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diff --git a/src/civetweb/src/third_party/duktape-1.5.2/src-separate/duk_bi_array.c b/src/civetweb/src/third_party/duktape-1.5.2/src-separate/duk_bi_array.c
new file mode 100644
index 000000000..dfb93dfdb
--- /dev/null
+++ b/src/civetweb/src/third_party/duktape-1.5.2/src-separate/duk_bi_array.c
@@ -0,0 +1,1445 @@
+/*
+ * Array built-ins
+ *
+ * Note that most Array built-ins are intentionally generic and work even
+ * when the 'this' binding is not an Array instance. To ensure this,
+ * Array algorithms do not assume "magical" Array behavior for the "length"
+ * property, for instance.
+ *
+ * XXX: the "Throw" flag should be set for (almost?) all [[Put]] and
+ * [[Delete]] operations, but it's currently false throughout. Go through
+ * all put/delete cases and check throw flag use. Need a new API primitive
+ * which allows throws flag to be specified.
+ *
+ * XXX: array lengths above 2G won't work reliably. There are many places
+ * where one needs a full signed 32-bit range ([-0xffffffff, 0xffffffff],
+ * i.e. -33- bits). Although array 'length' cannot be written to be outside
+ * the unsigned 32-bit range (E5.1 Section 15.4.5.1 throws a RangeError if so)
+ * some intermediate values may be above 0xffffffff and this may not be always
+ * correctly handled now (duk_uint32_t is not enough for all algorithms).
+ *
+ * For instance, push() can legitimately write entries beyond length 0xffffffff
+ * and cause a RangeError only at the end. To do this properly, the current
+ * push() implementation tracks the array index using a 'double' instead of a
+ * duk_uint32_t (which is somewhat awkward). See test-bi-array-push-maxlen.js.
+ *
+ * On using "put" vs. "def" prop
+ * =============================
+ *
+ * Code below must be careful to use the appropriate primitive as it matters
+ * for compliance. When using "put" there may be inherited properties in
+ * Array.prototype which cause side effects when values are written. When
+ * using "define" there are no such side effects, and many test262 test cases
+ * check for this (for real world code, such side effects are very rare).
+ * Both "put" and "define" are used in the E5.1 specification; as a rule,
+ * "put" is used when modifying an existing array (or a non-array 'this'
+ * binding) and "define" for setting values into a fresh result array.
+ *
+ * Also note that Array instance 'length' should be writable, but not
+ * enumerable and definitely not configurable: even Duktape code internally
+ * assumes that an Array instance will always have a 'length' property.
+ * Preventing deletion of the property is critical.
+ */
+
+#include "duk_internal.h"
+
+/* Perform an intermediate join when this many elements have been pushed
+ * on the value stack.
+ */
+#define DUK__ARRAY_MID_JOIN_LIMIT 4096
+
+/* Shared entry code for many Array built-ins. Note that length is left
+ * on stack (it could be popped, but that's not necessary).
+ */
+DUK_LOCAL duk_uint32_t duk__push_this_obj_len_u32(duk_context *ctx) {
+ duk_uint32_t len;
+
+ (void) duk_push_this_coercible_to_object(ctx);
+ duk_get_prop_stridx(ctx, -1, DUK_STRIDX_LENGTH);
+ len = duk_to_uint32(ctx, -1);
+
+ /* -> [ ... ToObject(this) ToUint32(length) ] */
+ return len;
+}
+
+DUK_LOCAL duk_uint32_t duk__push_this_obj_len_u32_limited(duk_context *ctx) {
+ /* Range limited to [0, 0x7fffffff] range, i.e. range that can be
+ * represented with duk_int32_t. Use this when the method doesn't
+ * handle the full 32-bit unsigned range correctly.
+ */
+ duk_uint32_t ret = duk__push_this_obj_len_u32(ctx);
+ if (DUK_UNLIKELY(ret >= 0x80000000UL)) {
+ DUK_ERROR_RANGE((duk_hthread *) ctx, DUK_STR_ARRAY_LENGTH_OVER_2G);
+ }
+ return ret;
+}
+
+/*
+ * Constructor
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_constructor(duk_context *ctx) {
+ duk_idx_t nargs;
+ duk_double_t d;
+ duk_uint32_t len;
+ duk_idx_t i;
+
+ nargs = duk_get_top(ctx);
+ duk_push_array(ctx);
+
+ if (nargs == 1 && duk_is_number(ctx, 0)) {
+ /* XXX: expensive check (also shared elsewhere - so add a shared internal API call?) */
+ d = duk_get_number(ctx, 0);
+ len = duk_to_uint32(ctx, 0);
+ if (((duk_double_t) len) != d) {
+ return DUK_RET_RANGE_ERROR;
+ }
+
+ /* XXX: if 'len' is low, may want to ensure array part is kept:
+ * the caller is likely to want a dense array.
+ */
+ duk_push_u32(ctx, len);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W); /* [ ToUint32(len) array ToUint32(len) ] -> [ ToUint32(len) array ] */
+ return 1;
+ }
+
+ /* XXX: optimize by creating array into correct size directly, and
+ * operating on the array part directly; values can be memcpy()'d from
+ * value stack directly as long as refcounts are increased.
+ */
+ for (i = 0; i < nargs; i++) {
+ duk_dup(ctx, i);
+ duk_xdef_prop_index_wec(ctx, -2, (duk_uarridx_t) i);
+ }
+
+ duk_push_u32(ctx, (duk_uint32_t) nargs);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
+ return 1;
+}
+
+/*
+ * isArray()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_constructor_is_array(duk_context *ctx) {
+ duk_hobject *h;
+
+ h = duk_get_hobject_with_class(ctx, 0, DUK_HOBJECT_CLASS_ARRAY);
+ duk_push_boolean(ctx, (h != NULL));
+ return 1;
+}
+
+/*
+ * toString()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_to_string(duk_context *ctx) {
+ (void) duk_push_this_coercible_to_object(ctx);
+ duk_get_prop_stridx(ctx, -1, DUK_STRIDX_JOIN);
+
+ /* [ ... this func ] */
+ if (!duk_is_callable(ctx, -1)) {
+ /* Fall back to the initial (original) Object.toString(). We don't
+ * currently have pointers to the built-in functions, only the top
+ * level global objects (like "Array") so this is now done in a bit
+ * of a hacky manner. It would be cleaner to push the (original)
+ * function and use duk_call_method().
+ */
+
+ /* XXX: 'this' will be ToObject() coerced twice, which is incorrect
+ * but should have no visible side effects.
