Bootstrap: highlight_string() / highlight_file() — native tokenizer HTML without host highlight_* (ext/standard/url.c)

[PurHur]

Category

bootstrap | stdlib

Problem

highlight_string() and highlight_file() VM implementations delegate to host Zend highlight_string() / highlight_file() via ext/standard/VmHighlight.php. Bootstrap/self-host binaries must not call host PHP builtins for syntax highlighting — same class of gap as #4795 (json), #4790 (hash).

php-src reference

• php/php-src ext/standard/url.c — PHP_FUNCTION(highlight_string)
• php/php-src ext/standard/php_highlight.h — tokenizer → HTML renderer

Repro

<?php
echo highlight_string('<?php echo 1;', true);

# Zend reference
php repro_highlight.php | head -3

# Native compiler (must not call \highlight_string)
php bin/vm.php repro_highlight.php
# Today: LogicException VM-only or host delegation when Zend missing

Scope (this repo)

• ext/standard/VmHighlight.php — port mini highlighter or bundle tokenizer color table
• ext/standard/highlight_string.php, highlight_file.php
• lib/JIT/Builtin/* — phase 2 JIT (Stdlib: highlight_string/highlight_file/show_source — JIT/AOT lowering (phase 2 of #3164) #4366) after VM native path exists
• Drop host \highlight_string from bootstrap inventory

Done when

• php bin/vm.php repro_highlight.php prints HTML matching Zend structure on a fixed snippet without loading host highlight_*.
• php script/bootstrap-inventory.php --check no longer flags host delegation for these functions.

Related

• Stdlib: highlight_string/highlight_file/show_source — JIT/AOT lowering (phase 2 of #3164) #4366 (JIT/AOT phase 2)
• Self-host Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492, Bootstrap: VmJson json_encode/json_decode — native serialization without host json extension #4795

[PurHur]

claim: PHP Runtime → PHP — starting this run (#4824: native VmHighlight via LanguageScanner, delete host \highlight_string delegation).

[PurHur]

Merged via #7655.

Verification:

• vendor/bin/phpunit --filter VmHighlightTest — OK (3 tests)
• VM repro: highlight_string('<?php echo 1; ?>', true) returns <code> + <span> HTML without host \highlight_string()

PHP-in-PHP: HighlightEngine.php uses LanguageScanner; removed host delegation from VmHighlight.php.