pub struct TestTerminal { /* private fields */ }Expand description
A virtual terminal buffer for testing terminal output. Captures all writes, tracks cursor position, and parses ANSI escape sequences including SGR (Select Graphic Rendition) codes for style tracking.
Implements delayed wrapping (DEC-style): when the cursor reaches the last
column, it stays there with a pending-wrap flag. The next printable character
triggers the wrap to column 0 of the next line. A \r clears the flag.
Implementations§
Source§impl TestTerminal
impl TestTerminal
Sourcepub fn resize(&mut self, columns: u16, rows: u16)
pub fn resize(&mut self, columns: u16, rows: u16)
Resize terminal without preserving prior transcript content.
Sourcepub fn resize_preserving_transcript(&mut self, columns: u16, rows: u16)
pub fn resize_preserving_transcript(&mut self, columns: u16, rows: u16)
Resize terminal and reflow existing transcript content to match the new width.
Sourcepub fn get_lines(&self) -> Vec<String>
pub fn get_lines(&self) -> Vec<String>
Get all lines as a vector of strings (trailing whitespace trimmed)
Sourcepub fn get_transcript_lines(&self) -> Vec<String>
pub fn get_transcript_lines(&self) -> Vec<String>
Get full terminal transcript (scrollback history + visible buffer).
Sourcepub fn cursor_position(&self) -> (u16, u16)
pub fn cursor_position(&self) -> (u16, u16)
Get current cursor position as (column, row).
Sourcepub fn get_style_at(&self, row: usize, col: usize) -> Style
pub fn get_style_at(&self, row: usize, col: usize) -> Style
Get the style at a specific buffer position.
Sourcepub fn style_of_text(&self, row: usize, text: &str) -> Option<Style>
pub fn style_of_text(&self, row: usize, text: &str) -> Option<Style>
Find the first occurrence of text on the given row and return its style.
Returns the style of the first character of the matched text.
Sourcepub fn clear_line(&mut self)
pub fn clear_line(&mut self)
Clear the current line
Sourcepub fn move_to_column(&mut self, col: u16)
pub fn move_to_column(&mut self, col: u16)
Move cursor to column (keep same row)
Sourcepub fn move_right(&mut self, n: u16)
pub fn move_right(&mut self, n: u16)
Move cursor right by n positions
Trait Implementations§
Source§impl Clone for TestTerminal
impl Clone for TestTerminal
1.0.0 · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moreSource§impl Debug for TestTerminal
impl Debug for TestTerminal
Source§impl Write for TestTerminal
impl Write for TestTerminal
Source§fn write(&mut self, buf: &[u8]) -> Result<usize>
fn write(&mut self, buf: &[u8]) -> Result<usize>
Source§fn flush(&mut self) -> Result<()>
fn flush(&mut self) -> Result<()>
Source§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
can_vector)1.0.0 · Source§fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>
fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>
Source§fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>
fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>
write_all_vectored)Auto Trait Implementations§
impl Freeze for TestTerminal
impl RefUnwindSafe for TestTerminal
impl Send for TestTerminal
impl Sync for TestTerminal
impl Unpin for TestTerminal
impl UnsafeUnpin for TestTerminal
impl UnwindSafe for TestTerminal
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
Source§impl<T> ExecutableCommand for T
impl<T> ExecutableCommand for T
Source§fn execute(&mut self, command: impl Command) -> Result<&mut T, Error>
fn execute(&mut self, command: impl Command) -> Result<&mut T, Error>
Executes the given command directly.
The given command its ANSI escape code will be written and flushed onto Self.
§Arguments
-
The command that you want to execute directly.
§Example
use std::io;
use crossterm::{ExecutableCommand, style::Print};
fn main() -> io::Result<()> {
// will be executed directly
io::stdout()
.execute(Print("sum:\n".to_string()))?
.execute(Print(format!("1 + 1= {} ", 1 + 1)))?;
Ok(())
// ==== Output ====
// sum:
// 1 + 1 = 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
Source§impl<T> Instrument for T
impl<T> Instrument for T
Source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
Source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moreSource§impl<T> Pointable for T
impl<T> Pointable for T
Source§impl<T> QueueableCommand for T
impl<T> QueueableCommand for T
Source§fn queue(&mut self, command: impl Command) -> Result<&mut T, Error>
fn queue(&mut self, command: impl Command) -> Result<&mut T, Error>
Queues the given command for further execution.
Queued commands will be executed in the following cases:
- When
flushis called manually on the given type implementingio::Write. - The terminal will
flushautomatically if the buffer is full. - Each line is flushed in case of
stdout, because it is line buffered.
§Arguments
-
The command that you want to queue for later execution.
§Examples
use std::io::{self, Write};
use crossterm::{QueueableCommand, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
// `Print` will executed executed when `flush` is called.
stdout
.queue(Print("foo 1\n".to_string()))?
.queue(Print("foo 2".to_string()))?;
// some other code (no execution happening here) ...
// when calling `flush` on `stdout`, all commands will be written to the stdout and therefore executed.
stdout.flush()?;
Ok(())
// ==== Output ====
// foo 1
// foo 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
Source§impl<W> SynchronizedUpdate for W
impl<W> SynchronizedUpdate for W
Source§fn sync_update<T>(
&mut self,
operations: impl FnOnce(&mut W) -> T,
) -> Result<T, Error>
fn sync_update<T>( &mut self, operations: impl FnOnce(&mut W) -> T, ) -> Result<T, Error>
Performs a set of actions within a synchronous update.
Updates will be suspended in the terminal, the function will be executed against self, updates will be resumed, and a flush will be performed.
§Arguments
-
Function
A function that performs the operations that must execute in a synchronized update.
§Examples
use std::io;
use crossterm::{ExecutableCommand, SynchronizedUpdate, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
stdout.sync_update(|stdout| {
stdout.execute(Print("foo 1\n".to_string()))?;
stdout.execute(Print("foo 2".to_string()))?;
// The effects of the print command will not be present in the terminal
// buffer, but not visible in the terminal.
std::io::Result::Ok(())
})?;
// The effects of the commands will be visible.
Ok(())
// ==== Output ====
// foo 1
// foo 2
}§Notes
This command is performed only using ANSI codes, and will do nothing on terminals that do not support ANSI codes, or this specific extension.
When rendering the screen of the terminal, the Emulator usually iterates through each visible grid cell and renders its current state. With applications updating the screen a at higher frequency this can cause tearing.
This mode attempts to mitigate that.
When the synchronization mode is enabled following render calls will keep rendering the last rendered state. The terminal Emulator keeps processing incoming text and sequences. When the synchronized update mode is disabled again the renderer may fetch the latest screen buffer state again, effectively avoiding the tearing effect by unintentionally rendering in the middle a of an application screen update.