+ */
+ DUK_DDD(DUK_DDDPRINT("this.join is not callable, fall back to (original) Object.toString"));
+ duk_set_top(ctx, 0);
+ return duk_bi_object_prototype_to_string(ctx); /* has access to 'this' binding */
+ }
+
+ /* [ ... this func ] */
+
+ duk_insert(ctx, -2);
+
+ /* [ ... func this ] */
+
+ DUK_DDD(DUK_DDDPRINT("calling: func=%!iT, this=%!iT",
+ (duk_tval *) duk_get_tval(ctx, -2),
+ (duk_tval *) duk_get_tval(ctx, -1)));
+ duk_call_method(ctx, 0);
+
+ return 1;
+}
+
+/*
+ * concat()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_concat(duk_context *ctx) {
+ duk_idx_t i, n;
+ duk_uarridx_t idx, idx_last;
+ duk_uarridx_t j, len;
+ duk_hobject *h;
+
+ /* XXX: the insert here is a bit expensive if there are a lot of items.
+ * It could also be special cased in the outermost for loop quite easily
+ * (as the element is dup()'d anyway).
+ */
+
+ (void) duk_push_this_coercible_to_object(ctx);
+ duk_insert(ctx, 0);
+ n = duk_get_top(ctx);
+ duk_push_array(ctx); /* -> [ ToObject(this) item1 ... itemN arr ] */
+
+ /* NOTE: The Array special behaviors are NOT invoked by duk_xdef_prop_index()
+ * (which differs from the official algorithm). If no error is thrown, this
+ * doesn't matter as the length is updated at the end. However, if an error
+ * is thrown, the length will be unset. That shouldn't matter because the
+ * caller won't get a reference to the intermediate value.
+ */
+
+ idx = 0;
+ idx_last = 0;
+ for (i = 0; i < n; i++) {
+ DUK_ASSERT_TOP(ctx, n + 1);
+
+ /* [ ToObject(this) item1 ... itemN arr ] */
+
+ duk_dup(ctx, i);
+ h = duk_get_hobject_with_class(ctx, -1, DUK_HOBJECT_CLASS_ARRAY);
+ if (!h) {
+ duk_xdef_prop_index_wec(ctx, -2, idx++);
+ idx_last = idx;
+ continue;
+ }
+
+ /* [ ToObject(this) item1 ... itemN arr item(i) ] */
+
+ /* XXX: an array can have length higher than 32 bits; this is not handled
+ * correctly now.
+ */
+ len = (duk_uarridx_t) duk_get_length(ctx, -1);
+ for (j = 0; j < len; j++) {
+ if (duk_get_prop_index(ctx, -1, j)) {
+ /* [ ToObject(this) item1 ... itemN arr item(i) item(i)[j] ] */
+ duk_xdef_prop_index_wec(ctx, -3, idx++);
+ idx_last = idx;
+ } else {
+ idx++;
+ duk_pop(ctx);
+#if defined(DUK_USE_NONSTD_ARRAY_CONCAT_TRAILER)
+ /* According to E5.1 Section 15.4.4.4 nonexistent trailing
+ * elements do not affect 'length' of the result. Test262
+ * and other engines disagree, so update idx_last here too.
+ */
+ idx_last = idx;
+#else
+ /* Strict standard behavior, ignore trailing elements for
+ * result 'length'.
+ */
+#endif
+ }
+ }
+ duk_pop(ctx);
+ }
+
+ /* The E5.1 Section 15.4.4.4 algorithm doesn't set the length explicitly
+ * in the end, but because we're operating with an internal value which
+ * is known to be an array, this should be equivalent.
+ */
+ duk_push_uarridx(ctx, idx_last);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
+
+ DUK_ASSERT_TOP(ctx, n + 1);
+ return 1;
+}
+
+/*
+ * join(), toLocaleString()
+ *
+ * Note: checking valstack is necessary, but only in the per-element loop.
+ *
+ * Note: the trivial approach of pushing all the elements on the value stack
+ * and then calling duk_join() fails when the array contains a large number
+ * of elements. This problem can't be offloaded to duk_join() because the
+ * elements to join must be handled here and have special handling. Current
+ * approach is to do intermediate joins with very large number of elements.
+ * There is no fancy handling; the prefix gets re-joined multiple times.
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_join_shared(duk_context *ctx) {
+ duk_uint32_t len, count;
+ duk_uint32_t idx;
+ duk_small_int_t to_locale_string = duk_get_current_magic(ctx);
+ duk_idx_t valstack_required;
+
+ /* For join(), nargs is 1. For toLocaleString(), nargs is 0 and
+ * setting the top essentially pushes an undefined to the stack,
+ * thus defaulting to a comma separator.
+ */
+ duk_set_top(ctx, 1);
+ if (duk_is_undefined(ctx, 0)) {
+ duk_pop(ctx);
+ duk_push_hstring_stridx(ctx, DUK_STRIDX_COMMA);
+ } else {
+ duk_to_string(ctx, 0);
+ }
+
+ len = duk__push_this_obj_len_u32(ctx);
+
+ /* [ sep ToObject(this) len ] */
+
+ DUK_DDD(DUK_DDDPRINT("sep=%!T, this=%!T, len=%lu",
+ (duk_tval *) duk_get_tval(ctx, 0),
+ (duk_tval *) duk_get_tval(ctx, 1),
+ (unsigned long) len));
+
+ /* The extra (+4) is tight. */
+ valstack_required = (len >= DUK__ARRAY_MID_JOIN_LIMIT ?
+ DUK__ARRAY_MID_JOIN_LIMIT : len) + 4;
+ duk_require_stack(ctx, valstack_required);
+
+ duk_dup(ctx, 0);
+
+ /* [ sep ToObject(this) len sep ] */
+
+ count = 0;
+ idx = 0;
+ for (;;) {
+ if (count >= DUK__ARRAY_MID_JOIN_LIMIT || /* intermediate join to avoid valstack overflow */
+ idx >= len) { /* end of loop (careful with len==0) */
+ /* [ sep ToObject(this) len sep str0 ... str(count-1) ] */
+ DUK_DDD(DUK_DDDPRINT("mid/final join, count=%ld, idx=%ld, len=%ld",
+ (long) count, (long) idx, (long) len));
+ duk_join(ctx, (duk_idx_t) count); /* -> [ sep ToObject(this) len str ] */
+ duk_dup(ctx, 0); /* -> [ sep ToObject(this) len str sep ] */
+ duk_insert(ctx, -2); /* -> [ sep ToObject(this) len sep str ] */
+ count = 1;
+ }
+ if (idx >= len) {
+ /* if true, the stack already contains the final result */
+ break;
+ }
+
+ duk_get_prop_index(ctx, 1, (duk_uarridx_t) idx);
+ if (duk_is_null_or_undefined(ctx, -1)) {
+ duk_pop(ctx);
+ duk_push_hstring_stridx(ctx, DUK_STRIDX_EMPTY_STRING);
+ } else {
+ if (to_locale_string) {
+ duk_to_object(ctx, -1);
+ duk_get_prop_stridx(ctx, -1, DUK_STRIDX_TO_LOCALE_STRING);
+ duk_insert(ctx, -2); /* -> [ ... toLocaleString ToObject(val) ] */
+ duk_call_method(ctx, 0);
+ duk_to_string(ctx, -1);
+ } else {
+ duk_to_string(ctx, -1);
+ }
+ }
+
+ count++;
+ idx++;
+ }
+
+ /* [ sep ToObject(this) len sep result ] */
+
+ return 1;
+}
+
+/*
+ * pop(), push()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_pop(duk_context *ctx) {
+ duk_uint32_t len;
+ duk_uint32_t idx;
+
+ DUK_ASSERT_TOP(ctx, 0);
+ len = duk__push_this_obj_len_u32(ctx);
+ if (len == 0) {
+ duk_push_int(ctx, 0);
+ duk_put_prop_stridx(ctx, 0, DUK_STRIDX_LENGTH);
+ return 0;
+ }
+ idx = len - 1;
+
+ duk_get_prop_index(ctx, 0, (duk_uarridx_t) idx);
+ duk_del_prop_index(ctx, 0, (duk_uarridx_t) idx);
+ duk_push_u32(ctx, idx);
+ duk_put_prop_stridx(ctx, 0, DUK_STRIDX_LENGTH);
+ return 1;
+}
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_push(duk_context *ctx) {
+ /* Note: 'this' is not necessarily an Array object. The push()
+ * algorithm is supposed to work for other kinds of objects too,
+ * so the algorithm has e.g. an explicit update for the 'length'
+ * property which is normally "magical" in arrays.
