1mod dragged_item_receiver;
   2
   3use super::{ItemHandle, SplitDirection};
   4use crate::{
   5    dock::{icon_for_dock_anchor, AnchorDockBottom, AnchorDockRight, ExpandDock, HideDock},
   6    item::WeakItemHandle,
   7    toolbar::Toolbar,
   8    Item, NewFile, NewSearch, NewTerminal, Workspace,
   9};
  10use anyhow::Result;
  11use collections::{HashMap, HashSet, VecDeque};
  12use context_menu::{ContextMenu, ContextMenuItem};
  13use drag_and_drop::Draggable;
  14pub use dragged_item_receiver::{dragged_item_receiver, handle_dropped_item};
  15use futures::StreamExt;
  16use gpui::{
  17    actions,
  18    elements::*,
  19    geometry::{
  20        rect::RectF,
  21        vector::{vec2f, Vector2F},
  22    },
  23    impl_actions, impl_internal_actions,
  24    keymap_matcher::KeymapContext,
  25    platform::{CursorStyle, MouseButton, NavigationDirection, PromptLevel},
  26    Action, AnyViewHandle, AnyWeakViewHandle, AppContext, AsyncAppContext, Entity, EventContext,
  27    ModelHandle, MouseRegion, Quad, Task, View, ViewContext, ViewHandle, WeakViewHandle,
  28};
  29use project::{Project, ProjectEntryId, ProjectPath};
  30use serde::Deserialize;
  31use settings::{Autosave, DockAnchor, Settings};
  32use std::{any::Any, cell::RefCell, cmp, mem, path::Path, rc::Rc};
  33use theme::Theme;
  34use util::ResultExt;
  35
  36#[derive(Clone, Deserialize, PartialEq)]
  37pub struct ActivateItem(pub usize);
  38
  39actions!(
  40    pane,
  41    [
  42        ActivatePrevItem,
  43        ActivateNextItem,
  44        ActivateLastItem,
  45        CloseActiveItem,
  46        CloseInactiveItems,
  47        CloseCleanItems,
  48        CloseItemsToTheLeft,
  49        CloseItemsToTheRight,
  50        CloseAllItems,
  51        ReopenClosedItem,
  52        SplitLeft,
  53        SplitUp,
  54        SplitRight,
  55        SplitDown,
  56    ]
  57);
  58
  59#[derive(Clone, PartialEq)]
  60pub struct CloseItem {
  61    pub item_id: usize,
  62    pub pane: WeakViewHandle<Pane>,
  63}
  64
  65#[derive(Clone, PartialEq)]
  66pub struct MoveItem {
  67    pub item_id: usize,
  68    pub from: WeakViewHandle<Pane>,
  69    pub to: WeakViewHandle<Pane>,
  70    pub destination_index: usize,
  71}
  72
  73#[derive(Clone, Deserialize, PartialEq)]
  74pub struct GoBack {
  75    #[serde(skip_deserializing)]
  76    pub pane: Option<WeakViewHandle<Pane>>,
  77}
  78
  79#[derive(Clone, Deserialize, PartialEq)]
  80pub struct GoForward {
  81    #[serde(skip_deserializing)]
  82    pub pane: Option<WeakViewHandle<Pane>>,
  83}
  84
  85#[derive(Clone, PartialEq)]
  86pub struct DeploySplitMenu;
  87
  88#[derive(Clone, PartialEq)]
  89pub struct DeployDockMenu;
  90
  91#[derive(Clone, PartialEq)]
  92pub struct DeployNewMenu;
  93
  94impl_actions!(pane, [GoBack, GoForward, ActivateItem]);
  95impl_internal_actions!(
  96    pane,
  97    [
  98        CloseItem,
  99        DeploySplitMenu,
 100        DeployNewMenu,
 101        DeployDockMenu,
 102        MoveItem
 103    ]
 104);
 105
 106const MAX_NAVIGATION_HISTORY_LEN: usize = 1024;
 107
 108pub type BackgroundActions = fn() -> &'static [(&'static str, &'static dyn Action)];
 109
 110pub fn init(cx: &mut AppContext) {
 111    cx.add_action(|pane: &mut Pane, action: &ActivateItem, cx| {
 112        pane.activate_item(action.0, true, true, cx);
 113    });
 114    cx.add_action(|pane: &mut Pane, _: &ActivateLastItem, cx| {
 115        pane.activate_item(pane.items.len() - 1, true, true, cx);
 116    });
 117    cx.add_action(|pane: &mut Pane, _: &ActivatePrevItem, cx| {
 118        pane.activate_prev_item(true, cx);
 119    });
 120    cx.add_action(|pane: &mut Pane, _: &ActivateNextItem, cx| {
 121        pane.activate_next_item(true, cx);
 122    });
 123    cx.add_async_action(Pane::close_active_item);
 124    cx.add_async_action(Pane::close_inactive_items);
 125    cx.add_async_action(Pane::close_clean_items);
 126    cx.add_async_action(Pane::close_items_to_the_left);
 127    cx.add_async_action(Pane::close_items_to_the_right);
 128    cx.add_async_action(Pane::close_all_items);
 129    cx.add_async_action(|workspace: &mut Workspace, action: &CloseItem, cx| {
 130        let pane = action.pane.upgrade(cx)?;
 131        let task = Pane::close_item(workspace, pane, action.item_id, cx);
 132        Some(cx.foreground().spawn(async move {
 133            task.await?;
 134            Ok(())
 135        }))
 136    });
 137    cx.add_action(
 138        |workspace,
 139         MoveItem {
 140             from,
 141             to,
 142             item_id,
 143             destination_index,
 144         },
 145         cx| {
 146            // Get item handle to move
 147            let from = if let Some(from) = from.upgrade(cx) {
 148                from
 149            } else {
 150                return;
 151            };
 152
 153            // Add item to new pane at given index
 154            let to = if let Some(to) = to.upgrade(cx) {
 155                to
 156            } else {
 157                return;
 158            };
 159
 160            Pane::move_item(workspace, from, to, *item_id, *destination_index, cx)
 161        },
 162    );
 163    cx.add_action(|pane: &mut Pane, _: &SplitLeft, cx| pane.split(SplitDirection::Left, cx));
 164    cx.add_action(|pane: &mut Pane, _: &SplitUp, cx| pane.split(SplitDirection::Up, cx));
 165    cx.add_action(|pane: &mut Pane, _: &SplitRight, cx| pane.split(SplitDirection::Right, cx));
 166    cx.add_action(|pane: &mut Pane, _: &SplitDown, cx| pane.split(SplitDirection::Down, cx));
 167    cx.add_action(Pane::deploy_split_menu);
 168    cx.add_action(Pane::deploy_dock_menu);
 169    cx.add_action(Pane::deploy_new_menu);
 170    cx.add_action(|workspace: &mut Workspace, _: &ReopenClosedItem, cx| {
 171        Pane::reopen_closed_item(workspace, cx).detach();
 172    });
 173    cx.add_action(|workspace: &mut Workspace, action: &GoBack, cx| {
 174        Pane::go_back(
 175            workspace,
 176            action
 177                .pane
 178                .as_ref()
 179                .and_then(|weak_handle| weak_handle.upgrade(cx)),
 180            cx,
 181        )
 182        .detach();
 183    });
 184    cx.add_action(|workspace: &mut Workspace, action: &GoForward, cx| {
 185        Pane::go_forward(
 186            workspace,
 187            action
 188                .pane
 189                .as_ref()
 190                .and_then(|weak_handle| weak_handle.upgrade(cx)),
 191            cx,
 192        )
 193        .detach();
 194    });
 195}
 196
 197#[derive(Debug)]
 198pub enum Event {
 199    ActivateItem { local: bool },
 200    Remove,
 201    RemoveItem { item_id: usize },
 202    Split(SplitDirection),
 203    ChangeItemTitle,
 204}
 205
 206pub struct Pane {
 207    items: Vec<Box<dyn ItemHandle>>,
 208    activation_history: Vec<usize>,
 209    is_active: bool,
 210    active_item_index: usize,
 211    last_focused_view_by_item: HashMap<usize, AnyWeakViewHandle>,
 212    autoscroll: bool,
 213    nav_history: Rc<RefCell<NavHistory>>,
 214    toolbar: ViewHandle<Toolbar>,
 215    tab_bar_context_menu: TabBarContextMenu,
 216    docked: Option<DockAnchor>,
 217    _background_actions: BackgroundActions,
 218    _workspace_id: usize,
 219}
 220
 221pub struct ItemNavHistory {
 222    history: Rc<RefCell<NavHistory>>,
 223    item: Rc<dyn WeakItemHandle>,
 224}
 225
 226struct NavHistory {
 227    mode: NavigationMode,
 228    backward_stack: VecDeque<NavigationEntry>,
 229    forward_stack: VecDeque<NavigationEntry>,
 230    closed_stack: VecDeque<NavigationEntry>,
 231    paths_by_item: HashMap<usize, ProjectPath>,
 232    pane: WeakViewHandle<Pane>,
 233}
 234
 235#[derive(Copy, Clone)]
 236enum NavigationMode {
 237    Normal,
 238    GoingBack,
 239    GoingForward,
 240    ClosingItem,
 241    ReopeningClosedItem,
 242    Disabled,
 243}
 244
 245impl Default for NavigationMode {
 246    fn default() -> Self {
 247        Self::Normal
 248    }
 249}
 250
 251pub struct NavigationEntry {
 252    pub item: Rc<dyn WeakItemHandle>,
 253    pub data: Option<Box<dyn Any>>,
 254}
 255
 256struct DraggedItem {
 257    item: Box<dyn ItemHandle>,
 258    pane: WeakViewHandle<Pane>,
 259}
 260
 261pub enum ReorderBehavior {
 262    None,
 263    MoveAfterActive,
 264    MoveToIndex(usize),
 265}
 266
 267#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 268enum TabBarContextMenuKind {
 269    New,
 270    Split,
 271    Dock,
 272}
 273
 274struct TabBarContextMenu {
 275    kind: TabBarContextMenuKind,
 276    handle: ViewHandle<ContextMenu>,
 277}
 278
 279impl TabBarContextMenu {
 280    fn handle_if_kind(&self, kind: TabBarContextMenuKind) -> Option<ViewHandle<ContextMenu>> {
 281        if self.kind == kind {
 282            return Some(self.handle.clone());
 283        }
 284        None
 285    }
 286}
 287
 288impl Pane {
 289    pub fn new(
 290        workspace_id: usize,
 291        docked: Option<DockAnchor>,
 292        background_actions: BackgroundActions,
 293        cx: &mut ViewContext<Self>,
 294    ) -> Self {
 295        let handle = cx.weak_handle();
 296        let context_menu = cx.add_view(ContextMenu::new);
 297        context_menu.update(cx, |menu, _| {
 298            menu.set_position_mode(OverlayPositionMode::Local)
 299        });
 300
 301        Self {
 302            items: Vec::new(),
 303            activation_history: Vec::new(),
 304            is_active: true,
 305            active_item_index: 0,
 306            last_focused_view_by_item: Default::default(),
 307            autoscroll: false,
 308            nav_history: Rc::new(RefCell::new(NavHistory {
 309                mode: NavigationMode::Normal,
 310                backward_stack: Default::default(),
