[BUG] x_labels(n) add more entries than n.

[SoapyDev]

So I could not find a mention of this, excuse me if it already exist.

Description

Doing a
- LineSeries with the SVGBackend, using NaiveDate as labels on the x-axis.

Expected :

• Limiting the x_labels to 12 should actually limit it to 12.
• Limiting the x_labels to 12 should not create extra labels

Results :

• The graph contains 13 dates.
• The graph created a date that is not existent in the data.
• See the repetition of 2023-03

To reproduce

Code

from & to are NaiveDate made from String going from the first date in the data, to the last.

       let root_area =
            SVGBackend::new(&path, (width, height)).into_drawing_area();
       root_area.fill(&WHITE)?;

    let mut chart = ChartBuilder::on(&root_area)
        .caption(title, ("inter", 30.0).into_font())
        .margin(10)
        .set_label_area_size(LabelAreaPosition::Left, 8.percent())
        .set_label_area_size(LabelAreaPosition::Bottom, 8.percent())
        .set_label_area_size(LabelAreaPosition::Right, 8.percent())
        .build_cartesian_2d(from..to, 0..max)?;

    chart
        .configure_mesh()
        .x_labels(12)
        .y_labels(10)
        .x_label_formatter(&|d| d.format(format).to_string())
        .x_desc("Date")
        .y_desc("Beneficiaires")
        .x_max_light_lines(max_lines)
        .y_max_light_lines(1)
        .draw()?;
    
    for (i, values) in data.iter().enumerate() {
        let color = *colors.get(i % colors.len()).unwrap_or(&BLACK);
        let label = labels.get(i % labels.len());
        let label = label.unwrap().as_str();
        chart
            .draw_series(LineSeries::new(
                values
                    .iter()
                    .map(|(date, x)| (NaiveDate::from_str(date).unwrap(), *x)),
                &color,
            ))?
            .label(label)
            .legend(move |(x, y)| PathElement::new(vec![(x, y), (x + 20, y)], color));
     }

Data

As you can see, I am feeding 5 lines of data, all of them use the same dates.
Only one date exist per month.

[
    [("2023-01-04", 48), ("2023-02-01", 47), ("2023-03-01", 20), ("2023-04-05", 47), ("2023-05-03", 38), 
     ("2023-06-07", 43), ("2023-07-05", 47), ("2023-08-02", 33), ("2023-09-06", 44), ("2023-10-04", 44), 
     ("2023-11-01", 35), ("2023-12-06", 48)],

    [("2023-01-04", 40), ("2023-02-01", 31), ("2023-03-01", 30), ("2023-04-05", 36), ("2023-05-03", 28), 
     ("2023-06-07", 20), ("2023-07-05", 49), ("2023-08-02", 43), ("2023-09-06", 44), ("2023-10-04", 44), 
     ("2023-11-01", 47), ("2023-12-06", 37)],

    [("2023-01-04", 35), ("2023-02-01", 29), ("2023-03-01", 42), ("2023-04-05", 39), ("2023-05-03", 24), 
     ("2023-06-07", 26), ("2023-07-05", 30), ("2023-08-02", 37), ("2023-09-06", 44), ("2023-10-04", 28), 
     ("2023-11-01", 34), ("2023-12-06", 35)],

    [("2023-01-04", 23), ("2023-02-01", 42), ("2023-03-01", 42), ("2023-04-05", 45), ("2023-05-03", 40), 
     ("2023-06-07", 40), ("2023-07-05", 28), ("2023-08-02", 23), ("2023-09-06", 28), ("2023-10-04", 43), 
     ("2023-11-01", 25), ("2023-12-06", 45)],

    [("2023-01-04", 36), ("2023-02-01", 39), ("2023-03-01", 39), ("2023-04-05", 33), ("2023-05-03", 45), 
     ("2023-06-07", 35), ("2023-07-05", 22), ("2023-08-02", 39), ("2023-09-06", 49), ("2023-10-04", 22), 
     ("2023-11-01", 41), ("2023-12-06", 49)]
]

Version information

• Ubuntu 23.04
• Rust 1.74 default
• Plotters 0.3.5 features : datetime