1use collections::BTreeMap;
2use gpui::HighlightStyle;
3use language::Chunk;
4use multi_buffer::{MultiBufferChunks, MultiBufferOffset, MultiBufferSnapshot, ToOffset as _};
5use std::{
6 cmp,
7 iter::{self, Peekable},
8 ops::Range,
9 vec,
10};
11
12use crate::display_map::{HighlightKey, TextHighlights};
13
14pub struct CustomHighlightsChunks<'a> {
15 buffer_chunks: MultiBufferChunks<'a>,
16 buffer_chunk: Option<Chunk<'a>>,
17 offset: MultiBufferOffset,
18 multibuffer_snapshot: &'a MultiBufferSnapshot,
19
20 highlight_endpoints: Peekable<vec::IntoIter<HighlightEndpoint>>,
21 active_highlights: BTreeMap<HighlightKey, HighlightStyle>,
22 text_highlights: Option<&'a TextHighlights>,
23}
24
25#[derive(Debug, Copy, Clone, Eq, PartialEq)]
26struct HighlightEndpoint {
27 offset: MultiBufferOffset,
28 tag: HighlightKey,
29 style: Option<HighlightStyle>,
30}
31
32impl<'a> CustomHighlightsChunks<'a> {
33 #[ztracing::instrument(skip_all)]
34 pub fn new(
35 range: Range<MultiBufferOffset>,
36 language_aware: bool,
37 text_highlights: Option<&'a TextHighlights>,
38 multibuffer_snapshot: &'a MultiBufferSnapshot,
39 ) -> Self {
40 Self {
41 buffer_chunks: multibuffer_snapshot.chunks(range.clone(), language_aware),
42 buffer_chunk: None,
43 offset: range.start,
44 text_highlights,
45 highlight_endpoints: create_highlight_endpoints(
46 &range,
47 text_highlights,
48 multibuffer_snapshot,
49 ),
50 active_highlights: Default::default(),
51 multibuffer_snapshot,
52 }
53 }
54
55 #[ztracing::instrument(skip_all)]
56 pub fn seek(&mut self, new_range: Range<MultiBufferOffset>) {
57 self.highlight_endpoints =
58 create_highlight_endpoints(&new_range, self.text_highlights, self.multibuffer_snapshot);
59 self.offset = new_range.start;
60 self.buffer_chunks.seek(new_range);
61 self.buffer_chunk.take();
62 self.active_highlights.clear()
63 }
64}
65
66fn create_highlight_endpoints(
67 range: &Range<MultiBufferOffset>,
68 text_highlights: Option<&TextHighlights>,
69 buffer: &MultiBufferSnapshot,
70) -> iter::Peekable<vec::IntoIter<HighlightEndpoint>> {
71 let mut highlight_endpoints = Vec::new();
72 if let Some(text_highlights) = text_highlights {
73 let start = buffer.anchor_after(range.start);
74 let end = buffer.anchor_after(range.end);
75 for (&tag, text_highlights) in text_highlights.iter() {
76 let style = text_highlights.0;
77 let ranges = &text_highlights.1;
78
79 let start_ix = ranges
80 .binary_search_by(|probe| probe.end.cmp(&start, buffer).then(cmp::Ordering::Less))
81 .unwrap_or_else(|i| i);
82
83 for range in &ranges[start_ix..] {
84 if range.start.cmp(&end, buffer).is_ge() {
85 break;
86 }
87
88 let start = range.start.to_offset(buffer);
89 let end = range.end.to_offset(buffer);
90 if start == end {
91 continue;
92 }
93 highlight_endpoints.push(HighlightEndpoint {
94 offset: start,
95 tag,
96 style: Some(style),
97 });
98 highlight_endpoints.push(HighlightEndpoint {
99 offset: end,
100 tag,
101 style: None,
102 });
103 }
104 }
105 highlight_endpoints.sort();
106 }
107 highlight_endpoints.into_iter().peekable()
108}
109
110impl<'a> Iterator for CustomHighlightsChunks<'a> {
111 type Item = Chunk<'a>;
112
113 #[ztracing::instrument(skip_all)]
114 fn next(&mut self) -> Option<Self::Item> {
115 let mut next_highlight_endpoint = MultiBufferOffset(usize::MAX);
116 while let Some(endpoint) = self.highlight_endpoints.peek().copied() {
117 if endpoint.offset <= self.offset {
118 if let Some(style) = endpoint.style {
119 self.active_highlights.insert(endpoint.tag, style);
120 } else {
121 self.active_highlights.remove(&endpoint.tag);
122 }
123 self.highlight_endpoints.next();
124 } else {
125 next_highlight_endpoint = endpoint.offset;
126 break;
127 }
128 }
129
130 let chunk = match &mut self.buffer_chunk {
131 Some(it) => it,
132 slot => slot.insert(self.buffer_chunks.next()?),
133 };
134 while chunk.text.is_empty() {
135 *chunk = self.buffer_chunks.next()?;
136 }
137
138 let split_idx = chunk.text.len().min(next_highlight_endpoint - self.offset);
139 let (prefix, suffix) = chunk.text.split_at(split_idx);
140 self.offset += prefix.len();
141
142 let mask = 1u128.unbounded_shl(split_idx as u32).wrapping_sub(1);
143 let chars = chunk.chars & mask;
144 let tabs = chunk.tabs & mask;
145 let mut prefix = Chunk {
146 text: prefix,
147 chars,
148 tabs,
149 ..chunk.clone()
150 };
151
152 chunk.chars = chunk.chars.unbounded_shr(split_idx as u32);
153 chunk.tabs = chunk.tabs.unbounded_shr(split_idx as u32);
154 chunk.text = suffix;
155 if !self.active_highlights.is_empty() {
156 prefix.highlight_style = self
157 .active_highlights
158 .values()
