From 056dda3633b6c01e9df77ef9fbca683ef4e4e800 Mon Sep 17 00:00:00 2001 From: Malte Ubl Date: Fri, 23 Oct 2026 07:35:50 -0700 Subject: [PATCH] Read Web Headers pairs without copying them, and cache their sorted list Headers kept its name/value pairs in a string array and read every element through scr_arr_get_ref (index checks, retain, release). forEach and the iterators re-sorted and rescanned the whole list for every step, and every Response or Headers built from another Headers object re-validated and re-normalized each copied pair. The Hono fixture spends 12-15% of a request there. - Pair loops read borrowed elements of the dense array (sf_pair_at). - The sort-and-combine list is cached on the Headers object and dropped by every mutation, so live iteration keeps Node's semantics. - get() of a single value returns the stored string. - Copying a Headers object whose pairs are canonical (built by the constructor or a Response) into an empty list copies the pairs; wire response headers keep the per-pair path because they may repeat names. Co-Authored-By: Claude Opus 5.5 --- .../corpus/fetch-headers-copy-cache.ts.json | 6 + packages/runtime/src/scr_fetch.c | 268 ++++++++++-------- tests/corpus/fetch-headers-copy-cache.ts | 85 ++++++ .../fetch-headers-copy-cache.ts.json | 1 + 4 files changed, 236 insertions(+), 124 deletions(-) create mode 100644 packages/compiler/test/ts7/baselines/order-parity/tests/corpus/fetch-headers-copy-cache.ts.json create mode 100644 tests/corpus/fetch-headers-copy-cache.ts create mode 100644 tests/harness/corpus-costs/fetch-headers-copy-cache.ts.json diff --git a/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/fetch-headers-copy-cache.ts.json b/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/fetch-headers-copy-cache.ts.json new file mode 100644 index 000000000..bd69651b1 --- /dev/null +++ b/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/fetch-headers-copy-cache.ts.json @@ -0,0 +1,6 @@ +{ + "order": [ + "/tests/corpus/fetch-headers-copy-cache.ts" + ], + "diags": [] +} diff --git a/packages/runtime/src/scr_fetch.c b/packages/runtime/src/scr_fetch.c index 6049a4936..48b60942e 100644 --- a/packages/runtime/src/scr_fetch.c +++ b/packages/runtime/src/scr_fetch.c @@ -172,7 +172,14 @@ struct SfStream { struct SfHeaders { size_t rc; ScrArr *pairs; + /* Fetch's "sort and combine" list of `pairs` as flat name/value pairs, + * built on the first iteration step and dropped by every mutation. */ + ScrArr *sorted; bool immutable; + /* `pairs` is in the form sf_add_converted_headers builds: lowercase valid + * names, trimmed valid UTF-8 values, one combined pair per name except + * set-cookie. Headers built from wire lines are not (duplicates stay). */ + bool canonical; }; struct SfResponse { @@ -2164,6 +2171,24 @@ static ScrDyn *sf_controller_get(void *ptr, const char *key, size_t len) { static bool sf_header_name_ok(const char *s, size_t len); +/* A borrowed element of a runtime-built header pair array. These arrays are + * only ever appended to or rewritten whole, so they are dense. */ +static inline ScrStr *sf_pair_at(ScrArr *pairs, size_t i) { + if (i < pairs->filled) return (ScrStr *)(uintptr_t)scr_arr_dense_get(pairs, i); + return (ScrStr *)scr_arr_peek_ref(pairs, (double)i); +} + +static ScrStr *sf_header_name_lower(const char *data, size_t len); + +/* `name` in lowercase, +1: the same string when it has no uppercase byte. */ +static ScrStr *sf_header_name_lower_str(ScrStr *name) { + for (size_t i = 0; i < name->len; i++) { + char c = name->data[i]; + if (c >= 'A' && c <= 'Z') return