1use crate::streaming_diff::{Hunk, StreamingDiff};
2use ai::completion::{CompletionProvider, CompletionRequest};
3use anyhow::Result;
4use editor::{multi_buffer, Anchor, MultiBuffer, MultiBufferSnapshot, ToOffset, ToPoint};
5use futures::{channel::mpsc, SinkExt, Stream, StreamExt};
6use gpui::{Entity, ModelContext, ModelHandle, Task};
7use language::{Rope, TransactionId};
8use std::{cmp, future, ops::Range, sync::Arc};
9
10pub enum Event {
11 Finished,
12 Undone,
13}
14
15#[derive(Clone)]
16pub enum CodegenKind {
17 Transform { range: Range<Anchor> },
18 Generate { position: Anchor },
19}
20
21pub struct Codegen {
22 provider: Arc<dyn CompletionProvider>,
23 buffer: ModelHandle<MultiBuffer>,
24 snapshot: MultiBufferSnapshot,
25 kind: CodegenKind,
26 last_equal_ranges: Vec<Range<Anchor>>,
27 transaction_id: Option<TransactionId>,
28 error: Option<anyhow::Error>,
29 generation: Task<()>,
30 idle: bool,
31 _subscription: gpui::Subscription,
32}
33
34impl Entity for Codegen {
35 type Event = Event;
36}
37
38impl Codegen {
39 pub fn new(
40 buffer: ModelHandle<MultiBuffer>,
41 kind: CodegenKind,
42 provider: Arc<dyn CompletionProvider>,
43 cx: &mut ModelContext<Self>,
44 ) -> Self {
45 let snapshot = buffer.read(cx).snapshot(cx);
46 Self {
47 provider,
48 buffer: buffer.clone(),
49 snapshot,
50 kind,
51 last_equal_ranges: Default::default(),
52 transaction_id: Default::default(),
53 error: Default::default(),
54 idle: true,
55 generation: Task::ready(()),
56 _subscription: cx.subscribe(&buffer, Self::handle_buffer_event),
57 }
58 }
59
60 fn handle_buffer_event(
61 &mut self,
62 _buffer: ModelHandle<MultiBuffer>,
63 event: &multi_buffer::Event,
64 cx: &mut ModelContext<Self>,
65 ) {
66 if let multi_buffer::Event::TransactionUndone { transaction_id } = event {
67 if self.transaction_id == Some(*transaction_id) {
68 self.transaction_id = None;
69 self.generation = Task::ready(());
70 cx.emit(Event::Undone);
71 }
72 }
73 }
74
75 pub fn range(&self) -> Range<Anchor> {
76 match &self.kind {
77 CodegenKind::Transform { range } => range.clone(),
78 CodegenKind::Generate { position } => position.bias_left(&self.snapshot)..*position,
79 }
80 }
81
82 pub fn kind(&self) -> &CodegenKind {
83 &self.kind
84 }
85
86 pub fn last_equal_ranges(&self) -> &[Range<Anchor>] {
87 &self.last_equal_ranges
88 }
89
90 pub fn idle(&self) -> bool {
91 self.idle
92 }
93
94 pub fn error(&self) -> Option<&anyhow::Error> {
95 self.error.as_ref()
96 }
97
98 pub fn start(&mut self, prompt: Box<dyn CompletionRequest>, cx: &mut ModelContext<Self>) {
99 let range = self.range();
100 let snapshot = self.snapshot.clone();
101 let selected_text = snapshot
102 .text_for_range(range.start..range.end)
103 .collect::<Rope>();
104
105 let selection_start = range.start.to_point(&snapshot);
106 let suggested_line_indent = snapshot
107 .suggested_indents(selection_start.row..selection_start.row + 1, cx)
108 .into_values()
109 .next()
110 .unwrap_or_else(|| snapshot.indent_size_for_line(selection_start.row));
111
112 let response = self.provider.complete(prompt);
113 self.generation = cx.spawn_weak(|this, mut cx| {
114 async move {
115 let generate = async {
116 let mut edit_start = range.start.to_offset(&snapshot);
117