+ */
+
+ duk_uint32_t len;
+ duk_idx_t i, n;
+
+ n = duk_get_top(ctx);
+ len = duk__push_this_obj_len_u32(ctx);
+
+ /* [ arg1 ... argN obj length ] */
+
+ /* Technically Array.prototype.push() can create an Array with length
+ * longer than 2^32-1, i.e. outside the 32-bit range. The final length
+ * is *not* wrapped to 32 bits in the specification.
+ *
+ * This implementation tracks length with a uint32 because it's much
+ * more practical.
+ *
+ * See: test-bi-array-push-maxlen.js.
+ */
+
+ if (len + (duk_uint32_t) n < len) {
+ DUK_D(DUK_DPRINT("Array.prototype.push() would go beyond 32-bit length, throw"));
+ return DUK_RET_RANGE_ERROR;
+ }
+
+ for (i = 0; i < n; i++) {
+ duk_dup(ctx, i);
+ duk_put_prop_index(ctx, -3, len + i);
+ }
+ len += n;
+
+ duk_push_u32(ctx, len);
+ duk_dup_top(ctx);
+ duk_put_prop_stridx(ctx, -4, DUK_STRIDX_LENGTH);
+
+ /* [ arg1 ... argN obj length new_length ] */
+ return 1;
+}
+
+/*
+ * sort()
+ *
+ * Currently qsort with random pivot. This is now really, really slow,
+ * because there is no fast path for array parts.
+ *
+ * Signed indices are used because qsort() leaves and degenerate cases
+ * may use a negative offset.
+ */
+
+DUK_LOCAL duk_small_int_t duk__array_sort_compare(duk_context *ctx, duk_int_t idx1, duk_int_t idx2) {
+ duk_bool_t have1, have2;
+ duk_bool_t undef1, undef2;
+ duk_small_int_t ret;
+ duk_idx_t idx_obj = 1; /* fixed offsets in valstack */
+ duk_idx_t idx_fn = 0;
+ duk_hstring *h1, *h2;
+
+ /* Fast exit if indices are identical. This is valid for a non-existent property,
+ * for an undefined value, and almost always for ToString() coerced comparison of
+ * arbitrary values (corner cases where this is not the case include e.g. a an
+ * object with varying ToString() coercion).
+ *
+ * The specification does not prohibit "caching" of values read from the array, so
+ * assuming equality for comparing an index with itself falls into the category of
+ * "caching".
+ *
+ * Also, compareFn may be inconsistent, so skipping a call to compareFn here may
+ * have an effect on the final result. The specification does not require any
+ * specific behavior for inconsistent compare functions, so again, this fast path
+ * is OK.
+ */
+
+ if (idx1 == idx2) {
+ DUK_DDD(DUK_DDDPRINT("duk__array_sort_compare: idx1=%ld, idx2=%ld -> indices identical, quick exit",
+ (long) idx1, (long) idx2));
+ return 0;
+ }
+
+ have1 = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) idx1);
+ have2 = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) idx2);
+
+ DUK_DDD(DUK_DDDPRINT("duk__array_sort_compare: idx1=%ld, idx2=%ld, have1=%ld, have2=%ld, val1=%!T, val2=%!T",
+ (long) idx1, (long) idx2, (long) have1, (long) have2,
+ (duk_tval *) duk_get_tval(ctx, -2), (duk_tval *) duk_get_tval(ctx, -1)));
+
+ if (have1) {
+ if (have2) {
+ ;
+ } else {
+ ret = -1;
+ goto pop_ret;
+ }
+ } else {
+ if (have2) {
+ ret = 1;
+ goto pop_ret;
+ } else {
+ ret = 0;
+ goto pop_ret;
+ }
+ }
+
+ undef1 = duk_is_undefined(ctx, -2);
+ undef2 = duk_is_undefined(ctx, -1);
+ if (undef1) {
+ if (undef2) {
+ ret = 0;
+ goto pop_ret;
+ } else {
+ ret = 1;
+ goto pop_ret;
+ }
+ } else {
+ if (undef2) {
+ ret = -1;
+ goto pop_ret;
+ } else {
+ ;
+ }
+ }
+
+ if (!duk_is_undefined(ctx, idx_fn)) {
+ duk_double_t d;
+
+ /* no need to check callable; duk_call() will do that */
+ duk_dup(ctx, idx_fn); /* -> [ ... x y fn ] */
+ duk_insert(ctx, -3); /* -> [ ... fn x y ] */
+ duk_call(ctx, 2); /* -> [ ... res ] */
+
+ /* The specification is a bit vague what to do if the return
+ * value is not a number. Other implementations seem to
+ * tolerate non-numbers but e.g. V8 won't apparently do a
+ * ToNumber().