 311                forward_stack: Default::default(),
 312                closed_stack: Default::default(),
 313                paths_by_item: Default::default(),
 314                pane: handle.clone(),
 315            })),
 316            toolbar: cx.add_view(|_| Toolbar::new(handle)),
 317            tab_bar_context_menu: TabBarContextMenu {
 318                kind: TabBarContextMenuKind::New,
 319                handle: context_menu,
 320            },
 321            docked,
 322            _background_actions: background_actions,
 323            _workspace_id: workspace_id,
 324        }
 325    }
 326
 327    pub fn is_active(&self) -> bool {
 328        self.is_active
 329    }
 330
 331    pub fn set_active(&mut self, is_active: bool, cx: &mut ViewContext<Self>) {
 332        self.is_active = is_active;
 333        cx.notify();
 334    }
 335
 336    pub fn set_docked(&mut self, docked: Option<DockAnchor>, cx: &mut ViewContext<Self>) {
 337        self.docked = docked;
 338        cx.notify();
 339    }
 340
 341    pub fn nav_history_for_item<T: Item>(&self, item: &ViewHandle<T>) -> ItemNavHistory {
 342        ItemNavHistory {
 343            history: self.nav_history.clone(),
 344            item: Rc::new(item.downgrade()),
 345        }
 346    }
 347
 348    pub fn go_back(
 349        workspace: &mut Workspace,
 350        pane: Option<ViewHandle<Pane>>,
 351        cx: &mut ViewContext<Workspace>,
 352    ) -> Task<()> {
 353        Self::navigate_history(
 354            workspace,
 355            pane.unwrap_or_else(|| workspace.active_pane().clone()),
 356            NavigationMode::GoingBack,
 357            cx,
 358        )
 359    }
 360
 361    pub fn go_forward(
 362        workspace: &mut Workspace,
 363        pane: Option<ViewHandle<Pane>>,
 364        cx: &mut ViewContext<Workspace>,
 365    ) -> Task<()> {
 366        Self::navigate_history(
 367            workspace,
 368            pane.unwrap_or_else(|| workspace.active_pane().clone()),
 369            NavigationMode::GoingForward,
 370            cx,
 371        )
 372    }
 373
 374    pub fn reopen_closed_item(
 375        workspace: &mut Workspace,
 376        cx: &mut ViewContext<Workspace>,
 377    ) -> Task<()> {
 378        Self::navigate_history(
 379            workspace,
 380            workspace.active_pane().clone(),
 381            NavigationMode::ReopeningClosedItem,
 382            cx,
 383        )
 384    }
 385
 386    pub fn disable_history(&mut self) {
 387        self.nav_history.borrow_mut().disable();
 388    }
 389
 390    pub fn enable_history(&mut self) {
 391        self.nav_history.borrow_mut().enable();
 392    }
 393
 394    pub fn can_navigate_backward(&self) -> bool {
 395        !self.nav_history.borrow().backward_stack.is_empty()
 396    }
 397
 398    pub fn can_navigate_forward(&self) -> bool {
 399        !self.nav_history.borrow().forward_stack.is_empty()
 400    }
 401
 402    fn history_updated(&mut self, cx: &mut ViewContext<Self>) {
 403        self.toolbar.update(cx, |_, cx| cx.notify());
 404    }
 405
 406    fn navigate_history(
 407        workspace: &mut Workspace,
 408        pane: ViewHandle<Pane>,
 409        mode: NavigationMode,
 410        cx: &mut ViewContext<Workspace>,
 411    ) -> Task<()> {
 412        cx.focus(&pane);
 413
 414        let to_load = pane.update(cx, |pane, cx| {
 415            loop {
 416                // Retrieve the weak item handle from the history.
 417                let entry = pane.nav_history.borrow_mut().pop(mode, cx)?;
 418
 419                // If the item is still present in this pane, then activate it.
 420                if let Some(index) = entry
 421                    .item
 422                    .upgrade(cx)
 423                    .and_then(|v| pane.index_for_item(v.as_ref()))
 424                {
 425                    let prev_active_item_index = pane.active_item_index;
 426                    pane.nav_history.borrow_mut().set_mode(mode);
 427                    pane.activate_item(index, true, true, cx);
 428                    pane.nav_history
 429                        .borrow_mut()
 430                        .set_mode(NavigationMode::Normal);
 431
 432                    let mut navigated = prev_active_item_index != pane.active_item_index;
 433                    if let Some(data) = entry.data {
 434                        navigated |= pane.active_item()?.navigate(data, cx);
 435                    }
 436
 437                    if navigated {
 438                        break None;
 439                    }
 440                }
 441                // If the item is no longer present in this pane, then retrieve its
 442                // project path in order to reopen it.
 443                else {
 444                    break pane
 445                        .nav_history
 446                        .borrow()
 447                        .paths_by_item
 448                        .get(&entry.item.id())
 449                        .cloned()
 450                        .map(|project_path| (project_path, entry));
 451                }
 452            }
 453        });
 454
 455        if let Some((project_path, entry)) = to_load {
 456            // If the item was no longer present, then load it again from its previous path.
 457            let pane = pane.downgrade();
 458            let task = workspace.load_path(project_path, cx);
 459            cx.spawn(|workspace, mut cx| async move {
 460                let task = task.await;
 461                if let Some(pane) = pane.upgrade(&cx) {
 462                    let mut navigated = false;
 463                    if let Some((project_entry_id, build_item)) = task.log_err() {
 464                        let prev_active_item_id = pane.update(&mut cx, |pane, _| {
 465                            pane.nav_history.borrow_mut().set_mode(mode);
 466                            pane.active_item().map(|p| p.id())
 467                        });
 468
 469                        let item = workspace.update(&mut cx, |workspace, cx| {
 470                            Self::open_item(
 471                                workspace,
 472                                pane.clone(),
 473                                project_entry_id,
 474                                true,
 475                                cx,
 476                                build_item,
 477                            )
 478                        });
 479
 480                        pane.update(&mut cx, |pane, cx| {
 481                            navigated |= Some(item.id()) != prev_active_item_id;
 482                            pane.nav_history
 483                                .borrow_mut()
 484                                .set_mode(NavigationMode::Normal);
 485                            if let Some(data) = entry.data {
 486                                navigated |= item.navigate(data, cx);
 487                            }
 488                        });
 489                    }
 490
 491                    if !navigated {
 492                        workspace
 493                            .update(&mut cx, |workspace, cx| {
 494                                Self::navigate_history(workspace, pane, mode, cx)
 495                            })
 496                            .await;
 497                    }
 498                }
 499            })
 500        } else {
 501            Task::ready(())
 502        }
 503    }
 504
 505    pub(crate) fn open_item(
 506        workspace: &mut Workspace,
 507        pane: ViewHandle<Pane>,
 508        project_entry_id: ProjectEntryId,
 509        focus_item: bool,
 510        cx: &mut ViewContext<Workspace>,
 511        build_item: impl FnOnce(&mut ViewContext<Pane>) -> Box<dyn ItemHandle>,
 512    ) -> Box<dyn ItemHandle> {
 513        let existing_item = pane.update(cx, |pane, cx| {
 514            for (index, item) in pane.items.iter().enumerate() {
 515                if item.is_singleton(cx)
 516                    && item.project_entry_ids(cx).as_slice() == [project_entry_id]
 517                {
 518                    let item = item.boxed_clone();
 519                    return Some((index, item));
 520                }
 521            }
 522            None
 523        });
 524
 525        if let Some((index, existing_item)) = existing_item {
 526            pane.update(cx, |pane, cx| {
 527                pane.activate_item(index, focus_item, focus_item, cx);
 528            });
 529            existing_item
 530        } else {
 531            let new_item = pane.update(cx, |_, cx| build_item(cx));
 532            Pane::add_item(
 533                workspace,
 534                &pane,
 535                new_item.clone(),
 536                true,
 537                focus_item,
 538                None,
 539                cx,
 540            );
 541            new_item
 542        }
 543    }
 544
 545    pub(crate) fn add_item(
 546        workspace: &mut Workspace,
 547        pane: &ViewHandle<Pane>,
 548        item: Box<dyn ItemHandle>,
 549        activate_pane: bool,
 550        focus_item: bool,
 551        destination_index: Option<usize>,
 552        cx: &mut ViewContext<Workspace>,
 553    ) {
 554        // If no destination index is specified, add or move the item after the active item.
 555        let mut insertion_index = {
 556            let pane = pane.read(cx);
 557            cmp::min(
 558                if let Some(destination_index) = destination_index {
 559                    destination_index
 560                } else {
 561                    pane.active_item_index + 1
 562                },
 563                pane.items.len(),
 564            )
 565        };
 566
 567        item.added_to_pane(workspace, pane.clone(), cx);
 568
 569        // Does the item already exist?
