buffer_codegen.rs

   1use crate::{context::LoadedContext, inline_prompt_editor::CodegenStatus};
   2use agent_settings::AgentSettings;
   3use anyhow::{Context as _, Result};
   4use client::telemetry::Telemetry;
   5use cloud_llm_client::CompletionIntent;
   6use collections::HashSet;
   7use editor::{Anchor, AnchorRangeExt, MultiBuffer, MultiBufferSnapshot, ToOffset as _, ToPoint};
   8use feature_flags::{FeatureFlagAppExt as _, InlineAssistantV2FeatureFlag};
   9use futures::{
  10    SinkExt, Stream, StreamExt, TryStreamExt as _,
  11    channel::mpsc,
  12    future::{LocalBoxFuture, Shared},
  13    join,
  14};
  15use gpui::{App, AppContext as _, AsyncApp, Context, Entity, EventEmitter, Subscription, Task};
  16use language::{Buffer, IndentKind, Point, TransactionId, line_diff};
  17use language_model::{
  18    LanguageModel, LanguageModelCompletionError, LanguageModelRegistry, LanguageModelRequest,
  19    LanguageModelRequestMessage, LanguageModelRequestTool, LanguageModelTextStream, Role,
  20    report_assistant_event,
  21};
  22use multi_buffer::MultiBufferRow;
  23use parking_lot::Mutex;
  24use prompt_store::PromptBuilder;
  25use rope::Rope;
  26use schemars::JsonSchema;
  27use serde::{Deserialize, Serialize};
  28use smol::future::FutureExt;
  29use std::{
  30    cmp,
  31    future::Future,
  32    iter,
  33    ops::{Range, RangeInclusive},
  34    pin::Pin,
  35    sync::Arc,
  36    task::{self, Poll},
  37    time::Instant,
  38};
  39use streaming_diff::{CharOperation, LineDiff, LineOperation, StreamingDiff};
  40use telemetry_events::{AssistantEventData, AssistantKind, AssistantPhase};
  41use ui::SharedString;
  42
  43/// Use this tool to provide a message to the user when you're unable to complete a task.
  44#[derive(Debug, Serialize, Deserialize, JsonSchema)]
  45pub struct FailureMessageInput {
  46    /// A brief message to the user explaining why you're unable to fulfill the request or to ask a question about the request.
  47    ///
  48    /// The message may use markdown formatting if you wish.
  49    pub message: String,
  50}
  51
  52/// Replaces text in <rewrite_this></rewrite_this> tags with your replacement_text.
  53#[derive(Debug, Serialize, Deserialize, JsonSchema)]
  54pub struct RewriteSectionInput {
  55    /// A brief description of the edit you have made.
  56    ///
  57    /// The description may use markdown formatting if you wish.
  58    /// This is optional - if the edit is simple or obvious, you should leave it empty.
  59    pub description: String,
  60
  61    /// The text to replace the section with.
  62    pub replacement_text: String,
  63}
  64
  65pub struct BufferCodegen {
  66    alternatives: Vec<Entity<CodegenAlternative>>,
  67    pub active_alternative: usize,
  68    seen_alternatives: HashSet<usize>,
  69    subscriptions: Vec<Subscription>,
  70    buffer: Entity<MultiBuffer>,
  71    range: Range<Anchor>,
  72    initial_transaction_id: Option<TransactionId>,
  73    telemetry: Arc<Telemetry>,
  74    builder: Arc<PromptBuilder>,
  75    pub is_insertion: bool,
  76}
  77
  78impl BufferCodegen {
  79    pub fn new(
  80        buffer: Entity<MultiBuffer>,
  81        range: Range<Anchor>,
  82        initial_transaction_id: Option<TransactionId>,
  83        telemetry: Arc<Telemetry>,
  84        builder: Arc<PromptBuilder>,
  85        cx: &mut Context<Self>,
  86    ) -> Self {
  87        let codegen = cx.new(|cx| {
  88            CodegenAlternative::new(
  89                buffer.clone(),
  90                range.clone(),
  91                false,
  92                Some(telemetry.clone()),
  93                builder.clone(),
  94                cx,
  95            )
  96        });
  97        let mut this = Self {
  98            is_insertion: range.to_offset(&buffer.read(cx).snapshot(cx)).is_empty(),
  99            alternatives: vec![codegen],
 100            active_alternative: 0,
 101            seen_alternatives: HashSet::default(),
 102            subscriptions: Vec::new(),
 103            buffer,
 104            range,
 105            initial_transaction_id,
 106            telemetry,
 107            builder,
 108        };
 109        this.activate(0, cx);
 110        this
 111    }
 112
 113    fn subscribe_to_alternative(&mut self, cx: &mut Context<Self>) {
 114        let codegen = self.active_alternative().clone();
 115        self.subscriptions.clear();
 116        self.subscriptions
 117            .push(cx.observe(&codegen, |_, _, cx| cx.notify()));
 118        self.subscriptions
 119            .push(cx.subscribe(&codegen, |_, _, event, cx| cx.emit(*event)));
 120    }
 121
 122    pub fn active_alternative(&self) -> &Entity<CodegenAlternative> {
 123        &self.alternatives[self.active_alternative]
 124    }
 125
 126    pub fn status<'a>(&self, cx: &'a App) -> &'a CodegenStatus {
 127        &self.active_alternative().read(cx).status
 128    }
 129
 130    pub fn alternative_count(&self, cx: &App) -> usize {
 131        LanguageModelRegistry::read_global(cx)
 132            .inline_alternative_models()
 133            .len()
 134            + 1
 135    }
 136
 137    pub fn cycle_prev(&mut self, cx: &mut Context<Self>) {
 138        let next_active_ix = if self.active_alternative == 0 {
 139            self.alternatives.len() - 1
 140        } else {
 141            self.active_alternative - 1
 142        };
 143        self.activate(next_active_ix, cx);
 144    }
 145
 146    pub fn cycle_next(&mut self, cx: &mut Context<Self>) {
 147        let next_active_ix = (self.active_alternative + 1) % self.alternatives.len();
 148        self.activate(next_active_ix, cx);
 149    }
 150
 151    fn activate(&mut self, index: usize, cx: &mut Context<Self>) {
 152        self.active_alternative()
 153            .update(cx, |codegen, cx| codegen.set_active(false, cx));
 154        self.seen_alternatives.insert(index);
 155        self.active_alternative = index;
 156        self.active_alternative()
 157            .update(cx, |codegen, cx| codegen.set_active(true, cx));
 158        self.subscribe_to_alternative(cx);
 159        cx.notify();
 160    }
 161
 162    pub fn start(
 163        &mut self,
 164        primary_model: Arc<dyn LanguageModel>,
 165        user_prompt: String,
 166        context_task: Shared<Task<Option<LoadedContext>>>,
 167        cx: &mut Context<Self>,
 168    ) -> Result<()> {
 169        let alternative_models = LanguageModelRegistry::read_global(cx)
 170            .inline_alternative_models()
 171            .to_vec();
 172
 173        self.active_alternative()
 174            .update(cx, |alternative, cx| alternative.undo(cx));
 175        self.activate(0, cx);
 176        self.alternatives.truncate(1);
 177
 178        for _ in 0..alternative_models.len() {
 179            self.alternatives.push(cx.new(|cx| {
 180                CodegenAlternative::new(
 181                    self.buffer.clone(),
 182                    self.range.clone(),
 183                    false,
 184                    Some(self.telemetry.clone()),
 185                    self.builder.clone(),
 186                    cx,
 187                )
 188            }));
 189        }
 190
 191        for (model, alternative) in iter::once(primary_model)
 192            .chain(alternative_models)
 193            .zip(&self.alternatives)
 194        {
 195            alternative.update(cx, |alternative, cx| {
 196                alternative.start(user_prompt.clone(), context_task.clone(), model.clone(), cx)
 197            })?;
 198        }
 199
 200        Ok(())
 201    }
 202
 203    pub fn stop(&mut self, cx: &mut Context<Self>) {
 204        for codegen in &self.alternatives {
