1use editor::{Anchor, Editor, ExcerptId, SelectionEffects, scroll::Autoscroll};
2use gpui::{
3 App, AppContext as _, Context, Div, Entity, EventEmitter, FocusHandle, Focusable, Hsla,
4 InteractiveElement, IntoElement, MouseButton, MouseDownEvent, MouseMoveEvent, ParentElement,
5 Render, ScrollStrategy, SharedString, Styled, UniformListScrollHandle, WeakEntity, Window,
6 actions, div, rems, uniform_list,
7};
8use language::{Buffer, OwnedSyntaxLayer};
9use std::{mem, ops::Range};
10use theme::ActiveTheme;
11use tree_sitter::{Node, TreeCursor};
12use ui::{ButtonLike, Color, ContextMenu, Label, LabelCommon, PopoverMenu, h_flex};
13use workspace::{
14 SplitDirection, ToolbarItemEvent, ToolbarItemLocation, ToolbarItemView, Workspace,
15 item::{Item, ItemHandle},
16};
17
18actions!(
19 dev,
20 [
21 /// Opens the syntax tree view for the current file.
22 OpenSyntaxTreeView
23 ]
24);
25
26pub fn init(cx: &mut App) {
27 cx.observe_new(|workspace: &mut Workspace, _, _| {
28 workspace.register_action(|workspace, _: &OpenSyntaxTreeView, window, cx| {
29 let active_item = workspace.active_item(cx);
30 let workspace_handle = workspace.weak_handle();
31 let syntax_tree_view =
32 cx.new(|cx| SyntaxTreeView::new(workspace_handle, active_item, window, cx));
33 workspace.split_item(
34 SplitDirection::Right,
35 Box::new(syntax_tree_view),
36 window,
37 cx,
38 )
39 });
40 })
41 .detach();
42}
43
44pub struct SyntaxTreeView {
45 workspace_handle: WeakEntity<Workspace>,
46 editor: Option<EditorState>,
47 list_scroll_handle: UniformListScrollHandle,
48 selected_descendant_ix: Option<usize>,
49 hovered_descendant_ix: Option<usize>,
50 focus_handle: FocusHandle,
51}
52
53pub struct SyntaxTreeToolbarItemView {
54 tree_view: Option<Entity<SyntaxTreeView>>,
55 subscription: Option<gpui::Subscription>,
56}
57
58struct EditorState {
59 editor: Entity<Editor>,
60 active_buffer: Option<BufferState>,
61 _subscription: gpui::Subscription,
62}
63
64#[derive(Clone)]
65struct BufferState {
66 buffer: Entity<Buffer>,
67 excerpt_id: ExcerptId,
68 active_layer: Option<OwnedSyntaxLayer>,
69}
70
71impl SyntaxTreeView {
72 pub fn new(
73 workspace_handle: WeakEntity<Workspace>,
74 active_item: Option<Box<dyn ItemHandle>>,
75 window: &mut Window,
76 cx: &mut Context<Self>,
77 ) -> Self {
78 let mut this = Self {
79 workspace_handle: workspace_handle.clone(),
80 list_scroll_handle: UniformListScrollHandle::new(),
81 editor: None,
82 hovered_descendant_ix: None,
83 selected_descendant_ix: None,
84 focus_handle: cx.focus_handle(),
85 };
86
87 this.workspace_updated(active_item, window, cx);
88 cx.observe_in(
89 &workspace_handle.upgrade().unwrap(),
90 window,
91 |this, workspace, window, cx| {
92 this.workspace_updated(workspace.read(cx).active_item(cx), window, cx);
93 },
94 )
95 .detach();
96
97 this
98 }
99
100 fn workspace_updated(
101 &mut self,
102 active_item: Option<Box<dyn ItemHandle>>,
103 window: &mut Window,
104 cx: &mut Context<Self>,
105 ) {
106 if let Some(item) = active_item
107 && item.item_id() != cx.entity_id()
108 && let Some(editor) = item.act_as::<Editor>(cx) {
109 self.set_editor(editor, window, cx);
110 }
111 }
112
113 fn set_editor(&mut self, editor: Entity<Editor>, window: &mut Window, cx: &mut Context<Self>) {
114 if let Some(state) = &self.editor {
115 if state.editor == editor {
116 return;
117 }
118 editor.update(cx, |editor, cx| {
119 editor.clear_background_highlights::<Self>(cx)
120 });
121 }
122
123 let subscription = cx.subscribe_in(&editor, window, |this, _, event, window, cx| {
124 let did_reparse = match event {
125 editor::EditorEvent::Reparsed(_) => true,
126 editor::EditorEvent::SelectionsChanged { .. } => false,
127 _ => return,
128 };
129 this.editor_updated(did_reparse, window, cx);
130 });
131
132 self.editor = Some(EditorState {
133 editor,
134 _subscription: subscription,
135 active_buffer: None,
136 });
137 self.editor_updated(true, window, cx);
138 }
139
140 fn editor_updated(
141 &mut self,
142 did_reparse: bool,
143 window: &mut Window,
144 cx: &mut Context<Self>,
145 ) -> Option<()> {
146 // Find which excerpt the cursor is in, and the position within that excerpted buffer.
147 let editor_state = self.editor.as_mut()?;
148 let snapshot = editor_state
149 .editor
150 .update(cx, |editor, cx| editor.snapshot(window, cx));
151 let (buffer, range, excerpt_id) = editor_state.editor.update(cx, |editor, cx| {
152 let selection_range = editor.selections.last::<usize>(cx).range();
153 let multi_buffer = editor.buffer().read(cx);
154 let (buffer, range, excerpt_id) = snapshot
155 .buffer_snapshot
156 .range_to_buffer_ranges(selection_range)
157 .pop()?;
158 let buffer = multi_buffer.buffer(buffer.remote_id()).unwrap().clone();
159 Some((buffer, range, excerpt_id))
160 })?;
161
162 // If the cursor has moved into a different excerpt, retrieve a new syntax layer
163 // from that buffer.
164 let buffer_state = editor_state
165 .active_buffer
166 .get_or_insert_with(|| BufferState {
167 buffer: buffer.clone(),
168 excerpt_id,
169 active_layer: None,
170 });
171 let mut prev_layer = None;
172 if did_reparse {
173 prev_layer = buffer_state.active_layer.take();
174 }
175 if buffer_state.buffer != buffer || buffer_state.excerpt_id != excerpt_id {
176 buffer_state.buffer = buffer.clone();
177 buffer_state.excerpt_id = excerpt_id;
178 buffer_state.active_layer = None;
179 }
180
181 let layer = match &mut buffer_state.active_layer {
182 Some(layer) => layer,
183 None => {
184 let snapshot = buffer.read(cx).snapshot();
185 let layer = if let Some(prev_layer) = prev_layer {
186 let prev_range = prev_layer.node().byte_range();
187 snapshot
188 .syntax_layers()
189 .filter(|layer| layer.language == &prev_layer.language)
190 .min_by_key(|layer| {
191 let range = layer.node().byte_range();
192 ((range.start as i64) - (prev_range.start as i64)).abs()
193 + ((range.end as i64) - (prev_range.end as i64)).abs()
194 })?
195 } else {
196 snapshot.syntax_layers().next()?
197 };
198 buffer_state.active_layer.insert(layer.to_owned())
199 }
200 };
201
202 // Within the active layer, find the syntax node under the cursor,
203 // and scroll to it.
204 let mut cursor = layer.node().walk();
205 while cursor.goto_first_child_for_byte(range.start).is_some() {
206 if !range.is_empty() && cursor.node().end_byte() == range.start {
207 cursor.goto_next_sibling();
208 }
209 }
210
211 // Ascend to the smallest ancestor that contains the range.
212 loop {
213 let node_range = cursor.node().byte_range();
214 if node_range.start <= range.start && node_range.end >= range.end {
215 break;
216 }
217 if !cursor.goto_parent() {
218 break;
219 }
220 }
221
222 let descendant_ix = cursor.descendant_index();
223 self.selected_descendant_ix = Some(descendant_ix);
224 self.list_scroll_handle
225 .scroll_to_item(descendant_ix, ScrollStrategy::Center);
226
227 cx.notify();
228 Some(())
229 }
230
231 fn update_editor_with_range_for_descendant_ix(
232 &self,
233 descendant_ix: usize,
234 window: &mut Window,
235 cx: &mut Context<Self>,
236 mut f: impl FnMut(&mut Editor, Range<Anchor>, &mut Window, &mut Context<Editor>),
237 ) -> Option<()> {
238 let editor_state = self.editor.as_ref()?;
239 let buffer_state = editor_state.active_buffer.as_ref()?;
240 let layer = buffer_state.active_layer.as_ref()?;
241
242 // Find the node.
243 let mut cursor = layer.node().walk();
244 cursor.goto_descendant(descendant_ix);
245 let node = cursor.node();
246 let range = node.byte_range();
247
248 // Build a text anchor range.
249 let buffer = buffer_state.buffer.read(cx);
250 let range = buffer.anchor_before(range.start)..buffer.anchor_after(range.end);
251
252 // Build a multibuffer anchor range.
253 let multibuffer = editor_state.editor.read(cx).buffer();
254 let multibuffer = multibuffer.read(cx).snapshot(cx);
255 let excerpt_id = buffer_state.excerpt_id;
256 let range = multibuffer
257 .anchor_in_excerpt(excerpt_id, range.start)
258 .unwrap()
259 ..multibuffer
260 .anchor_in_excerpt(excerpt_id, range.end)
261 .unwrap();
262
263 // Update the editor with the anchor range.
264 editor_state.editor.update(cx, |editor, cx| {
265 f(editor, range, window, cx);
266 });
267 Some(())
268 }
269
270 fn render_node(cursor: &TreeCursor, depth: u32, selected: bool, cx: &App) -> Div {
271 let colors = cx.theme().colors();
272 let mut row = h_flex();
273 if let Some(field_name) = cursor.field_name() {
274 row = row.children([Label::new(field_name).color(Color::Info), Label::new(": ")]);
275 }
276
277 let node = cursor.node();
278 row.child(if node.is_named() {
279 Label::new(node.kind()).color(Color::Default)
280 } else {
281 Label::new(format!("\"{}\"", node.kind())).color(Color::Created)
282 })
283 .child(
284 div()
285 .child(Label::new(format_node_range(node)).color(Color::Muted))
286 .pl_1(),
287 )
288 .text_bg(if selected {
289 colors.element_selected
290 } else {
291 Hsla::default()
292 })
293 .pl(rems(depth as f32))
294 .hover(|style| style.bg(colors.element_hover))
295 }
296}
297
298impl Render for SyntaxTreeView {
299 fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
300 let mut rendered = div().flex_1().bg(cx.theme().colors().editor_background);
301
302 if let Some(layer) = self
303 .editor
304 .as_ref()
305 .and_then(|editor| editor.active_buffer.as_ref())
306 .and_then(|buffer| buffer.active_layer.as_ref())
307 {
308 let layer = layer.clone();
309 rendered = rendered.child(uniform_list(
310 "SyntaxTreeView",
311 layer.node().descendant_count(),
312 cx.processor(move |this, range: Range<usize>, _, cx| {
313 let mut items = Vec::new();
314 let mut cursor = layer.node().walk();
315 let mut descendant_ix = range.start;
316 cursor.goto_descendant(descendant_ix);
317 let mut depth = cursor.depth();
318 let mut visited_children = false;
319 while descendant_ix < range.end {
320 if visited_children {
321 if cursor.goto_next_sibling() {
322 visited_children = false;
323 } else if cursor.goto_parent() {
324 depth -= 1;
325 } else {
326 break;
327 }
328 } else {
329 items.push(
330 Self::render_node(
331 &cursor,
332 depth,
333 Some(descendant_ix) == this.selected_descendant_ix,
334 cx,
335 )
336 .on_mouse_down(
337 MouseButton::Left,
338 cx.listener(move |tree_view, _: &MouseDownEvent, window, cx| {
339 tree_view.update_editor_with_range_for_descendant_ix(
340 descendant_ix,
341 window, cx,
342 |editor, mut range, window, cx| {
343 // Put the cursor at the beginning of the node.
344 mem::swap(&mut range.start, &mut range.end);
345
346 editor.change_selections(
347 SelectionEffects::scroll(Autoscroll::newest()),
348 window, cx,
349 |selections| {
350 selections.select_ranges(vec![range]);
351 },
352 );
353 },
354 );
355 }),
356 )
357 .on_mouse_move(cx.listener(
358 move |tree_view, _: &MouseMoveEvent, window, cx| {
359 if tree_view.hovered_descendant_ix != Some(descendant_ix) {
360 tree_view.hovered_descendant_ix = Some(descendant_ix);
361 tree_view.update_editor_with_range_for_descendant_ix(descendant_ix, window, cx, |editor, range, _, cx| {
362 editor.clear_background_highlights::<Self>( cx);
363 editor.highlight_background::<Self>(
364 &[range],
365 |theme| theme.colors().editor_document_highlight_write_background,
366 cx,
367 );
368 });
369 cx.notify();
370 }
371 },
372 )),
373 );
374 descendant_ix += 1;
375 if cursor.goto_first_child() {
376 depth += 1;
377 } else {
378 visited_children = true;
379 }
380 }
381 }
382 items
383 }),
384 )
385 .size_full()
386 .track_scroll(self.list_scroll_handle.clone())
387 .text_bg(cx.theme().colors().background).into_any_element());
388 }
389
390 rendered
391 }
392}
393
394impl EventEmitter<()> for SyntaxTreeView {}
395
396impl Focusable for SyntaxTreeView {
397 fn focus_handle(&self, _: &App) -> gpui::FocusHandle {
398 self.focus_handle.clone()
