1use command_palette_hooks::CommandPaletteFilter;
2use editor::{Anchor, Editor, ExcerptId, SelectionEffects, scroll::Autoscroll};
3use gpui::{
4 App, AppContext as _, Context, Div, Entity, EntityId, EventEmitter, FocusHandle, Focusable,
5 Hsla, InteractiveElement, IntoElement, MouseButton, MouseDownEvent, MouseMoveEvent,
6 ParentElement, Render, ScrollStrategy, SharedString, Styled, UniformListScrollHandle,
7 WeakEntity, Window, actions, div, rems, uniform_list,
8};
9use language::{Buffer, OwnedSyntaxLayer};
10use std::{any::TypeId, mem, ops::Range};
11use theme::ActiveTheme;
12use tree_sitter::{Node, TreeCursor};
13use ui::{
14 ButtonCommon, ButtonLike, Clickable, Color, ContextMenu, FluentBuilder as _, IconButton,
15 IconName, Label, LabelCommon, LabelSize, PopoverMenu, StyledExt, Tooltip, WithScrollbar,
16 h_flex, v_flex,
17};
18use workspace::{
19 Event as WorkspaceEvent, SplitDirection, ToolbarItemEvent, ToolbarItemLocation,
20 ToolbarItemView, Workspace,
21 item::{Item, ItemHandle},
22};
23
24actions!(
25 dev,
26 [
27 /// Opens the syntax tree view for the current file.
28 OpenSyntaxTreeView,
29 ]
30);
31
32actions!(
33 syntax_tree_view,
34 [
35 /// Update the syntax tree view to show the last focused file.
36 UseActiveEditor
37 ]
38);
39
40pub fn init(cx: &mut App) {
41 let syntax_tree_actions = [TypeId::of::<UseActiveEditor>()];
42
43 CommandPaletteFilter::update_global(cx, |this, _| {
44 this.hide_action_types(&syntax_tree_actions);
45 });
46
47 cx.observe_new(move |workspace: &mut Workspace, _, _| {
48 workspace.register_action(move |workspace, _: &OpenSyntaxTreeView, window, cx| {
49 CommandPaletteFilter::update_global(cx, |this, _| {
50 this.show_action_types(&syntax_tree_actions);
51 });
52
53 let active_item = workspace.active_item(cx);
54 let workspace_handle = workspace.weak_handle();
55 let syntax_tree_view = cx.new(|cx| {
56 cx.on_release(move |view: &mut SyntaxTreeView, cx| {
57 if view
58 .workspace_handle
59 .read_with(cx, |workspace, cx| {
60 workspace.item_of_type::<SyntaxTreeView>(cx).is_none()
61 })
62 .unwrap_or_default()
63 {
64 CommandPaletteFilter::update_global(cx, |this, _| {
65 this.hide_action_types(&syntax_tree_actions);
66 });
67 }
68 })
69 .detach();
70
71 SyntaxTreeView::new(workspace_handle, active_item, window, cx)
72 });
73 workspace.split_item(
74 SplitDirection::Right,
75 Box::new(syntax_tree_view),
76 window,
77 cx,
78 )
79 });
80 workspace.register_action(|workspace, _: &UseActiveEditor, window, cx| {
81 if let Some(tree_view) = workspace.item_of_type::<SyntaxTreeView>(cx) {
82 tree_view.update(cx, |view, cx| {
83 view.update_active_editor(&Default::default(), window, cx)
84 })
85 }
86 });
87 })
88 .detach();
89}
90
91pub struct SyntaxTreeView {
92 workspace_handle: WeakEntity<Workspace>,
93 editor: Option<EditorState>,
94 list_scroll_handle: UniformListScrollHandle,
95 /// The last active editor in the workspace. Note that this is specifically not the
96 /// currently shown editor.