 570        let project_entry_id = if item.is_singleton(cx) {
 571            item.project_entry_ids(cx).get(0).copied()
 572        } else {
 573            None
 574        };
 575
 576        let existing_item_index = pane.read(cx).items.iter().position(|existing_item| {
 577            if existing_item.id() == item.id() {
 578                true
 579            } else if existing_item.is_singleton(cx) {
 580                existing_item
 581                    .project_entry_ids(cx)
 582                    .get(0)
 583                    .map_or(false, |existing_entry_id| {
 584                        Some(existing_entry_id) == project_entry_id.as_ref()
 585                    })
 586            } else {
 587                false
 588            }
 589        });
 590
 591        if let Some(existing_item_index) = existing_item_index {
 592            // If the item already exists, move it to the desired destination and activate it
 593            pane.update(cx, |pane, cx| {
 594                if existing_item_index != insertion_index {
 595                    cx.reparent(item.as_any());
 596                    let existing_item_is_active = existing_item_index == pane.active_item_index;
 597
 598                    // If the caller didn't specify a destination and the added item is already
 599                    // the active one, don't move it
 600                    if existing_item_is_active && destination_index.is_none() {
 601                        insertion_index = existing_item_index;
 602                    } else {
 603                        pane.items.remove(existing_item_index);
 604                        if existing_item_index < pane.active_item_index {
 605                            pane.active_item_index -= 1;
 606                        }
 607                        insertion_index = insertion_index.min(pane.items.len());
 608
 609                        pane.items.insert(insertion_index, item.clone());
 610
 611                        if existing_item_is_active {
 612                            pane.active_item_index = insertion_index;
 613                        } else if insertion_index <= pane.active_item_index {
 614                            pane.active_item_index += 1;
 615                        }
 616                    }
 617
 618                    cx.notify();
 619                }
 620
 621                pane.activate_item(insertion_index, activate_pane, focus_item, cx);
 622            });
 623        } else {
 624            pane.update(cx, |pane, cx| {
 625                cx.reparent(item.as_any());
 626                pane.items.insert(insertion_index, item);
 627                if insertion_index <= pane.active_item_index {
 628                    pane.active_item_index += 1;
 629                }
 630
 631                pane.activate_item(insertion_index, activate_pane, focus_item, cx);
 632                cx.notify();
 633            });
 634        }
 635    }
 636
 637    pub fn items_len(&self) -> usize {
 638        self.items.len()
 639    }
 640
 641    pub fn items(&self) -> impl Iterator<Item = &Box<dyn ItemHandle>> + DoubleEndedIterator {
 642        self.items.iter()
 643    }
 644
 645    pub fn items_of_type<T: View>(&self) -> impl '_ + Iterator<Item = ViewHandle<T>> {
 646        self.items
 647            .iter()
 648            .filter_map(|item| item.as_any().clone().downcast())
 649    }
 650
 651    pub fn active_item(&self) -> Option<Box<dyn ItemHandle>> {
 652        self.items.get(self.active_item_index).cloned()
 653    }
 654
 655    pub fn item_for_entry(
 656        &self,
 657        entry_id: ProjectEntryId,
 658        cx: &AppContext,
 659    ) -> Option<Box<dyn ItemHandle>> {
 660        self.items.iter().find_map(|item| {
 661            if item.is_singleton(cx) && item.project_entry_ids(cx).as_slice() == [entry_id] {
 662                Some(item.boxed_clone())
 663            } else {
 664                None
 665            }
 666        })
 667    }
 668
 669    pub fn index_for_item(&self, item: &dyn ItemHandle) -> Option<usize> {
 670        self.items.iter().position(|i| i.id() == item.id())
 671    }
 672
 673    pub fn activate_item(
 674        &mut self,
 675        index: usize,
 676        activate_pane: bool,
 677        focus_item: bool,
 678        cx: &mut ViewContext<Self>,
 679    ) {
 680        use NavigationMode::{GoingBack, GoingForward};
 681
 682        if index < self.items.len() {
 683            let prev_active_item_ix = mem::replace(&mut self.active_item_index, index);
 684            if prev_active_item_ix != self.active_item_index
 685                || matches!(self.nav_history.borrow().mode, GoingBack | GoingForward)
 686            {
 687                if let Some(prev_item) = self.items.get(prev_active_item_ix) {
 688                    prev_item.deactivated(cx);
 689                }
 690
 691                cx.emit(Event::ActivateItem {
 692                    local: activate_pane,
 693                });
 694            }
 695
 696            if let Some(newly_active_item) = self.items.get(index) {
 697                self.activation_history
 698                    .retain(|&previously_active_item_id| {
 699                        previously_active_item_id != newly_active_item.id()
 700                    });
 701                self.activation_history.push(newly_active_item.id());
 702            }
 703
 704            self.update_toolbar(cx);
 705
 706            if focus_item {
 707                self.focus_active_item(cx);
 708            }
 709
 710            self.autoscroll = true;
 711            cx.notify();
 712        }
 713    }
 714
 715    pub fn activate_prev_item(&mut self, activate_pane: bool, cx: &mut ViewContext<Self>) {
 716        let mut index = self.active_item_index;
 717        if index > 0 {
 718            index -= 1;
 719        } else if !self.items.is_empty() {
 720            index = self.items.len() - 1;
 721        }
 722        self.activate_item(index, activate_pane, activate_pane, cx);
 723    }
 724
 725    pub fn activate_next_item(&mut self, activate_pane: bool, cx: &mut ViewContext<Self>) {
 726        let mut index = self.active_item_index;
 727        if index + 1 < self.items.len() {
 728            index += 1;
 729        } else {
 730            index = 0;
 731        }
 732        self.activate_item(index, activate_pane, activate_pane, cx);
 733    }
 734
 735    pub fn close_active_item(
 736        workspace: &mut Workspace,
 737        _: &CloseActiveItem,
 738        cx: &mut ViewContext<Workspace>,
 739    ) -> Option<Task<Result<()>>> {
 740        let pane_handle = workspace.active_pane().clone();
 741        let pane = pane_handle.read(cx);
 742        let active_item_id = pane.items[pane.active_item_index].id();
 743
 744        let task = Self::close_items(workspace, pane_handle, cx, move |item_id| {
 745            item_id == active_item_id
 746        });
 747
 748        Some(cx.foreground().spawn(async move {
 749            task.await?;
 750            Ok(())
 751        }))
 752    }
 753
 754    pub fn close_inactive_items(
 755        workspace: &mut Workspace,
 756        _: &CloseInactiveItems,
 757        cx: &mut ViewContext<Workspace>,
 758    ) -> Option<Task<Result<()>>> {
 759        let pane_handle = workspace.active_pane().clone();
 760        let pane = pane_handle.read(cx);
 761        let active_item_id = pane.items[pane.active_item_index].id();
 762
 763        let task = Self::close_items(workspace, pane_handle, cx, move |item_id| {
 764            item_id != active_item_id
 765        });
 766
 767        Some(cx.foreground().spawn(async move {
 768            task.await?;
 769            Ok(())
 770        }))
 771    }
 772
 773    pub fn close_clean_items(
 774        workspace: &mut Workspace,
 775        _: &CloseCleanItems,
 776        cx: &mut ViewContext<Workspace>,
 777    ) -> Option<Task<Result<()>>> {
 778        let pane_handle = workspace.active_pane().clone();
 779        let pane = pane_handle.read(cx);
 780
 781        let item_ids: Vec<_> = pane
 782            .items()
 783            .filter(|item| !item.is_dirty(cx))
 784            .map(|item| item.id())
 785            .collect();
 786
 787        let task = Self::close_items(workspace, pane_handle, cx, move |item_id| {
 788            item_ids.contains(&item_id)
 789        });
 790
 791        Some(cx.foreground().spawn(async move {
 792            task.await?;
 793            Ok(())
 794        }))
 795    }
 796
 797    pub fn close_items_to_the_left(
 798        workspace: &mut Workspace,
 799        _: &CloseItemsToTheLeft,
 800        cx: &mut ViewContext<Workspace>,
 801    ) -> Option<Task<Result<()>>> {
 802        let pane_handle = workspace.active_pane().clone();
 803        let pane = pane_handle.read(cx);
 804        let active_item_id = pane.items[pane.active_item_index].id();
 805
 806        let item_ids: Vec<_> = pane
 807            .items()
 808            .take_while(|item| item.id() != active_item_id)
 809            .map(|item| item.id())
 810            .collect();
 811
 812        let task = Self::close_items(workspace, pane_handle, cx, move |item_id| {
 813            item_ids.contains(&item_id)
 814        });
 815
 816        Some(cx.foreground().spawn(async move {
 817            task.await?;
 818            Ok(())
 819        }))
 820    }
 821
 822    pub fn close_items_to_the_right(
 823        workspace: &mut Workspace,
 824        _: &CloseItemsToTheRight,
 825        cx: &mut ViewContext<Workspace>,
 826    ) -> Option<Task<Result<()>>> {
 827        let pane_handle = workspace.active_pane().clone();
 828        let pane = pane_handle.read(cx);
 829        let active_item_id = pane.items[pane.active_item_index].id();
 830
 831        let item_ids: Vec<_> = pane
 832            .items()
 833            .rev()
 834            .take_while(|item| item.id() != active_item_id)
 835            .map(|item| item.id())
 836            .collect();
 837
 838        let task = Self::close_items(workspace, pane_handle, cx, move |item_id| {
 839            item_ids.contains(&item_id)
 840        });
 841
 842        Some(cx.foreground().spawn(async move {
 843            task.await?;
 844            Ok(())
 845        }))
 846    }
 847
 848    pub fn close_all_items(
 849        workspace: &mut Workspace,
 850        _: &CloseAllItems,
 851        cx: &mut ViewContext<Workspace>,
 852    ) -> Option<Task<Result<()>>> {
 853        let pane_handle = workspace.active_pane().clone();
 854
 855        let task = Self::close_items(workspace, pane_handle, cx, move |_| true);
 856
 857        Some(cx.foreground().spawn(async move {
 858            task.await?;
 859            Ok(())
 860        }))
 861    }
 862
 863    pub fn close_item(
 864        workspace: &mut Workspace,
 865        pane: ViewHandle<Pane>,
 866        item_id_to_close: usize,
 867        cx: &mut ViewContext<Workspace>,
 868    ) -> Task<Result<()>> {
 869        Self::close_items(workspace, pane, cx, move |view_id| {
 870            view_id == item_id_to_close
 871        })
 872    }
 873
 874    pub fn close_items(
 875        workspace: &mut Workspace,
 876        pane: ViewHandle<Pane>,
 877        cx: &mut ViewContext<Workspace>,
 878        should_close: impl 'static + Fn(usize) -> bool,
 879    ) -> Task<Result<()>> {
 880        let project = workspace.project().clone();
 881
 882        // Find the items to close.
 883        let mut items_to_close = Vec::new();
 884        for item in &pane.read(cx).items {
 885            if should_close(item.id()) {
 886                items_to_close.push(item.boxed_clone());
 887            }
 888        }
 889
 890        // If a buffer is open both in a singleton editor and in a multibuffer, make sure
 891        // to focus the singleton buffer when prompting to save that buffer, as opposed
 892        // to focusing the multibuffer, because this gives the user a more clear idea
 893        // of what content they would be saving.
 894        items_to_close.sort_by_key(|item| !item.is_singleton(cx));
 895
 896        cx.spawn(|workspace, mut cx| async move {
 897            let mut saved_project_items_ids = HashSet::default();
 898            for item in items_to_close.clone() {
 899                // Find the item's current index and its set of project item models. Avoid
 900                // storing these in advance, in case they have changed since this task
 901                // was started.
