keymap.rs

  1mod binding;
  2mod context;
  3
  4pub use binding::*;
  5pub use context::*;
  6
  7use crate::{Action, Keystroke, is_no_action};
  8use collections::{HashMap, HashSet};
  9use smallvec::SmallVec;
 10use std::any::TypeId;
 11
 12/// An opaque identifier of which version of the keymap is currently active.
 13/// The keymap's version is changed whenever bindings are added or removed.
 14#[derive(Copy, Clone, Eq, PartialEq, Default)]
 15pub struct KeymapVersion(usize);
 16
 17/// A collection of key bindings for the user's application.
 18#[derive(Default)]
 19pub struct Keymap {
 20    bindings: Vec<KeyBinding>,
 21    binding_indices_by_action_id: HashMap<TypeId, SmallVec<[usize; 3]>>,
 22    no_action_binding_indices: Vec<usize>,
 23    version: KeymapVersion,
 24}
 25
 26/// Index of a binding within a keymap.
 27#[derive(Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
 28pub struct BindingIndex(usize);
 29
 30impl Keymap {
 31    /// Create a new keymap with the given bindings.
 32    pub fn new(bindings: Vec<KeyBinding>) -> Self {
 33        let mut this = Self::default();
 34        this.add_bindings(bindings);
 35        this
 36    }
 37
 38    /// Get the current version of the keymap.
 39    pub fn version(&self) -> KeymapVersion {
 40        self.version
 41    }
 42
 43    /// Add more bindings to the keymap.
 44    pub fn add_bindings<T: IntoIterator<Item = KeyBinding>>(&mut self, bindings: T) {
 45        for binding in bindings {
 46            let action_id = binding.action().as_any().type_id();
 47            if is_no_action(&*binding.action) {
 48                self.no_action_binding_indices.push(self.bindings.len());
 49            } else {
 50                self.binding_indices_by_action_id
 51                    .entry(action_id)
 52                    .or_default()
 53                    .push(self.bindings.len());
 54            }
 55            self.bindings.push(binding);
 56        }
 57
 58        self.version.0 += 1;
 59    }
 60
 61    /// Reset this keymap to its initial state.
 62    pub fn clear(&mut self) {
 63        self.bindings.clear();
 64        self.binding_indices_by_action_id.clear();
 65        self.no_action_binding_indices.clear();
 66        self.version.0 += 1;
 67    }
 68
 69    /// Iterate over all bindings, in the order they were added.
 70    pub fn bindings(&self) -> impl DoubleEndedIterator<Item = &KeyBinding> + ExactSizeIterator {
 71        self.bindings.iter()
 72    }
 73
 74    /// Iterate over all bindings for the given action, in the order they were added. For display,
 75    /// the last binding should take precedence.
 76    pub fn bindings_for_action<'a>(
 77        &'a self,
 78        action: &'a dyn Action,
 79    ) -> impl 'a + DoubleEndedIterator<Item = &'a KeyBinding> {
 80        let action_id = action.type_id();
 81        let binding_indices = self
 82            .binding_indices_by_action_id
 83            .get(&action_id)
 84            .map_or(&[] as _, SmallVec::as_slice)
 85            .iter();
 86
 87        binding_indices.filter_map(|ix| {
 88            let binding = &self.bindings[*ix];
 89            if !binding.action().partial_eq(action) {
 90                return None;
 91            }
 92
 93            for null_ix in &self.no_action_binding_indices {
 94                if null_ix > ix {
 95                    let null_binding = &self.bindings[*null_ix];
 96                    if null_binding.keystrokes == binding.keystrokes {
 97                        let null_binding_matches =
 98                            match (&null_binding.context_predicate, &binding.context_predicate) {
 99                                (None, _) => true,
100                                (Some(_), None) => false,
101                                (Some(null_predicate), Some(predicate)) => {
102                                    null_predicate.is_superset(predicate)
103                                }
104                            };
105                        if null_binding_matches {
106                            return None;
107                        }
108                    }
109                }
110            }
111
112            Some(binding)
113        })
114    }
115
116    /// Returns all bindings that might match the input without checking context. The bindings
117    /// returned in precedence order (reverse of the order they were added to the keymap).