97 last_active_editor: Option<Entity<Editor>>,
98 selected_descendant_ix: Option<usize>,
99 hovered_descendant_ix: Option<usize>,
100 focus_handle: FocusHandle,
101}
102
103pub struct SyntaxTreeToolbarItemView {
104 tree_view: Option<Entity<SyntaxTreeView>>,
105 subscription: Option<gpui::Subscription>,
106}
107
108struct EditorState {
109 editor: Entity<Editor>,
110 active_buffer: Option<BufferState>,
111 _subscription: gpui::Subscription,
112}
113
114impl EditorState {
115 fn has_language(&self) -> bool {
116 self.active_buffer
117 .as_ref()
118 .is_some_and(|buffer| buffer.active_layer.is_some())
119 }
120}
121
122#[derive(Clone)]
123struct BufferState {
124 buffer: Entity<Buffer>,
125 excerpt_id: ExcerptId,
126 active_layer: Option<OwnedSyntaxLayer>,
127}
128
129impl SyntaxTreeView {
130 pub fn new(
131 workspace_handle: WeakEntity<Workspace>,
132 active_item: Option<Box<dyn ItemHandle>>,
133 window: &mut Window,
134 cx: &mut Context<Self>,
135 ) -> Self {
136 let mut this = Self {
137 workspace_handle: workspace_handle.clone(),
138 list_scroll_handle: UniformListScrollHandle::new(),
139 editor: None,
140 last_active_editor: None,
141 hovered_descendant_ix: None,
142 selected_descendant_ix: None,
143 focus_handle: cx.focus_handle(),
144 };
145
146 this.handle_item_updated(active_item, window, cx);
147
148 cx.subscribe_in(
149 &workspace_handle.upgrade().unwrap(),
150 window,
151 move |this, workspace, event, window, cx| match event {
152 WorkspaceEvent::ItemAdded { .. } | WorkspaceEvent::ActiveItemChanged => {
153 this.handle_item_updated(workspace.read(cx).active_item(cx), window, cx)
154 }
155 WorkspaceEvent::ItemRemoved { item_id } => {
156 this.handle_item_removed(item_id, window, cx);
157 }
158 _ => {}
159 },
160 )
161 .detach();
162
163 this
164 }
165
166 fn handle_item_updated(
167 &mut self,
168 active_item: Option<Box<dyn ItemHandle>>,
169 window: &mut Window,
170 cx: &mut Context<Self>,
171 ) {
172 let Some(editor) = active_item
173 .filter(|item| item.item_id() != cx.entity_id())
174 .and_then(|item| item.act_as::<Editor>(cx))
175 else {
176 return;
177 };
178
179 if let Some(editor_state) = self.editor.as_ref().filter(|state| state.has_language()) {
180 self.last_active_editor = (editor_state.editor != editor).then_some(editor);
181 } else {
182 self.set_editor(editor, window, cx);
183 }
184 }
185
186 fn handle_item_removed(
187 &mut self,
188 item_id: &EntityId,
189 window: &mut Window,
190 cx: &mut Context<Self>,
191 ) {
192 if self
193 .editor
194 .as_ref()
195 .is_some_and(|state| state.editor.entity_id() == *item_id)
196 {
197 self.editor = None;
198 // Try activating the last active editor if there is one
199 self.update_active_editor(&Default::default(), window, cx);
200 cx.notify();
201 }
202 }
203
204 fn update_active_editor(
205 &mut self,
206 _: &UseActiveEditor,
207 window: &mut Window,
208 cx: &mut Context<Self>,
209 ) {
210 let Some(editor) = self.last_active_editor.take() else {
211 return;
212 };
213 self.set_editor(editor, window, cx);
214 }
215
216 fn set_editor(&mut self, editor: Entity<Editor>, window: &mut Window, cx: &mut Context<Self>) {
217 if let Some(state) = &self.editor {
218 if state.editor == editor {
219 return;
220 }
221 editor.update(cx, |editor, cx| {
222 editor.clear_background_highlights::<Self>(cx)
223 });
224 }
225
226 let subscription = cx.subscribe_in(&editor, window, |this, _, event, window, cx| {
227 let did_reparse = match event {
228 editor::EditorEvent::Reparsed(_) => true,
229 editor::EditorEvent::SelectionsChanged { .. } => false,
230 _ => return,
231 };
232 this.editor_updated(did_reparse, window, cx);
233 });
234
235 self.editor = Some(EditorState {
236 editor,
237 _subscription: subscription,
238 active_buffer: None,
239 });
240 self.editor_updated(true, window, cx);
241 }
242
243 fn editor_updated(
244 &mut self,
245 did_reparse: bool,
246 window: &mut Window,
247 cx: &mut Context<Self>,
248 ) -> Option<()> {
249 // Find which excerpt the cursor is in, and the position within that excerpted buffer.
