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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"test_bdb is sensitive to sys.meta_path manipulation","articleBody":"Here's a repro not involving Setuptools showing how `test_bdb` is sensitive to `sys.meta_path` manipulation:\r\n\r\n```\r\nFROM jaraco/multipy-tox\r\n\r\nRUN apt install -y libarchive-tools\r\nRUN apt install -y build-essential gdb lcov pkg-config libbz2-dev libffi-dev libgdbm-dev libgdbm-compat-dev liblzma-dev libncurses5-dev libreadline6-dev libsqlite3-dev libssl-dev lzma lzma-dev tk-dev uuid-dev zlib1g-dev\r\nRUN wget -O - https://github.com/python/cpython/archive/refs/heads/3.9.zip | bsdtar -xf -\r\nWORKDIR cpython-3.9\r\nRUN sh ./configure --prefix /opt/python\r\nRUN make install\r\nWORKDIR /\r\nRUN /opt/python/bin/python3 -m pip install --upgrade pip\r\nRUN /opt/python/bin/python3 -m pip uninstall -y setuptools\r\nRUN echo \"import sys; sys.meta_path.insert(0, type('NullFinder', (), dict(find_spec=lambda *args: None))())\" \u003e /opt/python/lib/python3.9/site-packages/null-finder.pth\r\nCMD /opt/python/bin/python3 -m test_bdb\r\n```\r\n\r\nIt fails with a similar error:\r\n\r\n```\r\nAssertionError: Wrong event type at expect_set item 2, got 'call'\r\n  Expected: ('line', 3, 'tfunc_import')\r\n  Got:      ('call', 1, '\u003clambda\u003e'),        ('quit',),\r\n```\r\n\r\n_Originally posted by @jaraco in https://github.com/python/cpython/issues/91169#issuecomment-1158978878_","author":{"url":"https://github.com/jaraco","@type":"Person","name":"jaraco"},"datePublished":"2022-06-17T15:22:38.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/93951/cpython/issues/93951"}