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helix/helix-view/src/input.rs

319 lines
11 KiB
Rust

//! Input event handling, currently backed by crossterm.
use anyhow::{anyhow, Error};
use helix_core::unicode::width::UnicodeWidthStr;
use serde::de::{self, Deserialize, Deserializer};
use std::fmt;
use crate::keyboard::{KeyCode, KeyModifiers};
/// Represents a key event.
// We use a newtype here because we want to customize Deserialize and Display.
#[derive(Debug, PartialEq, Eq, PartialOrd, Clone, Copy, Hash)]
pub struct KeyEvent {
pub code: KeyCode,
pub modifiers: KeyModifiers,
}
impl KeyEvent {
/// If a character was pressed, return it.
pub fn char(&self) -> Option<char> {
match self.code {
KeyCode::Char(ch) => Some(ch),
_ => None,
}
}
}
pub(crate) mod keys {
pub(crate) const BACKSPACE: &str = "backspace";
pub(crate) const ENTER: &str = "ret";
pub(crate) const LEFT: &str = "left";
pub(crate) const RIGHT: &str = "right";
pub(crate) const UP: &str = "up";
pub(crate) const DOWN: &str = "down";
pub(crate) const HOME: &str = "home";
pub(crate) const END: &str = "end";
pub(crate) const PAGEUP: &str = "pageup";
pub(crate) const PAGEDOWN: &str = "pagedown";
pub(crate) const TAB: &str = "tab";
pub(crate) const BACKTAB: &str = "backtab";
pub(crate) const DELETE: &str = "del";
pub(crate) const INSERT: &str = "ins";
pub(crate) const NULL: &str = "null";
pub(crate) const ESC: &str = "esc";
pub(crate) const SPACE: &str = "space";
pub(crate) const LESS_THAN: &str = "lt";
pub(crate) const GREATER_THAN: &str = "gt";
pub(crate) const PLUS: &str = "plus";
pub(crate) const MINUS: &str = "minus";
pub(crate) const SEMICOLON: &str = "semicolon";
pub(crate) const PERCENT: &str = "percent";
}
impl fmt::Display for KeyEvent {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> std::fmt::Result {
f.write_fmt(format_args!(
"{}{}{}",
if self.modifiers.contains(KeyModifiers::SHIFT) {
"S-"
} else {
""
},
if self.modifiers.contains(KeyModifiers::ALT) {
"A-"
} else {
""
},
if self.modifiers.contains(KeyModifiers::CONTROL) {
"C-"
} else {
""
},
))?;
match self.code {
KeyCode::Backspace => f.write_str(keys::BACKSPACE)?,
KeyCode::Enter => f.write_str(keys::ENTER)?,
KeyCode::Left => f.write_str(keys::LEFT)?,
KeyCode::Right => f.write_str(keys::RIGHT)?,
KeyCode::Up => f.write_str(keys::UP)?,
KeyCode::Down => f.write_str(keys::DOWN)?,
KeyCode::Home => f.write_str(keys::HOME)?,
KeyCode::End => f.write_str(keys::END)?,
KeyCode::PageUp => f.write_str(keys::PAGEUP)?,
KeyCode::PageDown => f.write_str(keys::PAGEDOWN)?,
KeyCode::Tab => f.write_str(keys::TAB)?,
KeyCode::BackTab => f.write_str(keys::BACKTAB)?,
KeyCode::Delete => f.write_str(keys::DELETE)?,
KeyCode::Insert => f.write_str(keys::INSERT)?,
KeyCode::Null => f.write_str(keys::NULL)?,
KeyCode::Esc => f.write_str(keys::ESC)?,
KeyCode::Char(' ') => f.write_str(keys::SPACE)?,
KeyCode::Char('<') => f.write_str(keys::LESS_THAN)?,
KeyCode::Char('>') => f.write_str(keys::GREATER_THAN)?,
KeyCode::Char('+') => f.write_str(keys::PLUS)?,
KeyCode::Char('-') => f.write_str(keys::MINUS)?,
KeyCode::Char(';') => f.write_str(keys::SEMICOLON)?,
KeyCode::Char('%') => f.write_str(keys::PERCENT)?,
KeyCode::F(i) => f.write_fmt(format_args!("F{}", i))?,
KeyCode::Char(c) => f.write_fmt(format_args!("{}", c))?,
};
Ok(())
}
}
impl UnicodeWidthStr for KeyEvent {
fn width(&self) -> usize {
use helix_core::unicode::width::UnicodeWidthChar;
let mut width = match self.code {
KeyCode::Backspace => keys::BACKSPACE.len(),
KeyCode::Enter => keys::ENTER.len(),
KeyCode::Left => keys::LEFT.len(),
KeyCode::Right => keys::RIGHT.len(),
KeyCode::Up => keys::UP.len(),
KeyCode::Down => keys::DOWN.len(),
KeyCode::Home => keys::HOME.len(),
KeyCode::End => keys::END.len(),
KeyCode::PageUp => keys::PAGEUP.len(),
KeyCode::PageDown => keys::PAGEDOWN.len(),
KeyCode::Tab => keys::TAB.len(),
KeyCode::BackTab => keys::BACKTAB.len(),
KeyCode::Delete => keys::DELETE.len(),
KeyCode::Insert => keys::INSERT.len(),
KeyCode::Null => keys::NULL.len(),
KeyCode::Esc => keys::ESC.len(),
KeyCode::Char(' ') => keys::SPACE.len(),
KeyCode::Char('<') => keys::LESS_THAN.len(),
KeyCode::Char('>') => keys::GREATER_THAN.len(),
KeyCode::Char('+') => keys::PLUS.len(),
KeyCode::Char('-') => keys::MINUS.len(),
KeyCode::Char(';') => keys::SEMICOLON.len(),