250 let editor_state = self.editor.as_mut()?;
251 let snapshot = editor_state
252 .editor
253 .update(cx, |editor, cx| editor.snapshot(window, cx));
254 let (buffer, range, excerpt_id) = editor_state.editor.update(cx, |editor, cx| {
255 let selection_range = editor.selections.last::<usize>(cx).range();
256 let multi_buffer = editor.buffer().read(cx);
257 let (buffer, range, excerpt_id) = snapshot
258 .buffer_snapshot()
259 .range_to_buffer_ranges(selection_range)
260 .pop()?;
261 let buffer = multi_buffer.buffer(buffer.remote_id()).unwrap();
262 Some((buffer, range, excerpt_id))
263 })?;
264
265 // If the cursor has moved into a different excerpt, retrieve a new syntax layer
266 // from that buffer.
267 let buffer_state = editor_state
268 .active_buffer
269 .get_or_insert_with(|| BufferState {
270 buffer: buffer.clone(),
271 excerpt_id,
272 active_layer: None,
273 });
274 let mut prev_layer = None;
275 if did_reparse {
276 prev_layer = buffer_state.active_layer.take();
277 }
278 if buffer_state.buffer != buffer || buffer_state.excerpt_id != excerpt_id {
279 buffer_state.buffer = buffer.clone();
280 buffer_state.excerpt_id = excerpt_id;
281 buffer_state.active_layer = None;
282 }
283
284 let layer = match &mut buffer_state.active_layer {
285 Some(layer) => layer,
286 None => {
287 let snapshot = buffer.read(cx).snapshot();
288 let layer = if let Some(prev_layer) = prev_layer {
289 let prev_range = prev_layer.node().byte_range();
290 snapshot
291 .syntax_layers()
292 .filter(|layer| layer.language == &prev_layer.language)
293 .min_by_key(|layer| {
294 let range = layer.node().byte_range();
295 ((range.start as i64) - (prev_range.start as i64)).abs()
296 + ((range.end as i64) - (prev_range.end as i64)).abs()
297 })?
298 } else {
299 snapshot.syntax_layers().next()?
300 };
301 buffer_state.active_layer.insert(layer.to_owned())
302 }
303 };
304
305 // Within the active layer, find the syntax node under the cursor,
306 // and scroll to it.
307 let mut cursor = layer.node().walk();
308 while cursor.goto_first_child_for_byte(range.start).is_some() {
309 if !range.is_empty() && cursor.node().end_byte() == range.start {
310 cursor.goto_next_sibling();
311 }
312 }
313
314 // Ascend to the smallest ancestor that contains the range.
315 loop {
316 let node_range = cursor.node().byte_range();
317 if node_range.start <= range.start && node_range.end >= range.end {
318 break;
319 }
320 if !cursor.goto_parent() {
321 break;
322 }
323 }
324
325 let descendant_ix = cursor.descendant_index();
326 self.selected_descendant_ix = Some(descendant_ix);
327 self.list_scroll_handle
328 .scroll_to_item(descendant_ix, ScrollStrategy::Center);
329
330 cx.notify();
331 Some(())
332 }
333
334 fn update_editor_with_range_for_descendant_ix(
335 &self,
336 descendant_ix: usize,
337 window: &mut Window,
338 cx: &mut Context<Self>,
339 mut f: impl FnMut(&mut Editor, Range<Anchor>, &mut Window, &mut Context<Editor>),
340 ) -> Option<()> {
341 let editor_state = self.editor.as_ref()?;
342 let buffer_state = editor_state.active_buffer.as_ref()?;
343 let layer = buffer_state.active_layer.as_ref()?;
344
345 // Find the node.
