Handle enum string properties in test data generation

Updates Dart test template to use the first enum value for string properties with enums when generating test data, instead of always using the example value. This ensures generated test data is valid for properties with restricted enum values.

Author: Fellmonkey

templates/dart/test/services/service_test.dart.twig

@@ -1,6 +1,6 @@
 {% macro sub_schema(definitions, property) %}{% if property.sub_schema %}{% if property.type == 'array' %}List<<String, dynamic>>{% else %}<String, dynamic>{
   {% if definitions[property.sub_schema] %}{% for property in definitions[property.sub_schema].properties | filter(p => p.required) %}
-  '{{property.name | escapeDollarSign}}': {% if property.type == 'object' %}{% if property.sub_schema and (property.sub_schema != 'prefs' and property.sub_schema != 'preferences') %}{{_self.sub_schema(spec.definitions, property)}}{% else %}<String, dynamic>{}{% endif %}{% elseif property.type == 'array' %}[]{% elseif property.type == 'string' %}'{{property.example | escapeDollarSign}}'{% elseif property.type == 'boolean' %}true{% else %}{{property.example}}{% endif %},
+  '{{property.name | escapeDollarSign}}': {% if property.type == 'object' %}{% if property.sub_schema and (property.sub_schema != 'prefs' and property.sub_schema != 'preferences') %}{{_self.sub_schema(spec.definitions, property)}}{% else %}<String, dynamic>{}{% endif %}{% elseif property.type == 'array' %}[]{% elseif property.type == 'string' %}{% if property.enum %}'{{property.enum[0]}}'{% else %}'{{property.example | escapeDollarSign}}'{% endif %}{% elseif property.type == 'boolean' %}true{% else %}{{property.example}}{% endif %},
   {% endfor %}{% endif %}}{% endif %}{% else %}{% if property.type == 'object' and property.additionalProperties %}Map<String, dynamic>{% else %}{{property | typeName}}{% endif %}{% endif %}{% endmacro %}
 {% import 'flutter/base/utils.twig' as utils %}
 {% if 'dart' in language.params.packageName %}
@@ -69,7 +69,7 @@ void main() {
                 {%~ if method.responseModel and method.responseModel != 'any' ~%}
             final Map<String, dynamic> data = {
                 {%- for definition in spec.definitions ~%}{%~ if definition.name == method.responseModel -%}{%~ for property in definition.properties | filter((param) => param.required) ~%}
-                '{{property.name | escapeDollarSign}}': {% if property.type == 'object' %}{% if property.sub_schema and (property.sub_schema != 'prefs' and property.sub_schema != 'preferences') %}{{_self.sub_schema(spec.definitions, property)}}{% else %}<String, dynamic>{}{% endif %}{% elseif property.type == 'array' %}[]{% elseif property.type == 'string' %}'{{property.example | escapeDollarSign}}'{% elseif property.type == 'boolean' %}true{% else %}{{property.example}}{% endif %},{%~ endfor ~%}{% set break = true %}{%- else -%}{% set continue = true %}{%- endif -%}{%~ endfor -%}
+                '{{property.name | escapeDollarSign}}': {% if property.type == 'object' %}{% if property.sub_schema and (property.sub_schema != 'prefs' and property.sub_schema != 'preferences') %}{{_self.sub_schema(spec.definitions, property)}}{% else %}<String, dynamic>{}{% endif %}{% elseif property.type == 'array' %}[]{% elseif property.type == 'string' %}{% if property.enum %}'{{property.enum[0]}}'{% else %}'{{property.example | escapeDollarSign}}'{% endif %}{% elseif property.type == 'boolean' %}true{% else %}{{property.example}}{% endif %},{%~ endfor ~%}{% set break = true %}{%- else -%}{% set continue = true %}{%- endif -%}{%~ endfor -%}
 
             };
                 {%~ else ~%}