Project Diff 2 (#23891)

This adds a new version of the project diff editor to go alongside the
new git panel.

The basics seem to be working, but still todo:

* [ ] Fix untracked files
* [ ] Fix deleted files
* [ ] Show commit message editor at top
* [x] Handle empty state
* [x] Fix panic where locator sometimes seeks to wrong excerpt

Release Notes:

- N/A

crates/git_ui/Cargo.toml

@@ -17,11 +17,14 @@ anyhow.workspace = true
 collections.workspace = true
 db.workspace = true
 editor.workspace = true
+feature_flags.workspace = true
 futures.workspace = true
 git.workspace = true
 gpui.workspace = true
 language.workspace = true
+multi_buffer.workspace = true
 menu.workspace = true
+postage.workspace = true
 project.workspace = true
 rpc.workspace = true
 schemars.workspace = true

crates/git_ui/src/git_panel.rs

@@ -1,5 +1,6 @@
 use crate::git_panel_settings::StatusStyle;
 use crate::repository_selector::RepositorySelectorPopoverMenu;
+use crate::ProjectDiff;
 use crate::{
     git_panel_settings::GitPanelSettings, git_status_icon, repository_selector::RepositorySelector,
 };
@@ -207,31 +208,6 @@ fn commit_message_editor(
 }
 
 impl GitPanel {
-    pub fn load(
-        workspace: WeakEntity<Workspace>,
-        cx: AsyncWindowContext,
-    ) -> Task<Result<Entity<Self>>> {
-        cx.spawn(|mut cx| async move {
-            let commit_message_buffer = workspace.update(&mut cx, |workspace, cx| {
-                let project = workspace.project();
-                let active_repository = project.read(cx).active_repository(cx);
-                active_repository
-                    .map(|active_repository| commit_message_buffer(project, &active_repository, cx))
-            })?;
-            let commit_message_buffer = match commit_message_buffer {
-                Some(commit_message_buffer) => Some(
-                    commit_message_buffer
-                        .await
-                        .context("opening commit buffer")?,
-                ),
-                None => None,
-            };
-            workspace.update_in(&mut cx, |workspace, window, cx| {
-                Self::new(workspace, window, commit_message_buffer, cx)
-            })
-        })
-    }
-
     pub fn new(
         workspace: &mut Workspace,
         window: &mut Window,
@@ -240,7 +216,7 @@ impl GitPanel {
     ) -> Entity<Self> {
         let fs = workspace.app_state().fs.clone();
         let project = workspace.project().clone();
-        let git_state = project.read(cx).git_state().cloned();
+        let git_state = project.read(cx).git_state().clone();
         let active_repository = project.read(cx).active_repository(cx);
         let (err_sender, mut err_receiver) = mpsc::channel(1);
         let workspace = cx.entity().downgrade();
@@ -261,19 +237,17 @@ impl GitPanel {
 
             let scroll_handle = UniformListScrollHandle::new();
 
-            if let Some(git_state) = git_state {
-                cx.subscribe_in(
-                    &git_state,
-                    window,
-                    move |this, git_state, event, window, cx| match event {
-                        project::git::Event::RepositoriesUpdated => {
-                            this.active_repository = git_state.read(cx).active_repository();
-                            this.schedule_update(window, cx);
-                        }
-                    },
-                )
-                .detach();
-            }
+            cx.subscribe_in(
+                &git_state,
+                window,
+                move |this, git_state, event, window, cx| match event {
+                    project::git::Event::RepositoriesUpdated => {
+                        this.active_repository = git_state.read(cx).active_repository();
+                        this.schedule_update(window, cx);
+                    }
+                },
+            )
+            .detach();
 
             let repository_selector =
                 cx.new(|cx| RepositorySelector::new(project.clone(), window, cx));
@@ -344,8 +318,24 @@ impl GitPanel {
         git_panel
     }
 