346 let mut cursor = layer.node().walk();
347 cursor.goto_descendant(descendant_ix);
348 let node = cursor.node();
349 let range = node.byte_range();
350
351 // Build a text anchor range.
352 let buffer = buffer_state.buffer.read(cx);
353 let range = buffer.anchor_before(range.start)..buffer.anchor_after(range.end);
354
355 // Build a multibuffer anchor range.
356 let multibuffer = editor_state.editor.read(cx).buffer();
357 let multibuffer = multibuffer.read(cx).snapshot(cx);
358 let excerpt_id = buffer_state.excerpt_id;
359 let range = multibuffer.anchor_range_in_excerpt(excerpt_id, range)?;
360
361 // Update the editor with the anchor range.
362 editor_state.editor.update(cx, |editor, cx| {
363 f(editor, range, window, cx);
364 });
365 Some(())
366 }
367
368 fn render_node(cursor: &TreeCursor, depth: u32, selected: bool, cx: &App) -> Div {
369 let colors = cx.theme().colors();
370 let mut row = h_flex();
371 if let Some(field_name) = cursor.field_name() {
372 row = row.children([Label::new(field_name).color(Color::Info), Label::new(": ")]);
373 }
374
375 let node = cursor.node();
376 row.child(if node.is_named() {
377 Label::new(node.kind()).color(Color::Default)
378 } else {
379 Label::new(format!("\"{}\"", node.kind())).color(Color::Created)
380 })
381 .child(
382 div()
383 .child(Label::new(format_node_range(node)).color(Color::Muted))
384 .pl_1(),
385 )
386 .text_bg(if selected {
387 colors.element_selected
388 } else {
389 Hsla::default()
390 })
391 .pl(rems(depth as f32))
392 .hover(|style| style.bg(colors.element_hover))
393 }
394
395 fn compute_items(
396 &mut self,
397 layer: &OwnedSyntaxLayer,
398 range: Range<usize>,
399 cx: &Context<Self>,
400 ) -> Vec<Div> {
401 let mut items = Vec::new();
402 let mut cursor = layer.node().walk();
403 let mut descendant_ix = range.start;
404 cursor.goto_descendant(descendant_ix);
405 let mut depth = cursor.depth();
406 let mut visited_children = false;
407 while descendant_ix < range.end {
408 if visited_children {
409 if cursor.goto_next_sibling() {
410 visited_children = false;
411 } else if cursor.goto_parent() {
412 depth -= 1;
413 } else {
414 break;
415 }
416 } else {
417 items.push(
418 Self::render_node(
419 &cursor,
420 depth,
421 Some(descendant_ix) == self.selected_descendant_ix,
422 cx,
423 )
424 .on_mouse_down(
425 MouseButton::Left,
426 cx.listener(move |tree_view, _: &MouseDownEvent, window, cx| {
427 tree_view.update_editor_with_range_for_descendant_ix(
428 descendant_ix,
429 window,
430 cx,
431 |editor, mut range, window, cx| {
432 // Put the cursor at the beginning of the node.
