Close #20839: pkgutil.find_loader now uses importlib.util.find_spec
diff --git a/Lib/pkgutil.py b/Lib/pkgutil.py
index 326657a..58cccdc 100644
--- a/Lib/pkgutil.py
+++ b/Lib/pkgutil.py
@@ -470,29 +470,22 @@
def find_loader(fullname):
"""Find a PEP 302 "loader" object for fullname
- This is s convenience wrapper around :func:`importlib.find_loader` that
- sets the *path* argument correctly when searching for submodules, and
- also ensures parent packages (if any) are imported before searching for
- submodules.
+ This is a backwards compatibility wrapper around
+ importlib.util.find_spec that converts most failures to ImportError
+ and only returns the loader rather than the full spec
"""
if fullname.startswith('.'):
msg = "Relative module name {!r} not supported".format(fullname)
raise ImportError(msg)
- path = None
- pkg_name = fullname.rpartition(".")[0]
- if pkg_name:
- pkg = importlib.import_module(pkg_name)
- path = getattr(pkg, "__path__", None)
- if path is None:
- return None
try:
- return importlib.find_loader(fullname, path)
+ spec = importlib.util.find_spec(fullname)
except (ImportError, AttributeError, TypeError, ValueError) as ex:
# This hack fixes an impedance mismatch between pkgutil and
# importlib, where the latter raises other errors for cases where
# pkgutil previously raised ImportError
msg = "Error while finding loader for {!r} ({}: {})"
raise ImportError(msg.format(fullname, type(ex), ex)) from ex
+ return spec.loader
def extend_path(path, name):
diff --git a/Lib/test/test_pkgutil.py b/Lib/test/test_pkgutil.py
index aaa9d8d..c4410a9 100644
--- a/Lib/test/test_pkgutil.py
+++ b/Lib/test/test_pkgutil.py
@@ -334,6 +334,25 @@
self.assertIsNotNone(pkgutil.get_loader("test.support"))
self.assertEqual(len(w.warnings), 0)
+ def test_get_loader_handles_missing_loader_attribute(self):
+ global __loader__
+ this_loader = __loader__
+ del __loader__
+ try:
+ with check_warnings() as w:
+ self.assertIsNotNone(pkgutil.get_loader(__name__))
+ self.assertEqual(len(w.warnings), 0)
+ finally:
+ __loader__ = this_loader
+
+
+ def test_find_loader_avoids_emulation(self):
+ with check_warnings() as w:
+ self.assertIsNotNone(pkgutil.find_loader("sys"))
+ self.assertIsNotNone(pkgutil.find_loader("os"))
+ self.assertIsNotNone(pkgutil.find_loader("test.support"))
+ self.assertEqual(len(w.warnings), 0)
+
def test_get_importer_avoids_emulation(self):
# We use an illegal path so *none* of the path hooks should fire
with check_warnings() as w: