1use editor::{scroll::Autoscroll, Anchor, Editor, ExcerptId};
2use gpui::{
3 actions, div, rems, uniform_list, AppContext, Div, EventEmitter, FocusHandle, FocusableView,
4 Hsla, InteractiveElement, IntoElement, Model, MouseButton, MouseDownEvent, MouseMoveEvent,
5 ParentElement, Render, ScrollStrategy, SharedString, Styled, UniformListScrollHandle, View,
6 ViewContext, VisualContext, WeakView, WindowContext,
7};
8use language::{Buffer, OwnedSyntaxLayer};
9use std::{mem, ops::Range};
10use theme::ActiveTheme;
11use tree_sitter::{Node, TreeCursor};
12use ui::{h_flex, ButtonLike, Color, ContextMenu, Label, LabelCommon, PopoverMenu};
13use workspace::{
14 item::{Item, ItemHandle},
15 SplitDirection, ToolbarItemEvent, ToolbarItemLocation, ToolbarItemView, Workspace,
16};
17
18actions!(debug, [OpenSyntaxTreeView]);
19
20pub fn init(cx: &mut AppContext) {
21 cx.observe_new_views(|workspace: &mut Workspace, _| {
22 workspace.register_action(|workspace, _: &OpenSyntaxTreeView, cx| {
23 let active_item = workspace.active_item(cx);
24 let workspace_handle = workspace.weak_handle();
25 let syntax_tree_view =
26 cx.new_view(|cx| SyntaxTreeView::new(workspace_handle, active_item, cx));
27 workspace.split_item(SplitDirection::Right, Box::new(syntax_tree_view), cx)
28 });
29 })
30 .detach();
31}
32
33pub struct SyntaxTreeView {
34 workspace_handle: WeakView<Workspace>,
35 editor: Option<EditorState>,
36 list_scroll_handle: UniformListScrollHandle,
37 selected_descendant_ix: Option<usize>,
38 hovered_descendant_ix: Option<usize>,
39 focus_handle: FocusHandle,
40}
41
42pub struct SyntaxTreeToolbarItemView {
43 tree_view: Option<View<SyntaxTreeView>>,
44 subscription: Option<gpui::Subscription>,
45}
46
47struct EditorState {
48 editor: View<Editor>,
49 active_buffer: Option<BufferState>,
50 _subscription: gpui::Subscription,
51}
52
53#[derive(Clone)]
54struct BufferState {
55 buffer: Model<Buffer>,
56 excerpt_id: ExcerptId,
57 active_layer: Option<OwnedSyntaxLayer>,
58}
59
60impl SyntaxTreeView {
61 pub fn new(
62 workspace_handle: WeakView<Workspace>,
63 active_item: Option<Box<dyn ItemHandle>>,
64 cx: &mut ViewContext<Self>,
65 ) -> Self {
66 let mut this = Self {
67 workspace_handle: workspace_handle.clone(),
68 list_scroll_handle: UniformListScrollHandle::new(),
69 editor: None,
70 hovered_descendant_ix: None,
71 selected_descendant_ix: None,
72 focus_handle: cx.focus_handle(),
73 };
74
75 this.workspace_updated(active_item, cx);
76 cx.observe(
77 &workspace_handle.upgrade().unwrap(),
78 |this, workspace, cx| {
79 this.workspace_updated(workspace.read(cx).active_item(cx), cx);
80 },
81 )
82 .detach();
83
84 this
85 }
86
87 fn workspace_updated(
88 &mut self,
89 active_item: Option<Box<dyn ItemHandle>>,
90 cx: &mut ViewContext<Self>,
91 ) {
92 if let Some(item) = active_item {
93 if item.item_id() != cx.entity_id() {
94 if let Some(editor) = item.act_as::<Editor>(cx) {
95 self.set_editor(editor, cx);
96 }
97 }
98 }
99 }
100
101 fn set_editor(&mut self, editor: View<Editor>, cx: &mut ViewContext<Self>) {
102 if let Some(state) = &self.editor {
103 if state.editor == editor {
104 return;
105 }
106 editor.update(cx, |editor, cx| {
107 editor.clear_background_highlights::<Self>(cx)
108 });
109 }
110
111 let subscription = cx.subscribe(&editor, |this, _, event, cx| {
112 let did_reparse = match event {
113 editor::EditorEvent::Reparsed(_) => true,
114 editor::EditorEvent::SelectionsChanged { .. } => false,
115 _ => return,
116 };
117 this.editor_updated(did_reparse, cx);
118 });
119
120 self.editor = Some(EditorState {
121 editor,
122 _subscription: subscription,
123 active_buffer: None,
124 });
125 self.editor_updated(true, cx);
126 }
127
128 fn editor_updated(&mut self, did_reparse: bool, cx: &mut ViewContext<Self>) -> Option<()> {
129 // Find which excerpt the cursor is in, and the position within that excerpted buffer.
