Replace Hoa with a regex parser generated by phplrt

.typos.toml

@@ -1,6 +1,8 @@
 [files]
 extend-exclude = [
     ".git/",
+    # generated by `make regex-parser`, contains lexer regexes
+    "src/Type/Regex/Parser/RegexParser.php",
 ]
 ignore-hidden = false
 

CLAUDE.md

@@ -185,6 +185,17 @@ Collects structural information about a class during AST traversal: properties,
 - **`PHPStan\Cache`** - Caching infrastructure
 - **`PHPStan\Testing`** - `RuleTestCase`, `TypeInferenceTestCase`, and other test utilities
 
+### Regex parser (`src/Type/Regex/`)
+
+`RegexGroupParser` parses regex patterns to infer `preg_match()` array shapes (via `RegexArrayShapeMatcher`) and `IgnoredRegexValidator` uses it to validate `ignoreErrors` patterns. The parser itself is generated by [phplrt](https://github.com/phplrt/phplrt):
+
+- **Grammar**: `build/regex-parser/RegexGrammar.pp3` (phplrt `.pp3` format, derived from Hoa's regex grammar). The reducers in the grammar build a tree of `PHPStan\Type\Regex\Parser\RegexNode` objects (`#capturing`, `#alternation`, `#quantification`, `token`, ...) that `RegexGroupParser` walks.
+- **Generated parser**: `src/Type/Regex/Parser/RegexParser.php`. Never edit it by hand. Change the grammar and regenerate, then commit both files together.
+- **Regenerating**: `make regex-parser`. It installs the phplrt compiler into `build/regex-parser/vendor` (separate `build/regex-parser/composer.json`, needs PHP 8.4+) and runs `build/regex-parser/generate.php`. The script targets PHP 8.1 syntax and post-processes the output so that the PHAR's PHP 7.4 downgrader can handle it (first-class callables become `\Closure::fromCallable()`) and adds `@throws` to `parse()`.
+- **Runtime**: the generated parser only needs the phplrt runtime, which comes from the `ondrejmirtes/phplrt-runtime` fork (a PHP 7.4 compatible downgrade of the `phplrt/*` runtime packages that replaces them). The compiler is a build-time dependency only and is never shipped.
+- Parse failures throw `Phplrt\Contracts\Parser\Exception\ParserExceptionInterface` or `RegexSyntaxException`; callers treat both as "pattern not supported" and infer no shape.
+- After changing the grammar or `RegexGroupParser`, run the regex tests: `tests/PHPStan/Analyser/nsrt/preg_*.php`, `tests/PHPStan/Type/Php/`, `tests/PHPStan/Type/Regex/` and `tests/PHPStan/Rules/Regexp/`.
+
 ## Extension points
 
 PHPStan is highly extensible. Key extension interfaces:
@@ -339,4 +350,4 @@ When adding or editing PHPDoc comments in this codebase, follow these guidelines
 - `nette/neon` - Configuration file format
 - `react/child-process`, `react/async` - Parallel analysis
 - `symfony/console` - CLI interface
-- `hoa/compiler` - Used for regex type parsing
+- `ondrejmirtes/phplrt-runtime` - PHP 7.4 compatible fork of the phplrt runtime, runs the regex parser generated from `build/regex-parser/RegexGrammar.pp3` (`make regex-parser`)

Makefile

@@ -177,6 +177,14 @@ phpstan-generate-baseline-php:
 phpstan-pro:
 	php -d memory_limit=450M bin/phpstan --pro
 
+# Regenerates src/Type/Regex/Parser/RegexParser.php from
+# build/regex-parser/RegexGrammar.pp3 with the phplrt compiler. The compiler
+# needs PHP 8.4+, the generated parser only needs the phplrt runtime.
+.PHONY: regex-parser
+regex-parser:
+	composer install --working-dir build/regex-parser
+	php build/regex-parser/generate.php
+
 name-collision:
 	php vendor/bin/detect-collisions --configuration build/collision-detector.json
 

bin/phpstan

@@ -52,13 +52,6 @@ use Symfony\Component\Console\Helper\ProgressBar;
 	}
 	$devOrPharLoader->unregister();
 
-	// fix missing key for vendor/hoa/protocol/Wrapper.php
-	$existingComposerAutoloadFiles = $GLOBALS['__composer_autoload_files'] ?? [];
-	$GLOBALS['__composer_autoload_files'] = array_merge(
-		$existingComposerAutoloadFiles,
-		array_fill_keys(['3e76f7f02b41af8cea96018933f6b7e3'], true),
-	);
-
 	$autoloaderInWorkingDirectory = $vendorDirectory . '/autoload.php';
 	$composerAutoloaderProjectPaths = [];
 

build/phpstan.neon

@@ -41,6 +41,7 @@ parameters:
 		- ../tests/PHPStan/Rules/Properties/UninitializedPropertyRuleTest.php
 		- ../tests/PHPStan/Command/IgnoredRegexValidatorTest.php
 		- ../src/Command/IgnoredRegexValidator.php
+		- ../src/Type/Regex/Parser/RegexParser.php
 	exceptions:
 		uncheckedExceptionClasses:
 			- 'PHPStan\ShouldNotHappenException'

build/regex-parser/.gitignore

@@ -0,0 +1 @@
+vendor