Proof of Concept for an issue in Pydantic

When generating the json schema of the model(s), the name of the model is not used in the schema, instead the drive letter is used on Windows machines.

Running

poetry install
poetry run run-poc

Details of the issue

If you run this on a Mac you'll get the expected output like this, where the model name i.e. MyModel is used.

{
  "$defs": {
    "MyModel": {
      "properties": {
        "my_int": {
          "title": "My Int",
          "type": "integer"
        }
      },
      "required": ["my_int"],
      "title": "MyModel",
      "type": "object"
    }
  },
  "title": "My Schema"
}

And if you run it on Windows you will instead get output where MyModel is replaced by the drive letter, like C or D, ... (corresponding to C: or D:, ...) like this:

{
  "$defs": {
    "D": {
      "properties": {
        "my_int": {
          "title": "My Int",
          "type": "integer"
        }
      },
      "required": ["my_int"],
      "title": "MyModel",
      "type": "object"
    }
  },
  "title": "My Schema"
}

Cause

The model is imported using importlib in a fairly untypical way. See the import_my_model function in pydantic_poc/main.py for more details on how it is imported. If you use a relative import instead, the file is not loaded from C: or D: and there's no issue. Same applies if you use the normal python import syntax (import ... from ... or import import ...).

The function get_defs_ref in pydantic/json_schema.py tries to remove an ID by splitting at a colon : character and thus ends up removing everything after the drive letter, so C:\Users\... becomes just C.