118    pub fn all_bindings_for_input(&self, input: &[Keystroke]) -> Vec<KeyBinding> {
119        self.bindings()
120            .rev()
121            .filter_map(|binding| {
122                binding.match_keystrokes(input).filter(|pending| !pending)?;
123                Some(binding.clone())
124            })
125            .collect()
126    }
127
128    /// Returns a list of bindings that match the given input, and a boolean indicating whether or
129    /// not more bindings might match if the input was longer. Bindings are returned in precedence
130    /// order (higher precedence first, reverse of the order they were added to the keymap).
131    ///
132    /// Precedence is defined by the depth in the tree (matches on the Editor take precedence over
133    /// matches on the Pane, then the Workspace, etc.). Bindings with no context are treated as the
134    /// same as the deepest context.
135    ///
136    /// In the case of multiple bindings at the same depth, the ones added to the keymap later take
137    /// precedence. User bindings are added after built-in bindings so that they take precedence.
138    ///
139    /// If a user has disabled a binding with `"x": null` it will not be returned. Disabled bindings
140    /// are evaluated with the same precedence rules so you can disable a rule in a given context
141    /// only.
142    pub fn bindings_for_input(
143        &self,
144        input: &[Keystroke],
145        context_stack: &[KeyContext],
146    ) -> (SmallVec<[KeyBinding; 1]>, bool) {
147        let mut matched_bindings = SmallVec::<[(usize, BindingIndex, &KeyBinding); 1]>::new();
148        let mut pending_bindings = SmallVec::<[(BindingIndex, &KeyBinding); 1]>::new();
149
150        for (ix, binding) in self.bindings().enumerate().rev() {
151            let Some(depth) = self.binding_enabled(binding, context_stack) else {
152                continue;
153            };
154            let Some(pending) = binding.match_keystrokes(input) else {
155                continue;
156            };
157
158            if !pending {
159                matched_bindings.push((depth, BindingIndex(ix), binding));
160            } else {
161                pending_bindings.push((BindingIndex(ix), binding));
162            }
163        }
164
165        matched_bindings.sort_by(|(depth_a, ix_a, _), (depth_b, ix_b, _)| {
166            depth_b.cmp(depth_a).then(ix_b.cmp(ix_a))
167        });
168
169        let mut bindings: SmallVec<[_; 1]> = SmallVec::new();
170        let mut first_binding_index = None;
171        for (_, ix, binding) in matched_bindings {
172            if is_no_action(&*binding.action) {
173                break;
174            }
175            bindings.push(binding.clone());
176            first_binding_index.get_or_insert(ix);
177        }
178
179        let mut pending = HashSet::default();
180        for (ix, binding) in pending_bindings.into_iter().rev() {
181            if let Some(binding_ix) = first_binding_index
182                && binding_ix > ix
183            {
184                continue;
185            }
186            if is_no_action(&*binding.action) {
187                pending.remove(&&binding.keystrokes);
188                continue;
189            }
190            pending.insert(&binding.keystrokes);
191        }
192
193        (bindings, !pending.is_empty())
194    }
195
196    /// Check if the given binding is enabled, given a certain key context.
197    /// Returns the deepest depth at which the binding matches, or None if it doesn't match.