118 let (mut hunks_tx, mut hunks_rx) = mpsc::channel(1);
119 let diff = cx.background().spawn(async move {
120 let chunks = strip_markdown_codeblock(response.await?);
121 futures::pin_mut!(chunks);
122 let mut diff = StreamingDiff::new(selected_text.to_string());
123
124 let mut new_text = String::new();
125 let mut base_indent = None;
126 let mut line_indent = None;
127 let mut first_line = true;
128
129 while let Some(chunk) = chunks.next().await {
130 let chunk = chunk?;
131
132 let mut lines = chunk.split('\n').peekable();
133 while let Some(line) = lines.next() {
134 new_text.push_str(line);
135 if line_indent.is_none() {
136 if let Some(non_whitespace_ch_ix) =
137 new_text.find(|ch: char| !ch.is_whitespace())
138 {
139 line_indent = Some(non_whitespace_ch_ix);
140 base_indent = base_indent.or(line_indent);
141
142 let line_indent = line_indent.unwrap();
143 let base_indent = base_indent.unwrap();
144 let indent_delta = line_indent as i32 - base_indent as i32;
145 let mut corrected_indent_len = cmp::max(
146 0,
147 suggested_line_indent.len as i32 + indent_delta,
148 )
149 as usize;
150 if first_line {
151 corrected_indent_len = corrected_indent_len
152 .saturating_sub(selection_start.column as usize);
153 }
154
155 let indent_char = suggested_line_indent.char();
156 let mut indent_buffer = [0; 4];
157 let indent_str =
158 indent_char.encode_utf8(&mut indent_buffer);
159 new_text.replace_range(
160 ..line_indent,
161 &indent_str.repeat(corrected_indent_len),
162 );
163 }
164 }
165
166 if line_indent.is_some() {
167 hunks_tx.send(diff.push_new(&new_text)).await?;
168 new_text.clear();
169 }
170
171 if lines.peek().is_some() {
172 hunks_tx.send(diff.push_new("\n")).await?;
173 line_indent = None;
174 first_line = false;
175 }
176 }
177 }
178 hunks_tx.send(diff.push_new(&new_text)).await?;
179 hunks_tx.send(diff.finish()).await?;
180
181 anyhow::Ok(())
182 });
183
184 while let Some(hunks) = hunks_rx.next().await {
185 let this = if let Some(this) = this.upgrade(&cx) {
186 this
187 } else {
188 break;
189 };
190
191 this.update(&mut cx, |this, cx| {
192 this.last_equal_ranges.clear();
193
194 let transaction = this.buffer.update(cx, |buffer, cx| {
195 // Avoid grouping assistant edits with user edits.
196 buffer.finalize_last_transaction(cx);
197
198 buffer.start_transaction(cx);
199 buffer.edit(
200 hunks.into_iter().filter_map(|hunk| match hunk {
201 Hunk::Insert { text } => {
202 let edit_start = snapshot.anchor_after(edit_start);
203 Some((edit_start..edit_start, text))
204 }
205 Hunk::Remove { len } => {
206 let edit_end = edit_start + len;
207 let edit_range = snapshot.anchor_after(edit_start)
208 ..snapshot.anchor_before(edit_end);
209 edit_start = edit_end;
210 Some((edit_range, String::new()))
211 }
212 Hunk::Keep { len } => {
213 let edit_end = edit_start + len;
214 let edit_range = snapshot.anchor_after(edit_start)
215 ..snapshot.anchor_before(edit_end);
216 edit_start = edit_end;
217 this.last_equal_ranges.push(edit_range);
218 None
219 }
220 }),
221 None,
222 cx,
223 );
224
225 buffer.end_transaction(cx)
226 });
227
228 if let Some(transaction) = transaction {
229 if let Some(first_transaction) = this.transaction_id {
230 // Group all assistant edits into the first transaction.