+    pub fn set_focused_path(&mut self, path: ProjectPath, _: &mut Window, cx: &mut Context<Self>) {
+        let Some(git_repo) = self.active_repository.as_ref() else {
+            return;
+        };
+        let Some(repo_path) = git_repo.project_path_to_repo_path(&path) else {
+            return;
+        };
+        let Ok(ix) = self
+            .visible_entries
+            .binary_search_by_key(&&repo_path, |entry| &entry.repo_path)
+        else {
+            return;
+        };
+        self.selected_entry = Some(ix);
+        cx.notify();
+    }
+
     fn serialize(&mut self, cx: &mut Context<Self>) {
-        // TODO: we can store stage status here
         let width = self.width;
         self.pending_serialization = cx.background_executor().spawn(
             async move {
@@ -623,7 +613,7 @@ impl GitPanel {
         let Some(active_repository) = self.active_repository.as_ref() else {
             return;
         };
-        let Some(path) = active_repository.unrelativize(&entry.repo_path) else {
+        let Some(path) = active_repository.repo_path_to_project_path(&entry.repo_path) else {
             return;
         };
         let path_exists = self.project.update(cx, |project, cx| {
@@ -1021,8 +1011,8 @@ impl GitPanel {
             .project
             .read(cx)
             .git_state()
-            .map(|state| state.read(cx).all_repositories())
-            .unwrap_or_default();
+            .read(cx)
+            .all_repositories();
         let entry_count = self
             .active_repository
             .as_ref()
@@ -1408,17 +1398,26 @@ impl GitPanel {
                 .toggle_state(selected)
                 .disabled(!has_write_access)
                 .on_click({
-                    let handle = cx.entity().downgrade();
-                    move |_, window, cx| {
-                        let Some(this) = handle.upgrade() else {
+                    let repo_path = entry_details.repo_path.clone();
+                    cx.listener(move |this, _, window, cx| {
+                        this.selected_entry = Some(ix);
+                        window.dispatch_action(Box::new(OpenSelected), cx);
+                        cx.notify();
+                        let Some(workspace) = this.workspace.upgrade() else {
                             return;
                         };
-                        this.update(cx, |this, cx| {
-                            this.selected_entry = Some(ix);
-                            window.dispatch_action(Box::new(OpenSelected), cx);
-                            cx.notify();
-                        });
-                    }
+                        let Some(git_repo) = this.active_repository.as_ref() else {
+                            return;
+                        };
+                        let Some(path) = git_repo.repo_path_to_project_path(&repo_path).and_then(
+                            |project_path| this.project.read(cx).absolute_path(&project_path, cx),
+                        ) else {
+                            return;
+                        };
+                        workspace.update(cx, |workspace, cx| {
+                            ProjectDiff::deploy_at(workspace, Some(path.into()), window, cx);
+                        })
+                    })
                 })
                 .child(
                     h_flex()

crates/git_ui/src/git_ui.rs

@@ -2,14 +2,17 @@ use ::settings::Settings;
 use git::status::FileStatus;
 use git_panel_settings::GitPanelSettings;
 use gpui::App;
+use project_diff::ProjectDiff;
 use ui::{ActiveTheme, Color, Icon, IconName, IntoElement};
 
 pub mod git_panel;
 mod git_panel_settings;
+pub mod project_diff;
 pub mod repository_selector;
 
 pub fn init(cx: &mut App) {
     GitPanelSettings::register(cx);
+    cx.observe_new(ProjectDiff::register).detach();
 }
 