198    fn binding_enabled(&self, binding: &KeyBinding, contexts: &[KeyContext]) -> Option<usize> {
199        if let Some(predicate) = &binding.context_predicate {
200            predicate.depth_of(contexts)
201        } else {
202            Some(contexts.len())
203        }
204    }
205}
206
207#[cfg(test)]
208mod tests {
209    use super::*;
210    use crate as gpui;
211    use gpui::NoAction;
212
213    actions!(
214        test_only,
215        [ActionAlpha, ActionBeta, ActionGamma, ActionDelta,]
216    );
217
218    #[test]
219    fn test_keymap() {
220        let bindings = [
221            KeyBinding::new("ctrl-a", ActionAlpha {}, None),
222            KeyBinding::new("ctrl-a", ActionBeta {}, Some("pane")),
223            KeyBinding::new("ctrl-a", ActionGamma {}, Some("editor && mode==full")),
224        ];
225
226        let mut keymap = Keymap::default();
227        keymap.add_bindings(bindings.clone());
228
229        // global bindings are enabled in all contexts
230        assert_eq!(keymap.binding_enabled(&bindings[0], &[]), Some(0));
231        assert_eq!(
232            keymap.binding_enabled(&bindings[0], &[KeyContext::parse("terminal").unwrap()]),
233            Some(1)
234        );
235
236        // contextual bindings are enabled in contexts that match their predicate
237        assert_eq!(
238            keymap.binding_enabled(&bindings[1], &[KeyContext::parse("barf x=y").unwrap()]),
239            None
240        );
241        assert_eq!(
242            keymap.binding_enabled(&bindings[1], &[KeyContext::parse("pane x=y").unwrap()]),
243            Some(1)
244        );
245
246        assert_eq!(
247            keymap.binding_enabled(&bindings[2], &[KeyContext::parse("editor").unwrap()]),
248            None
249        );
250        assert_eq!(
251            keymap.binding_enabled(
252                &bindings[2],
253                &[KeyContext::parse("editor mode=full").unwrap()]
254            ),
255            Some(1)
256        );
257    }
258
259    #[test]
260    fn test_depth_precedence() {
261        let bindings = [
262            KeyBinding::new("ctrl-a", ActionBeta {}, Some("pane")),
263            KeyBinding::new("ctrl-a", ActionGamma {}, Some("editor")),
264        ];
265
266        let mut keymap = Keymap::default();
267        keymap.add_bindings(bindings);
268
269        let (result, pending) = keymap.bindings_for_input(
270            &[Keystroke::parse("ctrl-a").unwrap()],
271            &[
272                KeyContext::parse("pane").unwrap(),
273                KeyContext::parse("editor").unwrap(),
274            ],
275        );
276
277        assert!(!pending);
278        assert_eq!(result.len(), 2);
279        assert!(result[0].action.partial_eq(&ActionGamma {}));
280        assert!(result[1].action.partial_eq(&ActionBeta {}));
281    }
282
283    #[test]
284    fn test_keymap_disabled() {
285        let bindings = [
286            KeyBinding::new("ctrl-a", ActionAlpha {}, Some("editor")),
287            KeyBinding::new("ctrl-b", ActionAlpha {}, Some("editor")),
288            KeyBinding::new("ctrl-a", NoAction {}, Some("editor && mode==full")),
289            KeyBinding::new("ctrl-b", NoAction {}, None),
290        ];
291
292        let mut keymap = Keymap::default();
293        keymap.add_bindings(bindings);
294
295        // binding is only enabled in a specific context
296        assert!(
297            keymap
298                .bindings_for_input(
299                    &[Keystroke::parse("ctrl-a").unwrap()],
300                    &[KeyContext::parse("barf").unwrap()],
301                )
302                .0
303                .is_empty()
304        );
305        assert!(
306            !keymap
307                .bindings_for_input(
308                    &[Keystroke::parse("ctrl-a").unwrap()],
309                    &[KeyContext::parse("editor").unwrap()],
310                )
311                .0
312                .is_empty()
313        );
314
315        // binding is disabled in a more specific context
316        assert!(
317            keymap
318                .bindings_for_input(
319                    &[Keystroke::parse("ctrl-a").unwrap()],
320                    &[KeyContext::parse("editor mode=full").unwrap()],
321                )
322                .0
323                .is_empty()
324        );
