Stdlib: class_implements() on enum case object — must return UnitEnum/BackedEnum (ext/standard/basic_functions.c)

[PurHur]

Category

stdlib

Problem

class_implements() accepts an object operand. On a backed enum case (E::A), Zend returns the same interface map as class_implements(E::class) (UnitEnum, BackedEnum). This compiler returns false (not an array).

#5422 tracks class_implements(E::class) (type name string). This issue is the enum case object operand only.

php-src reference

• php/php-src ext/standard/basic_functions.c — PHP_FUNCTION(class_implements), object branch
• php/php-src Zend/zend_enum.c — enum case zend_object implements UnitEnum / BackedEnum

Repro (failure today)

<?php
enum E: int { case A = 1; }
var_dump(class_implements(E::A));
var_dump(class_implements(E::class));

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php -r "enum E:int{case A=1;} var_dump(class_implements(E::A));"
php bin/vm.php -r "enum E:int{case A=1;} var_dump(class_implements(E::A));"
'

Runtime	class_implements(E::A)
Zend	array(2) { ["UnitEnum"]=>... ["BackedEnum"]=>... }
vm.php today	bool(false)

Scope (this repo)

Area	Path
Builtin	ext/standard/class_implements.php / VmClassIntrospection
Enum cases	lib/VM/EnumCaseSupport.php — resolve case object → enum ClassEntry interfaces

Fix together with #5422 if one PR is simpler; keep both acceptance criteria green.

Done when

• class_implements(E::A) returns same array as class_implements(E::class) on VM
• Unit enum cases return UnitEnum only
• test/compliance/cases/stdlib/class_implements_enum_case_object.phpt green
• ./script/ci-fast.sh --filter class_implements_enum green

Related

• Stdlib: class_implements() on enum must return UnitEnum/BackedEnum (ext/standard/basic_functions.c) #5422 — enum type name operand
• Stdlib: is_subclass_of() on enum cases — UnitEnum/BackedEnum must be true (ext/standard/class.c) #5642 — is_subclass_of() on enum cases
• North star: Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492

[PurHur]

claim: worker-lane-c — starting this run

[PurHur]

Merged via #7312.

Changes: resolveClassForClassUses() now resolves enum case operands (TYPE_ENUM_CASE and enum-case objects) to the declaring enum ClassEntry. classImplementsMap() maps implicit unitenum/backedenum keys to UnitEnum/BackedEnum display names (also fixes class_implements(E::class), pairs #5422). JIT uses the same display-name mapping.

Verification:

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/vm.php -r "enum E:int{case A=1;} var_dump(class_implements(E::A));"
vendor/bin/phpunit --filter class_implements_enum
vendor/bin/phpunit --filter ClassImplementsBuiltinTest
'

All green — class_implements(E::A) returns UnitEnum+BackedEnum; compliance + unit tests pass.