debugSupportingFiles causes Infinite recursion

Created by: matteomazza91

Description

the option debugSupportingFiles causes a com.fasterxml.jackson.databind.JsonMappingException: Infinite recursion (StackOverflowError) exception.
This only occurs if a Model-schema reference another model-schema

As (part of) the stack trace point out, the CodegenModel has a "parentModel" property that cause the infinite recursion:

[main] INFO org.openapitools.codegen.DefaultGenerator - ############ Supporting file info ############
com.fasterxml.jackson.databind.JsonMappingException: Infinite recursion (StackOverflowError) (through reference chain:      org.openapitools.codegen.CodegenModel["parentModel"]->org.openapitools.codegen.CodegenModel["children"]->java.util.ArrayList[0]->org.openapitools.codegen.CodegenModel["parentModel"]->org.openapitools.codegen.CodegenModel["children"]->java.util.ArrayList[0]->org.openapitools.codegen.CodegenModel["parentModel"]->org.openapitools.codegen.CodegenModel["children"]->java.util.ArrayList[0]->org.openapitools.codegen.CodegenModel["parentModel"]->org.openapitools.codegen.CodegenModel["children"]->java.util.ArrayList[0]->org.openapitools.codegen.CodegenModel["parentModel"]

openapi-generator version

OpenAPI declaration file content or url

This is the OpenAPI that generates the issue: https://pastebin.com/c5tQgWQ9

Note: if the line - $ref: "#/components/schemas/UserDetail" is removed from the User schema, the exception is not raised.

Command line used for generation

java -jar openapi-generator-cli.jar generate -i /path/to/input.yaml -g java -o test/client/petsore/java -DdebugSupportingFiles=true

Steps to reproduce

• create the file /path/to/input.yaml with the content of https://pastebin.com/c5tQgWQ9
• run java -jar openapi-generator-cli.jar generate -i /path/to/input.yaml -g java -o test/client/petsore/java -DdebugSupportingFiles=true

Suggest a fix/enhancement

the call to the debugging method is present in the buildSupportFileBundle method of org.openapitools.codegen.DefaultGenerator class

if (System.getProperty("debugSupportingFiles") != null) {
        LOGGER.info("############ Supporting file info ############");
        Json.prettyPrint(bundle);
 }