325
326        // binding is globally disabled
327        assert!(
328            keymap
329                .bindings_for_input(
330                    &[Keystroke::parse("ctrl-b").unwrap()],
331                    &[KeyContext::parse("barf").unwrap()],
332                )
333                .0
334                .is_empty()
335        );
336    }
337
338    #[test]
339    /// Tests for https://github.com/zed-industries/zed/issues/30259
340    fn test_multiple_keystroke_binding_disabled() {
341        let bindings = [
342            KeyBinding::new("space w w", ActionAlpha {}, Some("workspace")),
343            KeyBinding::new("space w w", NoAction {}, Some("editor")),
344        ];
345
346        let mut keymap = Keymap::default();
347        keymap.add_bindings(bindings);
348
349        let space = || Keystroke::parse("space").unwrap();
350        let w = || Keystroke::parse("w").unwrap();
351
352        let space_w = [space(), w()];
353        let space_w_w = [space(), w(), w()];
354
355        let workspace_context = || [KeyContext::parse("workspace").unwrap()];
356
357        let editor_workspace_context = || {
358            [
359                KeyContext::parse("workspace").unwrap(),
360                KeyContext::parse("editor").unwrap(),
361            ]
362        };
363
364        // Ensure `space` results in pending input on the workspace, but not editor
365        let space_workspace = keymap.bindings_for_input(&[space()], &workspace_context());
366        assert!(space_workspace.0.is_empty());
367        assert!(space_workspace.1);
368
369        let space_editor = keymap.bindings_for_input(&[space()], &editor_workspace_context());
370        assert!(space_editor.0.is_empty());
371        assert!(!space_editor.1);
372
373        // Ensure `space w` results in pending input on the workspace, but not editor
374        let space_w_workspace = keymap.bindings_for_input(&space_w, &workspace_context());
375        assert!(space_w_workspace.0.is_empty());
376        assert!(space_w_workspace.1);
377
378        let space_w_editor = keymap.bindings_for_input(&space_w, &editor_workspace_context());
379        assert!(space_w_editor.0.is_empty());
380        assert!(!space_w_editor.1);
381
382        // Ensure `space w w` results in the binding in the workspace, but not in the editor
383        let space_w_w_workspace = keymap.bindings_for_input(&space_w_w, &workspace_context());
384        assert!(!space_w_w_workspace.0.is_empty());
385        assert!(!space_w_w_workspace.1);
386
387        let space_w_w_editor = keymap.bindings_for_input(&space_w_w, &editor_workspace_context());
388        assert!(space_w_w_editor.0.is_empty());
389        assert!(!space_w_w_editor.1);
390
391        // Now test what happens if we have another binding defined AFTER the NoAction
392        // that should result in pending
393        let bindings = [
394            KeyBinding::new("space w w", ActionAlpha {}, Some("workspace")),
395            KeyBinding::new("space w w", NoAction {}, Some("editor")),
396            KeyBinding::new("space w x", ActionAlpha {}, Some("editor")),
397        ];
398        let mut keymap = Keymap::default();
399        keymap.add_bindings(bindings);
400
401        let space_editor = keymap.bindings_for_input(&[space()], &editor_workspace_context());
402        assert!(space_editor.0.is_empty());
403        assert!(space_editor.1);
404
405        // Now test what happens if we have another binding defined BEFORE the NoAction
406        // that should result in pending
407        let bindings = [
408            KeyBinding::new("space w w", ActionAlpha {}, Some("workspace")),
409            KeyBinding::new("space w x", ActionAlpha {}, Some("editor")),
410            KeyBinding::new("space w w", NoAction {}, Some("editor")),
411        ];
412        let mut keymap = Keymap::default();
413        keymap.add_bindings(bindings);
414
415        let space_editor = keymap.bindings_for_input(&[space()], &editor_workspace_context());
416        assert!(space_editor.0.is_empty());
417        assert!(space_editor.1);
418
419        // Now test what happens if we have another binding defined at a higher context
420        // that should result in pending
421        let bindings = [
422            KeyBinding::new("space w w", ActionAlpha {}, Some("workspace")),