231 this.buffer.update(cx, |buffer, cx| {
232 buffer.merge_transactions(
233 transaction,
234 first_transaction,
235 cx,
236 )
237 });
238 } else {
239 this.transaction_id = Some(transaction);
240 this.buffer.update(cx, |buffer, cx| {
241 buffer.finalize_last_transaction(cx)
242 });
243 }
244 }
245
246 cx.notify();
247 });
248 }
249
250 diff.await?;
251 anyhow::Ok(())
252 };
253
254 let result = generate.await;
255 if let Some(this) = this.upgrade(&cx) {
256 this.update(&mut cx, |this, cx| {
257 this.last_equal_ranges.clear();
258 this.idle = true;
259 if let Err(error) = result {
260 this.error = Some(error);
261 }
262 cx.emit(Event::Finished);
263 cx.notify();
264 });
265 }
266 }
267 });
268 self.error.take();
269 self.idle = false;
270 cx.notify();
271 }
272
273 pub fn undo(&mut self, cx: &mut ModelContext<Self>) {
274 if let Some(transaction_id) = self.transaction_id {
275 self.buffer
276 .update(cx, |buffer, cx| buffer.undo_transaction(transaction_id, cx));
277 }
278 }
279}
280
281fn strip_markdown_codeblock(
282 stream: impl Stream<Item = Result<String>>,
283) -> impl Stream<Item = Result<String>> {
284 let mut first_line = true;
285 let mut buffer = String::new();
286 let mut starts_with_fenced_code_block = false;
287 stream.filter_map(move |chunk| {
288 let chunk = match chunk {
289 Ok(chunk) => chunk,
290 Err(err) => return future::ready(Some(Err(err))),
291 };
292 buffer.push_str(&chunk);
293
294 if first_line {
295 if buffer == "" || buffer == "`" || buffer == "``" {
296 return future::ready(None);
297 } else if buffer.starts_with("```") {
298 starts_with_fenced_code_block = true;
299 if let Some(newline_ix) = buffer.find('\n') {
300 buffer.replace_range(..newline_ix + 1, "");
301 first_line = false;
302 } else {
303 return future::ready(None);
304 }
305 }
306 }
307
308 let text = if starts_with_fenced_code_block {
309 buffer
310 .strip_suffix("\n```\n")
311 .or_else(|| buffer.strip_suffix("\n```"))
312 .or_else(|| buffer.strip_suffix("\n``"))
313 .or_else(|| buffer.strip_suffix("\n`"))
314 .or_else(|| buffer.strip_suffix('\n'))
315 .unwrap_or(&buffer)
316 } else {
317 &buffer
318 };
319
320 if text.contains('\n') {
321 first_line = false;
322 }
323
324 let remainder = buffer.split_off(text.len());
325 let result = if buffer.is_empty() {
326 None
327 } else {
328 Some(Ok(buffer.clone()))
329 };
330 buffer = remainder;
331 future::ready(result)
332 })
333}
334
335#[cfg(test)]
336mod tests {
337 use super::*;
338 use ai::providers::dummy::DummyCompletionRequest;
339 use futures::{
340 future::BoxFuture,
341 stream::{self, BoxStream},
342 };
343 use gpui::{executor::Deterministic, TestAppContext};
344 use indoc::indoc;
345 use language::{language_settings, tree_sitter_rust, Buffer, Language, LanguageConfig, Point};
346 use parking_lot::Mutex;
347 use rand::prelude::*;
348 use settings::SettingsStore;
349 use smol::future::FutureExt;
350
351 #[gpui::test(iterations = 10)]
352 async fn test_transform_autoindent(
353 cx: &mut TestAppContext,
354 mut rng: StdRng,
355 deterministic: Arc<Deterministic>,
356 ) {
357 cx.set_global(cx.read(SettingsStore::test));
358 cx.update(language_settings::init);
359
360 let text = indoc! {"
361 fn main() {
362 let x = 0;
363 for _ in 0..10 {
364 x += 1;
365 }
366 }
367 "};
368 let buffer =
369 cx.add_model(|cx| Buffer::new(0, 0, text).with_language(Arc::new(rust_lang()), cx));
370 let buffer = cx.add_model(|cx| MultiBuffer::singleton(buffer, cx));
371 let range = buffer.read_with(cx, |buffer, cx| {
372 let snapshot = buffer.snapshot(cx);
373 snapshot.anchor_before(Point::new(1, 0))..snapshot.anchor_after(Point::new(4, 5))
374 });
