Issue #15767: Introduce ModuleNotFoundError, a subclass of
ImportError.
The exception is raised by import when a module could not be found.
Technically this is defined as no viable loader could be found for the
specified module. This includes ``from ... import`` statements so that
the module usage is consistent for all situations where import
couldn't find what was requested.
This should allow for the common idiom of::
try:
import something
except ImportError:
pass
to be updated to using ModuleNotFoundError and not accidentally mask
ImportError messages that should propagate (e.g. issues with a
loader).
This work was driven by the fact that the ``from ... import``
statement needed to be able to tell the difference between an
ImportError that simply couldn't find a module (and thus silence the
exception so that ceval can raise it) and an ImportError that
represented an actual problem.
diff --git a/Include/pyerrors.h b/Include/pyerrors.h
index af37410..2e66c0e 100644
--- a/Include/pyerrors.h
+++ b/Include/pyerrors.h
@@ -152,6 +152,7 @@
PyAPI_DATA(PyObject *) PyExc_FloatingPointError;
PyAPI_DATA(PyObject *) PyExc_OSError;
PyAPI_DATA(PyObject *) PyExc_ImportError;
+PyAPI_DATA(PyObject *) PyExc_ModuleNotFoundError;
PyAPI_DATA(PyObject *) PyExc_IndexError;
PyAPI_DATA(PyObject *) PyExc_KeyError;
PyAPI_DATA(PyObject *) PyExc_KeyboardInterrupt;