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/*
* Function built-ins
*/
#include "duk_internal.h"
DUK_INTERNAL duk_ret_t duk_bi_function_constructor(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hstring *h_sourcecode;
duk_idx_t nargs;
duk_idx_t i;
duk_small_uint_t comp_flags;
duk_hcompiledfunction *func;
duk_hobject *outer_lex_env;
duk_hobject *outer_var_env;
/* normal and constructor calls have identical semantics */
nargs = duk_get_top(ctx);
for (i = 0; i < nargs; i++) {
duk_to_string(ctx, i);
}
if (nargs == 0) {
duk_push_string(ctx, "");
duk_push_string(ctx, "");
} else if (nargs == 1) {
/* XXX: cover this with the generic >1 case? */
duk_push_string(ctx, "");
} else {
duk_insert(ctx, 0); /* [ arg1 ... argN-1 body] -> [body arg1 ... argN-1] */
duk_push_string(ctx, ",");
duk_insert(ctx, 1);
duk_join(ctx, nargs - 1);
}
/* [ body formals ], formals is comma separated list that needs to be parsed */
DUK_ASSERT_TOP(ctx, 2);
/* XXX: this placeholder is not always correct, but use for now.
* It will fail in corner cases; see test-dev-func-cons-args.js.
*/
duk_push_string(ctx, "function(");
duk_dup(ctx, 1);
duk_push_string(ctx, "){");
duk_dup(ctx, 0);
duk_push_string(ctx, "}");
duk_concat(ctx, 5);
/* [ body formals source ] */
DUK_ASSERT_TOP(ctx, 3);
/* strictness is not inherited, intentional */
comp_flags = DUK_JS_COMPILE_FLAG_FUNCEXPR;
duk_push_hstring_stridx(ctx, DUK_STRIDX_COMPILE); /* XXX: copy from caller? */ /* XXX: ignored now */
h_sourcecode = duk_require_hstring(ctx, -2);
duk_js_compile(thr,
(const duk_uint8_t *) DUK_HSTRING_GET_DATA(h_sourcecode),
(duk_size_t) DUK_HSTRING_GET_BYTELEN(h_sourcecode),
comp_flags);
func = (duk_hcompiledfunction *) duk_get_hobject(ctx, -1);
DUK_ASSERT(func != NULL);
DUK_ASSERT(DUK_HOBJECT_IS_COMPILEDFUNCTION((duk_hobject *) func));
/* [ body formals source template ] */
/* only outer_lex_env matters, as functions always get a new
* variable declaration environment.
*/
outer_lex_env = thr->builtins[DUK_BIDX_GLOBAL_ENV];
outer_var_env = thr->builtins[DUK_BIDX_GLOBAL_ENV];
duk_js_push_closure(thr, func, outer_var_env, outer_lex_env);
/* [ body formals source template closure ] */
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_function_prototype(duk_context *ctx) {
/* ignore arguments, return undefined (E5 Section 15.3.4) */
DUK_UNREF(ctx);
return 0;
}
DUK_INTERNAL duk_ret_t duk_bi_function_prototype_to_string(duk_context *ctx) {
duk_tval *tv;
/*
* E5 Section 15.3.4.2 places few requirements on the output of
* this function:
*
* - The result is an implementation dependent representation
* of the function; in particular
*
* - The result must follow the syntax of a FunctionDeclaration.
* In particular, the function must have a name (even in the
* case of an anonymous function or a function with an empty
* name).
*
* - Note in particular that the output does NOT need to compile
* into anything useful.
*/
/* XXX: faster internal way to get this */
duk_push_this(ctx);
tv = duk_get_tval(ctx, -1);
DUK_ASSERT(tv != NULL);
if (DUK_TVAL_IS_OBJECT(tv)) {
duk_hobject *obj = DUK_TVAL_GET_OBJECT(tv);
const char *func_name;
/* Function name: missing/undefined is mapped to empty string,
* otherwise coerce to string.
*/
/* XXX: currently no handling for non-allowed identifier characters,
* e.g. a '{' in the function name.
*/
duk_get_prop_stridx(ctx, -1, DUK_STRIDX_NAME);
if (duk_is_undefined(ctx, -1)) {
func_name = "";
} else {
func_name = duk_to_string(ctx, -1);
DUK_ASSERT(func_name != NULL);
}
/* Indicate function type in the function body using a dummy
* directive.