 902                let (item_ix, mut project_item_ids) = pane.read_with(&cx, |pane, cx| {
 903                    (pane.index_for_item(&*item), item.project_item_model_ids(cx))
 904                });
 905                let item_ix = if let Some(ix) = item_ix {
 906                    ix
 907                } else {
 908                    continue;
 909                };
 910
 911                // Check if this view has any project items that are not open anywhere else
 912                // in the workspace, AND that the user has not already been prompted to save.
 913                // If there are any such project entries, prompt the user to save this item.
 914                workspace.read_with(&cx, |workspace, cx| {
 915                    for item in workspace.items(cx) {
 916                        if !items_to_close
 917                            .iter()
 918                            .any(|item_to_close| item_to_close.id() == item.id())
 919                        {
 920                            let other_project_item_ids = item.project_item_model_ids(cx);
 921                            project_item_ids.retain(|id| !other_project_item_ids.contains(id));
 922                        }
 923                    }
 924                });
 925                let should_save = project_item_ids
 926                    .iter()
 927                    .any(|id| saved_project_items_ids.insert(*id));
 928
 929                if should_save
 930                    && !Self::save_item(project.clone(), &pane, item_ix, &*item, true, &mut cx)
 931                        .await?
 932                {
 933                    break;
 934                }
 935
 936                // Remove the item from the pane.
 937                pane.update(&mut cx, |pane, cx| {
 938                    if let Some(item_ix) = pane.items.iter().position(|i| i.id() == item.id()) {
 939                        pane.remove_item(item_ix, false, cx);
 940                    }
 941                });
 942            }
 943
 944            pane.update(&mut cx, |_, cx| cx.notify());
 945            Ok(())
 946        })
 947    }
 948
 949    fn remove_item(&mut self, item_index: usize, activate_pane: bool, cx: &mut ViewContext<Self>) {
 950        self.activation_history
 951            .retain(|&history_entry| history_entry != self.items[item_index].id());
 952
 953        if item_index == self.active_item_index {
 954            let index_to_activate = self
 955                .activation_history
 956                .pop()
 957                .and_then(|last_activated_item| {
 958                    self.items.iter().enumerate().find_map(|(index, item)| {
 959                        (item.id() == last_activated_item).then_some(index)
 960                    })
 961                })
 962                // We didn't have a valid activation history entry, so fallback
 963                // to activating the item to the left
 964                .unwrap_or_else(|| item_index.min(self.items.len()).saturating_sub(1));
 965
 966            self.activate_item(index_to_activate, activate_pane, activate_pane, cx);
 967        }
 968
 969        let item = self.items.remove(item_index);
 970
 971        cx.emit(Event::RemoveItem { item_id: item.id() });
 972        if self.items.is_empty() {
 973            item.deactivated(cx);
 974            self.update_toolbar(cx);
 975            cx.emit(Event::Remove);
 976        }
 977
 978        if item_index < self.active_item_index {
 979            self.active_item_index -= 1;
 980        }
 981
 982        self.nav_history
 983            .borrow_mut()
 984            .set_mode(NavigationMode::ClosingItem);
 985        item.deactivated(cx);
 986        self.nav_history
 987            .borrow_mut()
 988            .set_mode(NavigationMode::Normal);
 989
 990        if let Some(path) = item.project_path(cx) {
 991            self.nav_history
 992                .borrow_mut()
 993                .paths_by_item
 994                .insert(item.id(), path);
 995        } else {
 996            self.nav_history
 997                .borrow_mut()
 998                .paths_by_item
 999                .remove(&item.id());
1000        }
1001
1002        cx.notify();
1003    }
1004
1005    pub async fn save_item(
1006        project: ModelHandle<Project>,
1007        pane: &ViewHandle<Pane>,
1008        item_ix: usize,
1009        item: &dyn ItemHandle,
1010        should_prompt_for_save: bool,
1011        cx: &mut AsyncAppContext,
1012    ) -> Result<bool> {
1013        const CONFLICT_MESSAGE: &str =
1014            "This file has changed on disk since you started editing it. Do you want to overwrite it?";
1015        const DIRTY_MESSAGE: &str = "This file contains unsaved edits. Do you want to save it?";
1016
1017        let (has_conflict, is_dirty, can_save, is_singleton) = cx.read(|cx| {
1018            (
1019                item.has_conflict(cx),
1020                item.is_dirty(cx),
1021                item.can_save(cx),
1022                item.is_singleton(cx),
1023            )
1024        });
1025
1026        if has_conflict && can_save {
1027            let mut answer = pane.update(cx, |pane, cx| {
1028                pane.activate_item(item_ix, true, true, cx);
1029                cx.prompt(
1030                    PromptLevel::Warning,
1031                    CONFLICT_MESSAGE,
1032                    &["Overwrite", "Discard", "Cancel"],
1033                )
1034            });
1035            match answer.next().await {
1036                Some(0) => cx.update(|cx| item.save(project, cx)).await?,
1037                Some(1) => cx.update(|cx| item.reload(project, cx)).await?,
1038                _ => return Ok(false),
1039            }
1040        } else if is_dirty && (can_save || is_singleton) {
1041            let will_autosave = cx.read(|cx| {
1042                matches!(
1043                    cx.global::<Settings>().autosave,
1044                    Autosave::OnFocusChange | Autosave::OnWindowChange
1045                ) && Self::can_autosave_item(&*item, cx)
1046            });
1047            let should_save = if should_prompt_for_save && !will_autosave {
1048                let mut answer = pane.update(cx, |pane, cx| {
1049                    pane.activate_item(item_ix, true, true, cx);
1050                    cx.prompt(
1051                        PromptLevel::Warning,
1052                        DIRTY_MESSAGE,
1053                        &["Save", "Don't Save", "Cancel"],
1054                    )
1055                });
1056                match answer.next().await {
1057                    Some(0) => true,
1058                    Some(1) => false,
1059                    _ => return Ok(false),
1060                }
1061            } else {
1062                true
1063            };
1064
1065            if should_save {
1066                if can_save {
1067                    cx.update(|cx| item.save(project, cx)).await?;
1068                } else if is_singleton {
1069                    let start_abs_path = project
1070                        .read_with(cx, |project, cx| {
1071                            let worktree = project.visible_worktrees(cx).next()?;
1072                            Some(worktree.read(cx).as_local()?.abs_path().to_path_buf())
1073                        })
1074                        .unwrap_or_else(|| Path::new("").into());
1075
1076                    let mut abs_path = cx.update(|cx| cx.prompt_for_new_path(&start_abs_path));
1077                    if let Some(abs_path) = abs_path.next().await.flatten() {
1078                        cx.update(|cx| item.save_as(project, abs_path, cx)).await?;
1079                    } else {
1080                        return Ok(false);
1081                    }
1082                }
1083            }
1084        }
1085        Ok(true)
1086    }
1087
1088    fn can_autosave_item(item: &dyn ItemHandle, cx: &AppContext) -> bool {
1089        let is_deleted = item.project_entry_ids(cx).is_empty();
1090        item.is_dirty(cx) && !item.has_conflict(cx) && item.can_save(cx) && !is_deleted
1091    }
1092
1093    pub fn autosave_item(
1094        item: &dyn ItemHandle,
1095        project: ModelHandle<Project>,
1096        cx: &mut AppContext,
1097    ) -> Task<Result<()>> {
1098        if Self::can_autosave_item(item, cx) {
1099            item.save(project, cx)
1100        } else {
1101            Task::ready(Ok(()))
1102        }
1103    }
1104
1105    pub fn focus_active_item(&mut self, cx: &mut ViewContext<Self>) {
1106        if let Some(active_item) = self.active_item() {
1107            cx.focus(active_item.as_any());
1108        }
1109    }
1110
1111    pub fn move_item(
1112        workspace: &mut Workspace,
1113        from: ViewHandle<Pane>,
1114        to: ViewHandle<Pane>,
1115        item_id_to_move: usize,
1116        destination_index: usize,
1117        cx: &mut ViewContext<Workspace>,
1118    ) {
1119        let item_to_move = from
1120            .read(cx)
1121            .items()
1122            .enumerate()
1123            .find(|(_, item_handle)| item_handle.id() == item_id_to_move);
1124
1125        if item_to_move.is_none() {
1126            log::warn!("Tried to move item handle which was not in `from` pane. Maybe tab was closed during drop");
1127            return;
1128        }
1129        let (item_ix, item_handle) = item_to_move.unwrap();
1130        let item_handle = item_handle.clone();
1131
1132        if from != to {
1133            // Close item from previous pane
1134            from.update(cx, |from, cx| {
1135                from.remove_item(item_ix, false, cx);
1136            });
1137        }
1138
1139        // This automatically removes duplicate items in the pane
1140        Pane::add_item(
1141            workspace,
1142            &to,
1143            item_handle,
1144            true,
1145            true,
1146            Some(destination_index),
1147            cx,
1148        );
1149
1150        cx.focus(&to);
1151    }
1152
1153    pub fn split(&mut self, direction: SplitDirection, cx: &mut ViewContext<Self>) {
1154        cx.emit(Event::Split(direction));
1155    }
1156
1157    fn deploy_split_menu(&mut self, _: &DeploySplitMenu, cx: &mut ViewContext<Self>) {
1158        self.tab_bar_context_menu.handle.update(cx, |menu, cx| {
1159            menu.show(
1160                Default::default(),
1161                AnchorCorner::TopRight,
1162                vec![
1163                    ContextMenuItem::item("Split Right", SplitRight),
1164                    ContextMenuItem::item("Split Left", SplitLeft),
1165                    ContextMenuItem::item("Split Up", SplitUp),
1166                    ContextMenuItem::item("Split Down", SplitDown),
1167                ],
1168                cx,
1169            );
1170        });
1171
1172        self.tab_bar_context_menu.kind = TabBarContextMenuKind::Split;
1173    }
1174
1175    fn deploy_dock_menu(&mut self, _: &DeployDockMenu, cx: &mut ViewContext<Self>) {
1176        self.tab_bar_context_menu.handle.update(cx, |menu, cx| {
1177            menu.show(
1178                Default::default(),
1179                AnchorCorner::TopRight,
1180                vec![
1181                    ContextMenuItem::item("Anchor Dock Right", AnchorDockRight),
1182                    ContextMenuItem::item("Anchor Dock Bottom", AnchorDockBottom),
