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/Lib/test/test_pydoc.py b/Lib/test/test_pydoc.py
index 399f818..95ef115 100644
--- a/Lib/test/test_pydoc.py
+++ b/Lib/test/test_pydoc.py
@@ -206,7 +206,7 @@
missing_pattern = "no Python documentation found for '%s'"
# output pattern for module with bad imports
-badimport_pattern = "problem in %s - ImportError: No module named %r"
+badimport_pattern = "problem in %s - ModuleNotFoundError: No module named %r"
def run_pydoc(module_name, *args, **env):
"""