1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431
//! Provides mappings and actions to change the behavior of [`Prompt`] when parsing the user input. //! //! There is a built-in set of default [`Action`]s that will be executed upon user interaction. //! These are meant to feel natural when coming from the default terminal, while also adding further //! functionality and editing commands. //! //! However, bindings that override the default behavior can be given to [`Prompt`] to cause //! a different [`Action`] to be taken. //! //! # Examples //! //! ``` //! use rucline::Prompt; //! use rucline::actions::{Action, Event, KeyBindings}; //! use crossterm::event::KeyCode; //! //! let mut bindings = KeyBindings::new(); //! bindings.insert(Event::from(KeyCode::Tab), Action::Write('\t')); //! //! let prompt = Prompt::new().overrider(&bindings); //! ``` //! //! ``` //! use rucline::Prompt; //! use rucline::actions::{Action, Context, Event, KeyBindings}; //! use crossterm::event::KeyCode; //! //! let prompt = Prompt::new().overrider(&|e, _: &dyn Context| if e == Event::from(KeyCode::Tab) { //! Some(Action::Write('\t')) //! } else { //! None //! }); //! ``` //! //! # Overriding a default action //! //! The [`KeyBindings`] map provides a way to store the association //! between [`Event`] and [`Action`] which will override the default behavior. //! //! ``` //! use rucline::actions::{Action, Event, KeyBindings}; //! use crossterm::event::KeyCode; //! //! let mut bindings = KeyBindings::new(); //! bindings.insert(Event::from(KeyCode::Tab), Action::Write('\t')); //! ``` //! //! # Disabling a default action //! //! To explicitly remove an [`Action`] from the default behavior, the [`Noop`] action can be //! set as the override. //! //! ``` //! use rucline::actions::{Action, Event, KeyBindings}; //! use crossterm::event::KeyCode; //! //! let mut bindings = KeyBindings::new(); //! bindings.insert(Event::from(KeyCode::Tab), Action::Noop); //! ``` //! //! # Saving key binding configurations //! //! If the feature `serialize` is enabled, [`KeyBindings`] can be serialized, stored, and loaded //! at runtime. //! //! # Default behavior //! //! In the absence of [`KeyBindings`] or an entry for a given [`Event`], the default behavior //! will be as follows: //! //! ```no_run //! # fn default_action(event: rucline::actions::Event) -> rucline::actions::Action { //! # use crossterm::event::KeyCode; //! # use rucline::actions::{Action::*, Direction::*, Range::*, Scope::* }; //! # match event.code { //! KeyCode::Enter => Accept, //! KeyCode::Esc => Cancel, //! KeyCode::Tab => Suggest(Forward), //! KeyCode::BackTab => Suggest(Backward), //! KeyCode::Backspace => Delete(Relative(Single, Backward)), //! KeyCode::Delete => Delete(Relative(Single, Forward)), //! KeyCode::Right => Move(Single, Forward), //! KeyCode::Left => Move(Single, Backward), //! KeyCode::Home => Move(Line, Backward), //! KeyCode::End => Move(Line, Forward), //! KeyCode::Char(c) => { //! if event.modifiers == crossterm::event::KeyModifiers::CONTROL { //! match c { //! 'm' | 'd' => Accept, //! 'c' => Cancel, //! //! 'b' => Move(Single, Backward), //! 'f' => Move(Single, Forward), //! 'a' => Move(Line, Backward), //! 'e' => Move(Line, Forward), //! //! 'j' => Delete(Relative(Word, Backward)), //! 'k' => Delete(Relative(Word, Forward)), //! 'h' => Delete(Relative(Line, Backward)), //! 'l' => Delete(Relative(Line, Forward)), //! 'w' => Delete(WholeWord), //! 'u' => Delete(WholeLine), //! _ => Noop, //! } //! } else if event.modifiers == crossterm::event::KeyModifiers::ALT { //! match c { //! 'b' => Move(Word, Backward), //! 