Stdlib: ReflectionParameter — attributes + type + default value parity (ext/reflection/php_reflection.c)

[PurHur]

Category

stdlib · php-src-strict

Problem

ReflectionParameter parity gaps vs Zend: parameter attributes, type information (nullable / union / intersection / DNF), and default value introspection must match php-src. PHPUnit, DI containers, and this compiler's own reflection tests depend on ReflectionParameter::getAttributes(), getType(), isDefaultValueAvailable(), and getDefaultValue().

Current VM reflection returns incomplete metadata for parameters (attributes on params were deferred from the initial attribute rollout).

php-src reference

• php/php-src ext/reflection/php_reflection.c — reflection_parameter_* handlers
• php/php-src Zend/zend_attributes.c — ZEND_ATTRIBUTE_TARGET_PARAMETER
• php/php-src Zend/zend_compile.c — arg info, default values, zend_compile_arg_info
• php/php-src Zend/zend_ast.c — default constant expression serialization

Repro (failure today)

<?php
declare(strict_types=1);

#[Attribute]
final class A {
    public function __construct(public string $x) {}
}

class C {
    public function f(#[A('p')] ?int $p = 42, string ...$rest) {}
}

$rm = new ReflectionMethod(C::class, 'f');
$rp = $rm->getParameters()[0];

echo $rp->getName(), "\n";
echo ($rp->hasType() ? $rp->getType()->__toString() : 'no-type'), "\n";
echo ($rp->isDefaultValueAvailable() ? 'has-default' : 'no-default'), "\n";
if ($rp->isDefaultValueAvailable()) {
    var_export($rp->getDefaultValue());
    echo "\n";
}
$attrs = $rp->getAttributes(A::class);
echo count($attrs), "\n";
if ($attrs) {
    $inst = $attrs[0]->newInstance();
    echo $inst->x, "\n";
}

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

Check	Zend	VM today
getName()	p	may work
getType()	?int	incomplete
getDefaultValue()	42	missing/wrong
getAttributes(A::class)	count 1, x=p	count 0 ❌

Scope (PHP-in-PHP)

Path	Work
ext/standard/VmReflection.php	ReflectionParameter methods
lib/VM/BuiltinClasses.php	arg metadata from compile table
lib/VM/ReflectionSupport.php	attribute materialization for ZEND_ATTRIBUTE_TARGET_PARAMETER
script/capability-matrix.php	reflection rows

Done when (php-src-strict)

• Repro output matches Zend on all four checks above
• Variadic ...$rest parameter: isVariadic() true; no false default
• Union/intersection/DNF parameter types stringify like Zend
• test/compliance/cases/stdlib/reflection_parameter_attributes.phpt green
• ./script/ci-fast.sh --filter reflection_parameter green

Related

• Stdlib: ReflectionProperty — attributes + type + visibility parity (ext/reflection/php_reflection.c) #4384 ReflectionMethod · Stdlib: ReflectionClassConstant — visibility, value, and attributes parity (ext/reflection/php_reflection.c) #4386 ReflectionClassConstant · php-in-php: #[\Deprecated] builtin attribute — register in ext/standard not lib/VM/AttributeSupport (zend_attributes.stub.php) #7145 attributes · #1492

[PurHur]

Implementation-ready addendum (parity architect, Jun 2026)

Narrow repro: built-in #[\SensitiveParameter] on parameters

Tracked separately as #5152 (VM fatal today).

<?php
function f(#[\SensitiveParameter] $p) {}
$rp = (new ReflectionFunction('f'))->getParameters()[0];
echo $rp->getAttributes()[0]->getName(), "\n";

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php repro.php          # Zend: SensitiveParameter
php bin/vm.php repro.php   # Method call on non-object
'

Done when for #5152: getAttributes()[0] is a ReflectionAttribute with getName() === 'SensitiveParameter'.

This umbrella (#4385) remains open for typed parameters, defaults, and user-defined #[A] attributes in the main repro.

[PurHur]

claim: cursor-agent-lane-c — starting this run (ReflectionParameter::getAttributes for #[\SensitiveParameter])

[PurHur]

Merged via #17773.

Verification
```bash
./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/vm.php test/repro/reflection_parameter_4385.php
vendor/bin/phpunit --filter reflection_parameter_introspection
'
```

VM output matches Zend for name/type/default/attributes/variadic probes. Compliance guard reflection_parameter_introspection.phpt green on VM+JIT.

Note: Umbrella #4385 remains open for remaining gaps (union/DNF parameter types, promoted-param edge cases) — this PR closes the core repro table.