+ */
+
+ /* XXX: best behavior for real world compatibility? */
+
+ d = duk_to_number(ctx, -1);
+ if (d < 0.0) {
+ ret = -1;
+ } else if (d > 0.0) {
+ ret = 1;
+ } else {
+ ret = 0;
+ }
+
+ duk_pop(ctx);
+ DUK_DDD(DUK_DDDPRINT("-> result %ld (from comparefn, after coercion)", (long) ret));
+ return ret;
+ }
+
+ /* string compare is the default (a bit oddly) */
+
+ h1 = duk_to_hstring(ctx, -2);
+ h2 = duk_to_hstring(ctx, -1);
+ DUK_ASSERT(h1 != NULL);
+ DUK_ASSERT(h2 != NULL);
+
+ ret = duk_js_string_compare(h1, h2); /* retval is directly usable */
+ goto pop_ret;
+
+ pop_ret:
+ duk_pop_2(ctx);
+ DUK_DDD(DUK_DDDPRINT("-> result %ld", (long) ret));
+ return ret;
+}
+
+DUK_LOCAL void duk__array_sort_swap(duk_context *ctx, duk_int_t l, duk_int_t r) {
+ duk_bool_t have_l, have_r;
+ duk_idx_t idx_obj = 1; /* fixed offset in valstack */
+
+ if (l == r) {
+ return;
+ }
+
+ /* swap elements; deal with non-existent elements correctly */
+ have_l = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) l);
+ have_r = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) r);
+
+ if (have_r) {
+ /* right exists, [[Put]] regardless whether or not left exists */
+ duk_put_prop_index(ctx, idx_obj, (duk_uarridx_t) l);
+ } else {
+ duk_del_prop_index(ctx, idx_obj, (duk_uarridx_t) l);
+ duk_pop(ctx);
+ }
+
+ if (have_l) {
+ duk_put_prop_index(ctx, idx_obj, (duk_uarridx_t) r);
+ } else {
+ duk_del_prop_index(ctx, idx_obj, (duk_uarridx_t) r);
+ duk_pop(ctx);
+ }
+}
+
+#if defined(DUK_USE_DDDPRINT)
+/* Debug print which visualizes the qsort partitioning process. */
+DUK_LOCAL void duk__debuglog_qsort_state(duk_context *ctx, duk_int_t lo, duk_int_t hi, duk_int_t pivot) {
+ char buf[4096];
+ char *ptr = buf;
+ duk_int_t i, n;
+ n = (duk_int_t) duk_get_length(ctx, 1);
+ if (n > 4000) {
+ n = 4000;
+ }
+ *ptr++ = '[';
+ for (i = 0; i < n; i++) {
+ if (i == pivot) {
+ *ptr++ = '|';
+ } else if (i == lo) {
+ *ptr++ = '<';
+ } else if (i == hi) {
+ *ptr++ = '>';
+ } else if (i >= lo && i <= hi) {
+ *ptr++ = '-';
+ } else {
+ *ptr++ = ' ';
+ }
+ }
+ *ptr++ = ']';
+ *ptr++ = '\0';
+
+ DUK_DDD(DUK_DDDPRINT("%s (lo=%ld, hi=%ld, pivot=%ld)",
+ (const char *) buf, (long) lo, (long) hi, (long) pivot));
+}
+#endif
+
+DUK_LOCAL void duk__array_qsort(duk_context *ctx, duk_int_t lo, duk_int_t hi) {
+ duk_hthread *thr = (duk_hthread *) ctx;
+ duk_int_t p, l, r;
+
+ /* The lo/hi indices may be crossed and hi < 0 is possible at entry. */
+
+ DUK_DDD(DUK_DDDPRINT("duk__array_qsort: lo=%ld, hi=%ld, obj=%!T",
+ (long) lo, (long) hi, (duk_tval *) duk_get_tval(ctx, 1)));
+
+ DUK_ASSERT_TOP(ctx, 3);
+
+ /* In some cases it may be that lo > hi, or hi < 0; these
+ * degenerate cases happen e.g. for empty arrays, and in
+ * recursion leaves.
+ */
+
+ /* trivial cases */
+ if (hi - lo < 1) {
+ DUK_DDD(DUK_DDDPRINT("degenerate case, return immediately"));
+ return;
+ }
+ DUK_ASSERT(hi > lo);
+ DUK_ASSERT(hi - lo + 1 >= 2);
+
+ /* randomized pivot selection */
+ p = lo + (duk_util_tinyrandom_get_bits(thr, 30) % (hi - lo + 1)); /* rnd in [lo,hi] */
+ DUK_ASSERT(p >= lo && p <= hi);
+ DUK_DDD(DUK_DDDPRINT("lo=%ld, hi=%ld, chose pivot p=%ld",
+ (long) lo, (long) hi, (long) p));
+
+ /* move pivot out of the way */
+ duk__array_sort_swap(ctx, p, lo);
+ p = lo;
+ DUK_DDD(DUK_DDDPRINT("pivot moved out of the way: %!T", (duk_tval *) duk_get_tval(ctx, 1)));
+
+ l = lo + 1;
+ r = hi;
+ for (;;) {
+ /* find elements to swap */
+ for (;;) {
+ DUK_DDD(DUK_DDDPRINT("left scan: l=%ld, r=%ld, p=%ld",
+ (long) l, (long) r, (long) p));
+ if (l >= hi) {
+ break;
+ }
+ if (duk__array_sort_compare(ctx, l, p) >= 0) { /* !(l < p) */
+ break;
+ }
+ l++;
+ }
+ for (;;) {
+ DUK_DDD(DUK_DDDPRINT("right scan: l=%ld, r=%ld, p=%ld",
+ (long) l, (long) r, (long) p));
+ if (r <= lo) {
+ break;
+ }
+ if (duk__array_sort_compare(ctx, p, r) >= 0) { /* !(p < r) */
+ break;
+ }
+ r--;
+ }
+ if (l >= r) {
+ goto done;
+ }
+ DUK_ASSERT(l < r);
+
+ DUK_DDD(DUK_DDDPRINT("swap %ld and %ld", (long) l, (long) r));
+
+ duk__array_sort_swap(ctx, l, r);
+
+ DUK_DDD(DUK_DDDPRINT("after swap: %!T", (duk_tval *) duk_get_tval(ctx, 1)));
+ l++;
+ r--;
+ }
+ done:
+ /* Note that 'l' and 'r' may cross, i.e. r < l */
+ DUK_ASSERT(l >= lo && l <= hi);
+ DUK_ASSERT(r >= lo && r <= hi);
+
+ /* XXX: there's no explicit recursion bound here now. For the average
+ * qsort recursion depth O(log n) that's not really necessary: e.g. for
+ * 2**32 recursion depth would be about 32 which is OK. However, qsort
+ * worst case recursion depth is O(n) which may be a problem.
+ */
+
+ /* move pivot to its final place */
+ DUK_DDD(DUK_DDDPRINT("before final pivot swap: %!T", (duk_tval *) duk_get_tval(ctx, 1)));
+ duk__array_sort_swap(ctx, lo, r);
+
+#if defined(DUK_USE_DDDPRINT)
+ duk__debuglog_qsort_state(ctx, lo, hi, r);
+#endif
+
+ DUK_DDD(DUK_DDDPRINT("recurse: pivot=%ld, obj=%!T", (long) r, (duk_tval *) duk_get_tval(ctx, 1)));
+ duk__array_qsort(ctx, lo, r - 1);
+ duk__array_qsort(ctx, r + 1, hi);
+}
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_sort(duk_context *ctx) {
+ duk_uint32_t len;
+
+ /* XXX: len >= 0x80000000 won't work below because a signed type
+ * is needed by qsort.
