def test_len(df, pdf):
        df2 = df[["x"]] + 1
        assert len(df2) == len(pdf)
    
        assert len(df[df.x > 5]) == len(pdf[pdf.x > 5])
    
        first = df2.partitions[0].compute()
>       assert len(df2.partitions[0]) == len(first)
E       AssertionError: assert 100 == 10
E        +  where 100 = len(Dask DataFrame Structure:\n                   x\nnpartitions=1       \n0              int64\n10               ...\nDask Name: partitions, 4 expressions\nExpr=Partitions(frame=df[['x']] + 1, partitions=[0]))
E        +  and   10 = len(    x\n0   1\n1   2\n2   3\n3   4\n4   5\n5   6\n6   7\n7   8\n8   9\n9  10)

dask/dataframe/dask_expr/tests/test_collection.py:1718: AssertionError

FAILED dask/dataframe/dask_expr/tests/test_collection.py::test_len - AssertionError: assert 100 == 10
 +  where 100 = len(Dask DataFrame Structure:\n                   x\nnpartitions=1       \n0              int64\n10               ...\nDask Name: partitions, 4 expressions\nExpr=Partitions(frame=df[['x']] + 1, partitions=[0]))
 +  and   10 = len(    x\n0   1\n1   2\n2   3\n3   4\n4   5\n5   6\n6   7\n7   8\n8   9\n9  10)