Stdlib: imap_mutf7_to_utf8()/imap_utf8_to_mutf7() missing when IMAP advertised (ext/imap/php_imap.stub.php)

[PurHur]

Category

enhancement · php-src-strict · IMAP surface · pillar 4

Problem

extension_loaded("imap") / imap_open are advertised, but Modified UTF-7 mailbox-name converters from php-src are absent. Distinct from #27681 (imap_utf7_decode / imap_utf7_encode — different API) and from #27674 / #27680 (imap_is_open / imap_timeout).

Verified 2026-08-05 on tip 49577690f inside ./script/docker-exec.sh.

Symbol	Zend (php-src stub)	VM (IMAP advertised)
extension_loaded("imap")	(host may lack ext)	true
function_exists("imap_open")	—	true
function_exists("imap_mutf7_to_utf8")	present in stubs	false
function_exists("imap_utf8_to_mutf7")	present in stubs	false

php-src reference

• php/php-src ext/imap/php_imap.stub.php — imap_mutf7_to_utf8(string $string): string|false, imap_utf8_to_mutf7(string $string): string|false
• php/php-src ext/imap/php_imap.c — Modified UTF-7 encode/decode handlers

PHP implementation target

• ext/imap/ PHP implementations + Module registration + Reflection stubs matching php-src
• Prefer pure PHP Modified UTF-7 codec (no new runtime/*.c); wire JIT/AOT via existing Internal pattern
• PHP-in-PHP first

Repro

./script/docker-exec.sh -- bash -lc '
cat > /tmp/imap_mutf7.php <<'"'"'PHP'"'"'
<?php
echo "ext=", extension_loaded("imap") ? "Y" : "N", "\n";
echo "open=", function_exists("imap_open") ? "Y" : "N", "\n";
echo "mutf7_to_utf8=", function_exists("imap_mutf7_to_utf8") ? "Y" : "N", "\n";
echo "utf8_to_mutf7=", function_exists("imap_utf8_to_mutf7") ? "Y" : "N", "\n";
if (function_exists("imap_utf8_to_mutf7") && function_exists("imap_mutf7_to_utf8")) {
  $m = imap_utf8_to_mutf7("Test");
  echo "round=", imap_mutf7_to_utf8($m), "\n";
}
PHP
php bin/vm.php /tmp/imap_mutf7.php
'

Done when

• Both functions exist when IMAP is advertised; Reflection names/types match php-src stubs
• Round-trip / known Modified UTF-7 vectors match Zend (or documented subset with compliance .phpt)
• VM + JIT agree; php-src-strict; no php-compiler-strict shortcut

Gate context (2026-08-05)

• user_release_ready: no — spine coverage missing SscanfStrtolApply.php; north-star5-fast red

[PurHur]

claim: PHP Compiler STD Lib Advanced — batch (issues #27764 #27765 #27780 #27820 #27821)

IMAP surface batch (mutf7 → mail_compose → copy/move → aliases → ACL trio). Shipping sequential PRs; starting #27764.

[PurHur]

claim: PHP Compiler STD Lib Advanced — batch (issues #27681, #27764, #27765, #27780, #27820)

Queued after #27681 (shares Modified UTF-7 helper).

[PurHur]

release: PHP Compiler STD Lib Advanced — deferring to the earlier claim (06:39 UTC) on this issue. Keeping #27681 (imap_utf7_encode/decode) only in this run.

[PurHur]

claim: PHP Compiler STD Lib Advanced — consolidating with #27681

Same Modified UTF-7 helper (VmImapMutf7); shipping both utf7_* and mutf7 pair in one PR to avoid worktree collision. Prior release comment superseded.

[PurHur]

merged via #28068

Verification:

• PHP_COMPILER_ENABLE_IMAP=1 php bin/vm.php test/repro/issue_27764_*.php green
• bootstrap-inventory --check OK 7109/7109
• codec vectors match Zend mb_convert_encoding(..., 'UTF7-IMAP')