 205            codegen.update(cx, |codegen, cx| codegen.stop(cx));
 206        }
 207    }
 208
 209    pub fn undo(&mut self, cx: &mut Context<Self>) {
 210        self.active_alternative()
 211            .update(cx, |codegen, cx| codegen.undo(cx));
 212
 213        self.buffer.update(cx, |buffer, cx| {
 214            if let Some(transaction_id) = self.initial_transaction_id.take() {
 215                buffer.undo_transaction(transaction_id, cx);
 216                buffer.refresh_preview(cx);
 217            }
 218        });
 219    }
 220
 221    pub fn buffer(&self, cx: &App) -> Entity<MultiBuffer> {
 222        self.active_alternative().read(cx).buffer.clone()
 223    }
 224
 225    pub fn old_buffer(&self, cx: &App) -> Entity<Buffer> {
 226        self.active_alternative().read(cx).old_buffer.clone()
 227    }
 228
 229    pub fn snapshot(&self, cx: &App) -> MultiBufferSnapshot {
 230        self.active_alternative().read(cx).snapshot.clone()
 231    }
 232
 233    pub fn edit_position(&self, cx: &App) -> Option<Anchor> {
 234        self.active_alternative().read(cx).edit_position
 235    }
 236
 237    pub fn diff<'a>(&self, cx: &'a App) -> &'a Diff {
 238        &self.active_alternative().read(cx).diff
 239    }
 240
 241    pub fn last_equal_ranges<'a>(&self, cx: &'a App) -> &'a [Range<Anchor>] {
 242        self.active_alternative().read(cx).last_equal_ranges()
 243    }
 244}
 245
 246impl EventEmitter<CodegenEvent> for BufferCodegen {}
 247
 248pub struct CodegenAlternative {
 249    buffer: Entity<MultiBuffer>,
 250    old_buffer: Entity<Buffer>,
 251    snapshot: MultiBufferSnapshot,
 252    edit_position: Option<Anchor>,
 253    range: Range<Anchor>,
 254    last_equal_ranges: Vec<Range<Anchor>>,
 255    transformation_transaction_id: Option<TransactionId>,
 256    status: CodegenStatus,
 257    generation: Task<()>,
 258    diff: Diff,
 259    telemetry: Option<Arc<Telemetry>>,
 260    _subscription: gpui::Subscription,
 261    builder: Arc<PromptBuilder>,
 262    active: bool,
 263    edits: Vec<(Range<Anchor>, String)>,
 264    line_operations: Vec<LineOperation>,
 265    elapsed_time: Option<f64>,
 266    completion: Option<String>,
 267    pub message_id: Option<String>,
 268    pub model_explanation: Option<SharedString>,
 269}
 270
 271impl EventEmitter<CodegenEvent> for CodegenAlternative {}
 272
 273impl CodegenAlternative {
 274    pub fn new(
 275        buffer: Entity<MultiBuffer>,
 276        range: Range<Anchor>,
 277        active: bool,
 278        telemetry: Option<Arc<Telemetry>>,
 279        builder: Arc<PromptBuilder>,
 280        cx: &mut Context<Self>,
 281    ) -> Self {
 282        let snapshot = buffer.read(cx).snapshot(cx);
 283
 284        let (old_buffer, _, _) = snapshot
 285            .range_to_buffer_ranges(range.clone())
 286            .pop()
 287            .unwrap();
 288        let old_buffer = cx.new(|cx| {
 289            let text = old_buffer.as_rope().clone();
 290            let line_ending = old_buffer.line_ending();
 291            let language = old_buffer.language().cloned();
 292            let language_registry = buffer
 293                .read(cx)
 294                .buffer(old_buffer.remote_id())
 295                .unwrap()
 296                .read(cx)
 297                .language_registry();
 298
 299            let mut buffer = Buffer::local_normalized(text, line_ending, cx);
 300            buffer.set_language(language, cx);
 301            if let Some(language_registry) = language_registry {
 302                buffer.set_language_registry(language_registry);
 303            }
 304            buffer
 305        });
 306
 307        Self {
 308            buffer: buffer.clone(),
 309            old_buffer,
 310            edit_position: None,
 311            message_id: None,
 312            snapshot,
 313            last_equal_ranges: Default::default(),
 314            transformation_transaction_id: None,
 315            status: CodegenStatus::Idle,
 316            generation: Task::ready(()),
 317            diff: Diff::default(),
 318            telemetry,
 319            builder,
 320            active: active,
 321            edits: Vec::new(),
 322            line_operations: Vec::new(),
 323            range,
 324            elapsed_time: None,
 325            completion: None,
 326            model_explanation: None,
 327            _subscription: cx.subscribe(&buffer, Self::handle_buffer_event),
 328        }
 329    }
 330
 331    pub fn set_active(&mut self, active: bool, cx: &mut Context<Self>) {
 332        if active != self.active {
 333            self.active = active;
 334
 335            if self.active {
 336                let edits = self.edits.clone();
 337                self.apply_edits(edits, cx);
 338                if matches!(self.status, CodegenStatus::Pending) {
 339                    let line_operations = self.line_operations.clone();
 340                    self.reapply_line_based_diff(line_operations, cx);
 341                } else {
 342                    self.reapply_batch_diff(cx).detach();
 343                }
 344            } else if let Some(transaction_id) = self.transformation_transaction_id.take() {
 345                self.buffer.update(cx, |buffer, cx| {
 346                    buffer.undo_transaction(transaction_id, cx);
 347                    buffer.forget_transaction(transaction_id, cx);
 348                });
 349            }
 350        }
 351    }
 352
 353    fn handle_buffer_event(
 354        &mut self,
 355        _buffer: Entity<MultiBuffer>,
 356        event: &multi_buffer::Event,
 357        cx: &mut Context<Self>,
 358    ) {
 359        if let multi_buffer::Event::TransactionUndone { transaction_id } = event
 360            && self.transformation_transaction_id == Some(*transaction_id)
 361        {
 362            self.transformation_transaction_id = None;
 363            self.generation = Task::ready(());
 364            cx.emit(CodegenEvent::Undone);
 365        }
 366    }
 367
 368    pub fn last_equal_ranges(&self) -> &[Range<Anchor>] {
 369        &self.last_equal_ranges
 370    }
 371
 372    pub fn start(
 373        &mut self,
 374        user_prompt: String,
 375        context_task: Shared<Task<Option<LoadedContext>>>,
 376        model: Arc<dyn LanguageModel>,
 377        cx: &mut Context<Self>,
 378    ) -> Result<()> {
 379        if let Some(transformation_transaction_id) = self.transformation_transaction_id.take() {
 380            self.buffer.update(cx, |buffer, cx| {
 381                buffer.undo_transaction(transformation_transaction_id, cx);
 382            });
 383        }
 384
 385        self.edit_position = Some(self.range.start.bias_right(&self.snapshot));
 386
 387        let api_key = model.api_key(cx);
 388        let telemetry_id = model.telemetry_id();
 389        let provider_id = model.provider_id();
 390
 391        if cx.has_flag::<InlineAssistantV2FeatureFlag>() {
 392            let request = self.build_request(&model, user_prompt, context_task, cx)?;
 393            let tool_use =
 394                cx.spawn(async move |_, cx| model.stream_completion_tool(request.await, cx).await);
 395            self.handle_tool_use(telemetry_id, provider_id.to_string(), api_key, tool_use, cx);
 396        } else {
 397            let stream: LocalBoxFuture<Result<LanguageModelTextStream>> =
 398                if user_prompt.trim().to_lowercase() == "delete" {
 399                    async { Ok(LanguageModelTextStream::default()) }.boxed_local()
 400                } else {
 401                    let request = self.build_request(&model, user_prompt, context_task, cx)?;