*/
if (DUK_HOBJECT_HAS_COMPILEDFUNCTION(obj)) {
duk_push_sprintf(ctx, "function %s() {\"ecmascript\"}", (const char *) func_name);
} else if (DUK_HOBJECT_HAS_NATIVEFUNCTION(obj)) {
duk_push_sprintf(ctx, "function %s() {\"native\"}", (const char *) func_name);
} else if (DUK_HOBJECT_HAS_BOUND(obj)) {
duk_push_sprintf(ctx, "function %s() {\"bound\"}", (const char *) func_name);
} else {
goto type_error;
}
} else if (DUK_TVAL_IS_LIGHTFUNC(tv)) {
duk_push_lightfunc_tostring(ctx, tv);
} else {
goto type_error;
}
return 1;
type_error:
return DUK_RET_TYPE_ERROR;
}
DUK_INTERNAL duk_ret_t duk_bi_function_prototype_apply(duk_context *ctx) {
duk_idx_t len;
duk_idx_t i;
DUK_ASSERT_TOP(ctx, 2); /* not a vararg function */
duk_push_this(ctx);
if (!duk_is_callable(ctx, -1)) {
DUK_DDD(DUK_DDDPRINT("func is not callable"));
goto type_error;
}
duk_insert(ctx, 0);
DUK_ASSERT_TOP(ctx, 3);
DUK_DDD(DUK_DDDPRINT("func=%!iT, thisArg=%!iT, argArray=%!iT",
(duk_tval *) duk_get_tval(ctx, 0),
(duk_tval *) duk_get_tval(ctx, 1),
(duk_tval *) duk_get_tval(ctx, 2)));
/* [ func thisArg argArray ] */
if (duk_is_null_or_undefined(ctx, 2)) {
DUK_DDD(DUK_DDDPRINT("argArray is null/undefined, no args"));
len = 0;
} else if (!duk_is_object(ctx, 2)) {
goto type_error;
} else {
DUK_DDD(DUK_DDDPRINT("argArray is an object"));
/* XXX: make this an internal helper */
duk_get_prop_stridx(ctx, 2, DUK_STRIDX_LENGTH);
len = (duk_idx_t) duk_to_uint32(ctx, -1); /* ToUint32() coercion required */
duk_pop(ctx);
duk_require_stack(ctx, len);
DUK_DDD(DUK_DDDPRINT("argArray length is %ld", (long) len));
for (i = 0; i < len; i++) {
duk_get_prop_index(ctx, 2, i);
}
}
duk_remove(ctx, 2);
DUK_ASSERT_TOP(ctx, 2 + len);
/* [ func thisArg arg1 ... argN ] */
DUK_DDD(DUK_DDDPRINT("apply, func=%!iT, thisArg=%!iT, len=%ld",
(duk_tval *) duk_get_tval(ctx, 0),
(duk_tval *) duk_get_tval(ctx, 1),
(long) len));
duk_call_method(ctx, len);
return 1;
type_error:
return DUK_RET_TYPE_ERROR;
}
DUK_INTERNAL duk_ret_t duk_bi_function_prototype_call(duk_context *ctx) {
duk_idx_t nargs;
/* Step 1 is not necessary because duk_call_method() will take
* care of it.
*/
/* vararg function, thisArg needs special handling */
nargs = duk_get_top(ctx); /* = 1 + arg count */
if (nargs == 0) {
duk_push_undefined(ctx);
nargs++;
}
DUK_ASSERT(nargs >= 1);
/* [ thisArg arg1 ... argN ] */
duk_push_this(ctx); /* 'func' in the algorithm */
duk_insert(ctx, 0);
/* [ func thisArg arg1 ... argN ] */
DUK_DDD(DUK_DDDPRINT("func=%!iT, thisArg=%!iT, argcount=%ld, top=%ld",
(duk_tval *) duk_get_tval(ctx, 0),
(duk_tval *) duk_get_tval(ctx, 1),
(long) (nargs - 1),
(long) duk_get_top(ctx)));
duk_call_method(ctx, nargs - 1);
return 1;
}
/* XXX: the implementation now assumes "chained" bound functions,
* whereas "collapsed" bound functions (where there is ever only
* one bound function which directly points to a non-bound, final
* function) would require a "collapsing" implementation which
* merges argument lists etc here.
