tui/testing/
helpers.rs

1use std::fmt::Write;
2
3use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
4
5use crate::Line;
6use crate::Style;
7use crate::display_width_text;
8use crate::rendering::frame::Cursor;
9use crate::rendering::frame::Frame;
10use crate::rendering::renderer::Renderer;
11use crate::{SelectOption, ViewContext};
12
13use super::TestTerminal;
14
15fn frame_from_lines(lines: &[crate::line::Line], _width: u16, _rows: u16) -> Frame {
16    Frame::new(lines.to_vec())
17        .with_cursor(Cursor { row: lines.len().saturating_sub(1), col: 0, is_visible: true })
18        .clamp_cursor()
19}
20
21pub fn render_component(mut render: impl FnMut(&ViewContext) -> Frame, width: u16, rows: u16) -> TestTerminal {
22    let ctx = ViewContext::new((width, rows));
23    let frame = render(&ctx);
24    let terminal = TestTerminal::new(width, rows);
25    let mut renderer = Renderer::new(terminal, crate::theme::Theme::default(), (width, rows));
26    renderer.render_frame(|_| frame).unwrap();
27    renderer.writer().clone()
28}
29
30pub fn render_component_with_renderer(
31    mut render: impl FnMut(&ViewContext) -> Frame,
32    renderer: &mut Renderer<TestTerminal>,
33    width: u16,
34    rows: u16,
35) {
36    let ctx = ViewContext::new((width, rows));
37    let frame = render(&ctx);
38    renderer.render_frame(|_| frame).unwrap();
39}
40
41pub fn render_lines(lines: &[crate::line::Line], width: u16, rows: u16) -> TestTerminal {
42    render_component(|_| frame_from_lines(lines, width, rows), width, rows)
43}
44
45pub fn key(code: KeyCode) -> KeyEvent {
46    KeyEvent::new(code, KeyModifiers::NONE)
47}
48
49pub fn pad(text: &str, width: usize) -> String {
50    format!("{text:<width$}")
51}
52
53pub fn cols(parts: &[(&str, usize)]) -> String {
54    let mut out = String::new();
55    for (text, width) in parts {
56        let _ = write!(out, "{text:<width$}");
57    }
58    out.trim_end().to_string()
59}
60
61pub fn sample_options() -> Vec<SelectOption> {
62    vec![
63        SelectOption { value: "a".into(), title: "Alpha".into(), description: None },
64        SelectOption { value: "b".into(), title: "Beta".into(), description: None },
65        SelectOption { value: "c".into(), title: "Gamma".into(), description: None },
66    ]
67}
68
69/// Returns the style of the span that covers the given display column.
70/// Useful in tests for asserting background/foreground colors at a position.
71pub fn style_at_column(line: &Line, col: usize) -> Style {
72    let mut current = 0;
73    for span in line.spans() {
74        let width = display_width_text(span.text());
75        if col < current + width {
76            return span.style();
77        }
78        current += width;
79    }
80    Style::default()
81}
tui/testing/helpers.rs

tui/testing/
helpers.rs