 402                    cx.spawn(async move |_, cx| {
 403                        Ok(model.stream_completion_text(request.await, cx).await?)
 404                    })
 405                    .boxed_local()
 406                };
 407            self.handle_stream(telemetry_id, provider_id.to_string(), api_key, stream, cx);
 408        }
 409
 410        Ok(())
 411    }
 412
 413    fn build_request_v2(
 414        &self,
 415        model: &Arc<dyn LanguageModel>,
 416        user_prompt: String,
 417        context_task: Shared<Task<Option<LoadedContext>>>,
 418        cx: &mut App,
 419    ) -> Result<Task<LanguageModelRequest>> {
 420        let buffer = self.buffer.read(cx).snapshot(cx);
 421        let language = buffer.language_at(self.range.start);
 422        let language_name = if let Some(language) = language.as_ref() {
 423            if Arc::ptr_eq(language, &language::PLAIN_TEXT) {
 424                None
 425            } else {
 426                Some(language.name())
 427            }
 428        } else {
 429            None
 430        };
 431
 432        let language_name = language_name.as_ref();
 433        let start = buffer.point_to_buffer_offset(self.range.start);
 434        let end = buffer.point_to_buffer_offset(self.range.end);
 435        let (buffer, range) = if let Some((start, end)) = start.zip(end) {
 436            let (start_buffer, start_buffer_offset) = start;
 437            let (end_buffer, end_buffer_offset) = end;
 438            if start_buffer.remote_id() == end_buffer.remote_id() {
 439                (start_buffer.clone(), start_buffer_offset..end_buffer_offset)
 440            } else {
 441                anyhow::bail!("invalid transformation range");
 442            }
 443        } else {
 444            anyhow::bail!("invalid transformation range");
 445        };
 446
 447        let system_prompt = self
 448            .builder
 449            .generate_inline_transformation_prompt_v2(
 450                language_name,
 451                buffer,
 452                range.start.0..range.end.0,
 453            )
 454            .context("generating content prompt")?;
 455
 456        let temperature = AgentSettings::temperature_for_model(model, cx);
 457
 458        let tool_input_format = model.tool_input_format();
 459
 460        Ok(cx.spawn(async move |_cx| {
 461            let mut messages = vec![LanguageModelRequestMessage {
 462                role: Role::System,
 463                content: vec![system_prompt.into()],
 464                cache: false,
 465                reasoning_details: None,
 466            }];
 467
 468            let mut user_message = LanguageModelRequestMessage {
 469                role: Role::User,
 470                content: Vec::new(),
 471                cache: false,
 472                reasoning_details: None,
 473            };
 474
 475            if let Some(context) = context_task.await {
 476                context.add_to_request_message(&mut user_message);
 477            }
 478
 479            user_message.content.push(user_prompt.into());
 480            messages.push(user_message);
 481
 482            let tools = vec![
 483                LanguageModelRequestTool {
 484                    name: "rewrite_section".to_string(),
 485                    description: "Replaces text in <rewrite_this></rewrite_this> tags with your replacement_text.".to_string(),
 486                    input_schema: language_model::tool_schema::root_schema_for::<RewriteSectionInput>(tool_input_format).to_value(),
 487                },
 488                LanguageModelRequestTool {
 489                    name: "failure_message".to_string(),
 490                    description: "Use this tool to provide a message to the user when you're unable to complete a task.".to_string(),
 491                    input_schema: language_model::tool_schema::root_schema_for::<FailureMessageInput>(tool_input_format).to_value(),
 492                },
 493            ];
 494
 495            LanguageModelRequest {
 496                thread_id: None,
 497                prompt_id: None,
 498                intent: Some(CompletionIntent::InlineAssist),
 499                mode: None,
 500                tools,
 501                tool_choice: None,
 502                stop: Vec::new(),
 503                temperature,
 504                messages,
 505                thinking_allowed: false,
 506            }
 507        }))
 508    }
 509
 510    fn build_request(
 511        &self,
 512        model: &Arc<dyn LanguageModel>,
 513        user_prompt: String,
 514        context_task: Shared<Task<Option<LoadedContext>>>,
 515        cx: &mut App,
 516    ) -> Result<Task<LanguageModelRequest>> {
 517        if cx.has_flag::<InlineAssistantV2FeatureFlag>() {
 518            return self.build_request_v2(model, user_prompt, context_task, cx);
 519        }
 520
 521        let buffer = self.buffer.read(cx).snapshot(cx);
 522        let language = buffer.language_at(self.range.start);
 523        let language_name = if let Some(language) = language.as_ref() {
 524            if Arc::ptr_eq(language, &language::PLAIN_TEXT) {
 525                None
 526            } else {
 527                Some(language.name())
 528            }
 529        } else {
 530            None
 531        };
 532
 533        let language_name = language_name.as_ref();
 534        let start = buffer.point_to_buffer_offset(self.range.start);
 535        let end = buffer.point_to_buffer_offset(self.range.end);
 536        let (buffer, range) = if let Some((start, end)) = start.zip(end) {
 537            let (start_buffer, start_buffer_offset) = start;
 538            let (end_buffer, end_buffer_offset) = end;
 539            if start_buffer.remote_id() == end_buffer.remote_id() {
 540                (start_buffer.clone(), start_buffer_offset..end_buffer_offset)
 541            } else {
 542                anyhow::bail!("invalid transformation range");
 543            }
 544        } else {
 545            anyhow::bail!("invalid transformation range");
 546        };
 547
 548        let prompt = self
 549            .builder
 550            .generate_inline_transformation_prompt(
 551                user_prompt,
 552                language_name,
 553                buffer,
 554                range.start.0..range.end.0,
 555            )
 556            .context("generating content prompt")?;
 557
 558        let temperature = AgentSettings::temperature_for_model(model, cx);
 559
 560        Ok(cx.spawn(async move |_cx| {
 561            let mut request_message = LanguageModelRequestMessage {
 562                role: Role::User,
 563                content: Vec::new(),
 564                cache: false,
 565                reasoning_details: None,
 566            };
 567
 568            if let Some(context) = context_task.await {
 569                context.add_to_request_message(&mut request_message);
 570            }
 571
 572            request_message.content.push(prompt.into());
 573
 574            LanguageModelRequest {
 575                thread_id: None,
 576                prompt_id: None,
 577                intent: Some(CompletionIntent::InlineAssist),
 578                mode: None,
 579                tools: Vec::new(),
 580                tool_choice: None,
 581                stop: Vec::new(),
 582                temperature,
 583                messages: vec![request_message],
 584                thinking_allowed: false,
 585            }
 586        }))
 587    }
 588
 589    pub fn handle_stream(
 590        &mut self,
 591        model_telemetry_id: String,
 592        model_provider_id: String,
 593        model_api_key: Option<String>,
 594        stream: impl 'static + Future<Output = Result<LanguageModelTextStream>>,
 595        cx: &mut Context<Self>,
 596    ) {
 597        let start_time = Instant::now();
 598
 599        // Make a new snapshot and re-resolve anchor in case the document was modified.