 // TODO: Add updated status colors to theme

crates/git_ui/src/project_diff.rs

@@ -0,0 +1,495 @@
+use std::{
+    any::{Any, TypeId},
+    path::Path,
+    sync::Arc,
+};
+
+use anyhow::Result;
+use collections::HashSet;
+use editor::{scroll::Autoscroll, Editor, EditorEvent};
+use feature_flags::FeatureFlagViewExt;
+use futures::StreamExt;
+use gpui::{
+    actions, AnyElement, AnyView, App, AppContext, AsyncWindowContext, Entity, EventEmitter,
+    FocusHandle, Focusable, Render, Subscription, Task, WeakEntity,
+};
+use language::{Anchor, Buffer, Capability, OffsetRangeExt};
+use multi_buffer::MultiBuffer;
+use project::{buffer_store::BufferChangeSet, git::GitState, Project, ProjectPath};
+use theme::ActiveTheme;
+use ui::prelude::*;
+use util::ResultExt as _;
+use workspace::{
+    item::{BreadcrumbText, Item, ItemEvent, ItemHandle, TabContentParams},
+    searchable::SearchableItemHandle,
+    ItemNavHistory, ToolbarItemLocation, Workspace,
+};
+
+use crate::git_panel::GitPanel;
+
+actions!(git, [ShowUncommittedChanges]);
+
+pub(crate) struct ProjectDiff {
+    multibuffer: Entity<MultiBuffer>,
+    editor: Entity<Editor>,
+    project: Entity<Project>,
+    git_state: Entity<GitState>,
+    workspace: WeakEntity<Workspace>,
+    focus_handle: FocusHandle,
+    update_needed: postage::watch::Sender<()>,
+    pending_scroll: Option<Arc<Path>>,
+
+    _task: Task<Result<()>>,
+    _subscription: Subscription,
+}
+
+struct DiffBuffer {
+    abs_path: Arc<Path>,
+    buffer: Entity<Buffer>,
+    change_set: Entity<BufferChangeSet>,
+}
+
+impl ProjectDiff {
+    pub(crate) fn register(
+        _: &mut Workspace,
+        window: Option<&mut Window>,
+        cx: &mut Context<Workspace>,
+    ) {
+        let Some(window) = window else { return };
+        cx.when_flag_enabled::<feature_flags::GitUiFeatureFlag>(window, |workspace, _, _cx| {
+            workspace.register_action(Self::deploy);
+        });
+    }
+
+    fn deploy(
+        workspace: &mut Workspace,
+        _: &ShowUncommittedChanges,
+        window: &mut Window,
+        cx: &mut Context<Workspace>,
+    ) {
+        Self::deploy_at(workspace, None, window, cx)
+    }
+
+    pub fn deploy_at(
+        workspace: &mut Workspace,
+        path: Option<Arc<Path>>,
+        window: &mut Window,
+        cx: &mut Context<Workspace>,
+    ) {
+        let project_diff = if let Some(existing) = workspace.item_of_type::<Self>(cx) {
+            workspace.activate_item(&existing, true, true, window, cx);
+            existing
+        } else {
+            let workspace_handle = cx.entity().downgrade();
+            let project_diff =
+                cx.new(|cx| Self::new(workspace.project().clone(), workspace_handle, window, cx));
+            workspace.add_item_to_active_pane(
+                Box::new(project_diff.clone()),
+                None,
+                true,
+                window,
+                cx,
+            );
+            project_diff
+        };
+        if let Some(path) = path {
+            project_diff.update(cx, |project_diff, cx| {
+                project_diff.scroll_to(path, window, cx);
+            })
+        }
+    }
+
+    fn new(
+        project: Entity<Project>,
+        workspace: WeakEntity<Workspace>,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> Self {
+        let focus_handle = cx.focus_handle();
+        let multibuffer = cx.new(|_| MultiBuffer::new(Capability::ReadWrite));
+
+        let editor = cx.new(|cx| {
+            let mut diff_display_editor = Editor::for_multibuffer(
+                multibuffer.clone(),
+                Some(project.clone()),
+                true,
+                window,
+                cx,
+            );
+            diff_display_editor.set_expand_all_diff_hunks(cx);
+            diff_display_editor
+        });
+        cx.subscribe_in(&editor, window, Self::handle_editor_event)
+            .detach();
+
+        let git_state = project.read(cx).git_state().clone();
+        let git_state_subscription = cx.subscribe_in(
+            &git_state,
+            window,
+            move |this, _git_state, event, _window, _cx| match event {