423            KeyBinding::new("space w x", ActionAlpha {}, Some("workspace")),
424            KeyBinding::new("space w w", NoAction {}, Some("editor")),
425        ];
426        let mut keymap = Keymap::default();
427        keymap.add_bindings(bindings);
428
429        let space_editor = keymap.bindings_for_input(&[space()], &editor_workspace_context());
430        assert!(space_editor.0.is_empty());
431        assert!(space_editor.1);
432    }
433
434    #[test]
435    fn test_override_multikey() {
436        let bindings = [
437            KeyBinding::new("ctrl-w left", ActionAlpha {}, Some("editor")),
438            KeyBinding::new("ctrl-w", NoAction {}, Some("editor")),
439        ];
440
441        let mut keymap = Keymap::default();
442        keymap.add_bindings(bindings);
443
444        // Ensure `space` results in pending input on the workspace, but not editor
445        let (result, pending) = keymap.bindings_for_input(
446            &[Keystroke::parse("ctrl-w").unwrap()],
447            &[KeyContext::parse("editor").unwrap()],
448        );
449        assert!(result.is_empty());
450        assert!(pending);
451
452        let bindings = [
453            KeyBinding::new("ctrl-w left", ActionAlpha {}, Some("editor")),
454            KeyBinding::new("ctrl-w", ActionBeta {}, Some("editor")),
455        ];
456
457        let mut keymap = Keymap::default();
458        keymap.add_bindings(bindings);
459
460        // Ensure `space` results in pending input on the workspace, but not editor
461        let (result, pending) = keymap.bindings_for_input(
462            &[Keystroke::parse("ctrl-w").unwrap()],
463            &[KeyContext::parse("editor").unwrap()],
464        );
465        assert_eq!(result.len(), 1);
466        assert!(!pending);
467    }
468
469    #[test]
470    fn test_simple_disable() {
471        let bindings = [
472            KeyBinding::new("ctrl-x", ActionAlpha {}, Some("editor")),
473            KeyBinding::new("ctrl-x", NoAction {}, Some("editor")),
474        ];
475
476        let mut keymap = Keymap::default();
477        keymap.add_bindings(bindings);
478
479        // Ensure `space` results in pending input on the workspace, but not editor
480        let (result, pending) = keymap.bindings_for_input(
481            &[Keystroke::parse("ctrl-x").unwrap()],
482            &[KeyContext::parse("editor").unwrap()],
483        );
484        assert!(result.is_empty());
485        assert!(!pending);
486    }
487
488    #[test]
489    fn test_fail_to_disable() {
490        // disabled at the wrong level
491        let bindings = [
492            KeyBinding::new("ctrl-x", ActionAlpha {}, Some("editor")),
493            KeyBinding::new("ctrl-x", NoAction {}, Some("workspace")),
494        ];
495
496        let mut keymap = Keymap::default();
497        keymap.add_bindings(bindings);
498
499        // Ensure `space` results in pending input on the workspace, but not editor
500        let (result, pending) = keymap.bindings_for_input(
501            &[Keystroke::parse("ctrl-x").unwrap()],
502            &[
503                KeyContext::parse("workspace").unwrap(),
504                KeyContext::parse("editor").unwrap(),
505            ],
506        );
507        assert_eq!(result.len(), 1);
508        assert!(!pending);
509    }
510
511    #[test]
512    fn test_disable_deeper() {
513        let bindings = [
514            KeyBinding::new("ctrl-x", ActionAlpha {}, Some("workspace")),
515            KeyBinding::new("ctrl-x", NoAction {}, Some("editor")),
516        ];
517
518        let mut keymap = Keymap::default();
519        keymap.add_bindings(bindings);
520
521        // Ensure `space` results in pending input on the workspace, but not editor
522        let (result, pending) = keymap.bindings_for_input(
523            &[Keystroke::parse("ctrl-x").unwrap()],
524            &[
525                KeyContext::parse("workspace").unwrap(),
526                KeyContext::parse("editor").unwrap(),
527            ],
528        );
529        assert_eq!(result.len(), 0);
530        assert!(!pending);
531    }
532
533    #[test]
534    fn test_pending_match_enabled() {
535        let bindings = [
536            KeyBinding::new("ctrl-x", ActionBeta, Some("vim_mode == normal")),
537            KeyBinding::new("ctrl-x 0", ActionAlpha, Some("Workspace")),