433 mem::swap(&mut range.start, &mut range.end);
434
435 editor.change_selections(
436 SelectionEffects::scroll(Autoscroll::newest()),
437 window,
438 cx,
439 |selections| {
440 selections.select_ranges(vec![range]);
441 },
442 );
443 },
444 );
445 }),
446 )
447 .on_mouse_move(cx.listener(
448 move |tree_view, _: &MouseMoveEvent, window, cx| {
449 if tree_view.hovered_descendant_ix != Some(descendant_ix) {
450 tree_view.hovered_descendant_ix = Some(descendant_ix);
451 tree_view.update_editor_with_range_for_descendant_ix(
452 descendant_ix,
453 window,
454 cx,
455 |editor, range, _, cx| {
456 editor.clear_background_highlights::<Self>(cx);
457 editor.highlight_background::<Self>(
458 &[range],
459 |theme| {
460 theme
461 .colors()
462 .editor_document_highlight_write_background
463 },
464 cx,
465 );
466 },
467 );
468 cx.notify();
469 }
470 },
471 )),
472 );
473 descendant_ix += 1;
474 if cursor.goto_first_child() {
475 depth += 1;
476 } else {
477 visited_children = true;
478 }
479 }
480 }
481 items
482 }
483}
484
485impl Render for SyntaxTreeView {
486 fn render(&mut self, window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
487 div()
488 .flex_1()
489 .bg(cx.theme().colors().editor_background)
490 .map(|this| {
491 let editor_state = self.editor.as_ref();
492
493 if let Some(layer) = editor_state
494 .and_then(|editor| editor.active_buffer.as_ref())
495 .and_then(|buffer| buffer.active_layer.as_ref())
496 {
497 let layer = layer.clone();
498 this.child(
499 uniform_list(
500 "SyntaxTreeView",
501 layer.node().descendant_count(),
502 cx.processor(move |this, range: Range<usize>, _, cx| {
503 this.compute_items(&layer, range, cx)
504 }),
505 )
506 .size_full()
507 .track_scroll(self.list_scroll_handle.clone())
508 .text_bg(cx.theme().colors().background)
509 .into_any_element(),
510 )
511 .vertical_scrollbar_for(self.list_scroll_handle.clone(), window, cx)
512 .into_any_element()
513 } else {
514 let inner_content = v_flex()
515 .items_center()
516 .text_center()
517 .gap_2()
518 .max_w_3_5()
519 .map(|this| {
520 if editor_state.is_some_and(|state| !state.has_language()) {
521 this.child(Label::new("Current editor has no associated language"))
522 .child(
523 Label::new(concat!(
524 "Try assigning a language or",
525 "switching to a different buffer"
526 ))
527 .size(LabelSize::Small),
528 )
529 } else {
530 this.child(Label::new("Not attached to an editor")).child(
531 Label::new("Focus an editor to show a new tree view")
532 .size(LabelSize::Small),
533 )
534 }
535 });
536
537 this.h_flex()
538 .size_full()
539 .justify_center()
540 .child(inner_content)
541 .into_any_element()
542 }
543 })
544 }
545}
546
547impl EventEmitter<()> for SyntaxTreeView {}
548
549impl Focusable for SyntaxTreeView {
550 fn focus_handle(&self, _: &App) -> gpui::FocusHandle {
551 self.focus_handle.clone()
552 }
553}
554
555impl Item for SyntaxTreeView {
556 type Event = ();
557
558 fn to_item_events(_: &Self::Event, _: impl FnMut(workspace::item::ItemEvent)) {}
559
560 fn tab_content_text(&self, _detail: usize, _cx: &App) -> SharedString {
561 "Syntax Tree".into()
562 }
563
564 fn telemetry_event_text(&self) -> Option<&'static str> {
565 None
566 }
567
568 fn clone_on_split(
569 &self,
570 _: Option<workspace::WorkspaceId>,
571 window: &mut Window,
572 cx: &mut Context<Self>,
573 ) -> Option<Entity<Self>>
574 where
575 Self: Sized,
576 {
577 Some(cx.new(|cx| {
578 let mut clone = Self::new(self.workspace_handle.clone(), None, window, cx);
579 if let Some(editor) = &self.editor {
580 clone.set_editor(editor.editor.clone(), window, cx)
581 }
582 clone
583 }))
584 }
585}
586
587impl Default for SyntaxTreeToolbarItemView {
588 fn default() -> Self {
589 Self::new()
590 }
591}
592
593impl SyntaxTreeToolbarItemView {