399 }
400}
401
402impl Item for SyntaxTreeView {
403 type Event = ();
404
405 fn to_item_events(_: &Self::Event, _: impl FnMut(workspace::item::ItemEvent)) {}
406
407 fn tab_content_text(&self, _detail: usize, _cx: &App) -> SharedString {
408 "Syntax Tree".into()
409 }
410
411 fn telemetry_event_text(&self) -> Option<&'static str> {
412 None
413 }
414
415 fn clone_on_split(
416 &self,
417 _: Option<workspace::WorkspaceId>,
418 window: &mut Window,
419 cx: &mut Context<Self>,
420 ) -> Option<Entity<Self>>
421 where
422 Self: Sized,
423 {
424 Some(cx.new(|cx| {
425 let mut clone = Self::new(self.workspace_handle.clone(), None, window, cx);
426 if let Some(editor) = &self.editor {
427 clone.set_editor(editor.editor.clone(), window, cx)
428 }
429 clone
430 }))
431 }
432}
433
434impl Default for SyntaxTreeToolbarItemView {
435 fn default() -> Self {
436 Self::new()
437 }
438}
439
440impl SyntaxTreeToolbarItemView {
441 pub fn new() -> Self {
442 Self {
443 tree_view: None,
444 subscription: None,
445 }
446 }
447
448 fn render_menu(&mut self, cx: &mut Context<Self>) -> Option<PopoverMenu<ContextMenu>> {
449 let tree_view = self.tree_view.as_ref()?;
450 let tree_view = tree_view.read(cx);
451
452 let editor_state = tree_view.editor.as_ref()?;
453 let buffer_state = editor_state.active_buffer.as_ref()?;
454 let active_layer = buffer_state.active_layer.clone()?;
455 let active_buffer = buffer_state.buffer.read(cx).snapshot();
456
457 let view = cx.entity();
458 Some(
459 PopoverMenu::new("Syntax Tree")
460 .trigger(Self::render_header(&active_layer))
461 .menu(move |window, cx| {
462 ContextMenu::build(window, cx, |mut menu, window, _| {
463 for (layer_ix, layer) in active_buffer.syntax_layers().enumerate() {
464 menu = menu.entry(
465 format!(
466 "{} {}",
467 layer.language.name(),
468 format_node_range(layer.node())
469 ),
470 None,
471 window.handler_for(&view, move |view, window, cx| {
472 view.select_layer(layer_ix, window, cx);
473 }),
474 );
475 }
476 menu
477 })
478 .into()
479 }),
480 )
481 }
482
483 fn select_layer(
484 &mut self,
485 layer_ix: usize,
486 window: &mut Window,
487 cx: &mut Context<Self>,
488 ) -> Option<()> {
489 let tree_view = self.tree_view.as_ref()?;
490 tree_view.update(cx, |view, cx| {
491 let editor_state = view.editor.as_mut()?;
492 let buffer_state = editor_state.active_buffer.as_mut()?;
493 let snapshot = buffer_state.buffer.read(cx).snapshot();
494 let layer = snapshot.syntax_layers().nth(layer_ix)?;
495 buffer_state.active_layer = Some(layer.to_owned());
496 view.selected_descendant_ix = None;
497 cx.notify();
498 view.focus_handle.focus(window);
499 Some(())
500 })
501 }
502
503 fn render_header(active_layer: &OwnedSyntaxLayer) -> ButtonLike {
504 ButtonLike::new("syntax tree header")
505 .child(Label::new(active_layer.language.name()))
506 .child(Label::new(format_node_range(active_layer.node())))
507 }
508}
509
510fn format_node_range(node: Node) -> String {
511 let start = node.start_position();
512 let end = node.end_position();
513 format!(
514 "[{}:{} - {}:{}]",
515 start.row + 1,
516 start.column + 1,
517 end.row + 1,
518 end.column + 1,
519 )
520}
521
522impl Render for SyntaxTreeToolbarItemView {
523 fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
524 self.render_menu(cx)
525 .unwrap_or_else(|| PopoverMenu::new("Empty Syntax Tree"))
526 }
527}
528
529impl EventEmitter<ToolbarItemEvent> for SyntaxTreeToolbarItemView {}
530
531impl ToolbarItemView for SyntaxTreeToolbarItemView {
532 fn set_active_pane_item(
533 &mut self,
534 active_pane_item: Option<&dyn ItemHandle>,
535 window: &mut Window,
536 cx: &mut Context<Self>,
537 ) -> ToolbarItemLocation {
538 if let Some(item) = active_pane_item
539 && let Some(view) = item.downcast::<SyntaxTreeView>() {
540 self.tree_view = Some(view.clone());
541 self.subscription = Some(cx.observe_in(&view, window, |_, _, _, cx| cx.notify()));
542 return ToolbarItemLocation::PrimaryLeft;
543 }
544 self.tree_view = None;
545 self.subscription = None;
546 ToolbarItemLocation::Hidden
547 }
548}