1183                    ContextMenuItem::item("Expand Dock", ExpandDock),
1184                ],
1185                cx,
1186            );
1187        });
1188
1189        self.tab_bar_context_menu.kind = TabBarContextMenuKind::Dock;
1190    }
1191
1192    fn deploy_new_menu(&mut self, _: &DeployNewMenu, cx: &mut ViewContext<Self>) {
1193        self.tab_bar_context_menu.handle.update(cx, |menu, cx| {
1194            menu.show(
1195                Default::default(),
1196                AnchorCorner::TopRight,
1197                vec![
1198                    ContextMenuItem::item("New File", NewFile),
1199                    ContextMenuItem::item("New Terminal", NewTerminal),
1200                    ContextMenuItem::item("New Search", NewSearch),
1201                ],
1202                cx,
1203            );
1204        });
1205
1206        self.tab_bar_context_menu.kind = TabBarContextMenuKind::New;
1207    }
1208
1209    pub fn toolbar(&self) -> &ViewHandle<Toolbar> {
1210        &self.toolbar
1211    }
1212
1213    fn update_toolbar(&mut self, cx: &mut ViewContext<Self>) {
1214        let active_item = self
1215            .items
1216            .get(self.active_item_index)
1217            .map(|item| item.as_ref());
1218        self.toolbar.update(cx, |toolbar, cx| {
1219            toolbar.set_active_pane_item(active_item, cx);
1220        });
1221    }
1222
1223    fn render_tabs(&mut self, cx: &mut ViewContext<Self>) -> impl Drawable<Self> {
1224        let theme = cx.global::<Settings>().theme.clone();
1225
1226        let pane = cx.handle().downgrade();
1227        let autoscroll = if mem::take(&mut self.autoscroll) {
1228            Some(self.active_item_index)
1229        } else {
1230            None
1231        };
1232
1233        let pane_active = self.is_active;
1234
1235        enum Tabs {}
1236        let mut row = Flex::row().scrollable::<Tabs>(1, autoscroll, cx);
1237        for (ix, (item, detail)) in self
1238            .items
1239            .iter()
1240            .cloned()
1241            .zip(self.tab_details(cx))
1242            .enumerate()
1243        {
1244            let detail = if detail == 0 { None } else { Some(detail) };
1245            let tab_active = ix == self.active_item_index;
1246
1247            row.add_child({
1248                enum TabDragReceiver {}
1249                let mut receiver =
1250                    dragged_item_receiver::<TabDragReceiver, _>(ix, ix, true, None, cx, {
1251                        let item = item.clone();
1252                        let pane = pane.clone();
1253                        let detail = detail.clone();
1254
1255                        let theme = cx.global::<Settings>().theme.clone();
1256
1257                        move |mouse_state, cx| {
1258                            let tab_style =
1259                                theme.workspace.tab_bar.tab_style(pane_active, tab_active);
1260                            let hovered = mouse_state.hovered();
1261
1262                            enum Tab {}
1263                            MouseEventHandler::<Tab, Pane>::new(ix, cx, |_, cx| {
1264                                Self::render_tab::<Pane>(
1265                                    &item,
1266                                    pane.clone(),
1267                                    ix == 0,
1268                                    detail,
1269                                    hovered,
1270                                    tab_style,
1271                                    cx,
1272                                )
1273                            })
1274                            .on_down(MouseButton::Left, move |_, _, cx| {
1275                                cx.dispatch_action(ActivateItem(ix));
1276                            })
1277                            .on_click(MouseButton::Middle, {
1278                                let item = item.clone();
1279                                move |_, _, cx: &mut EventContext<Self>| {
1280                                    cx.dispatch_action(CloseItem {
1281                                        item_id: item.id(),
1282                                        pane: pane.clone(),
1283                                    })
1284                                }
1285                            })
1286                            .boxed()
1287                        }
1288                    });
1289
1290                if !pane_active || !tab_active {
1291                    receiver = receiver.with_cursor_style(CursorStyle::PointingHand);
1292                }
1293
1294                receiver
1295                    .as_draggable(
1296                        DraggedItem {
1297                            item,
1298                            pane: pane.clone(),
1299                        },
1300                        {
1301                            let theme = cx.global::<Settings>().theme.clone();
1302
1303                            let detail = detail.clone();
1304                            move |dragged_item: &DraggedItem, cx: &mut ViewContext<Pane>| {
1305                                let tab_style = &theme.workspace.tab_bar.dragged_tab;
1306                                Self::render_tab::<Pane>(
1307                                    &dragged_item.item,
1308                                    dragged_item.pane.clone(),
1309                                    false,
1310                                    detail,
1311                                    false,
1312                                    &tab_style,
1313                                    cx,
1314                                )
1315                            }
1316                        },
1317                    )
1318                    .boxed()
1319            })
1320        }
1321
1322        // Use the inactive tab style along with the current pane's active status to decide how to render
1323        // the filler
1324        let filler_index = self.items.len();
1325        let filler_style = theme.workspace.tab_bar.tab_style(pane_active, false);
1326        enum Filler {}
1327        row.add_child(
1328            dragged_item_receiver::<Filler, _>(0, filler_index, true, None, cx, |_, _| {
1329                Empty::new()
1330                    .contained()
1331                    .with_style(filler_style.container)
1332                    .with_border(filler_style.container.border)
1333                    .boxed()
1334            })
1335            .flex(1., true)
1336            .named("filler"),
1337        );
1338
1339        row
1340    }
1341
1342    fn tab_details(&self, cx: &AppContext) -> Vec<usize> {
1343        let mut tab_details = (0..self.items.len()).map(|_| 0).collect::<Vec<_>>();
1344
1345        let mut tab_descriptions = HashMap::default();
1346        let mut done = false;
1347        while !done {
1348            done = true;
1349
1350            // Store item indices by their tab description.
1351            for (ix, (item, detail)) in self.items.iter().zip(&tab_details).enumerate() {
1352                if let Some(description) = item.tab_description(*detail, cx) {
1353                    if *detail == 0
1354                        || Some(&description) != item.tab_description(detail - 1, cx).as_ref()
1355                    {
1356                        tab_descriptions
1357                            .entry(description)
1358                            .or_insert(Vec::new())
1359                            .push(ix);
1360                    }
1361                }
1362            }
1363
1364            // If two or more items have the same tab description, increase their level
1365            // of detail and try again.
1366            for (_, item_ixs) in tab_descriptions.drain() {
1367                if item_ixs.len() > 1 {
1368                    done = false;
1369                    for ix in item_ixs {
1370                        tab_details[ix] += 1;
1371                    }
1372                }
1373            }
1374        }
1375
1376        tab_details
1377    }
1378
1379    fn render_tab<V: View>(
1380        item: &Box<dyn ItemHandle>,
1381        pane: WeakViewHandle<Pane>,
1382        first: bool,
1383        detail: Option<usize>,
1384        hovered: bool,
1385        tab_style: &theme::Tab,
1386        cx: &mut ViewContext<Self>,
1387    ) -> Element<Self> {
1388        let title = item.tab_content(detail, &tab_style, cx);
1389        let mut container = tab_style.container.clone();
1390        if first {
1391            container.border.left = false;
1392        }
1393
1394        Flex::row()
1395            .with_child(
1396                Align::new({
1397                    let diameter = 7.0;
1398                    let icon_color = if item.has_conflict(cx) {
1399                        Some(tab_style.icon_conflict)
1400                    } else if item.is_dirty(cx) {
1401                        Some(tab_style.icon_dirty)
1402                    } else {
1403                        None
1404                    };
1405
1406                    ConstrainedBox::new(
1407                        Canvas::new(move |scene, bounds, _, _, _| {
1408                            if let Some(color) = icon_color {
1409                                let square = RectF::new(bounds.origin(), vec2f(diameter, diameter));
1410                                scene.push_quad(Quad {
1411                                    bounds: square,
1412                                    background: Some(color),
1413                                    border: Default::default(),
1414                                    corner_radius: diameter / 2.,
1415                                });
1416                            }
1417                        })
1418                        .boxed(),
1419                    )
1420                    .with_width(diameter)
1421                    .with_height(diameter)
1422                    .boxed()
1423                })
1424                .boxed(),
1425            )
1426            .with_child(
1427                Container::new(Align::new(title).boxed())
1428                    .with_style(ContainerStyle {
1429                        margin: Margin {
1430                            left: tab_style.spacing,
1431                            right: tab_style.spacing,
1432                            ..Default::default()
1433                        },
1434                        ..Default::default()
1435                    })
1436                    .boxed(),
1437            )
1438            .with_child(
1439                Align::new(
1440                    ConstrainedBox::new(if hovered {
1441                        let item_id = item.id();
1442                        enum TabCloseButton {}
1443                        let icon = Svg::new("icons/x_mark_8.svg");
1444                        MouseEventHandler::<TabCloseButton, _>::new(
1445                            item_id,
1446                            cx,
1447                            |mouse_state, _| {
1448                                if mouse_state.hovered() {
1449                                    icon.with_color(tab_style.icon_close_active).boxed()
1450                                } else {
1451                                    icon.with_color(tab_style.icon_close).boxed()
1452                                }
1453                            },
1454                        )
1455                        .with_padding(Padding::uniform(4.))