159 .copied()
160 .reduce(|acc, active_highlight| acc.highlight(active_highlight));
161 }
162 Some(prefix)
163 }
164}
165
166impl PartialOrd for HighlightEndpoint {
167 fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
168 Some(self.cmp(other))
169 }
170}
171
172impl Ord for HighlightEndpoint {
173 fn cmp(&self, other: &Self) -> cmp::Ordering {
174 self.offset
175 .cmp(&other.offset)
176 .then_with(|| self.style.is_some().cmp(&other.style.is_some()))
177 }
178}
179
180#[cfg(test)]
181mod tests {
182 use std::{any::TypeId, sync::Arc};
183
184 use super::*;
185 use crate::MultiBuffer;
186 use gpui::App;
187 use rand::prelude::*;
188 use util::RandomCharIter;
189
190 #[gpui::test(iterations = 100)]
191 fn test_random_chunk_bitmaps(cx: &mut App, mut rng: StdRng) {
192 // Generate random buffer using existing test infrastructure
193 let len = rng.random_range(10..10000);
194 let buffer = if rng.random() {
195 let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
196 MultiBuffer::build_simple(&text, cx)
197 } else {
198 MultiBuffer::build_random(&mut rng, cx)
199 };
200
201 let buffer_snapshot = buffer.read(cx).snapshot(cx);
202
203 // Create random highlights
204 let mut highlights = sum_tree::TreeMap::default();
205 let highlight_count = rng.random_range(1..10);
206
207 for _i in 0..highlight_count {
208 let style = HighlightStyle {
209 color: Some(gpui::Hsla {
210 h: rng.random::<f32>(),
211 s: rng.random::<f32>(),
212 l: rng.random::<f32>(),
213 a: 1.0,
214 }),
215 ..Default::default()
216 };
217
218 let mut ranges = Vec::new();
219 let range_count = rng.random_range(1..10);
220 let text = buffer_snapshot.text();
221 for _ in 0..range_count {
222 if buffer_snapshot.len() == MultiBufferOffset(0) {
223 continue;
224 }
225
226 let mut start = rng.random_range(
227 MultiBufferOffset(0)..=buffer_snapshot.len().saturating_sub_usize(10),
228 );
229
230 while !text.is_char_boundary(start.0) {
231 start = start.saturating_sub_usize(1);
232 }
233
234 let end_end = buffer_snapshot.len().min(start + 100usize);
235 let mut end = rng.random_range(start..=end_end);
236 while !text.is_char_boundary(end.0) {
237 end = end.saturating_sub_usize(1);
238 }
239
240 if start < end {
241 start = end;
242 }
243 let start_anchor = buffer_snapshot.anchor_before(start);
244 let end_anchor = buffer_snapshot.anchor_after(end);
245 ranges.push(start_anchor..end_anchor);
246 }
247
248 let type_id = TypeId::of::<()>(); // Simple type ID for testing
249 highlights.insert(HighlightKey::Type(type_id), Arc::new((style, ranges)));
250 }
251
252 // Get all chunks and verify their bitmaps
253 let chunks = CustomHighlightsChunks::new(
254 MultiBufferOffset(0)..buffer_snapshot.len(),
255 false,
256 None,
257 &buffer_snapshot,
258 );
259
260 for chunk in chunks {
261 let chunk_text = chunk.text;
262 let chars_bitmap = chunk.chars;
263 let tabs_bitmap = chunk.tabs;
264
265 // Check empty chunks have empty bitmaps
266 if chunk_text.is_empty() {
267 assert_eq!(
268 chars_bitmap, 0,
269 "Empty chunk should have empty chars bitmap"
270 );
271 assert_eq!(tabs_bitmap, 0, "Empty chunk should have empty tabs bitmap");
272 continue;
273 }
274
275 // Verify that chunk text doesn't exceed 128 bytes
276 assert!(
277 chunk_text.len() <= 128,
278 "Chunk text length {} exceeds 128 bytes",
279 chunk_text.len()
280 );
281
282 // Verify chars bitmap
283 let char_indices = chunk_text
284 .char_indices()
285 .map(|(i, _)| i)
286 .collect::<Vec<_>>();
287
288 for byte_idx in 0..chunk_text.len() {
289 let should_have_bit = char_indices.contains(&byte_idx);
290 let has_bit = chars_bitmap & (1 << byte_idx) != 0;
291
292 if has_bit != should_have_bit {
293 eprintln!("Chunk text bytes: {:?}", chunk_text.as_bytes());
294 eprintln!("Char indices: {:?}", char_indices);
295 eprintln!("Chars bitmap: {:#b}", chars_bitmap);
296 assert_eq!(
297 has_bit, should_have_bit,
298 "Chars bitmap mismatch at byte index {} in chunk {:?}. Expected bit: {}, Got bit: {}",
299 byte_idx, chunk_text, should_have_bit, has_bit
300 );
301 }
302 }
303
304 // Verify tabs bitmap
305 for (byte_idx, byte) in chunk_text.bytes().enumerate() {
306 let is_tab = byte == b'\t';
307 let has_bit = tabs_bitmap & (1 << byte_idx) != 0;
308
309 if has_bit != is_tab {
310 eprintln!("Chunk text bytes: {:?}", chunk_text.as_bytes());
311 eprintln!("Tabs bitmap: {:#b}", tabs_bitmap);
312 assert_eq!(
313 has_bit, is_tab,
314 "Tabs bitmap mismatch at byte index {} in chunk {:?}. Byte: {:?}, Expected bit: {}, Got bit: {}",
315 byte_idx, chunk_text, byte as char, is_tab, has_bit
316 );
317 }
318 }
319 }
320 }
321}