sf_header_name_lower(name->data, name->len); + } + return scr_str_retain(name); +} + static ScrStr *sf_header_name_lower(const char *data, size_t len) { char *lower = malloc(len ? len : 1); if (!lower) sf_oom(); @@ -2232,13 +2257,8 @@ static SfHeaders *sf_headers_new_response(ScrArr *raw_pairs) { size_t n = (size_t)scr_arr_len(raw_pairs); ScrArr *pairs = scr_arr_new(SCR_ELEM_STR, n); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *raw_name = scr_arr_get_ref(raw_pairs, (double)i); - scr_arr_push_ref( - pairs, sf_header_name_lower(raw_name->data, raw_name->len)); - scr_str_release(raw_name); - ScrStr *raw = scr_arr_get_ref(raw_pairs, (double)(i + 1)); - scr_arr_push_ref(pairs, sf_latin1_to_utf8(raw)); - scr_str_release(raw); + scr_arr_push_ref(pairs, sf_header_name_lower_str(sf_pair_at(raw_pairs, i))); + scr_arr_push_ref(pairs, sf_latin1_to_utf8(sf_pair_at(raw_pairs, i + 1))); } scr_arr_release(raw_pairs); return sf_headers_new(pairs, true); @@ -2252,9 +2272,17 @@ static SfHeaders *sf_headers_retain(SfHeaders *h) { static void sf_headers_release(SfHeaders *h) { if (!h || --h->rc > 0) return; scr_arr_release(h->pairs); + if (h->sorted) scr_arr_release(h->sorted); free(h); } +/* Every change to h->pairs goes through here first. */ +static void sf_headers_changed(SfHeaders *h) { + if (!h->sorted) return; + scr_arr_release(h->sorted); + h->sorted = NULL; +} + static void *sf_headers_retain_v(void *p) { return sf_headers_retain((SfHeaders *)p); } @@ -2294,7 +2322,7 @@ static ScrStr *sf_headers_name(const ScrDyn *value, const char *method) { scr_str_release(raw); return NULL; } - ScrStr *out = sf_header_name_lower(raw->data, raw->len); + ScrStr *out = sf_header_name_lower_str(raw); scr_str_release(raw); return out; } @@ -2305,40 +2333,36 @@ static bool sf_headers_key_eq(const ScrStr *left, const ScrStr *right) { } static ScrStr *sf_headers_get_value(SfHeaders *h, const ScrStr *name) { - size_t n = (size_t)scr_arr_len(h->pairs); + ScrArr *pairs = h->pairs; + size_t n = (size_t)scr_arr_len(pairs); size_t count = 0; size_t total = 0; + ScrStr *first = NULL; for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)i); - ScrStr *value = scr_arr_get_ref(h->pairs, (double)(i + 1)); - if (sf_headers_key_eq(key, name)) { - if (count > 0) total += 2; - total += value->len; - count++; - } - scr_str_release(key); - scr_str_release(value); + if (!sf_headers_key_eq(sf_pair_at(pairs, i), name)) continue; + ScrStr *value = sf_pair_at(pairs, i + 1); + if (count > 0) total += 2; + else first = value; + total += value->len; + count++; } if (count == 0) return NULL; + if (count == 1) return scr_str_retain(first); char *joined = malloc(total > 0 ? total : 1); if (!joined) sf_oom(); size_t at = 0; size_t emitted = 0; for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)i); - ScrStr *value = scr_arr_get_ref(h->pairs, (double)(i + 1)); - if (sf_headers_key_eq(key, name)) { - if (emitted > 0) { - joined[at++] = ','; - joined[at++] = ' '; - } - memcpy(joined + at, value->data, value->len); - at += value->len; - emitted++; + if (!sf_headers_key_eq(sf_pair_at(pairs, i), name)) continue; + ScrStr *value = sf_pair_at(pairs, i + 1); + if (emitted > 0) { + joined[at++] = ','; + joined[at++] = ' '; } - scr_str_release(key); - scr_str_release(value); + memcpy(joined + at, value->data, value->len); + at += value->len; + emitted++; } ScrStr *out = scr_str_new(joined, total); free(joined); @@ -2348,17 +2372,17 @@ static ScrStr *sf_headers_get_value(SfHeaders *h, const ScrStr *name) { static void sf_headers_delete_name(SfHeaders *h, const ScrStr *name) { ScrArr *old = h->pairs; size_t n = (size_t)scr_arr_len(old); + bool