Misleading ShapeError error message

[theidecke]

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• I have checked that this issue has not already been reported.
• I have confirmed this bug exists on the latest version of Polars.

Reproducible example

Log output

No response

Issue description

When trying to create a DataFrame from two series with mismatching length this (rightfully) causes a ShapeError exception, whose error message currently reads something like:

polars.exceptions.ShapeError: could not create a new DataFrame: series 4321 has length 4321 while series "columnname" has length 4320

The issue is, that instead of the name of the first series, the length of the series is returned, but the wording implies that it's the name which is not helpful for debugging the error and can be confusing.

The relevant line in the source code is

polars/crates/polars-core/src/frame/mod.rs

Line 284 in 5f11dd9

columns[0].len(), height, col.name(), col.len()

where the surrounding code currently reads:

        let height = fst.len();
        for col in &columns[1..] {
            polars_ensure!(
                col.len() == height,
                ShapeMismatch: "could not create a new DataFrame: series {:?} has length {} while series {:?} has length {}",
                columns[0].len(), height, col.name(), col.len()
            );
        }

My proposal is that instead it should be:

        let height = fst.len();
        for col in &columns[1..] {
            polars_ensure!(
                col.len() == height,
                ShapeMismatch: "could not create a new DataFrame: series {:?} has length {} while series {:?} has length {}",
                columns[0].name(), height, col.name(), col.len()
            );
        }

Expected behavior

The expected error message should instead read

polars.exceptions.ShapeError: could not create a new DataFrame: series "firstcolumnname" has length 4321 while series "columnname" has length 4320

Installed versions

1.13.1