[PHP][php-symfony] Fix native enum default value expression in AbstractPhpCodegen

[JerrySLau]

Summary

AbstractPhpCodegen.toEnumDefaultValue historically returned self::{datatype}_{case}, which matches old class-constant style enums (#10273) but is invalid for PHP 8.1 backed enums when datatype is a namespaced class name. After #23541, OpenAPI default beside an enum $ref on model properties flows through updateCodegenPropertyEnum, so the wrong expression is emitted into model_variables.mustache (#16605) and breaks php -l / static analysis.

This change emits {datatype}::{case} (native enum case reference), documents the data flow in Javadoc, extends the existing php-symfony fixture optional-enum-query-ref-default.yaml with a pet-store POST /pets + Pet.HTTP.CreatePetRequest example, and adds PhpSymfonyServerCodegenTest#testModelPropertyEnumRefWithDefaultUsesNativeEnumCaseInCodegen to lock the behavior.

Branch vs master (this workspace): 1 commit touching AbstractPhpCodegen.java, PhpSymfonyServerCodegenTest.java, optional-enum-query-ref-default.yaml.

How to validate

1. Unit / generator tests:
   ./mvnw -pl modules/openapi-generator '-Dtest=org.openapitools.codegen.php.**' test
2. Manual / CLI: Generate php-symfony from modules/openapi-generator/src/test/resources/3_1/php-symfony/optional-enum-query-ref-default.yaml and confirm PetHTTPCreatePetRequest (or equivalent) uses …::AVAILABLE (or FQCN ::CASE) for the defaulted enum property, not self::…_AVAILABLE.
3. Regression: Existing testOptionalEnumRefQueryParameterWithDefaultAppliesOpenApiSemantics on the same YAML still passes (optional enum query + default).

Related

• Root cause and options: internal analysis fix_php_enum_ref_default_backed_enum.md.
• Related upstream history: fix(php): honor OpenAPI default beside $ref in toDefaultValue #23541 (toDefaultValue + $ref + default), Fix php enum default value initialization #10273 (toEnumDefaultValue shape), [php-symfony] Support for default scalar value of properties in model #16605 (php-symfony property initializer uses defaultValue).
• If a GitHub issue is filed for this bug, add fixes #NNNN here.

cc PHP committee: @jebentier @dkarlovi @mandrean @jfastnacht @ybelenko @renepardon
cc PHP Symfony: @ksm2 @BenjaminHae

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Summary by cubic

Fixes generation of PHP 8.1 backed-enum defaults in php-symfony. We now emit Type::CASE (using the short class name under modelPackage) instead of self::FQCN_CASE, so enum defaults on $ref-backed model properties compile and lint correctly.

• Bug Fixes
  • Update AbstractPhpCodegen.toEnumDefaultValue to return {datatype}::{case} for native enums and strip modelPackage so model defaults use the short class name.
  • Add Javadoc explaining enum default flow via updateCodegenPropertyEnum.
  • Extend optional-enum-query-ref-default.yaml with Pet.HTTP.CreatePetRequest using an enum $ref + default.
  • Add regression test PhpSymfonyServerCodegenTest#testModelPropertyEnumRefWithDefaultUsesNativeEnumCaseInCodegen.

^{Written for commit 6fbc3b7. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 3 files