present = false; + for (size_t i = 0; i + 1 < n && !present; i += 2) + present = sf_headers_key_eq(sf_pair_at(old, i), name); + if (!present) return; + sf_headers_changed(h); ScrArr *next = scr_arr_new(SCR_ELEM_STR, n); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(old, (double)i); - ScrStr *value = scr_arr_get_ref(old, (double)(i + 1)); - if (sf_headers_key_eq(key, name)) { - scr_str_release(key); - scr_str_release(value); - continue; - } - scr_arr_push_ref(next, key); - scr_arr_push_ref(next, value); + ScrStr *key = sf_pair_at(old, i); + if (sf_headers_key_eq(key, name)) continue; + scr_arr_push_ref(next, scr_str_retain(key)); + scr_arr_push_ref(next, scr_str_retain(sf_pair_at(old, i + 1))); } h->pairs = next; scr_arr_release(old); @@ -2399,15 +2423,13 @@ static bool sf_headers_convert_pair( * Fetch-specific semicolon separator for Cookie. */ static void sf_headers_append_pair( SfHeaders *h, ScrStr *name, ScrStr *value) { + sf_headers_changed(h); if (!(name->len == 10 && memcmp(name->data, "set-cookie", 10) == 0)) { size_t n = (size_t)scr_arr_len(h->pairs); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)i); - bool match = sf_headers_key_eq(key, name); - scr_str_release(key); - if (!match) continue; + if (!sf_headers_key_eq(sf_pair_at(h->pairs, i), name)) continue; - ScrStr *previous = scr_arr_get_ref(h->pairs, (double)(i + 1)); + ScrStr *previous = sf_pair_at(h->pairs, i + 1); const char *separator = name->len == 6 && memcmp(name->data, "cookie", 6) == 0 ? "; " @@ -2420,7 +2442,6 @@ static void sf_headers_append_pair( memcpy(joined_data + previous->len + 2, value->data, value->len); ScrStr *joined = scr_str_new(joined_data, joined_len); free(joined_data); - scr_str_release(previous); scr_str_release(name); scr_str_release(value); scr_arr_set_ref(h->pairs, (double)(i + 1), joined); @@ -2447,7 +2468,7 @@ static ScrStr **sf_headers_sorted_names(SfHeaders *h, size_t *count_out) { if (capacity && !names) sf_oom(); size_t count = 0; for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)i); + ScrStr *key = sf_pair_at(h->pairs, i); bool seen = false; for (size_t j = 0; j < count; j++) { if (sf_headers_key_eq(names[j], key)) { @@ -2455,8 +2476,7 @@ static ScrStr **sf_headers_sorted_names(SfHeaders *h, size_t *count_out) { break; } } - if (seen) scr_str_release(key); - else names[count++] = key; + if (!seen) names[count++] = key; } if (count > 1) { qsort(names, count, sizeof *names, &sf_headers_name_cmp); @@ -2469,44 +2489,44 @@ static bool sf_headers_is_set_cookie(const ScrStr *name) { return name->len == 10 && memcmp(name->data, "set-cookie", 10) == 0; } -/* The `index`th entry of Fetch's "sort and combine" list: names in - * byte order, each with its combined value, except that every set-cookie - * value is its own entry (in insertion order), as Node's Headers - * iterator yields them. False past the end. Outputs are +1. */ +/* Fetch's "sort and combine" list as flat name/value pairs: names in byte + * order, each with its combined value, except that every set-cookie value + * is its own entry (in insertion order), as Node's Headers iterator yields + * them. Cached until the next mutation; borrowed. */ +static ScrArr *sf_headers_sorted(SfHeaders *h) { + if (h->sorted) return h->sorted; + size_t count = 0; + ScrStr **names = sf_headers_sorted_names(h, &count); /* borrowed names */ + size_t n = (size_t)scr_arr_len(h->pairs); + ScrArr *sorted = scr_arr_new(SCR_ELEM_STR, n); + for (size_t i = 0; i < count; i++) { + if (!sf_headers_is_set_cookie(names[i])) { + scr_arr_push_ref(sorted, scr_str_retain(names[i])); + scr_arr_push_ref(sorted, sf_headers_get_value(h, names[i])); + continue; + } + for (size_t j = 0; j + 1 < n; j += 2) { + if (!sf_headers_is_set_cookie(sf_pair_at(h->pairs, j))) continue; + scr_arr_push_ref(sorted, scr_str_retain(names[i])); + scr_arr_push_ref(sorted, scr_str_retain(sf_pair_at(h->pairs, j + 1))); + } + } + free(names); + h->sorted = sorted; + return sorted; +} + +/* The `index`th entry of the sort-and-combine list (sf_headers_sorted). + * False past the end. Outputs are +1. */ static bool sf_headers_sorted_entry(SfHeaders *h, size_t index, ScrStr **name_out, ScrStr **value_out) { - size_t count = 0; - ScrStr **names = sf_headers_sorted_names(h, &count); - bool found = false; - size_t at = 0; - for (size_t i = 0; i < count && !found; i++) { - if (!sf_headers_is_set_cookie(names[i])) { - if (at == index) { - *name_out = scr_str_retain(names[i]); - *value_out = sf_headers_get_value(h, names[i]); - found = true; - } - at++; - continue; - } - size_t n = (size_t)scr_arr_len(h->pairs); - for (size_t j = 0; j + 1 < n && !found; j += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)j); - bool match = sf_headers_is_set_cookie(key); - scr_str_release(key); - if (!match) continue; - if (at == index) { - *name_out = scr_str_retain(names[i]); - *value_out = scr_arr_get_ref(h->pairs, (double)(j + 1)); - found = true; - } - at++; - } - } - for (size_t j = 0; j < count; j++) scr_str_release(names[j]); - free(names); - return found; + ScrArr *sorted = sf_headers_sorted(h); + size_t entries = (size_t)scr_arr_len(sorted) / 2; + if (index >= entries) return false; + *name_out = scr_str_retain(sf_pair_at(sorted, 2 * index)); + *value_out = scr_str_retain(sf_pair_at(sorted, 2 * index + 1)); + return true; } /* One step of a live Headers iterator (entries, keys or values): the @@ -2570,14 +2590,8 @@ static ScrDyn *sf_headers_invoke(void *ptr, ScrDyn *self, ScrDyn *out = scr_dyn_new_arr(); size_t n = (size_t)scr_arr_len(h->pairs); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(h->pairs, (double)i); - ScrStr *value = scr_arr_get_ref(h->pairs, (double)(i + 1)); - if (key->len == 10 && - memcmp(key->data, "set-cookie", 10) == 0) { - scr_dyn_arr_push(out, scr_dyn_new_str(value)); - } - scr_str_release(key); - scr_str_release(value); + if (sf_headers_is_set_cookie(sf_pair_at(h->pairs, i))) + scr_dyn_arr_push(out, scr_dyn_new_str(sf_pair_at(h->pairs, i + 1))); } return out; } @@ -3323,14 +3337,13 @@ static bool sf_pairs_have(ScrArr *pairs, const char *name) { size_t n = (size_t)scr_arr_len(pairs); size_t want = strlen(name); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = (ScrStr *)scr_arr_get_ref(pairs, (double)i); + ScrStr *key = sf_pair_at(pairs, i); bool same = key->len == want; for (size_t j = 0; j < want && same; j++) { char c = key->data[j]; if (c >= 'A' && c <= 'Z') c = (char)(c - 'A' + 'a'); same = c == name[j]; } - scr_str_release(key); if (same) return true; } return false; @@ -3437,11 +3450,14 @@ static ScrStr *sf_trim_header_value(const ScrStr *value) { (value->data[end - 1] == ' ' || value->data[end - 1] == '\t')) { end--; } + if (start == 0 && end == value->len) return scr_str_retain((ScrStr *)value); return scr_str_new(value->data + start, end - start); } -static bool sf_push_header(ScrArr *pairs, const char *name, size_t name_len, +static bool sf_push_header(ScrArr *pairs, ScrStr *name_str, ScrStr *value, bool request_guard) { + const char *name = name_str->data; + size_t name_len = name_str->len; if (!sf_header_name_ok(name, name_len)) { ScrStr *display = scr_str_new(name, name_len); sf_headers_invalid("append", display, "name"); @@ -3467,7 +3483,7 @@ static bool sf_push_header(ScrArr *pairs, const char *name, size_t name_len, if (!sf_header_name_ci(name, name_len, "set-cookie")) { size_t n = (size_t)scr_arr_len(pairs); for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *key = scr_arr_get_ref(pairs, (double)i); + ScrStr *key = sf_pair_at(pairs, i); bool match = key->len == name_len; for (size_t j = 0; j < name_len && match; j++) { unsigned char a = (unsigned char)key->data[j]; @@ -3476,11 +3492,9 @@ static bool sf_push_header(ScrArr *pairs, const char *name, size_t name_len, if (b >= 'A' && b <= 'Z') b = (unsigned char)(b - 'A' + 'a'); match = a == b; } - scr_str_release(key); if (!match) continue; - ScrStr *previous = - scr_arr_get_ref(pairs, (double)(i + 1)); + ScrStr *previous = sf_pair_at(pairs, i + 1); const char *separator = sf_header_name_ci(name, name_len, "cookie") ? "; " : ", "; size_t separator_len = 2; @@ -3494,7 +3508,6 @@ static bool sf_push_header(ScrArr *pairs, const char *name, size_t name_len, normalized->data, normalized->len); ScrStr *joined = scr_str_new(joined_data, joined_len); free(joined_data); - scr_str_release(previous); scr_str_release(normalized); if (request_guard && !sf_request_header_ok(name, name_len, joined)) { scr_str_release(joined); @@ -3513,8 +3526,8 @@ static bool sf_push_header(ScrArr *pairs, const char *name, size_t name_len, scr_arr_push_ref( pairs, request_guard - ? scr_str_new(name, name_len) - : sf_header_name_lower(name, name_len)); + ? scr_str_retain(name_str) + : sf_header_name_lower_str(name_str)); scr_arr_push_ref(pairs, normalized); return true; } @@ -3541,10 +3554,13 @@ static void sf_headers_pair_length_error(size_t len) { * leaves header-name/value syntax validation for initialization. Response * construction converts this snapshot before status/statusText and only * validates it after body extraction, matching Undici's two phases. */ -static ScrArr *sf_headers_convert_init(const ScrDyn *headers) { +/* *canonical_out reports that the result copies a canonical Headers + * object's pairs (SfHeaders.canonical). */ +static ScrArr *sf_headers_convert_init(const ScrDyn *headers, bool *canonical_out) { + *canonical_out = false; if (headers && headers->kind == SCR_DYN_TYPED_REF) { ScrDyn *materialized = scr_dyn_typed_ref_materialize(headers); - ScrArr *converted = sf_headers_convert_init(materialized); + ScrArr *converted = sf_headers_convert_init(materialized, canonical_out); scr_dyn_release(materialized); return converted; } @@ -3635,13 +3651,9 @@ static ScrArr *sf_headers_convert_init(const ScrDyn *headers) { headers->v.handle.tag == SCR_DYNH_FETCH_HEADERS) { SfHeaders *source = (SfHeaders *)headers->v.handle.ptr; size_t n = (size_t)scr_arr_len(source->pairs); - for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *name = scr_arr_get_ref(source->pairs, (double)i); - ScrStr *value = - scr_arr_get_ref(source->pairs, (double)(i + 1)); - scr_arr_push_ref(converted, name); - scr_arr_push_ref(converted, value); - } + for (size_t i = 0; i < n - n % 2; i++) + scr_arr_push_ref(converted, scr_str_retain(sf_pair_at(source->pairs, i))); + *canonical_out = source->canonical; return converted; } /* Functions are WebIDL objects and an ordinary function has no @@ -3656,25 +3668,29 @@ fail: } static bool sf_add_converted_headers( - ScrArr *pairs, ScrArr *converted, bool request_guard) { + ScrArr *pairs, ScrArr *converted, bool request_guard, bool canonical) { size_t n = (size_t)scr_arr_len(converted); + /* Pushing canonical pairs into an empty list one by one through + * sf_push_header would reproduce them exactly. */ + if (canonical && !request_guard && scr_arr_len(pairs) == 0) { + for (size_t i = 0; i < n; i++) + scr_arr_push_ref(pairs, scr_str_retain(sf_pair_at(converted, i))); + return true; + } for (size_t i = 0; i + 1 < n; i += 2) { - ScrStr *name = scr_arr_get_ref(converted, (double)i); - ScrStr *value = scr_arr_get_ref(converted, (double)(i + 1)); - bool ok = sf_push_header( - pairs, name->data, name->len, value, request_guard); - scr_str_release(name); - scr_str_release(value); - if (!ok) return false; + if (!sf_push_header(pairs, sf_pair_at(converted, i), + sf_pair_at(converted, i + 1), request_guard)) + return false; } return true; } static bool sf_add_headers( ScrArr *pairs, const ScrDyn *headers, bool request_guard) { - ScrArr *converted = sf_headers_convert_init(headers); + bool canonical = false; + ScrArr *converted = sf_headers_convert_init(headers, &canonical); if (!converted) return false; - bool ok = sf_add_converted_headers(pairs, converted, request_guard); + bool ok = sf_add_converted_headers(pairs, converted, request_guard, canonical); scr_arr_release(converted); return ok; } @@ -4854,6 +4870,7 @@ static ScrDyn *sf_response_construct(ScrDyn *body, ScrDyn *init, SfJsonSerialize serialize) { ScrArr *header_pairs = NULL; ScrArr *converted_headers = NULL; + bool converted_canonical = false; ScrBytes *body_bytes = NULL; ScrStr *status_text = NULL; SfStream *stream = NULL; @@ -4918,7 +4935,7 @@ static ScrDyn *sf_response_construct(ScrDyn *body, ScrDyn *init, * later response-initialization step, after body extraction. */ ScrDyn *init_headers = sf_response_init_get(init, "headers", 7); if (light_ok) light_form = sf_light_header_form(init_headers, json_body, &light_record); - converted_headers = sf_headers_convert_init(init_headers); + converted_headers = sf_headers_convert_init(init_headers, &converted_canonical); scr_dyn_release(init_headers); if (!converted_headers) goto fail; @@ -5013,7 +5030,7 @@ static ScrDyn *sf_response_construct(ScrDyn *body, ScrDyn *init, header_pairs = scr_arr_new(SCR_ELEM_STR, 8); if (!sf_add_converted_headers( - header_pairs, converted_headers, false)) goto fail; + header_pairs, converted_headers, false, converted_canonical)) goto fail; scr_arr_release(converted_headers); converted_headers = NULL; @@ -5044,6 +5061,7 @@ static ScrDyn *sf_response_construct(ScrDyn *body, ScrDyn *init, response->rc = 1; response->body = stream; response->headers = sf_headers_new(header_pairs, false); + response->headers->canonical = true; response->url = scr_str_new("", 0); response->status_text = status_text; response->status = status; @@ -5159,13 +5177,15 @@ static ScrDyn *sf_request_invoke(void *ptr, ScrDyn *self, const char *method, Sc } ScrDyn *scr_fetch_headers_new(ScrDyn *init) { - ScrArr *converted = sf_headers_convert_init(init); + bool canonical = false; + ScrArr *converted = sf_headers_convert_init(init, &canonical); if (!converted) return NULL; ScrArr *pairs = scr_arr_new(SCR_ELEM_STR, 8); - bool ok = sf_add_converted_headers(pairs, converted, false); + bool ok = sf_add_converted_headers(pairs, converted, false, canonical); scr_arr_release(converted); if (!ok) { scr_arr_release(pairs); return NULL; } SfHeaders *headers = sf_headers_new(pairs, false); + headers->canonical = true; ScrDyn *result = scr_dyn_new_handle(headers, SCR_DYNH_FETCH_HEADERS); sf_headers_release(headers); return result; diff --git a/tests/corpus/fetch-headers-copy-cache.ts b/tests/corpus/fetch-headers-copy-cache.ts new file mode 100644 index 000000000..686ecfc61 --- /dev/null +++ b/tests/corpus/fetch-headers-copy-cache.ts @@ -0,0 +1,85 @@ +// Headers copies and