1"""OTel-related helpers shared across Plain packages."""
 2
 3from __future__ import annotations
 4
 5
 6def format_exception_type(exc: BaseException) -> str:
 7    """Format an exception's class name per OTel semantic conventions.
 8
 9    Returns the fully-qualified class name (``module.qualname``) for
10    third-party and user-defined exceptions. Python builtins drop the
11    ``builtins.`` prefix so common exceptions stay short.
12
13    Used for the ``error.type`` span attribute, which SHOULD match the
14    ``exception.type`` attribute written by ``span.record_exception()``.
15
16    Examples::
17
18        ValueError                      -> "ValueError"
19        django.db.utils.IntegrityError  -> "django.db.utils.IntegrityError"
20        myapp.errors.BillingError       -> "myapp.errors.BillingError"
21    """
22    cls = type(exc)
23    if cls.__module__ == "builtins":
24        return cls.__qualname__
25    return f"{cls.__module__}.{cls.__qualname__}"