KeyCode::Char('%') => keys::PERCENT.len(),
KeyCode::F(1..=9) => 2,
KeyCode::F(_) => 3,
KeyCode::Char(c) => c.width().unwrap_or(0),
};
if self.modifiers.contains(KeyModifiers::SHIFT) {
width += 2;
}
if self.modifiers.contains(KeyModifiers::ALT) {
width += 2;
}
if self.modifiers.contains(KeyModifiers::CONTROL) {
width += 2;
}
width
}
fn width_cjk(&self) -> usize {
self.width()
}
}
impl std::str::FromStr for KeyEvent {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let mut tokens: Vec<_> = s.split('-').collect();
let code = match tokens.pop().ok_or_else(|| anyhow!("Missing key code"))? {
keys::BACKSPACE => KeyCode::Backspace,
keys::ENTER => KeyCode::Enter,
keys::LEFT => KeyCode::Left,
keys::RIGHT => KeyCode::Right,
keys::UP => KeyCode::Up,
keys::DOWN => KeyCode::Down,
keys::HOME => KeyCode::Home,
keys::END => KeyCode::End,
keys::PAGEUP => KeyCode::PageUp,
keys::PAGEDOWN => KeyCode::PageDown,
keys::TAB => KeyCode::Tab,
keys::BACKTAB => KeyCode::BackTab,
keys::DELETE => KeyCode::Delete,
keys::INSERT => KeyCode::Insert,
keys::NULL => KeyCode::Null,
keys::ESC => KeyCode::Esc,
keys::SPACE => KeyCode::Char(' '),
keys::LESS_THAN => KeyCode::Char('<'),
keys::GREATER_THAN => KeyCode::Char('>'),
keys::PLUS => KeyCode::Char('+'),
keys::MINUS => KeyCode::Char('-'),
keys::SEMICOLON => KeyCode::Char(';'),
keys::PERCENT => KeyCode::Char('%'),
single if single.chars().count() == 1 => KeyCode::Char(single.chars().next().unwrap()),
function if function.len() > 1 && function.starts_with('F') => {
let function: String = function.chars().skip(1).collect();
let function = str::parse::<u8>(&function)?;
(function > 0 && function < 13)
.then(|| KeyCode::F(function))
.ok_or_else(|| anyhow!("Invalid function key '{}'", function))?
}
invalid => return Err(anyhow!("Invalid key code '{}'", invalid)),
};
let mut modifiers = KeyModifiers::empty();
for token in tokens {
let flag = match token {
"S" => KeyModifiers::SHIFT,
"A" => KeyModifiers::ALT,
"C" => KeyModifiers::CONTROL,
_ => return Err(anyhow!("Invalid key modifier '{}-'", token)),
};
if modifiers.contains(flag) {
return Err(anyhow!("Repeated key modifier '{}-'", token));
}
modifiers.insert(flag);
}
Ok(KeyEvent { code, modifiers })
}
}
impl<'de> Deserialize<'de> for KeyEvent {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let s = String::deserialize(deserializer)?;
s.parse().map_err(de::Error::custom)
}
}
#[cfg(feature = "term")]
impl From<crossterm::event::KeyEvent> for KeyEvent {
fn from(
crossterm::event::KeyEvent { code, modifiers }: crossterm::event::KeyEvent,
) -> KeyEvent {
KeyEvent {
code: code.into(),
modifiers: modifiers.into(),
}
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn parsing_unmodified_keys() {
assert_eq!(
str::parse::<KeyEvent>("backspace").unwrap(),
KeyEvent {
code: KeyCode::Backspace,
modifiers: KeyModifiers::NONE
}
);
assert_eq!(
str::parse::<KeyEvent>("left").unwrap(),
KeyEvent {
code: KeyCode::Left,
modifiers: KeyModifiers::NONE
}
);
assert_eq!(
str::parse::<KeyEvent>(",").unwrap(),
KeyEvent {
code: KeyCode::Char(','),
modifiers: KeyModifiers::NONE
}
);
assert_eq!(
str::parse::<KeyEvent>("w").unwrap(),
KeyEvent {
code: KeyCode::Char('w'),
modifiers: KeyModifiers::NONE
}
);
assert_eq!(
str::parse::<KeyEvent>("F12").unwrap(),
KeyEvent {
code: KeyCode::F(12),
modifiers: KeyModifiers::NONE
}
);
}
#[test]
fn parsing_modified_keys() {
assert_eq!(
str::parse::<KeyEvent>("S-minus").unwrap(),
KeyEvent {
code: KeyCode::Char('-'),
modifiers: KeyModifiers::SHIFT
}
);
assert_eq!(
str::parse::<KeyEvent>("C-A-S-F12").unwrap(),
KeyEvent {
code: KeyCode::F(12),
modifiers: KeyModifiers::SHIFT | KeyModifiers::CONTROL | KeyModifiers::ALT
}
);
assert_eq!(
str::parse::<KeyEvent>("S-C-2").unwrap(),
KeyEvent {
code: KeyCode::Char('2'),
modifiers: KeyModifiers::SHIFT | KeyModifiers::CONTROL
}
);
}
#[test]
fn parsing_nonsensical_keys_fails() {
assert!(str::parse::<KeyEvent>("F13").is_err());
assert!(str::parse::<KeyEvent>("F0").is_err());
assert!(str::parse::<KeyEvent>("aaa").is_err());
assert!(str::parse::<KeyEvent>("S-S-a").is_err());
assert!(str::parse::<KeyEvent>("C-A-S-C-1").is_err());
assert!(str::parse::<KeyEvent>("FU").is_err());
assert!(str::parse::<KeyEvent>("123").is_err());
assert!(str::parse::<KeyEvent>("S--").is_err());
}
}