* * Array part * * Note: ordering between array and entry part must match 'abandon array' * behavior in duk_hobject_props.c: key order after an array is abandoned * must be the same. */ for (i = 0; i < (duk_uint_fast32_t) curr->a_size; i++) { duk_hstring *k; duk_tval *tv; tv = DUK_HOBJECT_A_GET_VALUE_PTR(curr, i); if (DUK_TVAL_IS_UNDEFINED_UNUSED(tv)) { continue; } k = duk_heap_string_intern_u32_checked(thr, i); DUK_ASSERT(k); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [enum_target res key true] */ duk_put_prop(ctx, -3); /* [enum_target res] */ } /* * Entries part */ for (i = 0; i < (duk_uint_fast32_t) curr->e_next; i++) { duk_hstring *k; k = DUK_HOBJECT_E_GET_KEY(curr, i); if (!k) { continue; } if (!DUK_HOBJECT_E_SLOT_IS_ENUMERABLE(curr, i) && !(enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE)) { continue; } if (DUK_HSTRING_HAS_INTERNAL(k) && !(enum_flags & DUK_ENUM_INCLUDE_INTERNAL)) { continue; } if ((enum_flags & DUK_ENUM_ARRAY_INDICES_ONLY) && (DUK_HSTRING_GET_ARRIDX_SLOW(k) == DUK_HSTRING_NO_ARRAY_INDEX)) { continue; } DUK_ASSERT(DUK_HOBJECT_E_SLOT_IS_ACCESSOR(curr, i) || !DUK_TVAL_IS_UNDEFINED_UNUSED(&DUK_HOBJECT_E_GET_VALUE_PTR(curr, i)->v)); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [enum_target res key true] */ duk_put_prop(ctx, -3); /* [enum_target res] */ } if (enum_flags & DUK_ENUM_OWN_PROPERTIES_ONLY) { break; } curr = curr->prototype; } /* [enum_target res] */ duk_remove(ctx, -2); /* [res] */ if ((enum_flags & (DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) == (DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) { /* * Some E5/E5.1 algorithms require that array indices are iterated * in a strictly ascending order. This is the case for e.g. * Array.prototype.forEach() and JSON.stringify() PropertyList * handling. * * To ensure this property for arrays with an array part (and * arbitrary objects too, since e.g. forEach() can be applied * to an array), the caller can request that we sort the keys * here. */ /* XXX: avoid this at least when enum_target is an Array, it has an * array part, and no ancestor properties were included? Not worth * it for JSON, but maybe worth it for forEach(). */ /* XXX: may need a 'length' filter for forEach() */ DUK_DDD(DUK_DDDPRINT("sort array indices by caller request")); duk__sort_array_indices(res); } #if defined(DUK_USE_ES6_PROXY) compact_and_return: #endif /* compact; no need to seal because object is internal */ duk_hobject_compact_props(thr, res); DUK_DDD(DUK_DDDPRINT("created enumerator object: %!iT", (duk_tval *) duk_get_tval(ctx, -1))); }
void duk_hobject_enumerator_create(duk_context *ctx, int enum_flags) { duk_hthread *thr = (duk_hthread *) ctx; duk_hobject *target; duk_hobject *curr; duk_hobject *res; DUK_ASSERT(ctx != NULL); DUK_DDDPRINT("create enumerator, stack top: %d", duk_get_top(ctx)); target = duk_require_hobject(ctx, -1); DUK_ASSERT(target != NULL); duk_push_object_internal(ctx); DUK_DDDPRINT("created internal object"); /* [target res] */ duk_push_hstring_stridx(ctx, DUK_STRIDX_INT_TARGET); duk_push_hobject(ctx, target); duk_put_prop(ctx, -3); /* initialize index so that we skip internal control keys */ duk_push_hstring_stridx(ctx, DUK_STRIDX_INT_NEXT); duk_push_int(ctx, ENUM_START_INDEX); duk_put_prop(ctx, -3); curr = target; while (curr) { duk_uint32_t i; /* * Virtual properties. * * String indices are virtual and always