 600        // This can happen often if the editor loses focus and is saved + reformatted,
 601        // as in https://github.com/zed-industries/zed/issues/39088
 602        self.snapshot = self.buffer.read(cx).snapshot(cx);
 603        self.range = self.snapshot.anchor_after(self.range.start)
 604            ..self.snapshot.anchor_after(self.range.end);
 605
 606        let snapshot = self.snapshot.clone();
 607        let selected_text = snapshot
 608            .text_for_range(self.range.start..self.range.end)
 609            .collect::<Rope>();
 610
 611        let selection_start = self.range.start.to_point(&snapshot);
 612
 613        // Start with the indentation of the first line in the selection
 614        let mut suggested_line_indent = snapshot
 615            .suggested_indents(selection_start.row..=selection_start.row, cx)
 616            .into_values()
 617            .next()
 618            .unwrap_or_else(|| snapshot.indent_size_for_line(MultiBufferRow(selection_start.row)));
 619
 620        // If the first line in the selection does not have indentation, check the following lines
 621        if suggested_line_indent.len == 0 && suggested_line_indent.kind == IndentKind::Space {
 622            for row in selection_start.row..=self.range.end.to_point(&snapshot).row {
 623                let line_indent = snapshot.indent_size_for_line(MultiBufferRow(row));
 624                // Prefer tabs if a line in the selection uses tabs as indentation
 625                if line_indent.kind == IndentKind::Tab {
 626                    suggested_line_indent.kind = IndentKind::Tab;
 627                    break;
 628                }
 629            }
 630        }
 631
 632        let http_client = cx.http_client();
 633        let telemetry = self.telemetry.clone();
 634        let language_name = {
 635            let multibuffer = self.buffer.read(cx);
 636            let snapshot = multibuffer.snapshot(cx);
 637            let ranges = snapshot.range_to_buffer_ranges(self.range.clone());
 638            ranges
 639                .first()
 640                .and_then(|(buffer, _, _)| buffer.language())
 641                .map(|language| language.name())
 642        };
 643
 644        self.diff = Diff::default();
 645        self.status = CodegenStatus::Pending;
 646        let mut edit_start = self.range.start.to_offset(&snapshot);
 647        let completion = Arc::new(Mutex::new(String::new()));
 648        let completion_clone = completion.clone();
 649
 650        self.generation = cx.spawn(async move |codegen, cx| {
 651            let stream = stream.await;
 652
 653            let token_usage = stream
 654                .as_ref()
 655                .ok()
 656                .map(|stream| stream.last_token_usage.clone());
 657            let message_id = stream
 658                .as_ref()
 659                .ok()
 660                .and_then(|stream| stream.message_id.clone());
 661            let generate = async {
 662                let model_telemetry_id = model_telemetry_id.clone();
 663                let model_provider_id = model_provider_id.clone();
 664                let (mut diff_tx, mut diff_rx) = mpsc::channel(1);
 665                let executor = cx.background_executor().clone();
 666                let message_id = message_id.clone();
 667                let line_based_stream_diff: Task<anyhow::Result<()>> =
 668                    cx.background_spawn(async move {
 669                        let mut response_latency = None;
 670                        let request_start = Instant::now();
 671                        let diff = async {
 672                            let chunks = StripInvalidSpans::new(
 673                                stream?.stream.map_err(|error| error.into()),
 674                            );
 675                            futures::pin_mut!(chunks);
 676                            let mut diff = StreamingDiff::new(selected_text.to_string());
 677                            let mut line_diff = LineDiff::default();
 678
 679                            let mut new_text = String::new();
 680                            let mut base_indent = None;
 681                            let mut line_indent = None;
 682                            let mut first_line = true;
 683
 684                            while let Some(chunk) = chunks.next().await {
 685                                if response_latency.is_none() {
 686                                    response_latency = Some(request_start.elapsed());
 687                                }
 688                                let chunk = chunk?;
 689                                completion_clone.lock().push_str(&chunk);
 690
 691                                let mut lines = chunk.split('\n').peekable();
 692                                while let Some(line) = lines.next() {
 693                                    new_text.push_str(line);
 694                                    if line_indent.is_none()
 695                                        && let Some(non_whitespace_ch_ix) =
 696                                            new_text.find(|ch: char| !ch.is_whitespace())
 697                                    {
 698                                        line_indent = Some(non_whitespace_ch_ix);
 699                                        base_indent = base_indent.or(line_indent);
 700
 701                                        let line_indent = line_indent.unwrap();
 702                                        let base_indent = base_indent.unwrap();
 703                                        let indent_delta = line_indent as i32 - base_indent as i32;
 704                                        let mut corrected_indent_len = cmp::max(
 705                                            0,
 706                                            suggested_line_indent.len as i32 + indent_delta,
 707                                        )
 708                                            as usize;
 709                                        if first_line {
 710                                            corrected_indent_len = corrected_indent_len
 711                                                .saturating_sub(selection_start.column as usize);
 712                                        }
 713
 714                                        let indent_char = suggested_line_indent.char();
 715                                        let mut indent_buffer = [0; 4];
 716                                        let indent_str =
 717                                            indent_char.encode_utf8(&mut indent_buffer);
 718                                        new_text.replace_range(
 719                                            ..line_indent,
 720                                            &indent_str.repeat(corrected_indent_len),
 721                                        );
 722                                    }
 723
 724                                    if line_indent.is_some() {
 725                                        let char_ops = diff.push_new(&new_text);
 726                                        line_diff.push_char_operations(&char_ops, &selected_text);
 727                                        diff_tx
 728                                            .send((char_ops, line_diff.line_operations()))
 729                                            .await?;
 730                                        new_text.clear();
 731                                    }
 732
 733                                    if lines.peek().is_some() {
 734                                        let char_ops = diff.push_new("\n");
 735                                        line_diff.push_char_operations(&char_ops, &selected_text);
 736                                        diff_tx
 737                                            .send((char_ops, line_diff.line_operations()))
 738                                            .await?;
 739                                        if line_indent.is_none() {
 740                                            // Don't write out the leading indentation in empty lines on the next line
 741                                            // This is the case where the above if statement didn't clear the buffer
 742                                            new_text.clear();
 743                                        }
 744                                        line_indent = None;
 745                                        first_line = false;
 746                                    }
 747                                }
 748                            }
 749
 750                            let mut char_ops = diff.push_new(&new_text);
 751                            char_ops.extend(diff.finish());
 752                            line_diff.push_char_operations(&char_ops, &selected_text);
 753                            line_diff.finish(&selected_text);
 754                            diff_tx
 755                                .send((char_ops, line_diff.line_operations()))
 756                                .await?;
 757
 758                            anyhow::Ok(())
 759                        };
 760
 761                        let result = diff.await;
 762
 763                        let error_message = result.as_ref().err().map(|error| error.to_string());
 764                        report_assistant_event(
 765                            AssistantEventData {
 766                                conversation_id: None,
 767                                message_id,
 768                                kind: AssistantKind::Inline,
 769                                phase: AssistantPhase::Response,
 770                                model: model_telemetry_id,
 771                                model_provider: model_provider_id,
 772                                response_latency,
 773                                error_message,
 774                                language_name: language_name.map(|name| name.to_proto()),
 775                            },
 776                            telemetry,
 777                            http_client,
 778                            model_api_key,
 779                            &executor,
 780                        );
 781
 782                        result?;
 783                        Ok(())
 784                    });
 785
 786                while let Some((char_ops, line_ops)) = diff_rx.next().await {
 787                    codegen.update(cx, |codegen, cx| {
 788                        codegen.last_equal_ranges.clear();
 789
 790                        let edits = char_ops
 791                            .into_iter()
 792                            .filter_map(|operation| match operation {
 793                                CharOperation::Insert { text } => {
 794                                    let edit_start = snapshot.anchor_after(edit_start);
 795                                    Some((edit_start..edit_start, text))
 796                                }
 797                                CharOperation::Delete { bytes } => {
 798                                    let edit_end = edit_start + bytes;
 799                                    let edit_range = snapshot.anchor_after(edit_start)
 800                                        ..snapshot.anchor_before(edit_end);
 801                                    edit_start = edit_end;
 802                                    Some((edit_range, String::new()))
 803                                }
 804                                CharOperation::Keep { bytes } => {
 805                                    let edit_end = edit_start + bytes;
 806                                    let edit_range = snapshot.anchor_after(edit_start)
 807                                        ..snapshot.anchor_before(edit_end);
 808                                    edit_start = edit_end;
 809                                    codegen.last_equal_ranges.push(edit_range);
 810                                    None
 811                                }
 812                            })
 813                            .collect::<Vec<_>>();
 814
 815                        if codegen.active {
 816                            codegen.apply_edits(edits.iter().cloned(), cx);
 817                            codegen.reapply_line_based_diff(line_ops.iter().cloned(), cx);
 818                        }
 819                        codegen.edits.extend(edits);
 820                        codegen.line_operations = line_ops;
 821                        codegen.edit_position = Some(snapshot.anchor_after(edit_start));
 822
 823                        cx.notify();
 824                    })?;
 825                }
 826
 827                // Streaming stopped and we have the new text in the buffer, and a line-based diff applied for the whole new buffer.