+                project::git::Event::RepositoriesUpdated => {
+                    *this.update_needed.borrow_mut() = ();
+                }
+            },
+        );
+
+        let (mut send, recv) = postage::watch::channel::<()>();
+        let worker = window.spawn(cx, {
+            let this = cx.weak_entity();
+            |cx| Self::handle_status_updates(this, recv, cx)
+        });
+        // Kick of a refresh immediately
+        *send.borrow_mut() = ();
+
+        Self {
+            project,
+            git_state: git_state.clone(),
+            workspace,
+            focus_handle,
+            editor,
+            multibuffer,
+            pending_scroll: None,
+            update_needed: send,
+            _task: worker,
+            _subscription: git_state_subscription,
+        }
+    }
+
+    pub fn scroll_to(&mut self, path: Arc<Path>, window: &mut Window, cx: &mut Context<Self>) {
+        if let Some(position) = self.multibuffer.read(cx).location_for_path(&path, cx) {
+            self.editor.update(cx, |editor, cx| {
+                editor.change_selections(Some(Autoscroll::focused()), window, cx, |s| {
+                    s.select_ranges([position..position]);
+                })
+            })
+        } else {
+            self.pending_scroll = Some(path);
+        }
+    }
+
+    fn handle_editor_event(
+        &mut self,
+        editor: &Entity<Editor>,
+        event: &EditorEvent,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        match event {
+            EditorEvent::ScrollPositionChanged { .. } => editor.update(cx, |editor, cx| {
+                let anchor = editor.scroll_manager.anchor().anchor;
+                let Some((_, buffer, _)) = self.multibuffer.read(cx).excerpt_containing(anchor, cx)
+                else {
+                    return;
+                };
+                let Some(project_path) = buffer
+                    .read(cx)
+                    .file()
+                    .map(|file| (file.worktree_id(cx), file.path().clone()))
+                else {
+                    return;
+                };
+                self.workspace
+                    .update(cx, |workspace, cx| {
+                        if let Some(git_panel) = workspace.panel::<GitPanel>(cx) {
+                            git_panel.update(cx, |git_panel, cx| {
+                                git_panel.set_focused_path(project_path.into(), window, cx)
+                            })
+                        }
+                    })
+                    .ok();
+            }),
+            _ => {}
+        }
+    }
+
+    fn load_buffers(&mut self, cx: &mut Context<Self>) -> Vec<Task<Result<DiffBuffer>>> {
+        let Some(repo) = self.git_state.read(cx).active_repository() else {
+            self.multibuffer.update(cx, |multibuffer, cx| {
+                multibuffer.clear(cx);
+            });
+            return vec![];
+        };
+
+        let mut previous_paths = self.multibuffer.read(cx).paths().collect::<HashSet<_>>();
+
+        let mut result = vec![];
+        for entry in repo.status() {
+            if !entry.status.has_changes() {
+                continue;
+            }
+            let Some(project_path) = repo.repo_path_to_project_path(&entry.repo_path) else {
+                continue;
+            };
+            let Some(abs_path) = self.project.read(cx).absolute_path(&project_path, cx) else {
+                continue;
+            };
+            let abs_path = Arc::from(abs_path);
+
+            previous_paths.remove(&abs_path);
+            let load_buffer = self
+                .project
+                .update(cx, |project, cx| project.open_buffer(project_path, cx));
+
+            let project = self.project.clone();
+            result.push(cx.spawn(|_, mut cx| async move {
+                let buffer = load_buffer.await?;
+                let changes = project
+                    .update(&mut cx, |project, cx| {
+                        project.open_unstaged_changes(buffer.clone(), cx)
+                    })?
+                    .await?;
+                Ok(DiffBuffer {