375 let provider = Arc::new(TestCompletionProvider::new());
376 let codegen = cx.add_model(|cx| {
377 Codegen::new(
378 buffer.clone(),
379 CodegenKind::Transform { range },
380 provider.clone(),
381 cx,
382 )
383 });
384 let request = Box::new(DummyCompletionRequest {
385 name: "test".to_string(),
386 });
387 codegen.update(cx, |codegen, cx| codegen.start(request, cx));
388
389 let mut new_text = concat!(
390 " let mut x = 0;\n",
391 " while x < 10 {\n",
392 " x += 1;\n",
393 " }",
394 );
395 while !new_text.is_empty() {
396 let max_len = cmp::min(new_text.len(), 10);
397 let len = rng.gen_range(1..=max_len);
398 let (chunk, suffix) = new_text.split_at(len);
399 provider.send_completion(chunk);
400 new_text = suffix;
401 deterministic.run_until_parked();
402 }
403 provider.finish_completion();
404 deterministic.run_until_parked();
405
406 assert_eq!(
407 buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
408 indoc! {"
409 fn main() {
410 let mut x = 0;
411 while x < 10 {
412 x += 1;
413 }
414 }
415 "}
416 );
417 }
418
419 #[gpui::test(iterations = 10)]
420 async fn test_autoindent_when_generating_past_indentation(
421 cx: &mut TestAppContext,
422 mut rng: StdRng,
423 deterministic: Arc<Deterministic>,
424 ) {
425 cx.set_global(cx.read(SettingsStore::test));
426 cx.update(language_settings::init);
427
428 let text = indoc! {"
429 fn main() {
430 le
431 }
432 "};
433 let buffer =
434 cx.add_model(|cx| Buffer::new(0, 0, text).with_language(Arc::new(rust_lang()), cx));
435 let buffer = cx.add_model(|cx| MultiBuffer::singleton(buffer, cx));
436 let position = buffer.read_with(cx, |buffer, cx| {
437 let snapshot = buffer.snapshot(cx);
438 snapshot.anchor_before(Point::new(1, 6))
439 });
440 let provider = Arc::new(TestCompletionProvider::new());
441 let codegen = cx.add_model(|cx| {
442 Codegen::new(
443 buffer.clone(),
444 CodegenKind::Generate { position },
445 provider.clone(),
446 cx,
447 )
448 });
449
450 let request = Box::new(DummyCompletionRequest {
451 name: "test".to_string(),
452 });
453 codegen.update(cx, |codegen, cx| codegen.start(request, cx));
454
455 let mut new_text = concat!(
456 "t mut x = 0;\n",
457 "while x < 10 {\n",
458 " x += 1;\n",
459 "}", //
460 );
461 while !new_text.is_empty() {
462 let max_len = cmp::min(new_text.len(), 10);
463 let len = rng.gen_range(1..=max_len);
464 let (chunk, suffix) = new_text.split_at(len);
465 provider.send_completion(chunk);
466 new_text = suffix;
467 deterministic.run_until_parked();
468 }
469 provider.finish_completion();
470 deterministic.run_until_parked();
471
472 assert_eq!(
473 buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
474 indoc! {"
475 fn main() {
476 let mut x = 0;
477 while x < 10 {
478 x += 1;
479 }
480 }
481 "}
482 );
483 }
484
485 #[gpui::test(iterations = 10)]
486 async fn test_autoindent_when_generating_before_indentation(
487 cx: &mut TestAppContext,
488 mut rng: StdRng,
489 deterministic: Arc<Deterministic>,
490 ) {
491 cx.set_global(cx.read(SettingsStore::test));
492 cx.update(language_settings::init);
493
494 let text = concat!(
495 "fn main() {\n",
496 " \n",
497 "}\n" //
498 );
499 let buffer =
500 cx.add_model(|cx| Buffer::new(0, 0, text).with_language(Arc::new(rust_lang()), cx));
501 let buffer = cx.add_model(|cx| MultiBuffer::singleton(buffer, cx));
502 let position = buffer.read_with(cx, |buffer, cx| {
503 let snapshot = buffer.snapshot(cx);
504 snapshot.anchor_before(Point::new(1, 2))
505 });
506 let provider = Arc::new(TestCompletionProvider::new());
507 let codegen = cx.add_model(|cx| {
508 Codegen::new(
509 buffer.clone(),
510 CodegenKind::Generate { position },