1456                        .with_cursor_style(CursorStyle::PointingHand)
1457                        .on_click(MouseButton::Left, {
1458                            let pane = pane.clone();
1459                            move |_, _, cx| {
1460                                cx.dispatch_action(CloseItem {
1461                                    item_id,
1462                                    pane: pane.clone(),
1463                                })
1464                            }
1465                        })
1466                        .named("close-tab-icon")
1467                    } else {
1468                        Empty::new().boxed()
1469                    })
1470                    .with_width(tab_style.close_icon_width)
1471                    .boxed(),
1472                )
1473                .boxed(),
1474            )
1475            .contained()
1476            .with_style(container)
1477            .constrained()
1478            .with_height(tab_style.height)
1479            .boxed()
1480    }
1481
1482    fn render_tab_bar_buttons(
1483        &mut self,
1484        theme: &Theme,
1485        cx: &mut ViewContext<Self>,
1486    ) -> Element<Self> {
1487        Flex::row()
1488            // New menu
1489            .with_child(render_tab_bar_button(
1490                0,
1491                "icons/plus_12.svg",
1492                cx,
1493                DeployNewMenu,
1494                self.tab_bar_context_menu
1495                    .handle_if_kind(TabBarContextMenuKind::New),
1496            ))
1497            .with_child(
1498                self.docked
1499                    .map(|anchor| {
1500                        // Add the dock menu button if this pane is a dock
1501                        let dock_icon = icon_for_dock_anchor(anchor);
1502
1503                        render_tab_bar_button(
1504                            1,
1505                            dock_icon,
1506                            cx,
1507                            DeployDockMenu,
1508                            self.tab_bar_context_menu
1509                                .handle_if_kind(TabBarContextMenuKind::Dock),
1510                        )
1511                    })
1512                    .unwrap_or_else(|| {
1513                        // Add the split menu if this pane is not a dock
1514                        render_tab_bar_button(
1515                            2,
1516                            "icons/split_12.svg",
1517                            cx,
1518                            DeploySplitMenu,
1519                            self.tab_bar_context_menu
1520                                .handle_if_kind(TabBarContextMenuKind::Split),
1521                        )
1522                    }),
1523            )
1524            // Add the close dock button if this pane is a dock
1525            .with_children(
1526                self.docked
1527                    .map(|_| render_tab_bar_button(3, "icons/x_mark_8.svg", cx, HideDock, None)),
1528            )
1529            .contained()
1530            .with_style(theme.workspace.tab_bar.pane_button_container)
1531            .flex(1., false)
1532            .boxed()
1533    }
1534
1535    fn render_blank_pane(
1536        &mut self,
1537        theme: &Theme,
1538        _cx: &mut ViewContext<Self>,
1539    ) -> Element<Self> {
1540        let background = theme.workspace.background;
1541        Empty::new()
1542            .contained()
1543            .with_background_color(background)
1544            .boxed()
1545    }
1546}
1547
1548impl Entity for Pane {
1549    type Event = Event;
1550}
1551
1552impl View for Pane {
1553    fn ui_name() -> &'static str {
1554        "Pane"
1555    }
1556
1557    fn render(&mut self, cx: &mut ViewContext<Self>) -> Element<Self> {
1558        let this = cx.handle().downgrade();
1559
1560        enum MouseNavigationHandler {}
1561
1562        Stack::new()
1563            .with_child(
1564                MouseEventHandler::<MouseNavigationHandler, _>::new(0, cx, |_, cx| {
1565                    let active_item_index = self.active_item_index;
1566
1567                    if let Some(active_item) = self.active_item() {
1568                        Flex::column()
1569                            .with_child({
1570                                let theme = cx.global::<Settings>().theme.clone();
1571
1572                                let mut stack = Stack::new();
1573
1574                                enum TabBarEventHandler {}
1575                                stack.add_child(
1576                                    MouseEventHandler::<TabBarEventHandler, _>::new(
1577                                        0,
1578                                        cx,
1579                                        |_, _| {
1580                                            Empty::new()
1581                                                .contained()
1582                                                .with_style(theme.workspace.tab_bar.container)
1583                                                .boxed()
1584                                        },
1585                                    )
1586                                    .on_down(MouseButton::Left, move |_, _, cx| {
1587                                        cx.dispatch_action(ActivateItem(active_item_index));
1588                                    })
1589                                    .boxed(),
1590                                );
1591
1592                                let mut tab_row = Flex::row()
1593                                    .with_child(self.render_tabs(cx).flex(1., true).named("tabs"));
1594
1595                                if self.is_active {
1596                                    tab_row.add_child(self.render_tab_bar_buttons(&theme, cx))
1597                                }
1598
1599                                stack.add_child(tab_row.boxed());
1600                                stack
1601                                    .constrained()
1602                                    .with_height(theme.workspace.tab_bar.height)
1603                                    .flex(1., false)
1604                                    .named("tab bar")
1605                            })
1606                            .with_child({
1607                                enum PaneContentTabDropTarget {}
1608                                dragged_item_receiver::<PaneContentTabDropTarget, _>(
1609                                    0,
1610                                    self.active_item_index + 1,
1611                                    false,
1612                                    if self.docked.is_some() {
1613                                        None
1614                                    } else {
1615                                        Some(100.)
1616                                    },
1617                                    cx,
1618                                    {
1619                                        let toolbar = self.toolbar.clone();
1620                                        let toolbar_hidden = toolbar.read(cx).hidden();
1621                                        move |_, cx| {
1622                                            Flex::column()
1623                                                .with_children((!toolbar_hidden).then(|| {
1624                                                    ChildView::new(&toolbar, cx).expanded().boxed()
1625                                                }))
1626                                                .with_child(
1627                                                    ChildView::new(active_item.as_any(), cx)
1628                                                        .flex(1., true)
1629                                                        .boxed(),
1630                                                )
1631                                                .boxed()
1632                                        }
1633                                    },
1634                                )
1635                                .flex(1., true)
1636                                .boxed()
1637                            })
1638                            .boxed()
1639                    } else {
1640                        enum EmptyPane {}
1641                        let theme = cx.global::<Settings>().theme.clone();
1642
1643                        dragged_item_receiver::<EmptyPane, _>(0, 0, false, None, cx, |_, cx| {
1644                            self.render_blank_pane(&theme, cx)
1645                        })
1646                        .on_down(MouseButton::Left, |_, _, cx| {
1647                            cx.focus_parent_view();
1648                        })
1649                        .boxed()
1650                    }
1651                })
1652                .on_down(MouseButton::Navigate(NavigationDirection::Back), {
1653                    let this = this.clone();
1654                    move |_, _, cx| {
1655                        cx.dispatch_action(GoBack {
1656                            pane: Some(this.clone()),
1657                        });
1658                    }
1659                })
1660                .on_down(MouseButton::Navigate(NavigationDirection::Forward), {
1661                    let this = this.clone();
1662                    move |_, _, cx| {
1663                        cx.dispatch_action(GoForward {
1664                            pane: Some(this.clone()),
1665                        })
1666                    }
1667                })
1668                .boxed(),
1669            )
1670            .named("pane")
1671    }
1672
1673    fn focus_in(&mut self, focused: AnyViewHandle, cx: &mut ViewContext<Self>) {
1674        self.toolbar.update(cx, |toolbar, cx| {
1675            toolbar.pane_focus_update(true, cx);
1676        });
1677
1678        if let Some(active_item) = self.active_item() {
1679            if cx.is_self_focused() {
1680                // Pane was focused directly. We need to either focus a view inside the active item,
1681                // or focus the active item itself
1682                if let Some(weak_last_focused_view) =
1683                    self.last_focused_view_by_item.get(&active_item.id())
1684                {
1685                    if let Some(last_focused_view) = weak_last_focused_view.upgrade(cx) {
1686                        cx.focus(&last_focused_view);
1687                        return;
1688                    } else {
1689                        self.last_focused_view_by_item.remove(&active_item.id());
1690                    }
1691                }
1692
1693                cx.focus(active_item.as_any());
1694            } else if focused != self.tab_bar_context_menu.handle {
1695                self.last_focused_view_by_item
1696                    .insert(active_item.id(), focused.downgrade());
1697            }
1698        }
1699    }
1700
1701    fn focus_out(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
1702        self.toolbar.update(cx, |toolbar, cx| {
1703            toolbar.pane_focus_update(false, cx);
1704        });
1705    }
1706
1707    fn keymap_context(&self, _: &AppContext) -> KeymapContext {
1708        let mut keymap = Self::default_keymap_context();
1709        if self.docked.is_some() {
1710            keymap.add_identifier("docked");
1711        }
1712        keymap
1713    }
1714}
1715
1716fn render_tab_bar_button<A: Action + Clone>(
1717    index: usize,
1718    icon: &'static str,
1719    cx: &mut ViewContext<Pane>,
1720    action: A,
1721    context_menu: Option<ViewHandle<ContextMenu>>,
1722) -> Element<Pane> {
1723    enum TabBarButton {}
1724
1725    Stack::new()
1726        .with_child(
1727            MouseEventHandler::<TabBarButton, _>::new(index, cx, |mouse_state, cx| {
1728                let theme = &cx.global::<Settings>().theme.workspace.tab_bar;
1729                let style = theme.pane_button.style_for(mouse_state, false);
1730                Svg::new(icon)
1731                    .with_color(style.color)
1732                    .constrained()
1733                    .with_width(style.icon_width)
1734                    .aligned()
1735                    .constrained()
