Generation fails with IndexError: tuple out of range

[SimonDeBroyer]

Describe the bug

Generating fails with error IndexError: tuple index out of range

To Reproduce

Example schema:

components:
    schemas:
        Collection-Wrapper:
            description: Generic response wrapper containing a collection of items and pagination metadata.
            type: object
            required:
                - data
                - pagination
            properties:
                data:
                    description: Array of items in the collection.
                    type: array
                    items:
                        type: object
                pagination:
                    description: Pagination metadata for the collection.
                    $ref: "#/components/schemas/Metadata"
        DataType:
            type: object
            required:
                - id
            properties:
                property_1:
                    type: string
                    format: uuid
                    readOnly: true
                    description: Unique identifier for the installation.
                property_2:
                    type: string
                    description: Description of the installation.
                property_3:
                    type: string
                    format: date-time
                    readOnly: true
                    description: Timestamp when the installation was created.

        PaginatedDataTypeList:
            allOf:
                - properties:
                      data:
                          type: array
                          items:
                              $ref: "#/components/schemas/DataType"
                - $ref: "#/components/schemas/Collection-Wrapper"
        Metadata:
            type: object
            required:
                - limit
                - page
            properties:
                limit:
                    type: integer
                    minimum: 1
                    maximum: 100
                    description: Number of data types returned in this response
                    example: 20
                page:
                    type: integer
                    minimum: 1
                    description: The page number to retrieve
                    example: 2

Used commandline:

$ datamodel-codegen

used pyproject.toml configuration

[tool.datamodel-codegen]
input = "openapi.yaml"
output = "src/views/models.py"
output-model-type = "pydantic_v2.BaseModel"
input-file-type = "openapi"
formatters = ["ruff-check", "ruff-format"]
reuse-model = true
reuse-scope = "tree"

Expected behavior
If the combination of config options is not allowed, I expected to get a warning/error message, otherwise I expected generation to work.

Version:

• OS: Windows 11 Pro
• Python version: 3.13.11
• datamodel-code-generator version: 0.52.2

Additional context

Full error traceback

Traceback (most recent call last):
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\__main__.py", line 1363, in main
    run_generate_from_config(
    ~~~~~~~~~~~~~~~~~~~~~~~~^
        config=config,
        ^^^^^^^^^^^^^^
    ...<8 lines>...
        default_value_overrides=default_value_overrides,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\__main__.py", line 938, in run_generate_from_config
    result = generate(
        input_=input_,
    ...<125 lines>...
        default_value_overrides=default_value_overrides,
    )
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\__init__.py", line 764, in generate
    results = parser.parse(
        settings_path=config.settings_path,
    ...<3 lines>...
        module_split_mode=config.module_split_mode,
    )
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\parser\base.py", line 3172, in parse
    ) = self._build_module_structure(sorted_data_models, require_update_action_models, module_split_mode)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\parser\base.py", line 2920, in _build_module_structure
    shared_module_entry = self.__reuse_model_tree_scope(module_models, require_update_action_models)
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\parser\base.py", line 1751, in __reuse_model_tree_scope
    self.__validate_shared_module_name(module_models)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^
  File "C:\Users\SimonDeBroyer\Documents\Projects\platform\.venv\Lib\site-packages\datamodel_code_generator\parser\base.py", line 1658, in __validate_shared_module_name
    existing_module_names = {module[0] for module, _ in module_models}
                             ~~~~~~^^^
IndexError: tuple index out of range

[github-actions]

🎉 Released in 0.53.0

The fix/feature from PR #2954 has been included in this release. See the release notes for details.

Thank you for your contribution!