511 provider.clone(),
512 cx,
513 )
514 });
515
516 let request = Box::new(DummyCompletionRequest {
517 name: "test".to_string(),
518 });
519 codegen.update(cx, |codegen, cx| codegen.start(request, cx));
520
521 let mut new_text = concat!(
522 "let mut x = 0;\n",
523 "while x < 10 {\n",
524 " x += 1;\n",
525 "}", //
526 );
527 while !new_text.is_empty() {
528 let max_len = cmp::min(new_text.len(), 10);
529 let len = rng.gen_range(1..=max_len);
530 let (chunk, suffix) = new_text.split_at(len);
531 provider.send_completion(chunk);
532 new_text = suffix;
533 deterministic.run_until_parked();
534 }
535 provider.finish_completion();
536 deterministic.run_until_parked();
537
538 assert_eq!(
539 buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
540 indoc! {"
541 fn main() {
542 let mut x = 0;
543 while x < 10 {
544 x += 1;
545 }
546 }
547 "}
548 );
549 }
550
551 #[gpui::test]
552 async fn test_strip_markdown_codeblock() {
553 assert_eq!(
554 strip_markdown_codeblock(chunks("Lorem ipsum dolor", 2))
555 .map(|chunk| chunk.unwrap())
556 .collect::<String>()
557 .await,
558 "Lorem ipsum dolor"
559 );
560 assert_eq!(
561 strip_markdown_codeblock(chunks("```\nLorem ipsum dolor", 2))
562 .map(|chunk| chunk.unwrap())
563 .collect::<String>()
564 .await,
565 "Lorem ipsum dolor"
566 );
567 assert_eq!(
568 strip_markdown_codeblock(chunks("```\nLorem ipsum dolor\n```", 2))
569 .map(|chunk| chunk.unwrap())
570 .collect::<String>()
571 .await,
572 "Lorem ipsum dolor"
573 );
574 assert_eq!(
575 strip_markdown_codeblock(chunks("```\nLorem ipsum dolor\n```\n", 2))
576 .map(|chunk| chunk.unwrap())
577 .collect::<String>()
578 .await,
579 "Lorem ipsum dolor"
580 );
581 assert_eq!(
582 strip_markdown_codeblock(chunks("```html\n```js\nLorem ipsum dolor\n```\n```", 2))
583 .map(|chunk| chunk.unwrap())
584 .collect::<String>()
585 .await,
586 "```js\nLorem ipsum dolor\n```"
587 );
588 assert_eq!(
589 strip_markdown_codeblock(chunks("``\nLorem ipsum dolor\n```", 2))
590 .map(|chunk| chunk.unwrap())
591 .collect::<String>()
592 .await,
593 "``\nLorem ipsum dolor\n```"
594 );
595
596 fn chunks(text: &str, size: usize) -> impl Stream<Item = Result<String>> {
597 stream::iter(
598 text.chars()
599 .collect::<Vec<_>>()
600 .chunks(size)
601 .map(|chunk| Ok(chunk.iter().collect::<String>()))
602 .collect::<Vec<_>>(),
603 )
604 }
605 }
606
607 struct TestCompletionProvider {
608 last_completion_tx: Mutex<Option<mpsc::Sender<String>>>,
609 }
610
611 impl TestCompletionProvider {
612 fn new() -> Self {
613 Self {
614 last_completion_tx: Mutex::new(None),
615 }
616 }
617
618 fn send_completion(&self, completion: impl Into<String>) {
619 let mut tx = self.last_completion_tx.lock();
620 tx.as_mut().unwrap().try_send(completion.into()).unwrap();
621 }
622
623 fn finish_completion(&self) {
624 self.last_completion_tx.lock().take().unwrap();
625 }
626 }
627
628 impl CompletionProvider for TestCompletionProvider {
629 fn complete(
630 &self,
631 _prompt: Box<dyn CompletionRequest>,
632 ) -> BoxFuture<'static, Result<BoxStream<'static, Result<String>>>> {
633 let (tx, rx) = mpsc::channel(1);
634 *self.last_completion_tx.lock() = Some(tx);
635 async move { Ok(rx.map(|rx| Ok(rx)).boxed()) }.boxed()
636 }
637 }
638
639 fn rust_lang() -> Language {
640 Language::new(
641 LanguageConfig {
642 name: "Rust".into(),
643 path_suffixes: vec!["rs".to_string()],
644 ..Default::default()
645 },
646 Some(tree_sitter_rust::language()),
647 )
648 .with_indents_query(
649 r#"
650 (call_expression) @indent
651 (field_expression) @indent
652 (_ "(" ")" @end) @indent
653 (_ "{" "}" @end) @indent
654 "#,
655 )
656 .unwrap()
657 }
658}