enumerable. String 'length' * is virtual and non-enumerable. Array and arguments object props * have special behavior but are concrete. */ if (DUK_HOBJECT_HAS_SPECIAL_STRINGOBJ(curr)) { duk_hstring *h_val; h_val = duk_hobject_get_internal_value_string(thr->heap, curr); DUK_ASSERT(h_val != NULL); /* string objects must not created without internal value */ /* FIXME: type for 'i' to match string max len (duk_uint32_t) */ for (i = 0; i < DUK_HSTRING_GET_CHARLEN(h_val); i++) { duk_hstring *k; k = duk_heap_string_intern_u32_checked(thr, i); DUK_ASSERT(k); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [target res key true] */ duk_put_prop(ctx, -3); /* [target res] */ } /* 'length' property is not enumerable, but is included if * non-enumerable properties are requested. */ if (enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE) { duk_push_hstring_stridx(ctx, DUK_STRIDX_LENGTH); duk_push_true(ctx); duk_put_prop(ctx, -3); } } /* * Array part * * Note: ordering between array and entry part must match 'abandon array' * behavior in duk_hobject_props.c: key order after an array is abandoned * must be the same. */ for (i = 0; i < curr->a_size; i++) { duk_hstring *k; duk_tval *tv; tv = DUK_HOBJECT_A_GET_VALUE_PTR(curr, i); if (DUK_TVAL_IS_UNDEFINED_UNUSED(tv)) { continue; } k = duk_heap_string_intern_u32_checked(thr, i); DUK_ASSERT(k); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [target res key true] */ duk_put_prop(ctx, -3); /* [target res] */ } /* * Entries part */ for (i = 0; i < curr->e_used; i++) { duk_hstring *k; k = DUK_HOBJECT_E_GET_KEY(curr, i); if (!k) { continue; } if (!DUK_HOBJECT_E_SLOT_IS_ENUMERABLE(curr, i) && !(enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE)) { continue; } if (DUK_HSTRING_HAS_INTERNAL(k) && !(enum_flags & DUK_ENUM_INCLUDE_INTERNAL)) { continue; } if ((enum_flags & DUK_ENUM_ARRAY_INDICES_ONLY) && (DUK_HSTRING_GET_ARRIDX_SLOW(k) == DUK_HSTRING_NO_ARRAY_INDEX)) { continue; } DUK_ASSERT(DUK_HOBJECT_E_SLOT_IS_ACCESSOR(curr, i) || !DUK_TVAL_IS_UNDEFINED_UNUSED(&DUK_HOBJECT_E_GET_VALUE_PTR(curr, i)->v)); duk_push_hstring(ctx, k); duk_push_true(ctx); /* [target res key true] */ duk_put_prop(ctx, -3); /* [target res] */ } if (enum_flags & DUK_ENUM_OWN_PROPERTIES_ONLY) { break; } curr = curr->prototype; } /* [target res] */ duk_remove(ctx, -2); res = duk_require_hobject(ctx, -1); /* [res] */ if ((enum_flags & (DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) == (DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) { /* * Some E5/E5.1 algorithms require that array indices are iterated * in a strictly ascending order. This is the case for e.g. * Array.prototype.forEach() and JSON.stringify() PropertyList * handling. * * To ensure this property for arrays with an array part (and * arbitrary objects too, since e.g. forEach() can be applied * to an array), the caller can request that we sort the keys * here. */ /* FIXME: avoid this at least when target is an Array, it has an * array part, and no ancestor properties were included? Not worth * it for JSON, but maybe worth it for forEach(). */ /* FIXME: may need a 'length' filter for forEach() */ DUK_DDDPRINT("sort array indices by caller request"); sort_array_indices(res); } /* compact; no need to seal because object is internal */ duk_hobject_compact_props(thr, res); DUK_DDDPRINT("created enumerator object: %!iT", duk_get_tval(ctx, -1)); }