+ */
+ len = duk__push_this_obj_len_u32_limited(ctx);
+
+ /* stack[0] = compareFn
+ * stack[1] = ToObject(this)
+ * stack[2] = ToUint32(length)
+ */
+
+ if (len > 0) {
+ /* avoid degenerate cases, so that (len - 1) won't underflow */
+ duk__array_qsort(ctx, (duk_int_t) 0, (duk_int_t) (len - 1));
+ }
+
+ DUK_ASSERT_TOP(ctx, 3);
+ duk_pop(ctx);
+ return 1; /* return ToObject(this) */
+}
+
+/*
+ * splice()
+ */
+
+/* XXX: this compiles to over 500 bytes now, even without special handling
+ * for an array part. Uses signed ints so does not handle full array range correctly.
+ */
+
+/* XXX: can shift() / unshift() use the same helper?
+ * shift() is (close to?) <--> splice(0, 1)
+ * unshift is (close to?) <--> splice(0, 0, [items])?
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_splice(duk_context *ctx) {
+ duk_idx_t nargs;
+ duk_uint32_t len;
+ duk_bool_t have_delcount;
+ duk_int_t item_count;
+ duk_int_t act_start;
+ duk_int_t del_count;
+ duk_int_t i, n;
+
+ DUK_UNREF(have_delcount);
+
+ nargs = duk_get_top(ctx);
+ if (nargs < 2) {
+ duk_set_top(ctx, 2);
+ nargs = 2;
+ have_delcount = 0;
+ } else {
+ have_delcount = 1;
+ }
+
+ /* XXX: len >= 0x80000000 won't work below because we need to be
+ * able to represent -len.
+ */
+ len = duk__push_this_obj_len_u32_limited(ctx);
+
+ act_start = duk_to_int_clamped(ctx, 0, -((duk_int_t) len), (duk_int_t) len);
+ if (act_start < 0) {
+ act_start = len + act_start;
+ }
+ DUK_ASSERT(act_start >= 0 && act_start <= (duk_int_t) len);
+
+#ifdef DUK_USE_NONSTD_ARRAY_SPLICE_DELCOUNT
+ if (have_delcount) {
+#endif
+ del_count = duk_to_int_clamped(ctx, 1, 0, len - act_start);
+#ifdef DUK_USE_NONSTD_ARRAY_SPLICE_DELCOUNT
+ } else {
+ /* E5.1 standard behavior when deleteCount is not given would be
+ * to treat it just like if 'undefined' was given, which coerces
+ * ultimately to 0. Real world behavior is to splice to the end
+ * of array, see test-bi-array-proto-splice-no-delcount.js.
+ */
+ del_count = len - act_start;
+ }
+#endif
+
+ DUK_ASSERT(nargs >= 2);
+ item_count = (duk_int_t) (nargs - 2);
+
+ DUK_ASSERT(del_count >= 0 && del_count <= (duk_int_t) len - act_start);
+ DUK_ASSERT(del_count + act_start <= (duk_int_t) len);
+
+ /* For now, restrict result array into 32-bit length range. */
+ if (((duk_double_t) len) - ((duk_double_t) del_count) + ((duk_double_t) item_count) > (duk_double_t) DUK_UINT32_MAX) {
+ DUK_D(DUK_DPRINT("Array.prototype.splice() would go beyond 32-bit length, throw"));
+ return DUK_RET_RANGE_ERROR;
+ }
+
+ duk_push_array(ctx);
+
+ /* stack[0] = start
+ * stack[1] = deleteCount
+ * stack[2...nargs-1] = items
+ * stack[nargs] = ToObject(this) -3
+ * stack[nargs+1] = ToUint32(length) -2
+ * stack[nargs+2] = result array -1
+ */
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+
+ /* Step 9: copy elements-to-be-deleted into the result array */
+
+ for (i = 0; i < del_count; i++) {
+ if (duk_get_prop_index(ctx, -3, (duk_uarridx_t) (act_start + i))) {
+ duk_xdef_prop_index_wec(ctx, -2, i); /* throw flag irrelevant (false in std alg) */
+ } else {
+ duk_pop(ctx);
+ }
+ }
+ duk_push_u32(ctx, (duk_uint32_t) del_count);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
+
+ /* Steps 12 and 13: reorganize elements to make room for itemCount elements */
+
+ if (item_count < del_count) {
+ /* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 1
+ * -> [ A B F G H ] (conceptual intermediate step)
+ * -> [ A B . F G H ] (placeholder marked)
+ * [ A B C F G H ] (actual result at this point, C will be replaced)
+ */
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+
+ n = len - del_count;
+ for (i = act_start; i < n; i++) {
+ if (duk_get_prop_index(ctx, -3, (duk_uarridx_t) (i + del_count))) {
+ duk_put_prop_index(ctx, -4, (duk_uarridx_t) (i + item_count));
+ } else {
+ duk_pop(ctx);
+ duk_del_prop_index(ctx, -3, (duk_uarridx_t) (i + item_count));
+ }
+ }
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+
+ /* loop iterator init and limit changed from standard algorithm */
+ n = len - del_count + item_count;
+ for (i = len - 1; i >= n; i--) {
+ duk_del_prop_index(ctx, -3, (duk_uarridx_t) i);
+ }
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+ } else if (item_count > del_count) {
+ /* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 4
+ * -> [ A B F G H ] (conceptual intermediate step)
+ * -> [ A B . . . . F G H ] (placeholder marked)
+ * [ A B C D E F F G H ] (actual result at this point)
+ */
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+
+ /* loop iterator init and limit changed from standard algorithm */
+ for (i = len - del_count - 1; i >= act_start; i--) {
+ if (duk_get_prop_index(ctx, -3, (duk_uarridx_t) (i + del_count))) {
+ duk_put_prop_index(ctx, -4, (duk_uarridx_t) (i + item_count));
+ } else {
+ duk_pop(ctx);
+ duk_del_prop_index(ctx, -3, (duk_uarridx_t) (i + item_count));
+ }
+ }
+
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+ } else {
+ /* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 3
+ * -> [ A B F G H ] (conceptual intermediate step)
+ * -> [ A B . . . F G H ] (placeholder marked)
+ * [ A B C D E F G H ] (actual result at this point)
+ */
+ }
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+
+ /* Step 15: insert itemCount elements into the hole made above */
+
+ for (i = 0; i < item_count; i++) {
+ duk_dup(ctx, i + 2); /* args start at index 2 */
+ duk_put_prop_index(ctx, -4, (duk_uarridx_t) (act_start + i));
+ }
+
+ /* Step 16: update length; note that the final length may be above 32 bit range
+ * (but we checked above that this isn't the case here)
+ */
+
+ duk_push_u32(ctx, len - del_count + item_count);
+ duk_put_prop_stridx(ctx, -4, DUK_STRIDX_LENGTH);
+
+ /* result array is already at the top of stack */
+ DUK_ASSERT_TOP(ctx, nargs + 3);
+ return 1;
+}
+
+/*
+ * reverse()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_reverse(duk_context *ctx) {
+ duk_uint32_t len;
+ duk_uint32_t middle;
+ duk_uint32_t lower, upper;
+ duk_bool_t have_lower, have_upper;
+
+ len = duk__push_this_obj_len_u32(ctx);
+ middle = len / 2;
+
+ /* If len <= 1, middle will be 0 and for-loop bails out
+ * immediately (0 < 0 -> false).
