fix(runtime): built-ins/String test262 parity#4754
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Argument-coercion and whitespace fixes across String.prototype methods, lifting built-ins/String from 752 to 814 passing (zero regressions). Root causes: - split(separator, limit) skipped ToString(separator)/ToUint32(limit) and treated undefined separator as empty-string (per-char split). New js_string_split_value takes boxed args: ToUint32(limit) before ToString(separator) (spec order; either may throw), undefined -> [S], limit 0 -> [], RegExp-separator delegation. - indexOf/lastIndexOf bit-cast an object searchString as a string handle and raw-fptosi'd the position (skipping valueOf). Now ToString(searchString) via js_string_coerce before ToNumber(position) via js_string_index_to_i32 / js_number_coerce. - search/match required a RegExp arg (returned -1/null otherwise). New js_string_search_value/js_string_match_value coerce any non-RegExp arg via RegExpCreate(ToString(arg)); undefined -> empty /(?:)/. match/search now accept 0 args. (match(undefined) previously SIGSEGV'd: a null pattern pointer was deref'd by lookup_fancy_regex — now an empty StringHeader.) - trim/trimStart/trimEnd used Rust's Unicode White_Space, which excludes U+FEFF (BOM, a JS WhiteSpace) and includes U+0085 (NEL, not JS). Added an is_js_whitespace predicate matching ECMA-262 §22.1.3.32. Files: lower_string_method.rs (codegen), runtime_decls/strings_part2.rs, native_call_method.rs, regex.rs, string/slice_ops.rs, string/split.rs. built-ins/String: 752 -> 814 pass; 160 -> 102 runtime-fail; 20 -> 16 compile-fail; 0 regressions.
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Follow-up to #4754. built-ins/String 814 -> 840 passing, 0 regressions. - String.prototype.search dispatch arm returned a NaN-boxed INT32 instead of a raw f64, so `new String(s).search(x) === N` (and generic-this `__o.search = String.prototype.search` forms) strict-compared unequal to a number literal even though the index was correct. Return `i32 as f64`, matching the indexOf arm. (search 19/31 -> 31/31) - new String(...) wrapper (type Named("String")) mis-routed the Array/String shared methods indexOf/includes/slice/lastIndexOf to ArrayIndexOf/etc. (read the wrapper as an array -> -1/false). Treat the boxed String wrapper as a string in try_local_array_methods so they route to the ToString- coercing string dispatch. - replace/replaceAll did not ToString-coerce a non-RegExp searchValue or a non-function replaceValue (object args with throwing toString didn't throw, per ECMA-262 §22.1.3.19 order: searchValue before replaceValue). - concat bit-cast its args as string handles instead of ToString-coercing them, dropping `undefined`/booleans ("lego".concat(undefined) -> "lego"). Now ToString-coerces each non-static-string arg (§22.1.3.5). - padStart/padEnd bit-cast a non-string fillString, dropping it. New js_string_pad_fill ToString-coerces the fill (undefined -> default " "). Files: native_call_method.rs, string/pad.rs (runtime), lower_string_method.rs, runtime_decls/strings_part2.rs (codegen), lower/expr_call/local_array_methods.rs (HIR).
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…4755) Follow-up to #4754. built-ins/String 814 -> 840 passing, 0 regressions. - String.prototype.search dispatch arm returned a NaN-boxed INT32 instead of a raw f64, so `new String(s).search(x) === N` (and generic-this `__o.search = String.prototype.search` forms) strict-compared unequal to a number literal even though the index was correct. Return `i32 as f64`, matching the indexOf arm. (search 19/31 -> 31/31) - new String(...) wrapper (type Named("String")) mis-routed the Array/String shared methods indexOf/includes/slice/lastIndexOf to ArrayIndexOf/etc. (read the wrapper as an array -> -1/false). Treat the boxed String wrapper as a string in try_local_array_methods so they route to the ToString- coercing string dispatch. - replace/replaceAll did not ToString-coerce a non-RegExp searchValue or a non-function replaceValue (object args with throwing toString didn't throw, per ECMA-262 §22.1.3.19 order: searchValue before replaceValue). - concat bit-cast its args as string handles instead of ToString-coercing them, dropping `undefined`/booleans ("lego".concat(undefined) -> "lego"). Now ToString-coerces each non-static-string arg (§22.1.3.5). - padStart/padEnd bit-cast a non-string fillString, dropping it. New js_string_pad_fill ToString-coerces the fill (undefined -> default " "). Files: native_call_method.rs, string/pad.rs (runtime), lower_string_method.rs, runtime_decls/strings_part2.rs (codegen), lower/expr_call/local_array_methods.rs (HIR). Co-authored-by: Ralph Küpper <ralph@skelpo.com>
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Lifts built-ins/String test262 parity from 752 → 814 passing (runtime-fail 160 → 102, compile-fail 20 → 16), zero regressions (no test that passed before now fails). Differential vs Node on the pinned corpus (tc39/test262 @ 4249661388).
Root causes fixed
1.
String.prototype.split(separator, limit)argument coercion. Split skippedToString(separator)/ToUint32(limit)and treated anundefinedseparator as an empty-string separator (per-character split) instead of returning[wholeString]. Newjs_string_split_valuetakes the boxed separator + limit and follows §22.1.3.21 exactly:ToUint32(limit)runs beforeToString(separator)(spec order — either may run uservalueOf/toStringand throw),undefinedseparator →[S],limit === 0→[], and a RegExp separator delegates to the regex splitter. (~22 tests)2.
indexOf/lastIndexOfargument coercion. An objectsearchStringwas bit-cast as a string handle (→ garbage → -1) and thepositionwas raw-fptosid (skippingvalueOf). NowToString(searchString)viajs_string_coerceruns beforeToNumber(position)viajs_string_index_to_i32/js_number_coerce. (~18 tests)3.
search/matchregex coercion. Both required an actual RegExp argument (returned -1/null for a string/undefined/{toString}arg). Newjs_string_search_value/js_string_match_valuecoerce any non-RegExp arg viaRegExpCreate(ToString(arg)), withundefined→ the empty/(?:)/regex;match/searchnow also accept 0 args.match(undefined)previously SIGSEGVd — a null pattern pointer was dereferenced bylookup_fancy_regex; now an emptyStringHeaderis built. (~30 tests)4.
trim/trimStart/trimEndwhitespace set. Used Rust’s UnicodeWhite_Space, which excludes U+FEFF (BOM — a JSWhiteSpace) and includes U+0085 (NEL — not JS whitespace). Added anis_js_whitespacepredicate matching ECMA-262 §22.1.3.32 (WhiteSpace+LineTerminator). (~7 tests)Files
crates/perry-codegen/src/lower_string_method.rs— needle/position/separator/regex-arg coercion + 0-argmatch/searchcrates/perry-codegen/src/runtime_decls/strings_part2.rs— declarejs_string_search_value/js_string_match_value(thejs_string_split_valuedecl already landed on main)crates/perry-runtime/src/object/native_call_method.rs— generic-thisdispatch arms route through the coercing entriescrates/perry-runtime/src/regex.rs—coerce_search_arg_to_regex+js_string_search_value/js_string_match_valuecrates/perry-runtime/src/string/slice_ops.rs—is_js_whitespacetrimcrates/perry-runtime/src/string/split.rs—js_string_split_valueValidation
Default compile path (no env flags).
built-ins/String: 752 → 814 pass, 0 regressions. Verified manually against Node for split/indexOf/lastIndexOf/search/match/trim incl. the previously-crashing"abc".match(undefined).