130 let editor_state = self.editor.as_mut()?;
131 let (buffer, range, excerpt_id) = editor_state.editor.update(cx, |editor, cx| {
132 let selection_range = editor.selections.last::<usize>(cx).range();
133 editor
134 .buffer()
135 .read(cx)
136 .range_to_buffer_ranges(selection_range, cx)
137 .pop()
138 })?;
139
140 // If the cursor has moved into a different excerpt, retrieve a new syntax layer
141 // from that buffer.
142 let buffer_state = editor_state
143 .active_buffer
144 .get_or_insert_with(|| BufferState {
145 buffer: buffer.clone(),
146 excerpt_id,
147 active_layer: None,
148 });
149 let mut prev_layer = None;
150 if did_reparse {
151 prev_layer = buffer_state.active_layer.take();
152 }
153 if buffer_state.buffer != buffer || buffer_state.excerpt_id != excerpt_id {
154 buffer_state.buffer = buffer.clone();
155 buffer_state.excerpt_id = excerpt_id;
156 buffer_state.active_layer = None;
157 }
158
159 let layer = match &mut buffer_state.active_layer {
160 Some(layer) => layer,
161 None => {
162 let snapshot = buffer.read(cx).snapshot();
163 let layer = if let Some(prev_layer) = prev_layer {
164 let prev_range = prev_layer.node().byte_range();
165 snapshot
166 .syntax_layers()
167 .filter(|layer| layer.language == &prev_layer.language)
168 .min_by_key(|layer| {
169 let range = layer.node().byte_range();
170 ((range.start as i64) - (prev_range.start as i64)).abs()
171 + ((range.end as i64) - (prev_range.end as i64)).abs()
172 })?
173 } else {
174 snapshot.syntax_layers().next()?
175 };
176 buffer_state.active_layer.insert(layer.to_owned())
177 }
178 };
179
180 // Within the active layer, find the syntax node under the cursor,
181 // and scroll to it.
182 let mut cursor = layer.node().walk();
183 while cursor.goto_first_child_for_byte(range.start).is_some() {
184 if !range.is_empty() && cursor.node().end_byte() == range.start {
185 cursor.goto_next_sibling();
186 }
187 }
188
189 // Ascend to the smallest ancestor that contains the range.
190 loop {
191 let node_range = cursor.node().byte_range();
192 if node_range.start <= range.start && node_range.end >= range.end {
193 break;
194 }
195 if !cursor.goto_parent() {
196 break;
197 }
198 }
199
200 let descendant_ix = cursor.descendant_index();
201 self.selected_descendant_ix = Some(descendant_ix);
202 self.list_scroll_handle
203 .scroll_to_item(descendant_ix, ScrollStrategy::Center);
204
205 cx.notify();
206 Some(())
207 }
208
209 fn update_editor_with_range_for_descendant_ix(
210 &self,
211 descendant_ix: usize,
212 cx: &mut ViewContext<Self>,
213 mut f: impl FnMut(&mut Editor, Range<Anchor>, &mut ViewContext<Editor>),
214 ) -> Option<()> {
215 let editor_state = self.editor.as_ref()?;
216 let buffer_state = editor_state.active_buffer.as_ref()?;
217 let layer = buffer_state.active_layer.as_ref()?;
218
219 // Find the node.
220 let mut cursor = layer.node().walk();
221 cursor.goto_descendant(descendant_ix);
222 let node = cursor.node();
223 let range = node.byte_range();
224
225 // Build a text anchor range.
226 let buffer = buffer_state.buffer.read(cx);
227 let range = buffer.anchor_before(range.start)..buffer.anchor_after(range.end);
228
229 // Build a multibuffer anchor range.
230 let multibuffer = editor_state.editor.read(cx).buffer();
231 let multibuffer = multibuffer.read(cx).snapshot(cx);
232 let excerpt_id = buffer_state.excerpt_id;
233 let range = multibuffer
234 .anchor_in_excerpt(excerpt_id, range.start)
235 .unwrap()
236 ..multibuffer
237 .anchor_in_excerpt(excerpt_id, range.end)
238 .unwrap();
239
240 // Update the editor with the anchor range.
