rich/

spinner.rs

//! Spinners.
//!
//! Port of upstream `rich/spinner.py` and the full `rich/_spinners.py` table. A
//! [`Spinner`] picks an animation frame for a point in time;
//! [`Spinner::render`] is the testable surface. Like upstream, the first render
//! fixes the start of the animation, and [`Spinner::update`] can change the
//! text, style or speed mid-animation (a new speed takes effect from the next
//! render, continuing from the current frame). Animation comes from redrawing
//! with a `Live` display, and `ProgressColumn::Spinner` animates one from the
//! progress clock.
//!
//! Scope: all built-in spinners (vendored in `spinner_data.rs`), trailing text
//! as console markup and a frame style. Upstream's non-text trailing
//! renderables (a `Table.grid` of frame and renderable) are not ported.

use std::cell::Cell;

use crate::console::{Console, ConsoleOptions};
use crate::protocol::Renderable;
use crate::segment::Segment;
use crate::style::StyleType;
use crate::text::Text;

/// A named terminal spinner. Mirrors `rich.spinner.Spinner`.
pub struct Spinner {
    frames: &'static [&'static str],
    /// Frame interval in milliseconds.
    interval: f64,
    // Boxed so a spinner stays small inside `ProgressColumn`.
    text: Option<Box<Text>>,
    style: Option<StyleType>,
    speed: Cell<f64>,
    /// Upstream's `start_time`: set by the first render.
    start_time: Cell<Option<f64>>,
    /// Upstream's `frame_no_offset`, carried across a speed change.
    frame_no_offset: Cell<f64>,
    /// Upstream's `_update_speed`: a pending speed (0.0 = none).
    update_speed: Cell<f64>,
}

/// Console markup as upstream's `Text.from_markup(text)`; malformed markup is
/// kept literally rather than failing a spinner.
fn markup(text: &str) -> Text {
    Text::from_markup(text).unwrap_or_else(|_| Text::new(text))
}

impl Spinner {
    /// Look up a built-in spinner by name (falls back to `dots`).
    pub fn new(name: &str) -> Self {
        let (interval, frames) = crate::spinner_data::spinner_data(name)
            .or_else(|| crate::spinner_data::spinner_data("dots"))
            .expect("dots spinner exists");
        Spinner {
            frames,
            interval,
            text: None,
            style: None,
            speed: Cell::new(1.0),
            start_time: Cell::new(None),
            frame_no_offset: Cell::new(0.0),
            update_speed: Cell::new(0.0),
        }
    }

    /// Trailing text after the frame, parsed as console markup (upstream
    /// passes a `str` through `Text.from_markup`).
    pub fn text(mut self, text: impl Into<String>) -> Self {
        self.text = Some(Box::new(markup(&text.into())));
        self
    }

    /// Set the animation speed multiplier (default 1.0).
    pub fn speed(self, speed: f64) -> Self {
        self.speed.set(speed);
        self
    }

    /// Style applied to the spinner *frame* (not the trailing text): a style
    /// or a theme name such as `"status.spinner"`.
    pub fn style(mut self, style: impl Into<StyleType>) -> Self {
        self.style = Some(style.into());
        self
    }

    /// Port of `Spinner.update`: replace the text or style when given, and
    /// schedule a speed change for the next render. Like upstream, empty text
    /// and a zero speed mean "unchanged".
    pub fn update(&mut self, text: Option<&str>, style: Option<StyleType>, speed: Option<f64>) {
        if let Some(text) = text.filter(|t| !t.is_empty()) {
            self.text = Some(Box::new(markup(text)));
        }
        if let Some(style) = style {
            self.style = Some(style);
        }
        if let Some(speed) = speed.filter(|s| *s != 0.0) {
            self.update_speed.set(speed);
        }
    }