the cached sort-and-combine list: copies are +// independent of their source, reads see every mutation, and live +// iterators re-read the current list after a change. +function dump(label: string, h: Headers): void { + const parts: string[] = []; + h.forEach((value, name) => parts.push(`${name}=${value}`)); + console.log(`${label}: ${parts.join(" | ")}`); +} + +// The corpus lib has no DOM iterable typings for Headers, so iterators +// are reached through an untyped view. +const iter = (h: Headers): any => h; + +const source = new Headers({ "X-B": " two ", "x-a": "one", Accept: "text/html" }); +source.append("accept", "application/json"); +source.append("Set-Cookie", "a=1"); +source.append("set-cookie", "b=2"); +dump("source", source); + +// A Headers copy keeps the combined values and stays separate. +const copy = new Headers(source); +source.set("x-a", "changed"); +copy.append("x-c", "three"); +dump("source after set", source); +dump("copy after append", copy); +console.log(JSON.stringify(copy.get("accept")), JSON.stringify(copy.get("set-cookie"))); +console.log(JSON.stringify(copy.getSetCookie())); + +// Copying into an empty Response and a Request, then appending a repeat. +const response = new Response("body", { headers: copy, status: 201 }); +response.headers.append("accept", "*/*"); +response.headers.append("cookie", "c=3"); +response.headers.append("Cookie", "d=4"); +dump("response", response.headers); +dump("copy unchanged", copy); +const clone = new Response(response.body, response); +dump("response clone", clone.headers); +const request = new Request("http://example.test/", { headers: copy }); +console.log("request x-b", JSON.stringify(request.headers.get("X-B"))); + +// Every read after a mutation sees it: get, has, iteration, spread. +const h = new Headers([["x-z", "z"], ["x-m", "m"]]); +console.log([...iter(h).entries()].map(([n, v]) => `${n}:${v}`).join(",")); +h.delete("x-z"); +console.log([...iter(h).keys()].join(","), h.has("x-z")); +h.delete("x-missing"); +console.log([...iter(h).values()].join(",")); +h.append("x-a", "first"); +console.log([...iter(h).entries()].map(([n, v]) => `${n}:${v}`).join(",")); +h.set("X-M", "again"); +console.log(JSON.stringify(h.get("x-m")), [...iter(h).keys()].join(",")); + +// A live iterator: mutations between steps change what comes next. +const it = iter(h).entries(); +console.log(JSON.stringify(it.next().value)); +h.append("x-0", "before"); +console.log(JSON.stringify(it.next().value)); +h.delete("x-m"); +h.append("x-zz", "after"); +console.log(JSON.stringify(it.next()), JSON.stringify(it.next())); + +// forEach that mutates as it walks. +const walk = new Headers([["b", "2"], ["d", "4"]]); +const seen: string[] = []; +walk.forEach((value, name) => { + seen.push(`${name}=${value}`); + if (name === "b") { + walk.append("c", "3"); + walk.append("a", "1"); + } + if (name === "c") walk.set("d", "four"); +}); +console.log(seen.join(" | ")); + +// Invalid input in a copy source is still rejected (plain object source). +try { + new Response("x", { headers: { "bad name": "v" } }); +} catch (error) { + console.log((error as Error).name, (error as Error).message); +} +try { + new Headers(source).append("x", "a\nb"); +} catch (error) { + console.log((error as Error).name, (error as Error).message); +} diff --git a/tests/harness/corpus-costs/fetch-headers-copy-cache.ts.json b/tests/harness/corpus-costs/fetch-headers-copy-cache.ts.json new file mode 100644 index 000000000..6057503d9 --- /dev/null +++ b/tests/harness/corpus-costs/fetch-headers-copy-cache.ts.json @@ -0,0 +1 @@ +{ "plain": 6400, "san": 9200 }