+                    abs_path,
+                    buffer,
+                    change_set: changes,
+                })
+            }));
+        }
+        self.multibuffer.update(cx, |multibuffer, cx| {
+            for path in previous_paths {
+                multibuffer.remove_excerpts_for_path(path, cx);
+            }
+        });
+        result
+    }
+
+    fn register_buffer(
+        &mut self,
+        diff_buffer: DiffBuffer,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        let abs_path = diff_buffer.abs_path;
+        let buffer = diff_buffer.buffer;
+        let change_set = diff_buffer.change_set;
+
+        let snapshot = buffer.read(cx).snapshot();
+        let diff_hunk_ranges = change_set
+            .read(cx)
+            .diff_hunks_intersecting_range(Anchor::MIN..Anchor::MAX, &snapshot)
+            .map(|diff_hunk| diff_hunk.buffer_range.to_point(&snapshot))
+            .collect::<Vec<_>>();
+
+        self.multibuffer.update(cx, |multibuffer, cx| {
+            multibuffer.set_excerpts_for_path(
+                abs_path.clone(),
+                buffer,
+                diff_hunk_ranges,
+                editor::DEFAULT_MULTIBUFFER_CONTEXT,
+                cx,
+            );
+        });
+        if self.pending_scroll.as_ref() == Some(&abs_path) {
+            self.scroll_to(abs_path, window, cx);
+        }
+    }
+
+    pub async fn handle_status_updates(
+        this: WeakEntity<Self>,
+        mut recv: postage::watch::Receiver<()>,
+        mut cx: AsyncWindowContext,
+    ) -> Result<()> {
+        while let Some(_) = recv.next().await {
+            let buffers_to_load = this.update(&mut cx, |this, cx| this.load_buffers(cx))?;
+            for buffer_to_load in buffers_to_load {
+                if let Some(buffer) = buffer_to_load.await.log_err() {
+                    cx.update(|window, cx| {
+                        this.update(cx, |this, cx| this.register_buffer(buffer, window, cx))
+                            .ok();
+                    })?;
+                }
+            }
+            this.update(&mut cx, |this, _| this.pending_scroll.take())?;
+        }
+
+        Ok(())
+    }
+}
+
+impl EventEmitter<EditorEvent> for ProjectDiff {}
+
+impl Focusable for ProjectDiff {
+    fn focus_handle(&self, _: &App) -> FocusHandle {
+        self.focus_handle.clone()
+    }
+}
+
+impl Item for ProjectDiff {
+    type Event = EditorEvent;
+
+    fn to_item_events(event: &EditorEvent, f: impl FnMut(ItemEvent)) {
+        Editor::to_item_events(event, f)
+    }
+
+    fn deactivated(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        self.editor
+            .update(cx, |editor, cx| editor.deactivated(window, cx));
+    }
+
+    fn navigate(
+        &mut self,
+        data: Box<dyn Any>,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> bool {
+        self.editor
+            .update(cx, |editor, cx| editor.navigate(data, window, cx))
+    }
+
+    fn tab_tooltip_text(&self, _: &App) -> Option<SharedString> {
+        Some("Project Diff".into())
+    }
+
+    fn tab_content(&self, params: TabContentParams, _window: &Window, _: &App) -> AnyElement {
+        Label::new("Uncommitted Changes")
+            .color(if params.selected {
+                Color::Default
+            } else {
+                Color::Muted
+            })
+            .into_any_element()
+    }
+
+    fn telemetry_event_text(&self) -> Option<&'static str> {
+        Some("project diagnostics")
+    }
+
+    fn as_searchable(&self, _: &Entity<Self>) -> Option<Box<dyn SearchableItemHandle>> {
+        Some(Box::new(self.editor.clone()))
+    }
+
+    fn for_each_project_item(
+        &self,
+        cx: &App,
+        f: &mut dyn FnMut(gpui::EntityId, &dyn project::ProjectItem),
+    ) {
+        self.editor.for_each_project_item(cx, f)
+    }
+
+    fn is_singleton(&self, _: &App) -> bool {
+        false
+    }
+
+    fn set_nav_history(
+        &mut self,
+        nav_history: ItemNavHistory,
+        _: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.editor.update(cx, |editor, _| {
+            editor.set_nav_history(Some(nav_history));
