ggplot-rs 0.21.1

//! Fixed-domain gradient/colour-continuous scales (anofox-visualization
//! PR #324): `with_limits(lo, hi)` on `ScaleColorContinuous`,
//! `ScaleColorGradient2` and `ScaleColorGradientN` fixes the *colour*
//! domain (not just the legend) to `[lo, hi]`, with ggplot2's out-of-bounds
//! semantics: `Oob::Censor` (default) renders an out-of-range value in the
//! scale's `na_value` (ggplot2's own `na.value`, default grey — review
//! PR#141 finding 3, not a bare `None` the geom silently papers over with
//! its own unrelated default colour), `Oob::Squish` (opt-in via
//! `with_oob`) clamps it to the nearest limit instead. The same `na_value`
//! is used for a genuinely missing (`NA`) or non-finite value.

use ggplot_rs::aes::Aesthetic;
use ggplot_rs::prelude::*;
use ggplot_rs::scale::Scale;

fn c(v: f64) -> Value {
    Value::Float(v)
}

#[test]
fn without_limits_the_domain_still_trains_from_data() {
    let mut s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0));
    s.train(&[c(-5.0), c(5.0)]);
    assert_eq!(s.domain(), Some((-5.0, 5.0)));
    assert_eq!(s.map_to_color(&c(-5.0)), Some((0, 0, 255)));
    assert_eq!(s.map_to_color(&c(5.0)), Some((255, 0, 0)));
}

#[test]
fn with_limits_the_domain_is_fixed_and_training_does_not_widen_it() {
    let mut s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(-1.0, 1.0);
    // Data far outside [-1, 1] must not widen the fixed domain.
    s.train(&[c(-100.0), c(100.0)]);
    assert_eq!(s.domain(), Some((-1.0, 1.0)));
    // The *colours* reflect the fixed domain too, not just the legend.
    assert_eq!(s.map_to_color(&c(-1.0)), Some((0, 0, 255)));
    assert_eq!(s.map_to_color(&c(0.0)), Some((127, 0, 127)));
    assert_eq!(s.map_to_color(&c(1.0)), Some((255, 0, 0)));
}

#[test]
fn oob_censor_is_the_default_and_uses_na_value_for_out_of_range_colours() {
    let s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(-1.0, 1.0);
    assert_eq!(s.map_to_color(&c(0.5)), Some((191, 0, 63)));
    assert_eq!(
        s.map_to_color(&c(1.5)),
        Some((127, 127, 127)),
        "oob: ggplot2's grey na_value by default, not a plausible colour"
    );
    assert_eq!(s.map_to_color(&c(-1.5)), Some((127, 127, 127)));
}

#[test]
fn na_value_is_also_used_for_a_genuinely_missing_or_non_finite_value() {
    let s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0));
    assert_eq!(s.map_to_color(&Value::Na), Some((127, 127, 127)));
    assert_eq!(s.map_to_color(&c(f64::NAN)), Some((127, 127, 127)));
    assert_eq!(s.map_to_color(&c(f64::INFINITY)), Some((127, 127, 127)));
}

#[test]
fn with_na_value_overrides_the_default_grey() {
    let s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(-1.0, 1.0)
        .with_na_value((9, 9, 9));
    assert_eq!(s.map_to_color(&c(5.0)), Some((9, 9, 9)));
    assert_eq!(s.map_to_color(&Value::Na), Some((9, 9, 9)));
}

#[test]
fn oob_squish_clamps_to_the_nearest_limit() {
    let s = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(-1.0, 1.0)
        .with_oob(Oob::Squish);
    assert_eq!(s.map_to_color(&c(1.5)), Some((255, 0, 0)), "squished to hi");
    assert_eq!(
        s.map_to_color(&c(-1.5)),
        Some((0, 0, 255)),
        "squished to lo"
    );
    assert_eq!(s.map_to_color(&c(50.0)), s.map_to_color(&c(1.0)));
}

#[test]
fn gradient2_respects_limits_and_oob_around_the_midpoint() {
    let s = ScaleColorGradient2::new(Aesthetic::Fill)
        .with_colors(
            RGBAColor::new(0, 0, 255),
            RGBAColor::new(255, 255, 255),
            RGBAColor::new(255, 0, 0),
        )
        .with_midpoint(0.0)
        .with_limits(-1.0, 1.0);
    assert_eq!(s.map_to_color(&c(0.0)), Some((255, 255, 255)));
    assert_eq!(s.map_to_color(&c(-1.0)), Some((0, 0, 255)));
    assert_eq!(s.map_to_color(&c(1.0)), Some((255, 0, 0)));
    assert_eq!(
        s.map_to_color(&c(2.0)),
        Some((127, 127, 127)),
        "censored by default (na_value)"
    );

    let squished = s.with_oob(Oob::Squish);
    assert_eq!(squished.map_to_color(&c(2.0)), Some((255, 0, 0)));
    assert_eq!(squished.map_to_color(&c(-2.0)), Some((0, 0, 255)));
}