1736                    .with_width(style.button_width)
1737                    .with_height(style.button_width)
1738                    .boxed()
1739            })
1740            .with_cursor_style(CursorStyle::PointingHand)
1741            .on_click(MouseButton::Left, move |_, _, cx| {
1742                cx.dispatch_action(action.clone());
1743            })
1744            .boxed(),
1745        )
1746        .with_children(
1747            context_menu.map(|menu| ChildView::new(&menu, cx).aligned().bottom().right().boxed()),
1748        )
1749        .flex(1., false)
1750        .boxed()
1751}
1752
1753impl ItemNavHistory {
1754    pub fn push<D: 'static + Any>(&self, data: Option<D>, cx: &mut AppContext) {
1755        self.history.borrow_mut().push(data, self.item.clone(), cx);
1756    }
1757
1758    pub fn pop_backward(&self, cx: &mut AppContext) -> Option<NavigationEntry> {
1759        self.history.borrow_mut().pop(NavigationMode::GoingBack, cx)
1760    }
1761
1762    pub fn pop_forward(&self, cx: &mut AppContext) -> Option<NavigationEntry> {
1763        self.history
1764            .borrow_mut()
1765            .pop(NavigationMode::GoingForward, cx)
1766    }
1767}
1768
1769impl NavHistory {
1770    fn set_mode(&mut self, mode: NavigationMode) {
1771        self.mode = mode;
1772    }
1773
1774    fn disable(&mut self) {
1775        self.mode = NavigationMode::Disabled;
1776    }
1777
1778    fn enable(&mut self) {
1779        self.mode = NavigationMode::Normal;
1780    }
1781
1782    fn pop(&mut self, mode: NavigationMode, cx: &mut AppContext) -> Option<NavigationEntry> {
1783        let entry = match mode {
1784            NavigationMode::Normal | NavigationMode::Disabled | NavigationMode::ClosingItem => {
1785                return None
1786            }
1787            NavigationMode::GoingBack => &mut self.backward_stack,
1788            NavigationMode::GoingForward => &mut self.forward_stack,
1789            NavigationMode::ReopeningClosedItem => &mut self.closed_stack,
1790        }
1791        .pop_back();
1792        if entry.is_some() {
1793            self.did_update(cx);
1794        }
1795        entry
1796    }
1797
1798    fn push<D: 'static + Any>(
1799        &mut self,
1800        data: Option<D>,
1801        item: Rc<dyn WeakItemHandle>,
1802        cx: &mut AppContext,
1803    ) {
1804        match self.mode {
1805            NavigationMode::Disabled => {}
1806            NavigationMode::Normal | NavigationMode::ReopeningClosedItem => {
1807                if self.backward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
1808                    self.backward_stack.pop_front();
1809                }
1810                self.backward_stack.push_back(NavigationEntry {
1811                    item,
1812                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
1813                });
1814                self.forward_stack.clear();
1815            }
1816            NavigationMode::GoingBack => {
1817                if self.forward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
1818                    self.forward_stack.pop_front();
1819                }
1820                self.forward_stack.push_back(NavigationEntry {
1821                    item,
1822                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
1823                });
1824            }
1825            NavigationMode::GoingForward => {
1826                if self.backward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
1827                    self.backward_stack.pop_front();
1828                }
1829                self.backward_stack.push_back(NavigationEntry {
1830                    item,
1831                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
1832                });
1833            }
1834            NavigationMode::ClosingItem => {
1835                if self.closed_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
1836                    self.closed_stack.pop_front();
1837                }
1838                self.closed_stack.push_back(NavigationEntry {
1839                    item,
1840                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
1841                });
1842            }
1843        }
1844        self.did_update(cx);
1845    }
1846
1847    fn did_update(&self, cx: &mut AppContext) {
1848        if let Some(pane) = self.pane.upgrade(cx) {
1849            cx.defer(move |cx| pane.update(cx, |pane, cx| pane.history_updated(cx)));
1850        }
1851    }
1852}
1853
1854pub struct PaneBackdrop<V: View> {
1855    child_view: usize,
1856    child: Element<V>,
1857}
1858
1859impl<V: View> PaneBackdrop<V> {
1860    pub fn new(pane_item_view: usize, child: Element<V>) -> Self {
1861        PaneBackdrop {
1862            child,
1863            child_view: pane_item_view,
1864        }
1865    }
1866}
1867
1868impl<V: View> Drawable<V> for PaneBackdrop<V> {
1869    type LayoutState = ();
1870
1871    type PaintState = ();
1872
1873    fn layout(
1874        &mut self,
1875        constraint: gpui::SizeConstraint,
1876        view: &mut V,
1877        cx: &mut ViewContext<V>,
1878    ) -> (Vector2F, Self::LayoutState) {
1879        let size = self.child.layout(constraint, view, cx);
1880        (size, ())
1881    }
1882
1883    fn paint(
1884        &mut self,
1885        scene: &mut gpui::SceneBuilder,
1886        bounds: RectF,
1887        visible_bounds: RectF,
1888        _: &mut Self::LayoutState,
1889        view: &mut V,
1890        cx: &mut ViewContext<V>,
1891    ) -> Self::PaintState {
1892        let background = cx.global::<Settings>().theme.editor.background;
1893
1894        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
1895
1896        scene.push_quad(gpui::Quad {
1897            bounds: RectF::new(bounds.origin(), bounds.size()),
1898            background: Some(background),
1899            ..Default::default()
1900        });
1901
1902        let child_view_id = self.child_view;
1903        scene.push_mouse_region(
1904            MouseRegion::new::<Self>(child_view_id, 0, visible_bounds).on_down(
1905                gpui::platform::MouseButton::Left,
1906                move |_, _: &mut V, cx| {
1907                    let window_id = cx.window_id();
1908                    cx.app_context().focus(window_id, Some(child_view_id))
1909                },
1910            ),
1911        );
1912
1913        scene.paint_layer(Some(bounds), |scene| {
1914            self.child
1915                .paint(scene, bounds.origin(), visible_bounds, view, cx)
1916        })
1917    }
1918
1919    fn rect_for_text_range(
1920        &self,
1921        range_utf16: std::ops::Range<usize>,
1922        _bounds: RectF,
1923        _visible_bounds: RectF,
1924        _layout: &Self::LayoutState,
1925        _paint: &Self::PaintState,
1926        view: &V,
1927        cx: &gpui::ViewContext<V>,
1928    ) -> Option<RectF> {
1929        self.child.rect_for_text_range(range_utf16, view, cx)
1930    }
1931
1932    fn debug(
1933        &self,
1934        _bounds: RectF,
1935        _layout: &Self::LayoutState,
1936        _paint: &Self::PaintState,
1937        view: &V,
1938        cx: &gpui::ViewContext<V>,
1939    ) -> serde_json::Value {
1940        gpui::json::json!({
1941            "type": "Pane Back Drop",
1942            "view": self.child_view,
1943            "child": self.child.debug(view, cx),
1944        })
1945    }
1946}
1947
1948#[cfg(test)]
1949mod tests {
1950    use std::sync::Arc;
1951
1952    use super::*;
1953    use crate::item::test::{TestItem, TestProjectItem};
1954    use gpui::{executor::Deterministic, TestAppContext};
1955    use project::FakeFs;
1956
1957    #[gpui::test]
1958    async fn test_add_item_with_new_item(cx: &mut TestAppContext) {
1959        cx.foreground().forbid_parking();
1960        Settings::test_async(cx);
1961        let fs = FakeFs::new(cx.background());
1962
1963        let project = Project::test(fs, None, cx).await;
1964        let (_, workspace) = cx.add_window(|cx| Workspace::test_new(project.clone(), cx));
1965        let pane = workspace.read_with(cx, |workspace, _| workspace.active_pane().clone());
1966
1967        // 1. Add with a destination index
1968        //   a. Add before the active item
1969        set_labeled_items(&workspace, &pane, ["A", "B*", "C"], cx);
1970        workspace.update(cx, |workspace, cx| {
1971            Pane::add_item(
1972                workspace,
1973                &pane,
1974                Box::new(cx.add_view(|_| TestItem::new().with_label("D"))),
1975                false,
1976                false,
1977                Some(0),
1978                cx,
1979            );
1980        });
1981        assert_item_labels(&pane, ["D*", "A", "B", "C"], cx);
1982
1983        //   b. Add after the active item
1984        set_labeled_items(&workspace, &pane, ["A", "B*", "C"], cx);
1985        workspace.update(cx, |workspace, cx| {
1986            Pane::add_item(
1987                workspace,
1988                &pane,
1989                Box::new(cx.add_view(|_| TestItem::new().with_label("D"))),
1990                false,
1991                false,
1992                Some(2),
1993                cx,
1994            );
1995        });
1996        assert_item_labels(&pane, ["A", "B", "D*", "C"], cx);
1997
1998        //   c. Add at the end of the item list (including off the length)
1999        set_labeled_items(&workspace, &pane, ["A", "B*", "C"], cx);
2000        workspace.update(cx, |workspace, cx| {
2001            Pane::add_item(
2002                workspace,
2003                &pane,
2004                Box::new(cx.add_view(|_| TestItem::new().with_label("D"))),
2005                false,
2006                false,
2007                Some(5),
2008                cx,
2009            );
2010        });
2011        assert_item_labels(&pane, ["A", "B", "C", "D*"], cx);
2012
2013        // 2. Add without a destination index
2014        //   a. Add with active item at the start of the item list
2015        set_labeled_items(&workspace, &pane, ["A*", "B", "C"], cx);
2016        workspace.update(cx, |workspace, cx| {
2017            Pane::add_item(
2018                workspace,
2019                &pane,
2020                Box::new(cx.add_view(|_| TestItem::new().with_label("D"))),
2021                false,
2022                false,
2023                None,
2024                cx,
2025            );
2026        });
2027        set_labeled_items(&workspace, &pane, ["A", "D*", "B", "C"], cx);
2028
2029        //   b. Add with active item at the end of the item list
2030        set_labeled_items(&workspace, &pane, ["A", "B", "C*"], cx);
2031        workspace.update(cx, |workspace, cx| {
2032            Pane::add_item(
2033                workspace,
2034                &pane,
2035                Box::new(cx.add_view(|_| TestItem::new().with_label("D"))),
2036                false,
2037                false,
2038                None,
2039                cx,
2040            );
2041        });
2042        assert_item_labels(&pane, ["A", "B", "C", "D*"], cx);
2043    }
2044
2045    #[gpui::test]
2046    async fn test_add_item_with_existing_item(cx: &mut TestAppContext) {
2047        cx.foreground().forbid_parking();
2048        Settings::test_async(cx);
2049        let fs = FakeFs::new(cx.background());
2050
2051        let project = Project::test(fs, None, cx).await;
2052        let (_, workspace) = cx.add_window(|cx| Workspace::test_new(project.clone(), cx));
2053        let pane = workspace.read_with(cx, |workspace, _| workspace.active_pane().clone());
2054
2055        // 1. Add with a destination index
2056        //   1a. Add before the active item
2057        let [_, _, _, d] = set_labeled_items(&workspace, &pane, ["A", "B*", "C", "D"], cx);
2058        workspace.update(cx, |workspace, cx| {
2059            Pane::add_item(workspace, &pane, d, false, false, Some(0), cx);
2060        });
2061        assert_item_labels(&pane, ["D*", "A", "B", "C"], cx);
2062
2063        //   1b. Add after the active item
2064        let [_, _, _, d] = set_labeled_items(&workspace, &pane, ["A", "B*", "C", "D"], cx);
2065        workspace.update(cx, |workspace, cx| {