'f' => Move(Word, Forward), //! _ => Noop, //! } //! } else { //! Write(c) //! } //! } //! _ => Noop, //! # }} //! ``` //! //! [`Prompt`]: ../prompt/struct.Prompt.html //! [`KeyBindings`]: type.KeyBindings.html //! [`Event`]: type.Event.html //! [`Action`]: enum.Action.html //! [`Noop`]: enum.Action.html#variant.Noop pub use crate::Context; #[cfg(feature = "serde")] use serde::{Deserialize, Serialize}; /// Alias to `crossterm::event::KeyEvent` from [`crossterm`](https://docs.rs/crossterm/) pub type Event = crossterm::event::KeyEvent; /// Alias to [`HashMap<Event, Action>`](std::collections::HashMap) pub type KeyBindings = std::collections::HashMap<Event, Action>; /// An action that can be performed while reading a line #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] pub enum Action { /// Write a single character where the cursor is Write(char), /// Delete a section based on the cursor, defined by [`Scope`](enum.Scope.html) Delete(Scope), /// Move the cursor for a [`Range`](enum.Range.html) in a [`Direction`](enum.Direction.html) Move(Range, Direction), /// Trigger the [`suggester`](../completion/trait.Suggester.html) Suggest(Direction), /// Accept [`Range`](enum.Range.html) from the current completion presented by /// [`completer`](../completion/trait.Completer.html), if any Complete(Range), /// Accept the current line Accept, /// Cancel the suggestions, if any. Else, discard the whole line Cancel, /// Do nothing and wait for the next [`Event`](type.Event.html) Noop, } /// The scope an [`Action`](enum.Action.html) should be applied on #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] pub enum Scope { /// Represents a whole line WholeLine, /// Represents a whole word WholeWord, /// Represents a relative scope, with a [`Range`](enum.Range.html) /// and [`Direction`](enum.Direction.html) Relative(Range, Direction), } /// The range an [`Action`](enum.Action.html) should extend for #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] pub enum Range { /// Represents the remainder of the line Line, /// Represents a single word Word, /// Represents a single character Single, } /// The direction an [`Action`](enum.Action.html) may take #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] pub enum Direction { /// Represents a "left" or "down" direction Forward, /// Represents a "right" or "up" direction Backward, } /// Overrides the behavior for a given [`Event`]. /// /// This trait has a convenience implementation for [`KeyBindings`] and also a conversion /// from lambdas. /// /// # Example /// /// ``` /// use rucline::Prompt; /// use rucline::actions::{Action, Context, Event}; /// use crossterm::event::KeyCode; /// /// let prompt = Prompt::new().overrider(&|e, _: &dyn Context| if e == Event::from(KeyCode::Tab) { /// Some(Action::Write('\t')) /// } else { /// None /// }); /// ``` /// /// [`Event`]: type.Event.html /// [`KeyBindings`]: type.KeyBindings.html pub trait Overrider { /// Overrides the behavior for the given [`Event`]. /// /// [`Context`] will contain the current context of the prompt, in case the behavior should /// be contextual. /// /// # Arguments /// * [`event`] - The incoming event to be processed. /// * [`context`] - The current context in which this event is coming in. /// /// [`Event`]: type.Event.html /// [`Context`]: ../prompt/context/trait.Context.html fn override_for(&self, event: Event, context: &dyn Context) -> Option<Action>; } impl Overrider for KeyBindings { fn override_for(&self, event: Event, _: &dyn Context) -> Option<Action> { self.get(&event).copied() } } impl<F> Overrider for F where F: Fn(Event, &dyn Context) -> Option<Action>, { fn override_for(&self, event: Event, context: &dyn Context) -> Option<Action> { self(event, context) } } pub(super) fn action_for( overrides: Option<&dyn Overrider>, event: Event, context: &impl Context, ) -> Action { if let Some(action) = overrides .as_ref() .and_then(|b| b.override_for(event, context)) { action } else { default_action(event, context) } } #[inline] fn control_pressed(event: &Event) -> bool { event.modifiers == crossterm::event::KeyModifiers::CONTROL } #[inline] fn alt_pressed(event: &Event) -> bool { event.modifiers == crossterm::event::KeyModifiers::ALT } #[inline] fn complete_if_at_end_else_move(context: &impl Context, range: Range) -> Action { if context.cursor() == context.buffer().len() { if range == Range::Word { Action::Complete(Range::Word) } else { Action::Complete(Range::Line) } } else { Action::Move(range, Direction::Forward) } } // TODO: Investigate '\n' being parsed and 'ENTER' fn default_action(event: Event, context: &impl Context) -> Action { use crossterm::event::KeyCode; use Action::{Accept, Cancel, Delete, Move, Noop, Suggest, Write}; use Direction::{Backward, Forward}; use Range::{Line, Single, Word}; use Scope::{Relative, WholeLine, WholeWord}; match event.code { KeyCode::Enter => Accept, KeyCode::Esc => Cancel, KeyCode::Tab => Suggest(Forward), KeyCode::BackTab => Suggest(Backward), KeyCode::Backspace => Delete(Relative(Single, Backward)), KeyCode::Delete => Delete(Relative(Single, Forward)), KeyCode::Right => complete_if_at_end_else_move(context, Single), KeyCode::Left => Move(Single, Backward), KeyCode::Home => Move(Line, Backward), KeyCode::End => complete_if_at_end_else_move(context, Line), KeyCode::Char(c) => { if control_pressed(&event) { match c { 'm' | 'd' => Accept, 'c' => Cancel, 'b' => Move(Single, Backward), 'f' => complete_if_at_end_else_move(context, Single), 'a' => Move(Line, Backward), 'e' => complete_if_at_end_else_move(context, Line), 'j' => Delete(Relative(Word, Backward)), 'k' => Delete(Relative(Word, Forward)), 'h' => Delete(Relative(Line, Backward)), 'l' => Delete(Relative(Line, Forward)), 'w' => Delete(WholeWord), 'u' => Delete(WholeLine), _ => Noop, } } else if alt_pressed(&event) { match c { 'b' => Move(Word, Backward), 'f' => complete_if_at_end_else_move(context, Word), _ => Noop, } } else { Write(c) } } _ => Noop, } } #[cfg(test)] mod test { use super::{action_for, default_action, Action, Direction, Event, Range}; use crate::test::mock::Context as Mock; #[test] fn should_complete_if_at_end() { use crossterm::event::KeyCode::{Char, End, Right}; use crossterm::event::KeyModifiers; use Action::{Complete, Move}; use Direction::Forward; use Range::{Line, Single, Word}; let mut c = Mock::from("a"); assert_eq!(default_action(Event::from(Right), &c), Complete(Line)); assert_eq!(default_action(Event::from(End), &c), Complete(Line)); assert_eq!( default_action(Event::new(Char('f'), KeyModifiers::CONTROL), &c), Complete(Line) ); assert_eq!( default_action(Event::new(Char('f'), KeyModifiers::ALT), &c), Complete(Word) ); c.cursor = 0; assert_eq!( default_action(Event::from(Right), &c), Move(Single, Forward) ); assert_eq!(default_action(Event::from(End), &c), Move(Line, Forward)); assert_eq!( default_action(Event::new(Char('f'), KeyModifiers::CONTROL), &c), Move(Single, Forward) ); assert_eq!( default_action(Event::new(Char('f'), KeyModifiers::ALT), &c), Move(Word, Forward) ); } #[test] fn should_default_if_no_mapping() { use crossterm::event::KeyCode::Tab; let action = action_for(None, Event::from(Tab), &Mock::empty()); assert_eq!(action, Action::Suggest(Direction::Forward)); } mod basic { use super::super::{action_for, Action, Direction, Event, KeyBindings}; use super::Mock; use crossterm::event::KeyCode::Tab; #[test] fn should_default_if_event_missing_form_mapping() { let overrider = KeyBindings::new(); let action = action_for(Some(&overrider), Event::from(Tab), &Mock::empty()); assert_eq!(action, Action::Suggest(Direction::Forward)); } #[test] fn should_override_if_defined() { let mut bindings = KeyBindings::new(); bindings.insert(Event::from(Tab), Action::Write('\t')); let action = action_for(Some(&bindings), Event::from(Tab), &Mock::empty()); assert_eq!(action, Action::Write('\t')); } } mod lambda { use super::super::{action_for, Action, Context, Direction, Event}; use super::Mock; use crossterm::event::KeyCode::Tab; #[test] fn should_default_if_event_missing_form_mapping() { let overrider = |_, _: &dyn Context| None; let action = action_for(Some(&overrider), Event::from(Tab), &Mock::empty()); assert_eq!(action, Action::Suggest(Direction::Forward)); } #[test] fn should_override_if_defined() { let overrider = |e, _: &dyn Context| { if e == Event::from(Tab) { Some(Action::Write('\t')) } else { None } }; let action = action_for(Some(&overrider), Event::from(Tab), &Mock::empty()); assert_eq!(action, Action::Write('\t')); } } }