241 editor_state.editor.update(cx, |editor, cx| {
242 f(editor, range, cx);
243 });
244 Some(())
245 }
246
247 fn render_node(cursor: &TreeCursor, depth: u32, selected: bool, cx: &AppContext) -> Div {
248 let colors = cx.theme().colors();
249 let mut row = h_flex();
250 if let Some(field_name) = cursor.field_name() {
251 row = row.children([Label::new(field_name).color(Color::Info), Label::new(": ")]);
252 }
253
254 let node = cursor.node();
255 row.child(if node.is_named() {
256 Label::new(node.kind()).color(Color::Default)
257 } else {
258 Label::new(format!("\"{}\"", node.kind())).color(Color::Created)
259 })
260 .child(
261 div()
262 .child(Label::new(format_node_range(node)).color(Color::Muted))
263 .pl_1(),
264 )
265 .text_bg(if selected {
266 colors.element_selected
267 } else {
268 Hsla::default()
269 })
270 .pl(rems(depth as f32))
271 .hover(|style| style.bg(colors.element_hover))
272 }
273}
274
275impl Render for SyntaxTreeView {
276 fn render(&mut self, cx: &mut ViewContext<Self>) -> impl IntoElement {
277 let mut rendered = div().flex_1();
278
279 if let Some(layer) = self
280 .editor
281 .as_ref()
282 .and_then(|editor| editor.active_buffer.as_ref())
283 .and_then(|buffer| buffer.active_layer.as_ref())
284 {
285 let layer = layer.clone();
286 rendered = rendered.child(uniform_list(
287 cx.view().clone(),
288 "SyntaxTreeView",
289 layer.node().descendant_count(),
290 move |this, range, cx| {
291 let mut items = Vec::new();
292 let mut cursor = layer.node().walk();
293 let mut descendant_ix = range.start;
294 cursor.goto_descendant(descendant_ix);
295 let mut depth = cursor.depth();
296 let mut visited_children = false;
297 while descendant_ix < range.end {
298 if visited_children {
299 if cursor.goto_next_sibling() {
300 visited_children = false;
301 } else if cursor.goto_parent() {
302 depth -= 1;
303 } else {
304 break;
305 }
306 } else {
307 items.push(
308 Self::render_node(
309 &cursor,
310 depth,
311 Some(descendant_ix) == this.selected_descendant_ix,
312 cx,
313 )
314 .on_mouse_down(
315 MouseButton::Left,
316 cx.listener(move |tree_view, _: &MouseDownEvent, cx| {
317 tree_view.update_editor_with_range_for_descendant_ix(
318 descendant_ix,
319 cx,
320 |editor, mut range, cx| {
321 // Put the cursor at the beginning of the node.
322 mem::swap(&mut range.start, &mut range.end);
323
324 editor.change_selections(
325 Some(Autoscroll::newest()),
326 cx,
327 |selections| {
328 selections.select_ranges(vec![range]);
329 },
330 );
331 },
332 );
333 }),
334 )
335 .on_mouse_move(cx.listener(
336 move |tree_view, _: &MouseMoveEvent, cx| {
337 if tree_view.hovered_descendant_ix != Some(descendant_ix) {
338 tree_view.hovered_descendant_ix = Some(descendant_ix);
339 tree_view.update_editor_with_range_for_descendant_ix(descendant_ix, cx, |editor, range, cx| {
340 editor.clear_background_highlights::<Self>(cx);
341 editor.highlight_background::<Self>(
342 &[range],
343 |theme| theme.editor_document_highlight_write_background,
344 cx,
345 );
346 });
347 cx.notify();
348 }
349 },
350 )),
351 );
352 descendant_ix += 1;
353 if cursor.goto_first_child() {
354 depth += 1;
355 } else {
356 visited_children = true;
357 }
358 }
359 }
360 items
361 },
362 )
363 .size_full()
364 .track_scroll(self.list_scroll_handle.clone())
365 .text_bg(cx.theme().colors().background).into_any_element());
366 }
367
368 rendered
369 }
370}
371
372impl EventEmitter<()> for SyntaxTreeView {}
373
374impl FocusableView for SyntaxTreeView {
375 fn focus_handle(&self, _: &AppContext) -> gpui::FocusHandle {
376 self.focus_handle.clone()
377 }
378}
379
380impl Item for SyntaxTreeView {
381 type Event = ();
382
383 fn to_item_events(_: &Self::Event, _: impl FnMut(workspace::item::ItemEvent)) {}
384