#[test]
fn gradientn_respects_limits_and_oob() {
    let stops = vec![
        (0.0, RGBAColor::new(0, 0, 255)),
        (0.5, RGBAColor::new(255, 255, 255)),
        (1.0, RGBAColor::new(255, 0, 0)),
    ];
    let s = ScaleColorGradientN::new(Aesthetic::Fill, stops).with_limits(0.0, 10.0);
    assert_eq!(s.map_to_color(&c(0.0)), Some((0, 0, 255)));
    assert_eq!(s.map_to_color(&c(10.0)), Some((255, 0, 0)));
    assert_eq!(
        s.map_to_color(&c(20.0)),
        Some((127, 127, 127)),
        "censored by default (na_value)"
    );

    let squished = s.with_oob(Oob::Squish);
    assert_eq!(squished.map_to_color(&c(20.0)), Some((255, 0, 0)));
    assert_eq!(squished.map_to_color(&c(-20.0)), Some((0, 0, 255)));
}

#[test]
fn a_fixed_domain_tile_plot_colours_a_correlation_matrix_correctly() {
    use ggplot_rs::data::Value;
    let data: Vec<(String, Vec<Value>)> = vec![
        (
            "x".into(),
            vec![Value::Str("a".into()), Value::Str("b".into())],
        ),
        (
            "y".into(),
            vec![Value::Str("a".into()), Value::Str("a".into())],
        ),
        ("v".into(), vec![c(1.0), c(-1.0)]),
    ];
    let svg = GGPlot::new(data)
        .aes(Aes::new().x("x").y("y").fill("v"))
        .geom_tile()
        .scale_fill(
            ScaleColorContinuous::new(Aesthetic::Fill)
                .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
                .with_limits(-1.0, 1.0),
        )
        .render_svg_native_with_size(300, 200)
        .unwrap();
    assert!(svg.contains("fill=\"#FF0000\""), "{svg}");
    assert!(svg.contains("fill=\"#0000FF\""), "{svg}");
}

#[test]
fn inverted_limits_do_not_panic_and_censor_everything() {
    // Review PR#141 finding 6 (LOW), plus a defensive fix: lo > hi has no
    // valid in-bounds region at all, so every value is treated as
    // censored regardless of Oob — including under Squish, which would
    // otherwise hit f64::clamp's "min > max" panic.
    let squish = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(5.0, 1.0)
        .with_oob(Oob::Squish);
    assert_eq!(squish.map_to_color(&c(3.0)), Some((127, 127, 127)));

    let censor = ScaleColorContinuous::new(Aesthetic::Fill)
        .with_colors(RGBAColor::new(0, 0, 255), RGBAColor::new(255, 0, 0))
        .with_limits(5.0, 1.0);
    assert_eq!(censor.map_to_color(&c(3.0)), Some((127, 127, 127)));
}

#[test]
fn inverted_limits_warn_on_all_three_gradient_scales() {
    let data = frame(vec![
        ("x", floats(&[1.0])),
        ("y", floats(&[1.0])),
        ("v", floats(&[1.0])),
    ]);

    let (_, warnings) = GGPlot::new(data.clone())
        .aes(Aes::new().x("x").y("y").fill("v"))
        .geom_point()
        .scale_fill(ScaleColorContinuous::new(Aesthetic::Fill).with_limits(5.0, 1.0))
        .render_svg_native_with_warnings(300, 200)
        .unwrap();
    assert!(
        warnings.iter().any(|w| w.contains("lo > hi")),
        "ScaleColorContinuous: {warnings:?}"
    );

    let (_, warnings) = GGPlot::new(data.clone())
        .aes(Aes::new().x("x").y("y").fill("v"))
        .geom_point()
        .scale_fill(ScaleColorGradient2::new(Aesthetic::Fill).with_limits(5.0, 1.0))
        .render_svg_native_with_warnings(300, 200)
        .unwrap();
    assert!(
        warnings.iter().any(|w| w.contains("lo > hi")),
        "ScaleColorGradient2: {warnings:?}"
    );

    let (_, warnings) = GGPlot::new(data)
        .aes(Aes::new().x("x").y("y").fill("v"))
        .geom_point()
        .scale_fill(
            ScaleColorGradientN::new(Aesthetic::Fill, vec![(0.0, RGBAColor::new(0, 0, 0))])
                .with_limits(5.0, 1.0),
        )
        .render_svg_native_with_warnings(300, 200)
        .unwrap();
    assert!(
        warnings.iter().any(|w| w.contains("lo > hi")),
        "ScaleColorGradientN: {warnings:?}"
    );
}

fn frame(cols: Vec<(&str, Vec<Value>)>) -> Vec<(String, Vec<Value>)> {
    cols.into_iter().map(|(k, v)| (k.to_string(), v)).collect()
}
fn floats(v: &[f64]) -> Vec<Value> {
    v.iter().map(|&f| Value::Float(f)).collect()
}