*/
DUK_INTERNAL duk_ret_t duk_bi_function_prototype_bind(duk_context *ctx) {
duk_hobject *h_bound;
duk_hobject *h_target;
duk_idx_t nargs;
duk_idx_t i;
/* vararg function, careful arg handling (e.g. thisArg may not be present) */
nargs = duk_get_top(ctx); /* = 1 + arg count */
if (nargs == 0) {
duk_push_undefined(ctx);
nargs++;
}
DUK_ASSERT(nargs >= 1);
duk_push_this(ctx);
if (!duk_is_callable(ctx, -1)) {
DUK_DDD(DUK_DDDPRINT("func is not callable"));
goto type_error;
}
/* [ thisArg arg1 ... argN func ] (thisArg+args == nargs total) */
DUK_ASSERT_TOP(ctx, nargs + 1);
/* create bound function object */
duk_push_object_helper(ctx,
DUK_HOBJECT_FLAG_EXTENSIBLE |
DUK_HOBJECT_FLAG_BOUND |
DUK_HOBJECT_FLAG_CONSTRUCTABLE |
DUK_HOBJECT_CLASS_AS_FLAGS(DUK_HOBJECT_CLASS_FUNCTION),
DUK_BIDX_FUNCTION_PROTOTYPE);
h_bound = duk_get_hobject(ctx, -1);
DUK_ASSERT(h_bound != NULL);
/* [ thisArg arg1 ... argN func boundFunc ] */
duk_dup(ctx, -2); /* func */
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_TARGET, DUK_PROPDESC_FLAGS_NONE);
duk_dup(ctx, 0); /* thisArg */
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_THIS, DUK_PROPDESC_FLAGS_NONE);
duk_push_array(ctx);
/* [ thisArg arg1 ... argN func boundFunc argArray ] */
for (i = 0; i < nargs - 1; i++) {
duk_dup(ctx, 1 + i);
duk_put_prop_index(ctx, -2, i);
}
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_ARGS, DUK_PROPDESC_FLAGS_NONE);
/* [ thisArg arg1 ... argN func boundFunc ] */
/* bound function 'length' property is interesting */
h_target = duk_get_hobject(ctx, -2);
if (h_target == NULL || /* lightfunc */
DUK_HOBJECT_GET_CLASS_NUMBER(h_target) == DUK_HOBJECT_CLASS_FUNCTION) {
/* For lightfuncs, simply read the virtual property. */
duk_int_t tmp;
duk_get_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH);
tmp = duk_to_int(ctx, -1) - (nargs - 1); /* step 15.a */
duk_pop(ctx);
duk_push_int(ctx, (tmp < 0 ? 0 : tmp));
} else {
duk_push_int(ctx, 0);
}
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_NONE); /* attrs in E5 Section 15.3.5.1 */
/* caller and arguments must use the same thrower, [[ThrowTypeError]] */
duk_xdef_prop_stridx_thrower(ctx, -1, DUK_STRIDX_CALLER, DUK_PROPDESC_FLAGS_NONE);
duk_xdef_prop_stridx_thrower(ctx, -1, DUK_STRIDX_LC_ARGUMENTS, DUK_PROPDESC_FLAGS_NONE);
/* these non-standard properties are copied for convenience */
/* XXX: 'copy properties' API call? */
duk_get_prop_stridx(ctx, -2, DUK_STRIDX_NAME);
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_NAME, DUK_PROPDESC_FLAGS_WC);
duk_get_prop_stridx(ctx, -2, DUK_STRIDX_FILE_NAME);
duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_FILE_NAME, DUK_PROPDESC_FLAGS_WC);
/* The 'strict' flag is copied to get the special [[Get]] of E5.1
* Section 15.3.5.4 to apply when a 'caller' value is a strict bound
* function. Not sure if this is correct, because the specification
* is a bit ambiguous on this point but it would make sense.
*/
if (h_target == NULL) {
/* Lightfuncs are always strict. */
DUK_HOBJECT_SET_STRICT(h_bound);
} else if (DUK_HOBJECT_HAS_STRICT(h_target)) {
DUK_HOBJECT_SET_STRICT(h_bound);
}
DUK_DDD(DUK_DDDPRINT("created bound function: %!iT", (duk_tval *) duk_get_tval(ctx, -1)));
return 1;
type_error:
return DUK_RET_TYPE_ERROR;
}