 828                // That diff is not what a regular diff is and might look unexpected, ergo apply a regular diff.
 829                // It's fine to apply even if the rest of the line diffing fails, as no more hunks are coming through `diff_rx`.
 830                let batch_diff_task =
 831                    codegen.update(cx, |codegen, cx| codegen.reapply_batch_diff(cx))?;
 832                let (line_based_stream_diff, ()) = join!(line_based_stream_diff, batch_diff_task);
 833                line_based_stream_diff?;
 834
 835                anyhow::Ok(())
 836            };
 837
 838            let result = generate.await;
 839            let elapsed_time = start_time.elapsed().as_secs_f64();
 840
 841            codegen
 842                .update(cx, |this, cx| {
 843                    this.message_id = message_id;
 844                    this.last_equal_ranges.clear();
 845                    if let Err(error) = result {
 846                        this.status = CodegenStatus::Error(error);
 847                    } else {
 848                        this.status = CodegenStatus::Done;
 849                    }
 850                    this.elapsed_time = Some(elapsed_time);
 851                    this.completion = Some(completion.lock().clone());
 852                    if let Some(usage) = token_usage {
 853                        let usage = usage.lock();
 854                        telemetry::event!(
 855                            "Inline Assistant Completion",
 856                            model = model_telemetry_id,
 857                            model_provider = model_provider_id,
 858                            input_tokens = usage.input_tokens,
 859                            output_tokens = usage.output_tokens,
 860                        )
 861                    }
 862
 863                    cx.emit(CodegenEvent::Finished);
 864                    cx.notify();
 865                })
 866                .ok();
 867        });
 868        cx.notify();
 869    }
 870
 871    pub fn stop(&mut self, cx: &mut Context<Self>) {
 872        self.last_equal_ranges.clear();
 873        if self.diff.is_empty() {
 874            self.status = CodegenStatus::Idle;
 875        } else {
 876            self.status = CodegenStatus::Done;
 877        }
 878        self.generation = Task::ready(());
 879        cx.emit(CodegenEvent::Finished);
 880        cx.notify();
 881    }
 882
 883    pub fn undo(&mut self, cx: &mut Context<Self>) {
 884        self.buffer.update(cx, |buffer, cx| {
 885            if let Some(transaction_id) = self.transformation_transaction_id.take() {
 886                buffer.undo_transaction(transaction_id, cx);
 887                buffer.refresh_preview(cx);
 888            }
 889        });
 890    }
 891
 892    fn apply_edits(
 893        &mut self,
 894        edits: impl IntoIterator<Item = (Range<Anchor>, String)>,
 895        cx: &mut Context<CodegenAlternative>,
 896    ) {
 897        let transaction = self.buffer.update(cx, |buffer, cx| {
 898            // Avoid grouping agent edits with user edits.
 899            buffer.finalize_last_transaction(cx);
 900            buffer.start_transaction(cx);
 901            buffer.edit(edits, None, cx);
 902            buffer.end_transaction(cx)
 903        });
 904
 905        if let Some(transaction) = transaction {
 906            if let Some(first_transaction) = self.transformation_transaction_id {
 907                // Group all agent edits into the first transaction.
 908                self.buffer.update(cx, |buffer, cx| {
 909                    buffer.merge_transactions(transaction, first_transaction, cx)
 910                });
 911            } else {
 912                self.transformation_transaction_id = Some(transaction);
 913                self.buffer
 914                    .update(cx, |buffer, cx| buffer.finalize_last_transaction(cx));
 915            }
 916        }
 917    }
 918
 919    fn reapply_line_based_diff(
 920        &mut self,
 921        line_operations: impl IntoIterator<Item = LineOperation>,
 922        cx: &mut Context<Self>,
 923    ) {
 924        let old_snapshot = self.snapshot.clone();
 925        let old_range = self.range.to_point(&old_snapshot);
 926        let new_snapshot = self.buffer.read(cx).snapshot(cx);
 927        let new_range = self.range.to_point(&new_snapshot);
 928
 929        let mut old_row = old_range.start.row;
 930        let mut new_row = new_range.start.row;
 931
 932        self.diff.deleted_row_ranges.clear();
 933        self.diff.inserted_row_ranges.clear();
 934        for operation in line_operations {
 935            match operation {
 936                LineOperation::Keep { lines } => {
 937                    old_row += lines;
 938                    new_row += lines;
 939                }
 940                LineOperation::Delete { lines } => {
 941                    let old_end_row = old_row + lines - 1;
 942                    let new_row = new_snapshot.anchor_before(Point::new(new_row, 0));
 943
 944                    if let Some((_, last_deleted_row_range)) =
 945                        self.diff.deleted_row_ranges.last_mut()
 946                    {
 947                        if *last_deleted_row_range.end() + 1 == old_row {
 948                            *last_deleted_row_range = *last_deleted_row_range.start()..=old_end_row;
 949                        } else {
 950                            self.diff
 951                                .deleted_row_ranges
 952                                .push((new_row, old_row..=old_end_row));
 953                        }
 954                    } else {
 955                        self.diff
 956                            .deleted_row_ranges
 957                            .push((new_row, old_row..=old_end_row));
 958                    }
 959
 960                    old_row += lines;
 961                }
 962                LineOperation::Insert { lines } => {
 963                    let new_end_row = new_row + lines - 1;
 964                    let start = new_snapshot.anchor_before(Point::new(new_row, 0));
 965                    let end = new_snapshot.anchor_before(Point::new(
 966                        new_end_row,
 967                        new_snapshot.line_len(MultiBufferRow(new_end_row)),
 968                    ));
 969                    self.diff.inserted_row_ranges.push(start..end);
 970                    new_row += lines;
 971                }
 972            }
 973
 974            cx.notify();
 975        }
 976    }
 977
 978    fn reapply_batch_diff(&mut self, cx: &mut Context<Self>) -> Task<()> {
 979        let old_snapshot = self.snapshot.clone();
 980        let old_range = self.range.to_point(&old_snapshot);
 981        let new_snapshot = self.buffer.read(cx).snapshot(cx);
 982        let new_range = self.range.to_point(&new_snapshot);
 983
 984        cx.spawn(async move |codegen, cx| {
 985            let (deleted_row_ranges, inserted_row_ranges) = cx
 986                .background_spawn(async move {
 987                    let old_text = old_snapshot
 988                        .text_for_range(
 989                            Point::new(old_range.start.row, 0)
 990                                ..Point::new(
 991                                    old_range.end.row,
 992                                    old_snapshot.line_len(MultiBufferRow(old_range.end.row)),
 993                                ),
 994                        )
 995                        .collect::<String>();
 996                    let new_text = new_snapshot
 997                        .text_for_range(
 998                            Point::new(new_range.start.row, 0)
 999                                ..Point::new(
1000                                    new_range.end.row,
1001                                    new_snapshot.line_len(MultiBufferRow(new_range.end.row)),
1002                                ),
1003                        )
1004                        .collect::<String>();
1005
1006                    let old_start_row = old_range.start.row;
1007                    let new_start_row = new_range.start.row;
1008                    let mut deleted_row_ranges: Vec<(Anchor, RangeInclusive<u32>)> = Vec::new();
1009                    let mut inserted_row_ranges = Vec::new();
1010                    for (old_rows, new_rows) in line_diff(&old_text, &new_text) {
1011                        let old_rows = old_start_row + old_rows.start..old_start_row + old_rows.end;
