def test_layers_view():
    X = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
    L = np.array([[10, 11, 12], [13, 14, 15], [16, 17, 18]])
    real_adata = ad.AnnData(X)
    real_adata.layers["L"] = L
    view_adata = real_adata[1:, 1:]
    real_hash = joblib.hash(real_adata)
    view_hash = joblib.hash(view_adata)

    assert view_adata.is_view

    with pytest.raises(ValueError):
        view_adata.layers["L2"] = L + 2

    assert view_adata.is_view  # Failing to set layer item makes adata not view
    assert real_hash == joblib.hash(real_adata)
    assert view_hash == joblib.hash(view_adata)

    view_adata.layers["L2"] = L[1:, 1:] + 2

    assert not view_adata.is_view
    assert real_hash == joblib.hash(real_adata)
    assert view_hash != joblib.hash(view_adata)
def visitdir(self, path):
        """Similar to matcher.visitdir"""
        path = normalizerootdir(path, "visitdir")
        if self.matchrecursive:
            return "all"
        elif self.unsurerecursive:
            return True
        elif path == "":
            return True

        if self._kindpats and self._compiledpats(path):
            # XXX: This is incorrect. But re patterns are already used in
            # production. We should kill them!
            # Need to test "if every string starting with 'path' matches".
            # Obviously it's impossible to test *every* string with the
            # standard regex API, therefore pick a random strange path to test
            # it approximately.
            if self._compiledpats("%s/*/_/-/0/*" % path):
                return "all"
            else:
                return True

        if self._globdirpats and self._compileddirpats(path):
            return True

        subdir, rest = self._split(path)
        subtree = self.get(subdir)
        if subtree is None:
            return False
        else:
            return subtree.visitdir(rest)