+ */
+
+ for (lower = 0; lower < middle; lower++) {
+ DUK_ASSERT(len >= 2);
+ DUK_ASSERT_TOP(ctx, 2);
+
+ DUK_ASSERT(len >= lower + 1);
+ upper = len - lower - 1;
+
+ have_lower = duk_get_prop_index(ctx, -2, (duk_uarridx_t) lower);
+ have_upper = duk_get_prop_index(ctx, -3, (duk_uarridx_t) upper);
+
+ /* [ ToObject(this) ToUint32(length) lowerValue upperValue ] */
+
+ if (have_upper) {
+ duk_put_prop_index(ctx, -4, (duk_uarridx_t) lower);
+ } else {
+ duk_del_prop_index(ctx, -4, (duk_uarridx_t) lower);
+ duk_pop(ctx);
+ }
+
+ if (have_lower) {
+ duk_put_prop_index(ctx, -3, (duk_uarridx_t) upper);
+ } else {
+ duk_del_prop_index(ctx, -3, (duk_uarridx_t) upper);
+ duk_pop(ctx);
+ }
+
+ DUK_ASSERT_TOP(ctx, 2);
+ }
+
+ DUK_ASSERT_TOP(ctx, 2);
+ duk_pop(ctx); /* -> [ ToObject(this) ] */
+ return 1;
+}
+
+/*
+ * slice()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_slice(duk_context *ctx) {
+ duk_uint32_t len;
+ duk_int_t start, end;
+ duk_int_t i;
+ duk_uarridx_t idx;
+ duk_uint32_t res_length = 0;
+
+ /* XXX: len >= 0x80000000 won't work below because we need to be
+ * able to represent -len.
+ */
+ len = duk__push_this_obj_len_u32_limited(ctx);
+ duk_push_array(ctx);
+
+ /* stack[0] = start
+ * stack[1] = end
+ * stack[2] = ToObject(this)
+ * stack[3] = ToUint32(length)
+ * stack[4] = result array
+ */
+
+ start = duk_to_int_clamped(ctx, 0, -((duk_int_t) len), (duk_int_t) len);
+ if (start < 0) {
+ start = len + start;
+ }
+ /* XXX: could duk_is_undefined() provide defaulting undefined to 'len'
+ * (the upper limit)?
+ */
+ if (duk_is_undefined(ctx, 1)) {
+ end = len;
+ } else {
+ end = duk_to_int_clamped(ctx, 1, -((duk_int_t) len), (duk_int_t) len);
+ if (end < 0) {
+ end = len + end;
+ }
+ }
+ DUK_ASSERT(start >= 0 && (duk_uint32_t) start <= len);
+ DUK_ASSERT(end >= 0 && (duk_uint32_t) end <= len);
+
+ idx = 0;
+ for (i = start; i < end; i++) {
+ DUK_ASSERT_TOP(ctx, 5);
+ if (duk_get_prop_index(ctx, 2, (duk_uarridx_t) i)) {
+ duk_xdef_prop_index_wec(ctx, 4, idx);
+ res_length = idx + 1;
+ } else {
+ duk_pop(ctx);
+ }
+ idx++;
+ DUK_ASSERT_TOP(ctx, 5);
+ }
+
+ duk_push_u32(ctx, res_length);
+ duk_xdef_prop_stridx(ctx, 4, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
+
+ DUK_ASSERT_TOP(ctx, 5);
+ return 1;
+}
+
+/*
+ * shift()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_shift(duk_context *ctx) {
+ duk_uint32_t len;
+ duk_uint32_t i;
+
+ len = duk__push_this_obj_len_u32(ctx);
+ if (len == 0) {
+ duk_push_int(ctx, 0);
+ duk_put_prop_stridx(ctx, 0, DUK_STRIDX_LENGTH);
+ return 0;
+ }
+
+ duk_get_prop_index(ctx, 0, 0);
+
+ /* stack[0] = object (this)
+ * stack[1] = ToUint32(length)
+ * stack[2] = elem at index 0 (retval)
+ */
+
+ for (i = 1; i < len; i++) {
+ DUK_ASSERT_TOP(ctx, 3);
+ if (duk_get_prop_index(ctx, 0, (duk_uarridx_t) i)) {
+ /* fromPresent = true */
+ duk_put_prop_index(ctx, 0, (duk_uarridx_t) (i - 1));
+ } else {
+ /* fromPresent = false */
+ duk_del_prop_index(ctx, 0, (duk_uarridx_t) (i - 1));
+ duk_pop(ctx);
+ }
+ }
+ duk_del_prop_index(ctx, 0, (duk_uarridx_t) (len - 1));
+
+ duk_push_u32(ctx, (duk_uint32_t) (len - 1));
+ duk_put_prop_stridx(ctx, 0, DUK_STRIDX_LENGTH);
+
+ DUK_ASSERT_TOP(ctx, 3);
+ return 1;
+}
+
+/*
+ * unshift()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_unshift(duk_context *ctx) {
+ duk_idx_t nargs;
+ duk_uint32_t len;
+ duk_uint32_t i;
+
+ nargs = duk_get_top(ctx);
+ len = duk__push_this_obj_len_u32(ctx);
+
+ /* stack[0...nargs-1] = unshift args (vararg)
+ * stack[nargs] = ToObject(this)
+ * stack[nargs+1] = ToUint32(length)
+ */
+
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+
+ /* Note: unshift() may operate on indices above unsigned 32-bit range
+ * and the final length may be >= 2**32. However, we restrict the
+ * final result to 32-bit range for practicality.
+ */
+
+ if (len + (duk_uint32_t) nargs < len) {
+ DUK_D(DUK_DPRINT("Array.prototype.unshift() would go beyond 32-bit length, throw"));
+ return DUK_RET_RANGE_ERROR;
+ }
+
+ i = len;
+ while (i > 0) {
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+ i--;
+ /* k+argCount-1; note that may be above 32-bit range */
+
+ if (duk_get_prop_index(ctx, -2, (duk_uarridx_t) i)) {
+ /* fromPresent = true */
+ /* [ ... ToObject(this) ToUint32(length) val ] */
+ duk_put_prop_index(ctx, -3, (duk_uarridx_t) (i + nargs)); /* -> [ ... ToObject(this) ToUint32(length) ] */
+ } else {
+ /* fromPresent = false */
+ /* [ ... ToObject(this) ToUint32(length) val ] */
+ duk_pop(ctx);
+ duk_del_prop_index(ctx, -2, (duk_uarridx_t) (i + nargs)); /* -> [ ... ToObject(this) ToUint32(length) ] */
+ }
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+ }
+
+ for (i = 0; i < (duk_uint32_t) nargs; i++) {
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+ duk_dup(ctx, i); /* -> [ ... ToObject(this) ToUint32(length) arg[i] ] */
+ duk_put_prop_index(ctx, -3, (duk_uarridx_t) i);
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+ }
+
+ DUK_ASSERT_TOP(ctx, nargs + 2);
+ duk_push_u32(ctx, len + nargs);
+ duk_dup_top(ctx); /* -> [ ... ToObject(this) ToUint32(length) final_len final_len ] */
+ duk_put_prop_stridx(ctx, -4, DUK_STRIDX_LENGTH);
+ return 1;
+}
+
+/*
+ * indexOf(), lastIndexOf()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_indexof_shared(duk_context *ctx) {
+ duk_idx_t nargs;
+ duk_int_t i, len;
+ duk_int_t from_index;
+ duk_small_int_t idx_step = duk_get_current_magic(ctx); /* idx_step is +1 for indexOf, -1 for lastIndexOf */
+
+ /* lastIndexOf() needs to be a vararg function because we must distinguish
+ * between an undefined fromIndex and a "not given" fromIndex; indexOf() is
+ * made vararg for symmetry although it doesn't strictly need to be.
+ */
+
+ nargs = duk_get_top(ctx);
+ duk_set_top(ctx, 2);
+
+ /* XXX: must be able to represent -len */
+ len = (duk_int_t) duk__push_this_obj_len_u32_limited(ctx);
+ if (len == 0) {
+ goto not_found;
+ }
+
+ /* Index clamping is a bit tricky, we must ensure that we'll only iterate
+ * through elements that exist and that the specific requirements from E5.1
+ * Sections 15.4.4.14 and 15.4.4.15 are fulfilled; especially:
+ *
+ * - indexOf: clamp to [-len,len], negative handling -> [0,len],
+ * if clamped result is len, for-loop bails out immediately
+ *
+ * - lastIndexOf: clamp to [-len-1, len-1], negative handling -> [-1, len-1],
+ * if clamped result is -1, for-loop bails out immediately
+ *
+ * If fromIndex is not given, ToInteger(undefined) = 0, which is correct
+ * for indexOf() but incorrect for lastIndexOf(). Hence special handling,
+ * and why lastIndexOf() needs to be a vararg function.
+ */
+
+ if (nargs >= 2) {
+ /* indexOf: clamp fromIndex to [-len, len]
+ * (if fromIndex == len, for-loop terminates directly)
+ *
+ * lastIndexOf: clamp fromIndex to [-len - 1, len - 1]
+ * (if clamped to -len-1 -> fromIndex becomes -1, terminates for-loop directly)
+ */
+ from_index = duk_to_int_clamped(ctx,
+ 1,
+ (idx_step > 0 ? -len : -len - 1),
+ (idx_step > 0 ? len : len - 1));
+ if (from_index < 0) {
+ /* for lastIndexOf, result may be -1 (mark immediate termination) */
+ from_index = len + from_index;
+ }
+ } else {
+ /* for indexOf, ToInteger(undefined) would be 0, i.e. correct, but
+ * handle both indexOf and lastIndexOf specially here.
+ */
+ if (idx_step > 0) {
+ from_index = 0;
+ } else {
+ from_index = len - 1;
+ }
+ }
+
+ /* stack[0] = searchElement
+ * stack[1] = fromIndex
+ * stack[2] = object
+ * stack[3] = length (not needed, but not popped above)
+ */
+
+ for (i = from_index; i >= 0 && i < len; i += idx_step) {
+ DUK_ASSERT_TOP(ctx, 4);
+
+ if (duk_get_prop_index(ctx, 2, (duk_uarridx_t) i)) {
+ DUK_ASSERT_TOP(ctx, 5);
+ if (duk_strict_equals(ctx, 0, 4)) {
+ duk_push_int(ctx, i);
+ return 1;
+ }
+ }
+
+ duk_pop(ctx);
+ }
+
+ not_found:
+ duk_push_int(ctx, -1);
+ return 1;
+}
+
+/*
+ * every(), some(), forEach(), map(), filter()
+ */
+
+#define DUK__ITER_EVERY 0
+#define DUK__ITER_SOME 1
+#define DUK__ITER_FOREACH 2
+#define DUK__ITER_MAP 3
+#define DUK__ITER_FILTER 4
+
+/* XXX: This helper is a bit awkward because the handling for the different iteration
+ * callers is quite different. This now compiles to a bit less than 500 bytes, so with
+ * 5 callers the net result is about 100 bytes / caller.
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_iter_shared(duk_context *ctx) {
+ duk_uint32_t len;
+ duk_uint32_t i;
+ duk_uarridx_t k;
+ duk_bool_t bval;
+ duk_small_int_t iter_type = duk_get_current_magic(ctx);
+ duk_uint32_t res_length = 0;
+
+ /* each call this helper serves has nargs==2 */
+ DUK_ASSERT_TOP(ctx, 2);
+
+ len = duk__push_this_obj_len_u32(ctx);
+ duk_require_callable(ctx, 0);
+ /* if thisArg not supplied, behave as if undefined was supplied */
+
+ if (iter_type == DUK__ITER_MAP || iter_type == DUK__ITER_FILTER) {
+ duk_push_array(ctx);
+ } else {
+ duk_push_undefined(ctx);
+ }
+
+ /* stack[0] = callback
+ * stack[1] = thisArg
+ * stack[2] = object
+ * stack[3] = ToUint32(length) (unused, but avoid unnecessary pop)
+ * stack[4] = result array (or undefined)
+ */
+
+ k = 0; /* result index for filter() */
+ for (i = 0; i < len; i++) {
+ DUK_ASSERT_TOP(ctx, 5);
+
+ if (!duk_get_prop_index(ctx, 2, (duk_uarridx_t) i)) {
+#if defined(DUK_USE_NONSTD_ARRAY_MAP_TRAILER)
+ /* Real world behavior for map(): trailing non-existent
+ * elements don't invoke the user callback, but are still
+ * counted towards result 'length'.
+ */
+ if (iter_type == DUK__ITER_MAP) {
+ res_length = i + 1;
+ }
+#else
+ /* Standard behavior for map(): trailing non-existent
+ * elements don't invoke the user callback and are not
+ * counted towards result 'length'.
