/* Object.defineProperty() equivalent C binding. */ DUK_EXTERNAL void duk_def_prop(duk_context *ctx, duk_idx_t obj_index, duk_uint_t flags) { duk_hthread *thr = (duk_hthread *) ctx; duk_idx_t idx_base; duk_hobject *obj; duk_hstring *key; duk_idx_t idx_value; duk_hobject *get; duk_hobject *set; duk_uint_t is_data_desc; duk_uint_t is_acc_desc; DUK_ASSERT_CTX_VALID(ctx); obj = duk_require_hobject(ctx, obj_index); is_data_desc = flags & (DUK_DEFPROP_HAVE_VALUE | DUK_DEFPROP_HAVE_WRITABLE); is_acc_desc = flags & (DUK_DEFPROP_HAVE_GETTER | DUK_DEFPROP_HAVE_SETTER); if (is_data_desc && is_acc_desc) { /* "Have" flags must not be conflicting so that they would * apply to both a plain property and an accessor at the same * time. */ goto fail_invalid_desc; } idx_base = duk_get_top_index(ctx); if (flags & DUK_DEFPROP_HAVE_SETTER) { duk_require_type_mask(ctx, idx_base, DUK_TYPE_MASK_UNDEFINED | DUK_TYPE_MASK_OBJECT | DUK_TYPE_MASK_LIGHTFUNC); set = duk_get_hobject_or_lfunc_coerce(ctx, idx_base); if (set != NULL && !DUK_HOBJECT_IS_CALLABLE(set)) { goto fail_not_callable; } idx_base--; } else { set = NULL; } if (flags & DUK_DEFPROP_HAVE_GETTER) { duk_require_type_mask(ctx, idx_base, DUK_TYPE_MASK_UNDEFINED | DUK_TYPE_MASK_OBJECT | DUK_TYPE_MASK_LIGHTFUNC); get = duk_get_hobject_or_lfunc_coerce(ctx, idx_base); if (get != NULL && !DUK_HOBJECT_IS_CALLABLE(get)) { goto fail_not_callable; } idx_base--; } else { get = NULL; } if (flags & DUK_DEFPROP_HAVE_VALUE) { idx_value = idx_base; idx_base--; } else { idx_value = (duk_idx_t) -1; } key = duk_require_hstring(ctx, idx_base); duk_require_valid_index(ctx, idx_base); duk_hobject_define_property_helper(ctx, flags /*defprop_flags*/, obj, key, idx_value, get, set); /* Clean up stack */ duk_set_top(ctx, idx_base); /* [ ... obj ... ] */ return; fail_invalid_desc: DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, DUK_STR_INVALID_DESCRIPTOR); return; fail_not_callable: DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, DUK_STR_NOT_CALLABLE); return; }
DUK_INTERNAL duk_bool_t duk_js_instanceof(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y) { duk_context *ctx = (duk_context *) thr; duk_hobject *func; duk_hobject *val; duk_hobject *proto; duk_uint_t sanity; /* * Get the values onto the stack first. It would be possible to cover * some normal cases without resorting to the value stack. * * The right hand side could be a light function (as they generally * behave like objects). Light functions never have a 'prototype' * property so E5.1 Section 15.3.5.3 step 3 always throws a TypeError. * Using duk_require_hobject() is thus correct (except for error msg). */ duk_push_tval(ctx, tv_x); duk_push_tval(ctx, tv_y); func = duk_require_hobject(ctx, -1); /* * For bound objects, [[HasInstance]] just calls the target function * [[HasInstance]]. If that is again a bound object, repeat until * we find a non-bound Function object. */ /* XXX: this bound function resolution also happens elsewhere, * move into a shared helper. */ sanity = DUK_HOBJECT_BOUND_CHAIN_SANITY; do { /* check func supports [[HasInstance]] (this is checked for every function * in the bound chain, including the final one) */ if (!DUK_HOBJECT_IS_CALLABLE(func)) { /* * Note: of native Ecmascript objects, only Function instances * have a [[HasInstance]] internal property. Custom objects might * also have it, but not in current implementation. * * XXX: add a separate flag, DUK_HOBJECT_FLAG_ALLOW_INSTANCEOF? */ DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, "invalid instanceof rval"); } if (!DUK_HOBJECT_HAS_BOUND(func)) { break; } /* [ ... lval rval ] */ duk_get_prop_stridx(ctx, -1, DUK_STRIDX_INT_TARGET); /* -> [ ... lval rval new_rval ] */ duk_replace(ctx, -1); /* -> [ ... lval new_rval ] */ func = duk_require_hobject(ctx, -1); /* func support for [[HasInstance]] checked in the beginning of the loop */ } while (--sanity > 0); if (sanity == 0) { DUK_ERROR(thr, DUK_ERR_INTERNAL_ERROR, DUK_STR_BOUND_CHAIN_LIMIT); } /* * 'func' is now a non-bound object which supports [[HasInstance]] * (which here just means DUK_HOBJECT_FLAG_CALLABLE). Move on * to execute E5 Section 15.3.5.3. */ DUK_ASSERT(!DUK_HOBJECT_HAS_BOUND(func)); DUK_ASSERT(DUK_HOBJECT_IS_CALLABLE(func)); /* [ ... lval rval(func) ] */ /* Handle lightfuncs through object coercion for now. */ /* XXX: direct implementation */ val = duk_get_hobject_or_lfunc_coerce(ctx, -2); if (!val) { goto pop_and_false; } duk_get_prop_stridx(ctx, -1, DUK_STRIDX_PROTOTYPE); /* -> [ ... lval rval rval.prototype ] */ proto = duk_require_hobject(ctx, -1); duk_pop(ctx); /* -> [ ... lval rval ] */ sanity = DUK_HOBJECT_PROTOTYPE_CHAIN_SANITY; do { /* * Note: prototype chain is followed BEFORE first comparison. This * means that the instanceof lval is never itself compared to the * rval.prototype property. This is apparently intentional, see E5 * Section 15.3.5.3, step 4.a. * * Also note: * * js> (function() {}) instanceof Function * true * js> Function instanceof Function * true * * For the latter, h_proto will be Function.prototype, which is the * built-in Function prototype. Because Function.[[Prototype]] is * also the built-in Function prototype, the result is true. */ val = DUK_HOBJECT_GET_PROTOTYPE(thr->heap, val); if (!val) { goto pop_and_false; } else if (val == proto) { goto pop_and_true; } /* follow prototype chain */ } while (--sanity > 0); if (sanity == 0) { DUK_ERROR(thr, DUK_ERR_INTERNAL_ERROR, DUK_STR_PROTOTYPE_CHAIN_LIMIT); } DUK_UNREACHABLE(); pop_and_false: duk_pop_2(ctx); return 0; pop_and_true: duk_pop_2(ctx); return 1; }