refactor: centralize common schema checks in ModelUtils

[Mattias-Sehlstedt]

Adds a SchemaUtils class with common schema operations. Improves readability and makes the if-cases easier to read as the method name clearly highlights what is checked.

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Summary by cubic

Centralizes schema checks in ModelUtils and refactors generators/utilities to use them for consistent, clearer logic. No functional changes intended.

• Refactors
  • Added helpers in org.openapitools.codegen.utils.ModelUtils: hasAllOf, hasOneOf, hasAnyOf, hasProperties, hasEnum, isObjectTypeOAS30.
  • Replaced inline checks across DefaultCodegen, InlineModelResolver, OpenAPINormalizer, language codegens (AbstractJavaCodegen, AbstractPhpCodegen, AbstractPythonCodegen, AbstractPythonPydanticV1Codegen, CppHttplibServerCodegen, CppRestSdkClientCodegen), and OpenApiSchemaValidations.
  • C++ server: added local isNestedObject and standardized oneOf/anyOf handling using std::variant.

^{Written for commit 79df5f5. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 12 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java:1113">
P1: Complex composed schemas can skip property normalization because this condition checks `hasEnum` instead of `hasProperties`.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[wing328]

thanks for the PR for refactoring the code.

what about putting these functions in ModelUtils instead as some functions in ModelUtils already doing something similar?

[Mattias-Sehlstedt]

@wing328 Good suggestion, had missed that they do basically the same. I have instead moved everything into ModelUtils and utilized it in relevant places.