594 pub fn new() -> Self {
595 Self {
596 tree_view: None,
597 subscription: None,
598 }
599 }
600
601 fn render_menu(&mut self, cx: &mut Context<Self>) -> Option<PopoverMenu<ContextMenu>> {
602 let tree_view = self.tree_view.as_ref()?;
603 let tree_view = tree_view.read(cx);
604
605 let editor_state = tree_view.editor.as_ref()?;
606 let buffer_state = editor_state.active_buffer.as_ref()?;
607 let active_layer = buffer_state.active_layer.clone()?;
608 let active_buffer = buffer_state.buffer.read(cx).snapshot();
609
610 let view = cx.entity();
611 Some(
612 PopoverMenu::new("Syntax Tree")
613 .trigger(Self::render_header(&active_layer))
614 .menu(move |window, cx| {
615 ContextMenu::build(window, cx, |mut menu, window, _| {
616 for (layer_ix, layer) in active_buffer.syntax_layers().enumerate() {
617 menu = menu.entry(
618 format!(
619 "{} {}",
620 layer.language.name(),
621 format_node_range(layer.node())
622 ),
623 None,
624 window.handler_for(&view, move |view, window, cx| {
625 view.select_layer(layer_ix, window, cx);
626 }),
627 );
628 }
629 menu
630 })
631 .into()
632 }),
633 )
634 }
635
636 fn select_layer(
637 &mut self,
638 layer_ix: usize,
639 window: &mut Window,
640 cx: &mut Context<Self>,
641 ) -> Option<()> {
642 let tree_view = self.tree_view.as_ref()?;
643 tree_view.update(cx, |view, cx| {
644 let editor_state = view.editor.as_mut()?;
645 let buffer_state = editor_state.active_buffer.as_mut()?;
646 let snapshot = buffer_state.buffer.read(cx).snapshot();
647 let layer = snapshot.syntax_layers().nth(layer_ix)?;
648 buffer_state.active_layer = Some(layer.to_owned());
649 view.selected_descendant_ix = None;
650 cx.notify();
651 view.focus_handle.focus(window);
652 Some(())
653 })
654 }
655
656 fn render_header(active_layer: &OwnedSyntaxLayer) -> ButtonLike {
657 ButtonLike::new("syntax tree header")
658 .child(Label::new(active_layer.language.name()))
659 .child(Label::new(format_node_range(active_layer.node())))
660 }
661
662 fn render_update_button(&mut self, cx: &mut Context<Self>) -> Option<IconButton> {
663 self.tree_view.as_ref().and_then(|view| {
664 view.update(cx, |view, cx| {
665 view.last_active_editor.as_ref().map(|editor| {
666 IconButton::new("syntax-view-update", IconName::RotateCw)
667 .tooltip({
668 let active_tab_name = editor.read_with(cx, |editor, cx| {
669 editor.tab_content_text(Default::default(), cx)
670 });
671
672 Tooltip::text(format!("Update view to '{active_tab_name}'"))
673 })
674 .on_click(cx.listener(|this, _, window, cx| {
675 this.update_active_editor(&Default::default(), window, cx);
676 }))
677 })
678 })
679 })
680 }
681}
682
683fn format_node_range(node: Node) -> String {
684 let start = node.start_position();
685 let end = node.end_position();
686 format!(
687 "[{}:{} - {}:{}]",
688 start.row + 1,
689 start.column + 1,
690 end.row + 1,
691 end.column + 1,
692 )
693}
694
695impl Render for SyntaxTreeToolbarItemView {
696 fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
697 h_flex()
698 .gap_1()
699 .children(self.render_menu(cx))
700 .children(self.render_update_button(cx))
701 }
702}
703
704impl EventEmitter<ToolbarItemEvent> for SyntaxTreeToolbarItemView {}
705
706impl ToolbarItemView for SyntaxTreeToolbarItemView {
707 fn set_active_pane_item(
708 &mut self,
709 active_pane_item: Option<&dyn ItemHandle>,
710 window: &mut Window,
711 cx: &mut Context<Self>,
712 ) -> ToolbarItemLocation {
713 if let Some(item) = active_pane_item
714 && let Some(view) = item.downcast::<SyntaxTreeView>()
715 {
716 self.tree_view = Some(view.clone());
717 self.subscription = Some(cx.observe_in(&view, window, |_, _, _, cx| cx.notify()));
718 return ToolbarItemLocation::PrimaryLeft;
719 }
720 self.tree_view = None;
721 self.subscription = None;
722 ToolbarItemLocation::Hidden
723 }
724}