+        });
+    }
+
+    fn clone_on_split(
+        &self,
+        _workspace_id: Option<workspace::WorkspaceId>,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> Option<Entity<Self>>
+    where
+        Self: Sized,
+    {
+        Some(
+            cx.new(|cx| ProjectDiff::new(self.project.clone(), self.workspace.clone(), window, cx)),
+        )
+    }
+
+    fn is_dirty(&self, cx: &App) -> bool {
+        self.multibuffer.read(cx).is_dirty(cx)
+    }
+
+    fn has_conflict(&self, cx: &App) -> bool {
+        self.multibuffer.read(cx).has_conflict(cx)
+    }
+
+    fn can_save(&self, _: &App) -> bool {
+        true
+    }
+
+    fn save(
+        &mut self,
+        format: bool,
+        project: Entity<Project>,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> Task<Result<()>> {
+        self.editor.save(format, project, window, cx)
+    }
+
+    fn save_as(
+        &mut self,
+        _: Entity<Project>,
+        _: ProjectPath,
+        _window: &mut Window,
+        _: &mut Context<Self>,
+    ) -> Task<Result<()>> {
+        unreachable!()
+    }
+
+    fn reload(
+        &mut self,
+        project: Entity<Project>,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> Task<Result<()>> {
+        self.editor.reload(project, window, cx)
+    }
+
+    fn act_as_type<'a>(
+        &'a self,
+        type_id: TypeId,
+        self_handle: &'a Entity<Self>,
+        _: &'a App,
+    ) -> Option<AnyView> {
+        if type_id == TypeId::of::<Self>() {
+            Some(self_handle.to_any())
+        } else if type_id == TypeId::of::<Editor>() {
+            Some(self.editor.to_any())
+        } else {
+            None
+        }
+    }
+
+    fn breadcrumb_location(&self, _: &App) -> ToolbarItemLocation {
+        ToolbarItemLocation::PrimaryLeft
+    }
+
+    fn breadcrumbs(&self, theme: &theme::Theme, cx: &App) -> Option<Vec<BreadcrumbText>> {
+        self.editor.breadcrumbs(theme, cx)
+    }
+
+    fn added_to_workspace(
+        &mut self,
+        workspace: &mut Workspace,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.editor.update(cx, |editor, cx| {
+            editor.added_to_workspace(workspace, window, cx)
+        });
+    }
+}
+
+impl Render for ProjectDiff {
+    fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        let is_empty = self.multibuffer.read(cx).is_empty();
+        if is_empty {
+            div()
+                .bg(cx.theme().colors().editor_background)
+                .flex()
+                .items_center()
+                .justify_center()
+                .size_full()
+                .child(Label::new("No uncommitted changes"))
+        } else {
+            div()
+                .bg(cx.theme().colors().editor_background)
+                .flex()
+                .items_center()
+                .justify_center()
+                .size_full()
+                .child(self.editor.clone())
+        }
+    }
+}

crates/git_ui/src/repository_selector.rs

@@ -20,10 +20,8 @@ pub struct RepositorySelector {
 
 impl RepositorySelector {
     pub fn new(project: Entity<Project>, window: &mut Window, cx: &mut Context<Self>) -> Self {
-        let git_state = project.read(cx).git_state().cloned();
-        let all_repositories = git_state
-            .as_ref()
-            .map_or(vec![], |git_state| git_state.read(cx).all_repositories());
+        let git_state = project.read(cx).git_state().clone();
+        let all_repositories = git_state.read(cx).all_repositories();
         let filtered_repositories = all_repositories.clone();
         let delegate = RepositorySelectorDelegate {
             project: project.downgrade(),
@@ -38,11 +36,8 @@ impl RepositorySelector {
                 .max_height(Some(rems(20.).into()))
         });
 
-        let _subscriptions = if let Some(git_state) = git_state {
-            vec![cx.subscribe_in(&git_state, window, Self::handle_project_git_event)]
-        } else {
-            Vec::new()
-        };
+        let _subscriptions =
+            vec![cx.subscribe_in(&git_state, window, Self::handle_project_git_event)];
 
         RepositorySelector {
             picker,