1012                        let new_rows = new_start_row + new_rows.start..new_start_row + new_rows.end;
1013                        if !old_rows.is_empty() {
1014                            deleted_row_ranges.push((
1015                                new_snapshot.anchor_before(Point::new(new_rows.start, 0)),
1016                                old_rows.start..=old_rows.end - 1,
1017                            ));
1018                        }
1019                        if !new_rows.is_empty() {
1020                            let start = new_snapshot.anchor_before(Point::new(new_rows.start, 0));
1021                            let new_end_row = new_rows.end - 1;
1022                            let end = new_snapshot.anchor_before(Point::new(
1023                                new_end_row,
1024                                new_snapshot.line_len(MultiBufferRow(new_end_row)),
1025                            ));
1026                            inserted_row_ranges.push(start..end);
1027                        }
1028                    }
1029                    (deleted_row_ranges, inserted_row_ranges)
1030                })
1031                .await;
1032
1033            codegen
1034                .update(cx, |codegen, cx| {
1035                    codegen.diff.deleted_row_ranges = deleted_row_ranges;
1036                    codegen.diff.inserted_row_ranges = inserted_row_ranges;
1037                    cx.notify();
1038                })
1039                .ok();
1040        })
1041    }
1042
1043    fn handle_tool_use(
1044        &mut self,
1045        _telemetry_id: String,
1046        _provider_id: String,
1047        _api_key: Option<String>,
1048        tool_use: impl 'static
1049        + Future<
1050            Output = Result<language_model::LanguageModelToolUse, LanguageModelCompletionError>,
1051        >,
1052        cx: &mut Context<Self>,
1053    ) {
1054        self.diff = Diff::default();
1055        self.status = CodegenStatus::Pending;
1056
1057        self.generation = cx.spawn(async move |codegen, cx| {
1058            let finish_with_status = |status: CodegenStatus, cx: &mut AsyncApp| {
1059                let _ = codegen.update(cx, |this, cx| {
1060                    this.status = status;
1061                    cx.emit(CodegenEvent::Finished);
1062                    cx.notify();
1063                });
1064            };
1065
1066            let tool_use = tool_use.await;
1067
1068            match tool_use {
1069                Ok(tool_use) if tool_use.name.as_ref() == "rewrite_section" => {
1070                    // Parse the input JSON into RewriteSectionInput
1071                    match serde_json::from_value::<RewriteSectionInput>(tool_use.input) {
1072                        Ok(input) => {
1073                            // Store the description if non-empty
1074                            let description = if !input.description.trim().is_empty() {
1075                                Some(input.description.clone())
1076                            } else {
1077                                None
1078                            };
1079
1080                            // Apply the replacement text to the buffer and compute diff
1081                            let batch_diff_task = codegen
1082                                .update(cx, |this, cx| {
1083                                    this.model_explanation = description.map(Into::into);
1084                                    let range = this.range.clone();
1085                                    this.apply_edits(
1086                                        std::iter::once((range, input.replacement_text)),
1087                                        cx,
1088                                    );
1089                                    this.reapply_batch_diff(cx)
1090                                })
1091                                .ok();
1092
1093                            // Wait for the diff computation to complete
1094                            if let Some(diff_task) = batch_diff_task {
1095                                diff_task.await;
1096                            }
1097
1098                            finish_with_status(CodegenStatus::Done, cx);
1099                            return;
1100                        }
1101                        Err(e) => {
1102                            finish_with_status(CodegenStatus::Error(e.into()), cx);
1103                            return;
1104                        }
1105                    }
1106                }
1107                Ok(tool_use) if tool_use.name.as_ref() == "failure_message" => {
1108                    // Handle failure message tool use
1109                    match serde_json::from_value::<FailureMessageInput>(tool_use.input) {
1110                        Ok(input) => {
1111                            let _ = codegen.update(cx, |this, _cx| {
1112                                // Store the failure message as the tool description
1113                                this.model_explanation = Some(input.message.into());
1114                            });
1115                            finish_with_status(CodegenStatus::Done, cx);
1116                            return;
1117                        }
1118                        Err(e) => {
1119                            finish_with_status(CodegenStatus::Error(e.into()), cx);
1120                            return;
1121                        }
1122                    }
1123                }
1124                Ok(_tool_use) => {
1125                    // Unexpected tool.
1126                    finish_with_status(CodegenStatus::Done, cx);
1127                    return;
1128                }
1129                Err(e) => {
1130                    finish_with_status(CodegenStatus::Error(e.into()), cx);
1131                    return;
1132                }
1133            }
1134        });
1135        cx.notify();
1136    }
1137}
1138
1139#[derive(Copy, Clone, Debug)]
1140pub enum CodegenEvent {
1141    Finished,
1142    Undone,
1143}
1144
1145struct StripInvalidSpans<T> {
1146    stream: T,
1147    stream_done: bool,
1148    buffer: String,
1149    first_line: bool,
1150    line_end: bool,
1151    starts_with_code_block: bool,
1152}
1153
1154impl<T> StripInvalidSpans<T>
1155where
1156    T: Stream<Item = Result<String>>,
1157{
1158    fn new(stream: T) -> Self {
1159        Self {
1160            stream,
1161            stream_done: false,
1162            buffer: String::new(),
1163            first_line: true,
1164            line_end: false,
1165            starts_with_code_block: false,
1166        }
1167    }
1168}
1169
1170impl<T> Stream for StripInvalidSpans<T>
1171where
1172    T: Stream<Item = Result<String>>,
1173{
1174    type Item = Result<String>;
1175
1176    fn poll_next(self: Pin<&mut Self>, cx: &mut task::Context) -> Poll<Option<Self::Item>> {
1177        const CODE_BLOCK_DELIMITER: &str = "```";
1178        const CURSOR_SPAN: &str = "<|CURSOR|>";
1179
1180        let this = unsafe { self.get_unchecked_mut() };
1181        loop {
1182            if !this.stream_done {
1183                let mut stream = unsafe { Pin::new_unchecked(&mut this.stream) };
1184                match stream.as_mut().poll_next(cx) {
1185                    Poll::Ready(Some(Ok(chunk))) => {
1186                        this.buffer.push_str(&chunk);
1187                    }
1188                    Poll::Ready(Some(Err(error))) => return Poll::Ready(Some(Err(error))),
1189                    Poll::Ready(None) => {
1190                        this.stream_done = true;
1191                    }
1192                    Poll::Pending => return Poll::Pending,
1193                }
1194            }
1195
1196            let mut chunk = String::new();
1197            let mut consumed = 0;
1198            if !this.buffer.is_empty() {
1199                let mut lines = this.buffer.split('\n').enumerate().peekable();
1200                while let Some((line_ix, line)) = lines.next() {
1201                    if line_ix > 0 {
1202                        this.first_line = false;
1203                    }
1204
1205                    if this.first_line {
1206                        let trimmed_line = line.trim();
1207                        if lines.peek().is_some() {
1208                            if trimmed_line.starts_with(CODE_BLOCK_DELIMITER) {
1209                                consumed += line.len() + 1;
1210                                this.starts_with_code_block = true;
1211                                continue;
