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