+ */
+#endif
+ duk_pop(ctx);
+ continue;
+ }
+
+ /* The original value needs to be preserved for filter(), hence
+ * this funny order. We can't re-get the value because of side
+ * effects.
+ */
+
+ duk_dup(ctx, 0);
+ duk_dup(ctx, 1);
+ duk_dup(ctx, -3);
+ duk_push_u32(ctx, i);
+ duk_dup(ctx, 2); /* [ ... val callback thisArg val i obj ] */
+ duk_call_method(ctx, 3); /* -> [ ... val retval ] */
+
+ switch (iter_type) {
+ case DUK__ITER_EVERY:
+ bval = duk_to_boolean(ctx, -1);
+ if (!bval) {
+ /* stack top contains 'false' */
+ return 1;
+ }
+ break;
+ case DUK__ITER_SOME:
+ bval = duk_to_boolean(ctx, -1);
+ if (bval) {
+ /* stack top contains 'true' */
+ return 1;
+ }
+ break;
+ case DUK__ITER_FOREACH:
+ /* nop */
+ break;
+ case DUK__ITER_MAP:
+ duk_dup(ctx, -1);
+ duk_xdef_prop_index_wec(ctx, 4, (duk_uarridx_t) i); /* retval to result[i] */
+ res_length = i + 1;
+ break;
+ case DUK__ITER_FILTER:
+ bval = duk_to_boolean(ctx, -1);
+ if (bval) {
+ duk_dup(ctx, -2); /* orig value */
+ duk_xdef_prop_index_wec(ctx, 4, (duk_uarridx_t) k);
+ k++;
+ res_length = k;
+ }
+ break;
+ default:
+ DUK_UNREACHABLE();
+ break;
+ }
+ duk_pop_2(ctx);
+
+ DUK_ASSERT_TOP(ctx, 5);
+ }
+
+ switch (iter_type) {
+ case DUK__ITER_EVERY:
+ duk_push_true(ctx);
+ break;
+ case DUK__ITER_SOME:
+ duk_push_false(ctx);
+ break;
+ case DUK__ITER_FOREACH:
+ duk_push_undefined(ctx);
+ break;
+ case DUK__ITER_MAP:
+ case DUK__ITER_FILTER:
+ DUK_ASSERT_TOP(ctx, 5);
+ DUK_ASSERT(duk_is_array(ctx, -1)); /* topmost element is the result array already */
+ duk_push_u32(ctx, res_length);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
+ break;
+ default:
+ DUK_UNREACHABLE();
+ break;
+ }
+
+ return 1;
+}
+
+/*
+ * reduce(), reduceRight()
+ */
+
+DUK_INTERNAL duk_ret_t duk_bi_array_prototype_reduce_shared(duk_context *ctx) {
+ duk_idx_t nargs;
+ duk_bool_t have_acc;
+ duk_uint32_t i, len;
+ duk_small_int_t idx_step = duk_get_current_magic(ctx); /* idx_step is +1 for reduce, -1 for reduceRight */
+
+ /* We're a varargs function because we need to detect whether
+ * initialValue was given or not.
+ */
+ nargs = duk_get_top(ctx);
+ DUK_DDD(DUK_DDDPRINT("nargs=%ld", (long) nargs));
+
+ duk_set_top(ctx, 2);
+ len = duk__push_this_obj_len_u32(ctx);
+ if (!duk_is_callable(ctx, 0)) {
+ goto type_error;
+ }
+
+ /* stack[0] = callback fn
+ * stack[1] = initialValue
+ * stack[2] = object (coerced this)
+ * stack[3] = length (not needed, but not popped above)
+ * stack[4] = accumulator
+ */
+
+ have_acc = 0;
+ if (nargs >= 2) {
+ duk_dup(ctx, 1);
+ have_acc = 1;
+ }
+ DUK_DDD(DUK_DDDPRINT("have_acc=%ld, acc=%!T",
+ (long) have_acc, (duk_tval *) duk_get_tval(ctx, 3)));
+
+ /* For len == 0, i is initialized to len - 1 which underflows.
+ * The condition (i < len) will then exit the for-loop on the
+ * first round which is correct. Similarly, loop termination
+ * happens by i underflowing.
+ */
+
+ for (i = (idx_step >= 0 ? 0 : len - 1);
+ i < len; /* i >= 0 would always be true */
+ i += idx_step) {
+ DUK_DDD(DUK_DDDPRINT("i=%ld, len=%ld, have_acc=%ld, top=%ld, acc=%!T",
+ (long) i, (long) len, (long) have_acc,
+ (long) duk_get_top(ctx),
+ (duk_tval *) duk_get_tval(ctx, 4)));
+
+ DUK_ASSERT((have_acc && duk_get_top(ctx) == 5) ||
+ (!have_acc && duk_get_top(ctx) == 4));
+
+ if (!duk_has_prop_index(ctx, 2, (duk_uarridx_t) i)) {
+ continue;
+ }
+
+ if (!have_acc) {
+ DUK_ASSERT_TOP(ctx, 4);
+ duk_get_prop_index(ctx, 2, (duk_uarridx_t) i);
+ have_acc = 1;
+ DUK_ASSERT_TOP(ctx, 5);
+ } else {
+ DUK_ASSERT_TOP(ctx, 5);
+ duk_dup(ctx, 0);
+ duk_dup(ctx, 4);
+ duk_get_prop_index(ctx, 2, (duk_uarridx_t) i);
+ duk_push_u32(ctx, i);
+ duk_dup(ctx, 2);
+ DUK_DDD(DUK_DDDPRINT("calling reduce function: func=%!T, prev=%!T, curr=%!T, idx=%!T, obj=%!T",
+ (duk_tval *) duk_get_tval(ctx, -5), (duk_tval *) duk_get_tval(ctx, -4),
+ (duk_tval *) duk_get_tval(ctx, -3), (duk_tval *) duk_get_tval(ctx, -2),
+ (duk_tval *) duk_get_tval(ctx, -1)));
+ duk_call(ctx, 4);
+ DUK_DDD(DUK_DDDPRINT("-> result: %!T", (duk_tval *) duk_get_tval(ctx, -1)));
+ duk_replace(ctx, 4);
+ DUK_ASSERT_TOP(ctx, 5);
+ }
+ }
+
+ if (!have_acc) {
+ goto type_error;
+ }
+
+ DUK_ASSERT_TOP(ctx, 5);
+ return 1;
+
+ type_error:
+ return DUK_RET_TYPE_ERROR;
+}
+
+#undef DUK__ARRAY_MID_JOIN_LIMIT
+
+#undef DUK__ITER_EVERY
+#undef DUK__ITER_SOME
+#undef DUK__ITER_FOREACH
+#undef DUK__ITER_MAP
+#undef DUK__ITER_FILTER