538        ];
539        let mut keymap = Keymap::default();
540        keymap.add_bindings(bindings);
541
542        let matched = keymap.bindings_for_input(
543            &[Keystroke::parse("ctrl-x")].map(Result::unwrap),
544            &[
545                KeyContext::parse("Workspace"),
546                KeyContext::parse("Pane"),
547                KeyContext::parse("Editor vim_mode=normal"),
548            ]
549            .map(Result::unwrap),
550        );
551        assert_eq!(matched.0.len(), 1);
552        assert!(matched.0[0].action.partial_eq(&ActionBeta));
553        assert!(matched.1);
554    }
555
556    #[test]
557    fn test_pending_match_enabled_extended() {
558        let bindings = [
559            KeyBinding::new("ctrl-x", ActionBeta, Some("vim_mode == normal")),
560            KeyBinding::new("ctrl-x 0", NoAction, Some("Workspace")),
561        ];
562        let mut keymap = Keymap::default();
563        keymap.add_bindings(bindings);
564
565        let matched = keymap.bindings_for_input(
566            &[Keystroke::parse("ctrl-x")].map(Result::unwrap),
567            &[
568                KeyContext::parse("Workspace"),
569                KeyContext::parse("Pane"),
570                KeyContext::parse("Editor vim_mode=normal"),
571            ]
572            .map(Result::unwrap),
573        );
574        assert_eq!(matched.0.len(), 1);
575        assert!(matched.0[0].action.partial_eq(&ActionBeta));
576        assert!(!matched.1);
577        let bindings = [
578            KeyBinding::new("ctrl-x", ActionBeta, Some("Workspace")),
579            KeyBinding::new("ctrl-x 0", NoAction, Some("vim_mode == normal")),
580        ];
581        let mut keymap = Keymap::default();
582        keymap.add_bindings(bindings);
583
584        let matched = keymap.bindings_for_input(
585            &[Keystroke::parse("ctrl-x")].map(Result::unwrap),
586            &[
587                KeyContext::parse("Workspace"),
588                KeyContext::parse("Pane"),
589                KeyContext::parse("Editor vim_mode=normal"),
590            ]
591            .map(Result::unwrap),
592        );
593        assert_eq!(matched.0.len(), 1);
594        assert!(matched.0[0].action.partial_eq(&ActionBeta));
595        assert!(!matched.1);
596    }
597
598    #[test]
599    fn test_overriding_prefix() {
600        let bindings = [
601            KeyBinding::new("ctrl-x 0", ActionAlpha, Some("Workspace")),
602            KeyBinding::new("ctrl-x", ActionBeta, Some("vim_mode == normal")),
603        ];
604        let mut keymap = Keymap::default();
605        keymap.add_bindings(bindings);
606
607        let matched = keymap.bindings_for_input(
608            &[Keystroke::parse("ctrl-x")].map(Result::unwrap),
609            &[
610                KeyContext::parse("Workspace"),
611                KeyContext::parse("Pane"),
612                KeyContext::parse("Editor vim_mode=normal"),
613            ]
614            .map(Result::unwrap),
615        );
616        assert_eq!(matched.0.len(), 1);
617        assert!(matched.0[0].action.partial_eq(&ActionBeta));
618        assert!(!matched.1);
619    }
620
621    #[test]
622    fn test_bindings_for_action() {
623        let bindings = [
624            KeyBinding::new("ctrl-a", ActionAlpha {}, Some("pane")),
625            KeyBinding::new("ctrl-b", ActionBeta {}, Some("editor && mode == full")),
626            KeyBinding::new("ctrl-c", ActionGamma {}, Some("workspace")),
627            KeyBinding::new("ctrl-a", NoAction {}, Some("pane && active")),
628            KeyBinding::new("ctrl-b", NoAction {}, Some("editor")),
629        ];
630
631        let mut keymap = Keymap::default();
632        keymap.add_bindings(bindings);
633
634        assert_bindings(&keymap, &ActionAlpha {}, &["ctrl-a"]);
635        assert_bindings(&keymap, &ActionBeta {}, &[]);
636        assert_bindings(&keymap, &ActionGamma {}, &["ctrl-c"]);
637
638        #[track_caller]
639        fn assert_bindings(keymap: &Keymap, action: &dyn Action, expected: &[&str]) {
640            let actual = keymap
641                .bindings_for_action(action)
642                .map(|binding| binding.keystrokes[0].unparse())
643                .collect::<Vec<_>>();
644            assert_eq!(actual, expected, "{:?}", action);
645        }
646    }
647}