API refactor

venv/lib/python3.12/site-packages/structlog/_frames.py

@@ -10,7 +10,9 @@ import traceback
 
 from io import StringIO
 from types import FrameType
+from typing import Callable
 
+from .contextvars import _ASYNC_CALLING_STACK
 from .typing import ExcInfo
 
 
@@ -20,9 +22,6 @@ def _format_exception(exc_info: ExcInfo) -> str:
 
     Shamelessly stolen from stdlib's logging module.
     """
-    if exc_info == (None, None, None):  # type: ignore[comparison-overlap]
-        return "MISSING"
-
     sio = StringIO()
 
     traceback.print_exception(exc_info[0], exc_info[1], exc_info[2], None, sio)
@@ -36,23 +35,27 @@ def _format_exception(exc_info: ExcInfo) -> str:
 
 def _find_first_app_frame_and_name(
     additional_ignores: list[str] | None = None,
+    *,
+    _getframe: Callable[[], FrameType] = sys._getframe,
 ) -> tuple[FrameType, str]:
     """
     Remove all intra-structlog calls and return the relevant app frame.
 
-    Arguments:
-
+    Args:
         additional_ignores:
             Additional names with which the first frame must not start.
 
-    Returns:
+        _getframe:
+            Callable to find current frame. Only for testing to avoid
+            monkeypatching of sys._getframe.
 
+    Returns:
         tuple of (frame, name)
     """
-    ignores = ["structlog"] + (additional_ignores or [])
-    f = sys._getframe()
+    ignores = tuple(["structlog"] + (additional_ignores or []))
+    f = _ASYNC_CALLING_STACK.get(_getframe())
     name = f.f_globals.get("__name__") or "?"
-    while any(tuple(name.startswith(i) for i in ignores)):
+    while name.startswith(ignores):
         if f.f_back is None:
             name = "?"
             break