1212                            }
1213                        } else if trimmed_line.is_empty()
1214                            || prefixes(CODE_BLOCK_DELIMITER)
1215                                .any(|prefix| trimmed_line.starts_with(prefix))
1216                        {
1217                            break;
1218                        }
1219                    }
1220
1221                    let line_without_cursor = line.replace(CURSOR_SPAN, "");
1222                    if lines.peek().is_some() {
1223                        if this.line_end {
1224                            chunk.push('\n');
1225                        }
1226
1227                        chunk.push_str(&line_without_cursor);
1228                        this.line_end = true;
1229                        consumed += line.len() + 1;
1230                    } else if this.stream_done {
1231                        if !this.starts_with_code_block
1232                            || !line_without_cursor.trim().ends_with(CODE_BLOCK_DELIMITER)
1233                        {
1234                            if this.line_end {
1235                                chunk.push('\n');
1236                            }
1237
1238                            chunk.push_str(line);
1239                        }
1240
1241                        consumed += line.len();
1242                    } else {
1243                        let trimmed_line = line.trim();
1244                        if trimmed_line.is_empty()
1245                            || prefixes(CURSOR_SPAN).any(|prefix| trimmed_line.ends_with(prefix))
1246                            || prefixes(CODE_BLOCK_DELIMITER)
1247                                .any(|prefix| trimmed_line.ends_with(prefix))
1248                        {
1249                            break;
1250                        } else {
1251                            if this.line_end {
1252                                chunk.push('\n');
1253                                this.line_end = false;
1254                            }
1255
1256                            chunk.push_str(&line_without_cursor);
1257                            consumed += line.len();
1258                        }
1259                    }
1260                }
1261            }
1262
1263            this.buffer = this.buffer.split_off(consumed);
1264            if !chunk.is_empty() {
1265                return Poll::Ready(Some(Ok(chunk)));
1266            } else if this.stream_done {
1267                return Poll::Ready(None);
1268            }
1269        }
1270    }
1271}
1272
1273fn prefixes(text: &str) -> impl Iterator<Item = &str> {
1274    (0..text.len() - 1).map(|ix| &text[..ix + 1])
1275}
1276
1277#[derive(Default)]
1278pub struct Diff {
1279    pub deleted_row_ranges: Vec<(Anchor, RangeInclusive<u32>)>,
1280    pub inserted_row_ranges: Vec<Range<Anchor>>,
1281}
1282
1283impl Diff {
1284    fn is_empty(&self) -> bool {
1285        self.deleted_row_ranges.is_empty() && self.inserted_row_ranges.is_empty()
1286    }
1287}
1288
1289#[cfg(test)]
1290mod tests {
1291    use super::*;
1292    use futures::{
1293        Stream,
1294        stream::{self},
1295    };
1296    use gpui::TestAppContext;
1297    use indoc::indoc;
1298    use language::{Buffer, Point};
1299    use language_model::{LanguageModelRegistry, TokenUsage};
1300    use languages::rust_lang;
1301    use rand::prelude::*;
1302    use settings::SettingsStore;
1303    use std::{future, sync::Arc};
1304
1305    #[gpui::test(iterations = 10)]
1306    async fn test_transform_autoindent(cx: &mut TestAppContext, mut rng: StdRng) {
1307        init_test(cx);
1308
1309        let text = indoc! {"
1310            fn main() {
1311                let x = 0;
1312                for _ in 0..10 {
1313                    x += 1;
1314                }
1315            }
1316        "};
1317        let buffer = cx.new(|cx| Buffer::local(text, cx).with_language(rust_lang(), cx));
1318        let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1319        let range = buffer.read_with(cx, |buffer, cx| {
1320            let snapshot = buffer.snapshot(cx);
1321            snapshot.anchor_before(Point::new(1, 0))..snapshot.anchor_after(Point::new(4, 5))
1322        });
1323        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
1324        let codegen = cx.new(|cx| {
1325            CodegenAlternative::new(
1326                buffer.clone(),
1327                range.clone(),
1328                true,
1329                None,
1330                prompt_builder,
1331                cx,
1332            )
1333        });
1334
1335        let chunks_tx = simulate_response_stream(&codegen, cx);
1336
1337        let mut new_text = concat!(
1338            "       let mut x = 0;\n",
1339            "       while x < 10 {\n",
1340            "           x += 1;\n",
1341            "       }",
1342        );
1343        while !new_text.is_empty() {
1344            let max_len = cmp::min(new_text.len(), 10);
1345            let len = rng.random_range(1..=max_len);
1346            let (chunk, suffix) = new_text.split_at(len);
1347            chunks_tx.unbounded_send(chunk.to_string()).unwrap();
1348            new_text = suffix;
1349            cx.background_executor.run_until_parked();
1350        }
1351        drop(chunks_tx);
1352        cx.background_executor.run_until_parked();
1353
1354        assert_eq!(
1355            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1356            indoc! {"
1357                fn main() {
1358                    let mut x = 0;
1359                    while x < 10 {
1360                        x += 1;
1361                    }
1362                }
1363            "}
1364        );
1365    }
1366
1367    #[gpui::test(iterations = 10)]
1368    async fn test_autoindent_when_generating_past_indentation(
1369        cx: &mut TestAppContext,
1370        mut rng: StdRng,
1371    ) {
1372        init_test(cx);
1373
1374        let text = indoc! {"
1375            fn main() {
1376                le
1377            }
1378        "};
1379        let buffer = cx.new(|cx| Buffer::local(text, cx).with_language(rust_lang(), cx));
1380        let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1381        let range = buffer.read_with(cx, |buffer, cx| {
1382            let snapshot = buffer.snapshot(cx);
1383            snapshot.anchor_before(Point::new(1, 6))..snapshot.anchor_after(Point::new(1, 6))
1384        });
1385        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
1386        let codegen = cx.new(|cx| {
1387            CodegenAlternative::new(
1388                buffer.clone(),
1389                range.clone(),
1390                true,
1391                None,
1392                prompt_builder,
1393                cx,
1394            )
1395        });
1396
1397        let chunks_tx = simulate_response_stream(&codegen, cx);
1398
1399        cx.background_executor.run_until_parked();
1400
1401        let mut new_text = concat!(
1402            "t mut x = 0;\n",
1403            "while x < 10 {\n",
1404            "    x += 1;\n",
1405            "}", //
1406        );
1407        while !new_text.is_empty() {
1408            let max_len = cmp::min(new_text.len(), 10);
1409            let len = rng.random_range(1..=max_len);
1410            let (chunk, suffix) = new_text.split_at(len);
1411            chunks_tx.unbounded_send(chunk.to_string()).unwrap();
1412            new_text = suffix;
1413            cx.background_executor.run_until_parked();
1414        }
1415        drop(chunks_tx);
1416        cx.background_executor.run_until_parked();
1417
1418        assert_eq!(
1419            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1420            indoc! {"
1421                fn main() {
1422                    let mut x = 0;
1423                    while x < 10 {
1424                        x += 1;
1425                    }
1426                }
1427            "}
1428        );
1429    }
1430
1431    #[gpui::test(iterations = 10)]
1432    async fn test_autoindent_when_generating_before_indentation(
1433        cx: &mut TestAppContext,
1434        mut rng: StdRng,
1435    ) {
1436        init_test(cx);
1437
1438        let text = concat!(
1439            "fn main() {\n",
1440            "  \n",
1441            "}\n" //
1442        );
1443        let buffer = cx.new(|cx| Buffer::local(text, cx).with_language(rust_lang(), cx));
1444        let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1445        let range = buffer.read_with(cx, |buffer, cx| {