385 fn tab_content_text(&self, _cx: &WindowContext) -> Option<SharedString> {
386 Some("Syntax Tree".into())
387 }
388
389 fn telemetry_event_text(&self) -> Option<&'static str> {
390 None
391 }
392
393 fn clone_on_split(
394 &self,
395 _: Option<workspace::WorkspaceId>,
396 cx: &mut ViewContext<Self>,
397 ) -> Option<View<Self>>
398 where
399 Self: Sized,
400 {
401 Some(cx.new_view(|cx| {
402 let mut clone = Self::new(self.workspace_handle.clone(), None, cx);
403 if let Some(editor) = &self.editor {
404 clone.set_editor(editor.editor.clone(), cx)
405 }
406 clone
407 }))
408 }
409}
410
411impl Default for SyntaxTreeToolbarItemView {
412 fn default() -> Self {
413 Self::new()
414 }
415}
416
417impl SyntaxTreeToolbarItemView {
418 pub fn new() -> Self {
419 Self {
420 tree_view: None,
421 subscription: None,
422 }
423 }
424
425 fn render_menu(&mut self, cx: &mut ViewContext<Self>) -> Option<PopoverMenu<ContextMenu>> {
426 let tree_view = self.tree_view.as_ref()?;
427 let tree_view = tree_view.read(cx);
428
429 let editor_state = tree_view.editor.as_ref()?;
430 let buffer_state = editor_state.active_buffer.as_ref()?;
431 let active_layer = buffer_state.active_layer.clone()?;
432 let active_buffer = buffer_state.buffer.read(cx).snapshot();
433
434 let view = cx.view().clone();
435 Some(
436 PopoverMenu::new("Syntax Tree")
437 .trigger(Self::render_header(&active_layer))
438 .menu(move |cx| {
439 ContextMenu::build(cx, |mut menu, cx| {
440 for (layer_ix, layer) in active_buffer.syntax_layers().enumerate() {
441 menu = menu.entry(
442 format!(
443 "{} {}",
444 layer.language.name(),
445 format_node_range(layer.node())
446 ),
447 None,
448 cx.handler_for(&view, move |view, cx| {
449 view.select_layer(layer_ix, cx);
450 }),
451 );
452 }
453 menu
454 })
455 .into()
456 }),
457 )
458 }
459
460 fn select_layer(&mut self, layer_ix: usize, cx: &mut ViewContext<Self>) -> Option<()> {
461 let tree_view = self.tree_view.as_ref()?;
462 tree_view.update(cx, |view, cx| {
463 let editor_state = view.editor.as_mut()?;
464 let buffer_state = editor_state.active_buffer.as_mut()?;
465 let snapshot = buffer_state.buffer.read(cx).snapshot();
466 let layer = snapshot.syntax_layers().nth(layer_ix)?;
467 buffer_state.active_layer = Some(layer.to_owned());
468 view.selected_descendant_ix = None;
469 cx.notify();
470 view.focus_handle.focus(cx);
471 Some(())
472 })
473 }
474
475 fn render_header(active_layer: &OwnedSyntaxLayer) -> ButtonLike {
476 ButtonLike::new("syntax tree header")
477 .child(Label::new(active_layer.language.name().0))
478 .child(Label::new(format_node_range(active_layer.node())))
479 }
480}
481
482fn format_node_range(node: Node) -> String {
483 let start = node.start_position();
484 let end = node.end_position();
485 format!(
486 "[{}:{} - {}:{}]",
487 start.row + 1,
488 start.column + 1,
489 end.row + 1,
490 end.column + 1,
491 )
492}
493
494impl Render for SyntaxTreeToolbarItemView {
495 fn render(&mut self, cx: &mut ViewContext<Self>) -> impl IntoElement {
496 self.render_menu(cx)
497 .unwrap_or_else(|| PopoverMenu::new("Empty Syntax Tree"))
498 }
499}
500
501impl EventEmitter<ToolbarItemEvent> for SyntaxTreeToolbarItemView {}
502
503impl ToolbarItemView for SyntaxTreeToolbarItemView {
504 fn set_active_pane_item(
505 &mut self,
506 active_pane_item: Option<&dyn ItemHandle>,
507 cx: &mut ViewContext<Self>,
508 ) -> ToolbarItemLocation {
509 if let Some(item) = active_pane_item {
510 if let Some(view) = item.downcast::<SyntaxTreeView>() {
511 self.tree_view = Some(view.clone());
512 self.subscription = Some(cx.observe(&view, |_, _, cx| cx.notify()));
513 return ToolbarItemLocation::PrimaryLeft;
514 }
515 }
516 self.tree_view = None;
517 self.subscription = None;
518 ToolbarItemLocation::Hidden
519 }
520}