diff --git a/changelog/7671.trivial.rst b/changelog/7671.trivial.rst new file mode 100644 index 00000000000..6dddf4cf042 --- /dev/null +++ b/changelog/7671.trivial.rst @@ -0,0 +1,6 @@ +When collecting tests, pytest finds test classes and functions by examining the +attributes of python objects (modules, classes and instances). To speed up this +process, pytest now ignores builtin attributes (like ``__class__``, +``__delattr__`` and ``__new__``) without consulting the ``python_classes`` and +``python_functions`` configuration options and without passing them to plugins +using the ``pytest_pycollect_makeitem`` hook. diff --git a/src/_pytest/python.py b/src/_pytest/python.py index 21aa8457611..be21b61d61e 100644 --- a/src/_pytest/python.py +++ b/src/_pytest/python.py @@ -5,6 +5,7 @@ import itertools import os import sys +import types import typing import warnings from collections import Counter @@ -343,6 +344,26 @@ def reportinfo(self) -> Tuple[Union[py.path.local, str], int, str]: return fspath, lineno, modpath +# As an optimization, these builtin attribute names are pre-ignored when +# iterating over an object during collection -- the pytest_pycollect_makeitem +# hook is not called for them. +# fmt: off +class _EmptyClass: pass # noqa: E701 +IGNORED_ATTRIBUTES = frozenset.union( # noqa: E305 + frozenset(), + # Module. + dir(types.ModuleType("empty_module")), + # Some extra module attributes the above doesn't catch. + {"__builtins__", "__file__", "__cached__"}, + # Class. + dir(_EmptyClass), + # Instance. + dir(_EmptyClass()), +) +del _EmptyClass +# fmt: on + + class PyCollector(PyobjMixin, nodes.Collector): def funcnamefilter(self, name: str) -> bool: return self._matches_prefix_or_glob_option("python_functions", name) @@ -404,6 +425,8 @@ def collect(self) -> Iterable[Union[nodes.Item, nodes.Collector]]: # Note: seems like the dict can change during iteration - # be careful not to remove the list() without consideration. for name, obj in list(dic.items()): + if name in IGNORED_ATTRIBUTES: + continue if name in seen: continue seen.add(name) diff --git a/testing/python/collect.py b/testing/python/collect.py index 778ceeddf8d..ab4a6fbb832 100644 --- a/testing/python/collect.py +++ b/testing/python/collect.py @@ -885,6 +885,34 @@ def test_something(): result = testdir.runpytest_subprocess() result.stdout.fnmatch_lines(["*1 passed*"]) + def test_early_ignored_attributes(self, testdir: Testdir) -> None: + """Builtin attributes should be ignored early on, even if + configuration would otherwise allow them. + + This tests a performance optimization, not correctness, really, + although it tests PytestCollectionWarning is not raised, while + it would have been raised otherwise. + """ + testdir.makeini( + """ + [pytest] + python_classes=* + python_functions=* + """ + ) + testdir.makepyfile( + """ + class TestEmpty: + pass + test_empty = TestEmpty() + def test_real(): + pass + """ + ) + items, rec = testdir.inline_genitems() + assert rec.ret == 0 + assert len(items) == 1 + def test_setup_only_available_in_subdir(testdir): sub1 = testdir.mkpydir("sub1")