    /// Render the spinner as it appears at `time` seconds. Port of
    /// `Spinner.render`: the first call fixes the start time, the frame carries
    /// the spinner style and `Text.assemble(frame, " ", text)` adds the text.
    pub fn render(&self, time: f64) -> Text {
        let start = self.start_time.get().unwrap_or(time);
        self.start_time.set(Some(start));
        let frame_no = (time - start) * self.speed.get() / (self.interval / 1000.0)
            + self.frame_no_offset.get();
        // Python's `int()` truncates toward zero and `%` is non-negative.
        let index = (frame_no.trunc() as i64).rem_euclid(self.frames.len() as i64) as usize;
        let frame_str = self.frames[index];
        let pending = self.update_speed.get();
        if pending != 0.0 {
            self.frame_no_offset.set(frame_no);
            self.start_time.set(Some(time));
            self.speed.set(pending);
            self.update_speed.set(0.0);
        }
        match &self.text {
            // `Text.assemble` turns the frame's style into a span over the
            // frame alone, so the trailing text keeps its own styling.
            Some(text) if !text.plain().is_empty() => {
                let mut assembled = Text::new("");
                assembled.append(frame_str, self.style.clone());
                assembled.append(" ", None);
                assembled.append_text(text)
            }
            _ => {
                let mut frame = Text::new(frame_str);
                if let Some(style) = &self.style {
                    frame.set_base_style(style.clone());
                }
                frame
            }
        }
    }
}

impl Renderable for Spinner {
    fn rich_render(&self, console: &Console, options: &ConsoleOptions) -> Vec<Segment> {
        // A bare print shows the frame at the animation's start; animation
        // needs a Live loop driving `render` with a clock.
        self.render(self.start_time.get().unwrap_or(0.0))
            .rich_render(console, options)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::color::ColorSystem;

    /// The frame at `time` of a spinner whose first render was at 0.
    fn frame_at(name: &str, time: f64) -> String {
        let console = Console::builder()
            .force_terminal(true)
            .color_system(Some(ColorSystem::Truecolor))
            .width(20)
            .build();
        let spinner = Spinner::new(name);
        spinner.render(0.0);
        console.render_to_string(&spinner.render(time))
    }

    #[test]
    fn dots_frames_match_upstream() {
        // Captured from real rich 15.0.0 (start time 0).
        assert_eq!(frame_at("dots", 0.0), "⠋");
        assert_eq!(frame_at("dots", 0.1), "⠙");
        assert_eq!(frame_at("dots", 0.25), "⠸");
    }

    #[test]
    fn line_frames_match_upstream() {
        assert_eq!(frame_at("line", 0.0), "-");
        assert_eq!(frame_at("line", 0.1), "-");
        assert_eq!(frame_at("line", 0.25), "\\");
    }

    #[test]
    fn full_table_covers_more_spinners() {
        // "moon"/"bounce" weren't in the original curated subset. moon: 80ms.
        assert_eq!(frame_at("moon", 0.0), "\u{1f311} ");
        assert_eq!(frame_at("moon", 0.08), "\u{1f312} ");
        assert_eq!(frame_at("bounce", 0.0), "\u{2801}");
    }

    #[test]
    fn arrow_and_dots2_match_upstream() {
        // arrow: interval 100ms → frame advances each 0.1s.
        assert_eq!(frame_at("arrow", 0.0), "←");
        assert_eq!(frame_at("arrow", 0.1), "↖");
        assert_eq!(frame_at("dots2", 0.0), "⣾");
    }

    #[test]
    fn text_follows_frame() {
        let console = Console::builder()
            .force_terminal(true)
            .color_system(Some(ColorSystem::Truecolor))
            .width(20)
            .build();
        let out = console.render_to_string(&Spinner::new("dots").text("Working").render(0.0));
        assert_eq!(out, "⠋ Working");
    }

    #[test]
    fn styled_frame_only() {
        // Captured from real rich 15.0.0: the frame is green, " Working" plain.
        let console = Console::builder()
            .force_terminal(true)
            .color_system(Some(ColorSystem::Truecolor))
            .width(30)
            .no_color(false)
            .build();
        let spinner = Spinner::new("dots")
            .text("Working")
            .style(crate::style::Style::parse("green").unwrap());
        assert_eq!(
            console.render_to_string(&spinner.render(0.0)),
            "\x1b[32m⠋\x1b[0m Working"
        );
    }
}