def test_drop_obs_column():
    adata = ad.AnnData(np.array(X_list), obs=obs_dict, dtype="int32")

    subset = adata[:2]
    assert subset.is_view
    # returns a copy of obs
    assert subset.obs.drop(columns=["oanno1"]).columns.tolist() == ["oanno2", "oanno3"]
    assert subset.is_view
    # would modify obs, so it should actualize subset and not modify adata
    subset.obs.drop(columns=["oanno1"], inplace=True)
    assert not subset.is_view
    assert subset.obs.columns.tolist() == ["oanno2", "oanno3"]

    assert adata.obs.columns.tolist() == ["oanno1", "oanno2", "oanno3"]
def test_bad_urls():
    values = [
        'foo',
        'http://',
        'http://example',
        'http://example.',
        'http://.com',
        'http://invalid-.com',
        'http://-invalid.com',
        'http://inv-.alid-.com',
        'http://inv-.-alid.com',
        'foo bar baz',
        u'foo \u2713',
        'http://@foo:bar@example.com',
        'http://:bar@example.com',
        'http://bar:bar:bar@example.com',
    ]

    for value in values:
        yield check_bad_url_raises, value