Struct TestBackend 

pub struct TestBackend { /* private fields */ }

Implementations

impl TestBackend

pub fn new(width: u32, height: u32) -> Self

pub fn render(&mut self, f: impl FnOnce(&mut Context))

Run a closure as if it were one frame, render to internal buffer

pub fn render_with_events( &mut self, events: Vec<Event>, focus_index: usize, prev_focus_count: usize, f: impl FnOnce(&mut Context), )

Render with specific events (for testing keyboard/mouse interaction)

pub fn run_with_events( &mut self, events: Vec<Event>, f: impl FnOnce(&mut Context), )

pub fn line(&self, y: u32) -> String

Get the rendered text content of row y (trimmed trailing spaces)

pub fn assert_line(&self, y: u32, expected: &str)

Assert that row y contains expected as a substring

pub fn assert_line_contains(&self, y: u32, expected: &str)

Assert that row y contains expected as a substring

pub fn assert_contains(&self, expected: &str)

Assert that any line in the buffer contains expected

pub fn buffer(&self) -> &Buffer

pub fn width(&self) -> u32

pub fn height(&self) -> u32

pub fn to_string_trimmed(&self) -> String

Return the full rendered buffer as a multi-line string.

Each row is trimmed of trailing spaces and joined with newlines. Useful for snapshot testing with insta::assert_snapshot!.

Trait Implementations

impl Display for TestBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.