Unnamed repository; edit this file 'description' to name the repository.
tui: Cache the keyboard enhancement check
Wether the host terminal supports keyboard enhancement can be cached
for the lifetime of a Helix session.
Caching this lookup prevents a potential lockup within crossterm's
event reading system where the query for the keyboard enhancement
support waits on the next keyboard event, which can happen if the
crossterm event stream is checked by `tokio::select!` in another
thread.
| -rw-r--r-- | Cargo.lock | 1 | ||||
| -rw-r--r-- | helix-tui/Cargo.toml | 1 | ||||
| -rw-r--r-- | helix-tui/src/backend/crossterm.rs | 14 |
3 files changed, 14 insertions, 2 deletions
@@ -1202,6 +1202,7 @@ dependencies = [ "helix-core", "helix-view", "log", + "once_cell", "serde", "termini", "unicode-segmentation", diff --git a/helix-tui/Cargo.toml b/helix-tui/Cargo.toml index 3ca7e044..8a6d5367 100644 --- a/helix-tui/Cargo.toml +++ b/helix-tui/Cargo.toml @@ -22,6 +22,7 @@ unicode-segmentation = "1.10" crossterm = { version = "0.26", optional = true } termini = "0.1" serde = { version = "1", "optional" = true, features = ["derive"]} +once_cell = "1.17" log = "~0.4" helix-view = { version = "0.6", path = "../helix-view", features = ["term"] } helix-core = { version = "0.6", path = "../helix-core" } diff --git a/helix-tui/src/backend/crossterm.rs b/helix-tui/src/backend/crossterm.rs index e81c1e00..7c512ce3 100644 --- a/helix-tui/src/backend/crossterm.rs +++ b/helix-tui/src/backend/crossterm.rs @@ -15,6 +15,7 @@ use crossterm::{ Command, }; use helix_view::graphics::{Color, CursorKind, Modifier, Rect, UnderlineStyle}; +use once_cell::sync::OnceCell; use std::{ fmt, io::{self, Write}, @@ -57,6 +58,7 @@ impl Capabilities { pub struct CrosstermBackend<W: Write> { buffer: W, capabilities: Capabilities, + supports_keyboard_enhancement_protocol: OnceCell<bool>, } impl<W> CrosstermBackend<W> @@ -67,8 +69,16 @@ where CrosstermBackend { buffer, capabilities: Capabilities::from_env_or_default(), + supports_keyboard_enhancement_protocol: OnceCell::new(), } } + + #[inline] + fn supports_keyboard_enhancement_protocol(&self) -> io::Result<bool> { + self.supports_keyboard_enhancement_protocol + .get_or_try_init(terminal::supports_keyboard_enhancement) + .copied() + } } impl<W> Write for CrosstermBackend<W> @@ -100,7 +110,7 @@ where if config.enable_mouse_capture { execute!(self.buffer, EnableMouseCapture)?; } - if matches!(terminal::supports_keyboard_enhancement(), Ok(true)) { + if self.supports_keyboard_enhancement_protocol()? { log::debug!("The enhanced keyboard protocol is supported on this terminal"); execute!( self.buffer, @@ -121,7 +131,7 @@ where if config.enable_mouse_capture { execute!(self.buffer, DisableMouseCapture)?; } - if matches!(terminal::supports_keyboard_enhancement(), Ok(true)) { + if self.supports_keyboard_enhancement_protocol()? { execute!(self.buffer, PopKeyboardEnhancementFlags)?; } execute!( |