2066            Pane::add_item(workspace, &pane, d, false, false, Some(2), cx);
2067        });
2068        assert_item_labels(&pane, ["A", "B", "D*", "C"], cx);
2069
2070        //   1c. Add at the end of the item list (including off the length)
2071        let [a, _, _, _] = set_labeled_items(&workspace, &pane, ["A", "B*", "C", "D"], cx);
2072        workspace.update(cx, |workspace, cx| {
2073            Pane::add_item(workspace, &pane, a, false, false, Some(5), cx);
2074        });
2075        assert_item_labels(&pane, ["B", "C", "D", "A*"], cx);
2076
2077        //   1d. Add same item to active index
2078        let [_, b, _] = set_labeled_items(&workspace, &pane, ["A", "B*", "C"], cx);
2079        workspace.update(cx, |workspace, cx| {
2080            Pane::add_item(workspace, &pane, b, false, false, Some(1), cx);
2081        });
2082        assert_item_labels(&pane, ["A", "B*", "C"], cx);
2083
2084        //   1e. Add item to index after same item in last position
2085        let [_, _, c] = set_labeled_items(&workspace, &pane, ["A", "B*", "C"], cx);
2086        workspace.update(cx, |workspace, cx| {
2087            Pane::add_item(workspace, &pane, c, false, false, Some(2), cx);
2088        });
2089        assert_item_labels(&pane, ["A", "B", "C*"], cx);
2090
2091        // 2. Add without a destination index
2092        //   2a. Add with active item at the start of the item list
2093        let [_, _, _, d] = set_labeled_items(&workspace, &pane, ["A*", "B", "C", "D"], cx);
2094        workspace.update(cx, |workspace, cx| {
2095            Pane::add_item(workspace, &pane, d, false, false, None, cx);
2096        });
2097        assert_item_labels(&pane, ["A", "D*", "B", "C"], cx);
2098
2099        //   2b. Add with active item at the end of the item list
2100        let [a, _, _, _] = set_labeled_items(&workspace, &pane, ["A", "B", "C", "D*"], cx);
2101        workspace.update(cx, |workspace, cx| {
2102            Pane::add_item(workspace, &pane, a, false, false, None, cx);
2103        });
2104        assert_item_labels(&pane, ["B", "C", "D", "A*"], cx);
2105
2106        //   2c. Add active item to active item at end of list
2107        let [_, _, c] = set_labeled_items(&workspace, &pane, ["A", "B", "C*"], cx);
2108        workspace.update(cx, |workspace, cx| {
2109            Pane::add_item(workspace, &pane, c, false, false, None, cx);
2110        });
2111        assert_item_labels(&pane, ["A", "B", "C*"], cx);
2112
2113        //   2d. Add active item to active item at start of list
2114        let [a, _, _] = set_labeled_items(&workspace, &pane, ["A*", "B", "C"], cx);
2115        workspace.update(cx, |workspace, cx| {
2116            Pane::add_item(workspace, &pane, a, false, false, None, cx);
2117        });
2118        assert_item_labels(&pane, ["A*", "B", "C"], cx);
2119    }
2120
2121    #[gpui::test]
2122    async fn test_add_item_with_same_project_entries(cx: &mut TestAppContext) {
2123        cx.foreground().forbid_parking();
2124        Settings::test_async(cx);
2125        let fs = FakeFs::new(cx.background());
2126
2127        let project = Project::test(fs, None, cx).await;
2128        let (_, workspace) = cx.add_window(|cx| Workspace::test_new(project.clone(), cx));
2129        let pane = workspace.read_with(cx, |workspace, _| workspace.active_pane().clone());
2130
2131        // singleton view
2132        workspace.update(cx, |workspace, cx| {
2133            let item = TestItem::new()
2134                .with_singleton(true)
2135                .with_label("buffer 1")
2136                .with_project_items(&[TestProjectItem::new(1, "one.txt", cx)]);
2137
2138            Pane::add_item(
2139                workspace,
2140                &pane,
2141                Box::new(cx.add_view(|_| item)),
2142                false,
2143                false,
2144                None,
2145                cx,
2146            );
2147        });
2148        assert_item_labels(&pane, ["buffer 1*"], cx);
2149
2150        // new singleton view with the same project entry
2151        workspace.update(cx, |workspace, cx| {
2152            let item = TestItem::new()
2153                .with_singleton(true)
2154                .with_label("buffer 1")
2155                .with_project_items(&[TestProjectItem::new(1, "1.txt", cx)]);
2156
2157            Pane::add_item(
2158                workspace,
2159                &pane,
2160                Box::new(cx.add_view(|_| item)),
2161                false,
2162                false,
2163                None,
2164                cx,
2165            );
2166        });
2167        assert_item_labels(&pane, ["buffer 1*"], cx);
2168
2169        // new singleton view with different project entry
2170        workspace.update(cx, |workspace, cx| {
2171            let item = TestItem::new()
2172                .with_singleton(true)
2173                .with_label("buffer 2")
2174                .with_project_items(&[TestProjectItem::new(2, "2.txt", cx)]);
2175
2176            Pane::add_item(
2177                workspace,
2178                &pane,
2179                Box::new(cx.add_view(|_| item)),
2180                false,
2181                false,
2182                None,
2183                cx,
2184            );
2185        });
2186        assert_item_labels(&pane, ["buffer 1", "buffer 2*"], cx);
2187
2188        // new multibuffer view with the same project entry
2189        workspace.update(cx, |workspace, cx| {
2190            let item = TestItem::new()
2191                .with_singleton(false)
2192                .with_label("multibuffer 1")
2193                .with_project_items(&[TestProjectItem::new(1, "1.txt", cx)]);
2194
2195            Pane::add_item(
2196                workspace,
2197                &pane,
2198                Box::new(cx.add_view(|_| item)),
2199                false,
2200                false,
2201                None,
2202                cx,
2203            );
2204        });
2205        assert_item_labels(&pane, ["buffer 1", "buffer 2", "multibuffer 1*"], cx);
2206
2207        // another multibuffer view with the same project entry
2208        workspace.update(cx, |workspace, cx| {
2209            let item = TestItem::new()
2210                .with_singleton(false)
2211                .with_label("multibuffer 1b")
2212                .with_project_items(&[TestProjectItem::new(1, "1.txt", cx)]);
2213
2214            Pane::add_item(
2215                workspace,
2216                &pane,
2217                Box::new(cx.add_view(|_| item)),
2218                false,
2219                false,
2220                None,
2221                cx,
2222            );
2223        });
2224        assert_item_labels(
2225            &pane,
2226            ["buffer 1", "buffer 2", "multibuffer 1", "multibuffer 1b*"],
2227            cx,
2228        );
2229    }
2230
2231    #[gpui::test]
2232    async fn test_remove_item_ordering(deterministic: Arc<Deterministic>, cx: &mut TestAppContext) {
2233        Settings::test_async(cx);
2234        let fs = FakeFs::new(cx.background());
2235
2236        let project = Project::test(fs, None, cx).await;
2237        let (_, workspace) = cx.add_window(|cx| Workspace::test_new(project.clone(), cx));
2238        let pane = workspace.read_with(cx, |workspace, _| workspace.active_pane().clone());
2239
2240        add_labled_item(&workspace, &pane, "A", cx);
2241        add_labled_item(&workspace, &pane, "B", cx);
2242        add_labled_item(&workspace, &pane, "C", cx);
2243        add_labled_item(&workspace, &pane, "D", cx);
2244        assert_item_labels(&pane, ["A", "B", "C", "D*"], cx);
2245
2246        pane.update(cx, |pane, cx| pane.activate_item(1, false, false, cx));
2247        add_labled_item(&workspace, &pane, "1", cx);
2248        assert_item_labels(&pane, ["A", "B", "1*", "C", "D"], cx);
2249
2250        workspace.update(cx, |workspace, cx| {
2251            Pane::close_active_item(workspace, &CloseActiveItem, cx);
2252        });
2253        deterministic.run_until_parked();
2254        assert_item_labels(&pane, ["A", "B*", "C", "D"], cx);
2255
2256        pane.update(cx, |pane, cx| pane.activate_item(3, false, false, cx));
2257        assert_item_labels(&pane, ["A", "B", "C", "D*"], cx);
2258
2259        workspace.update(cx, |workspace, cx| {
2260            Pane::close_active_item(workspace, &CloseActiveItem, cx);
2261        });
2262        deterministic.run_until_parked();
2263        assert_item_labels(&pane, ["A", "B*", "C"], cx);
2264
2265        workspace.update(cx, |workspace, cx| {
2266            Pane::close_active_item(workspace, &CloseActiveItem, cx);
2267        });
2268        deterministic.run_until_parked();
2269        assert_item_labels(&pane, ["A", "C*"], cx);
2270
2271        workspace.update(cx, |workspace, cx| {
2272            Pane::close_active_item(workspace, &CloseActiveItem, cx);
2273        });
2274        deterministic.run_until_parked();
2275        assert_item_labels(&pane, ["A*"], cx);
2276    }
2277
2278    fn add_labled_item(
2279        workspace: &ViewHandle<Workspace>,
2280        pane: &ViewHandle<Pane>,
2281        label: &str,
2282        cx: &mut TestAppContext,
2283    ) -> Box<ViewHandle<TestItem>> {
2284        workspace.update(cx, |workspace, cx| {
2285            let labeled_item = Box::new(cx.add_view(|_| TestItem::new().with_label(label)));
2286
2287            Pane::add_item(
2288                workspace,
2289                pane,
2290                labeled_item.clone(),
2291                false,
2292                false,
2293                None,
2294                cx,
2295            );
2296
2297            labeled_item
2298        })
2299    }
2300
2301    fn set_labeled_items<const COUNT: usize>(
2302        workspace: &ViewHandle<Workspace>,
2303        pane: &ViewHandle<Pane>,
2304        labels: [&str; COUNT],
2305        cx: &mut TestAppContext,
2306    ) -> [Box<ViewHandle<TestItem>>; COUNT] {
2307        pane.update(cx, |pane, _| {
2308            pane.items.clear();
2309        });
2310
2311        workspace.update(cx, |workspace, cx| {
2312            let mut active_item_index = 0;
2313
2314            let mut index = 0;
2315            let items = labels.map(|mut label| {
2316                if label.ends_with("*") {
2317                    label = label.trim_end_matches("*");
2318                    active_item_index = index;
2319                }
2320
2321                let labeled_item = Box::new(cx.add_view(|_| TestItem::new().with_label(label)));
2322                Pane::add_item(
2323                    workspace,
2324                    pane,
2325                    labeled_item.clone(),
2326                    false,
2327                    false,
2328                    None,
2329                    cx,
2330                );
2331                index += 1;
2332                labeled_item
2333            });
2334
2335            pane.update(cx, |pane, cx| {
2336                pane.activate_item(active_item_index, false, false, cx)
2337            });
2338
2339            items
2340        })
2341    }
2342
2343    // Assert the item label, with the active item label suffixed with a '*'
2344    fn assert_item_labels<const COUNT: usize>(
2345        pane: &ViewHandle<Pane>,
2346        expected_states: [&str; COUNT],
2347        cx: &mut TestAppContext,
2348    ) {
2349        pane.read_with(cx, |pane, cx| {
2350            let actual_states = pane
2351                .items
2352                .iter()
2353                .enumerate()
2354                .map(|(ix, item)| {
2355                    let mut state = item
2356                        .as_any()
2357                        .downcast_ref::<TestItem>()
2358                        .unwrap()
2359                        .read(cx)
2360                        .label
2361                        .clone();
2362                    if ix == pane.active_item_index {
2363                        state.push('*');
2364                    }
2365                    state
2366                })
2367                .collect::<Vec<_>>();
2368
2369            assert_eq!(
2370                actual_states, expected_states,
2371                "pane items do not match expectation"
2372            );
2373        })
2374    }
2375}