1446            let snapshot = buffer.snapshot(cx);
1447            snapshot.anchor_before(Point::new(1, 2))..snapshot.anchor_after(Point::new(1, 2))
1448        });
1449        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
1450        let codegen = cx.new(|cx| {
1451            CodegenAlternative::new(
1452                buffer.clone(),
1453                range.clone(),
1454                true,
1455                None,
1456                prompt_builder,
1457                cx,
1458            )
1459        });
1460
1461        let chunks_tx = simulate_response_stream(&codegen, cx);
1462
1463        cx.background_executor.run_until_parked();
1464
1465        let mut new_text = concat!(
1466            "let mut x = 0;\n",
1467            "while x < 10 {\n",
1468            "    x += 1;\n",
1469            "}", //
1470        );
1471        while !new_text.is_empty() {
1472            let max_len = cmp::min(new_text.len(), 10);
1473            let len = rng.random_range(1..=max_len);
1474            let (chunk, suffix) = new_text.split_at(len);
1475            chunks_tx.unbounded_send(chunk.to_string()).unwrap();
1476            new_text = suffix;
1477            cx.background_executor.run_until_parked();
1478        }
1479        drop(chunks_tx);
1480        cx.background_executor.run_until_parked();
1481
1482        assert_eq!(
1483            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1484            indoc! {"
1485                fn main() {
1486                    let mut x = 0;
1487                    while x < 10 {
1488                        x += 1;
1489                    }
1490                }
1491            "}
1492        );
1493    }
1494
1495    #[gpui::test(iterations = 10)]
1496    async fn test_autoindent_respects_tabs_in_selection(cx: &mut TestAppContext) {
1497        init_test(cx);
1498
1499        let text = indoc! {"
1500            func main() {
1501            \tx := 0
1502            \tfor i := 0; i < 10; i++ {
1503            \t\tx++
1504            \t}
1505            }
1506        "};
1507        let buffer = cx.new(|cx| Buffer::local(text, cx));
1508        let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1509        let range = buffer.read_with(cx, |buffer, cx| {
1510            let snapshot = buffer.snapshot(cx);
1511            snapshot.anchor_before(Point::new(0, 0))..snapshot.anchor_after(Point::new(4, 2))
1512        });
1513        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
1514        let codegen = cx.new(|cx| {
1515            CodegenAlternative::new(
1516                buffer.clone(),
1517                range.clone(),
1518                true,
1519                None,
1520                prompt_builder,
1521                cx,
1522            )
1523        });
1524
1525        let chunks_tx = simulate_response_stream(&codegen, cx);
1526        let new_text = concat!(
1527            "func main() {\n",
1528            "\tx := 0\n",
1529            "\tfor x < 10 {\n",
1530            "\t\tx++\n",
1531            "\t}", //
1532        );
1533        chunks_tx.unbounded_send(new_text.to_string()).unwrap();
1534        drop(chunks_tx);
1535        cx.background_executor.run_until_parked();
1536
1537        assert_eq!(
1538            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1539            indoc! {"
1540                func main() {
1541                \tx := 0
1542                \tfor x < 10 {
1543                \t\tx++
1544                \t}
1545                }
1546            "}
1547        );
1548    }
1549
1550    #[gpui::test]
1551    async fn test_inactive_codegen_alternative(cx: &mut TestAppContext) {
1552        init_test(cx);
1553
1554        let text = indoc! {"
1555            fn main() {
1556                let x = 0;
1557            }
1558        "};
1559        let buffer = cx.new(|cx| Buffer::local(text, cx).with_language(rust_lang(), cx));
1560        let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1561        let range = buffer.read_with(cx, |buffer, cx| {
1562            let snapshot = buffer.snapshot(cx);
1563            snapshot.anchor_before(Point::new(1, 0))..snapshot.anchor_after(Point::new(1, 14))
1564        });
1565        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
1566        let codegen = cx.new(|cx| {
1567            CodegenAlternative::new(
1568                buffer.clone(),
1569                range.clone(),
1570                false,
1571                None,
1572                prompt_builder,
1573                cx,
1574            )
1575        });
1576
1577        let chunks_tx = simulate_response_stream(&codegen, cx);
1578        chunks_tx
1579            .unbounded_send("let mut x = 0;\nx += 1;".to_string())
1580            .unwrap();
1581        drop(chunks_tx);
1582        cx.run_until_parked();
1583
1584        // The codegen is inactive, so the buffer doesn't get modified.
1585        assert_eq!(
1586            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1587            text
1588        );
1589
1590        // Activating the codegen applies the changes.
1591        codegen.update(cx, |codegen, cx| codegen.set_active(true, cx));
1592        assert_eq!(
1593            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1594            indoc! {"
1595                fn main() {
1596                    let mut x = 0;
1597                    x += 1;
1598                }
1599            "}
1600        );
1601
1602        // Deactivating the codegen undoes the changes.
1603        codegen.update(cx, |codegen, cx| codegen.set_active(false, cx));
1604        cx.run_until_parked();
1605        assert_eq!(
1606            buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx).text()),
1607            text
1608        );
1609    }
1610
1611    #[gpui::test]
1612    async fn test_strip_invalid_spans_from_codeblock() {
1613        assert_chunks("Lorem ipsum dolor", "Lorem ipsum dolor").await;
1614        assert_chunks("```\nLorem ipsum dolor", "Lorem ipsum dolor").await;
1615        assert_chunks("```\nLorem ipsum dolor\n```", "Lorem ipsum dolor").await;
1616        assert_chunks(
1617            "```html\n```js\nLorem ipsum dolor\n```\n```",
1618            "```js\nLorem ipsum dolor\n```",
1619        )
1620        .await;
1621        assert_chunks("``\nLorem ipsum dolor\n```", "``\nLorem ipsum dolor\n```").await;
1622        assert_chunks("Lorem<|CURSOR|> ipsum", "Lorem ipsum").await;
1623        assert_chunks("Lorem ipsum", "Lorem ipsum").await;
1624        assert_chunks("```\n<|CURSOR|>Lorem ipsum\n```", "Lorem ipsum").await;
1625
1626        async fn assert_chunks(text: &str, expected_text: &str) {
1627            for chunk_size in 1..=text.len() {
1628                let actual_text = StripInvalidSpans::new(chunks(text, chunk_size))
1629                    .map(|chunk| chunk.unwrap())
1630                    .collect::<String>()
1631                    .await;
1632                assert_eq!(
1633                    actual_text, expected_text,
1634                    "failed to strip invalid spans, chunk size: {}",
1635                    chunk_size
1636                );
1637            }
1638        }
1639
1640        fn chunks(text: &str, size: usize) -> impl Stream<Item = Result<String>> {
1641            stream::iter(
1642                text.chars()
1643                    .collect::<Vec<_>>()
1644                    .chunks(size)
1645                    .map(|chunk| Ok(chunk.iter().collect::<String>()))
1646                    .collect::<Vec<_>>(),
1647            )
1648        }
1649    }
1650
1651    fn init_test(cx: &mut TestAppContext) {
1652        cx.update(LanguageModelRegistry::test);
1653        cx.set_global(cx.update(SettingsStore::test));
1654    }
1655
1656    fn simulate_response_stream(
1657        codegen: &Entity<CodegenAlternative>,
1658        cx: &mut TestAppContext,
1659    ) -> mpsc::UnboundedSender<String> {
1660        let (chunks_tx, chunks_rx) = mpsc::unbounded();
1661        codegen.update(cx, |codegen, cx| {
1662            codegen.handle_stream(
1663                String::new(),
1664                String::new(),
1665                None,
1666                future::ready(Ok(LanguageModelTextStream {
1667                    message_id: None,
1668                    stream: chunks_rx.map(Ok).boxed(),
1669                    last_token_usage: Arc::new(Mutex::new(TokenUsage::default())),
1670                })),
1671                cx,
1672            );
1673        });
1674        chunks_tx
1675    }
1676}