Stdlib: highlight_string() / highlight_file() — syntax-highlighted output (ext/standard parity)

[PurHur]

Category

stdlib · php-src-strict · spec refresh 2026-06-20

Problem

highlight_string() / highlight_file() / show_source() (#3447) VM builtins now exist (ext/standard/VmHighlight.php, highlight_string.php, highlight_file.php), but parity is incomplete:

1. Compile — highlight_file(__DIR__ . '/x.php') fails Expr_MagicScriptConst (Regression: highlight_file()/highlight_string() __FILE__/__DIR__ args still fail compile — re-#9924/#9140 (Zend/zend_compile.c) #9973).
2. Output bytes — highlight_string($code, return: true) returns string but HTML length/markup differs from Zend (Stdlib: highlight_string() HTML markup wrong vs Zend — output length/spans differ (ext/standard/basic_functions.c) #10308 — len 269 vs 340 on maintainer repro).
3. JIT — lowering exists (JitHighlight.php); must follow VM SSOT after output parity.

Original umbrella tracked missing functions; this spec now tracks remaining php-src-strict gaps.

php-src reference

• php/php-src ext/standard/basic_functions.c — PHP_FUNCTION(highlight_string), PHP_FUNCTION(highlight_file)
• php/php-src ext/standard/php_highlight.h — shared highlighter

Repro

Output parity (#10308):

test/repro/maintainer_gap_highlight_string_bool.php

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php test/repro/maintainer_gap_highlight_string_bool.php
php bin/vm.php test/repro/maintainer_gap_highlight_string_bool.php
'

Compile parity (#9973):

test/repro/maintainer_gap_highlight_file_bool.php — VM fails compile on __DIR__ concat today.

Check	Zend	VM today
highlight_string(..., true) len	269	340
highlight_file(__DIR__.'/sample.php', true)	runs	compile fail

Scope (PHP-in-PHP)

Layer	Path
VM	ext/standard/VmHighlight.php, highlight_*.php
Compiler	#9973 magic const in call args
JIT	ext/standard/JitHighlight.php after VM green
Matrix	script/capability-matrix.php

Done when (php-src-strict)

• Stdlib: highlight_string() HTML markup wrong vs Zend — output length/spans differ (ext/standard/basic_functions.c) #10308 closed — returned HTML matches Zend byte-for-byte on maintainer repro
• Regression: highlight_file()/highlight_string() __FILE__/__DIR__ args still fail compile — re-#9924/#9140 (Zend/zend_compile.c) #9973 closed — highlight_file with __FILE__/__DIR__ operands compiles and runs
• show_source() alias parity (Stdlib: show_source() — alias of highlight_file() (ext/standard/url.c parity) #3447) if still open
• Compliance PHPTs for return=true and file path forms
• ./script/ci-fast.sh --filter highlight green

Sub-issues (claim separately)

• Regression: highlight_file()/highlight_string() __FILE__/__DIR__ args still fail compile — re-#9924/#9140 (Zend/zend_compile.c) #9973 compile magic const args
• Stdlib: highlight_string() HTML markup wrong vs Zend — output length/spans differ (ext/standard/basic_functions.c) #10308 HTML markup bytes
• Stdlib: show_source() — alias of highlight_file() (ext/standard/url.c parity) #3447 show_source alias

Related

• Regression: highlight_string()/highlight_file() — literal true second arg throws LogicException (ext/standard/url.c) #9140 · Language: highlight_file()/highlight_string() — __DIR__/__FILE__ concat fails compile (MagicScriptConst, Zend/zend_compile.c) #9924 · Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492

[PurHur]

claim: worker-lane-c — starting this run

[PurHur]

Merged via #3916

Verification: ./script/docker-exec.sh -- bash -lc 'source script/php-env.sh && vendor/bin/phpunit --filter highlight_string' → OK (1 test).

• highlight_string($code, $return) — host Zend HTML via VmHighlight
• highlight_file($path, $return) — readable host path or VmFs::fileGetContents + highlight_string; missing file returns false with Zend warning
• JIT/AOT deferred (VM-only); compliance RUNFILE highlight_run.php

[PurHur]

Merged via #7880. highlight_string/highlight_file/show_source now lower through HighlightJitHelper + JitHighlight (PHP HighlightEngine, no new C runtime). VM + JIT compliance green; verification in PR body.