Persist selections for editors (#25083)

Part of #7371
Closes #12853

Release Notes:

- Started to persist latest selections for editors, to restore those on
restart

crates/editor/src/display_map.rs

@@ -2778,6 +2778,7 @@ pub mod tests {
     fn init_test(cx: &mut App, f: impl Fn(&mut AllLanguageSettingsContent)) {
         let settings = SettingsStore::test(cx);
         cx.set_global(settings);
+        workspace::init_settings(cx);
         language::init(cx);
         crate::init(cx);
         Project::init_settings(cx);

crates/editor/src/editor.rs

@@ -106,6 +106,7 @@ use language::{
 use language::{point_to_lsp, BufferRow, CharClassifier, Runnable, RunnableRange};
 use linked_editing_ranges::refresh_linked_ranges;
 use mouse_context_menu::MouseContextMenu;
+use persistence::DB;
 pub use proposed_changes_editor::{
     ProposedChangeLocation, ProposedChangesEditor, ProposedChangesEditorToolbar,
 };
@@ -171,8 +172,14 @@ use ui::{
     Tooltip,
 };
 use util::{defer, maybe, post_inc, RangeExt, ResultExt, TryFutureExt};
-use workspace::item::{ItemHandle, PreviewTabsSettings};
-use workspace::notifications::{DetachAndPromptErr, NotificationId, NotifyTaskExt};
+use workspace::{
+    item::{ItemHandle, PreviewTabsSettings},
+    ItemId, RestoreOnStartupBehavior,
+};
+use workspace::{
+    notifications::{DetachAndPromptErr, NotificationId, NotifyTaskExt},
+    WorkspaceSettings,
+};
 use workspace::{
     searchable::SearchEvent, ItemNavHistory, SplitDirection, ViewId, Workspace, WorkspaceId,
 };
@@ -763,6 +770,7 @@ pub struct Editor {
     selection_mark_mode: bool,
     toggle_fold_multiple_buffers: Task<()>,
     _scroll_cursor_center_top_bottom_task: Task<()>,
+    serialize_selections: Task<()>,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Default)]
@@ -1475,6 +1483,7 @@ impl Editor {
             _scroll_cursor_center_top_bottom_task: Task::ready(()),
             selection_mark_mode: false,
             toggle_fold_multiple_buffers: Task::ready(()),
+            serialize_selections: Task::ready(()),
             text_style_refinement: None,
             load_diff_task: load_uncommitted_diff,
         };
@@ -2181,9 +2190,37 @@ impl Editor {
         self.blink_manager.update(cx, BlinkManager::pause_blinking);
         cx.emit(EditorEvent::SelectionsChanged { local });
 
-        if self.selections.disjoint_anchors().len() == 1 {
+        let selections = &self.selections.disjoint;
+        if selections.len() == 1 {
             cx.emit(SearchEvent::ActiveMatchChanged)
         }
+        if local
+            && WorkspaceSettings::get(None, cx).restore_on_startup != RestoreOnStartupBehavior::None
+        {
+            if let Some(workspace_id) = self.workspace.as_ref().and_then(|workspace| workspace.1) {
+                let background_executor = cx.background_executor().clone();
+                let editor_id = cx.entity().entity_id().as_u64() as ItemId;
+                let snapshot = self.buffer().read(cx).snapshot(cx);
+                let selections = selections.clone();
+                self.serialize_selections = cx.background_spawn(async move {
+                    background_executor.timer(Duration::from_millis(100)).await;
+                    let selections = selections
+                        .iter()
+                        .map(|selection| {
+                            (
+                                selection.start.to_offset(&snapshot),
+                                selection.end.to_offset(&snapshot),
+                            )
+                        })
+                        .collect();
+                    DB.save_editor_selections(editor_id, workspace_id, selections)
+                        .await
+                        .context("persisting editor selections")
+                        .log_err();
+                });
+            }
+        }
+
         cx.notify();
     }
 
@@ -2197,7 +2234,7 @@ impl Editor {
         self.change_selections_inner(autoscroll, true, window, cx, change)
     }
 
-    pub fn change_selections_inner<R>(
+    fn change_selections_inner<R>(
         &mut self,
         autoscroll: Option<Autoscroll>,
         request_completions: bool,
@@ -14982,6 +15019,31 @@ impl Editor {
     pub fn wait_for_diff_to_load(&self) -> Option<Shared<Task<()>>> {
         self.load_diff_task.clone()
     }
+
+    fn read_selections_from_db(
+        &mut self,
+        item_id: u64,
+        workspace_id: WorkspaceId,
+        window: &mut Window,
+        cx: &mut Context<Editor>,
+    ) {
+        if WorkspaceSettings::get(None, cx).restore_on_startup == RestoreOnStartupBehavior::None {
+            return;
+        }
+        let Some(selections) = DB.get_editor_selections(item_id, workspace_id).log_err() else {
+            return;
+        };
+        if selections.is_empty() {
+            return;
+        }
+
+        let snapshot = self.buffer.read(cx).snapshot(cx);
+        self.change_selections(None, window, cx, |s| {
+            s.select_ranges(selections.into_iter().map(|(start, end)| {
+                snapshot.clip_offset(start, Bias::Left)..snapshot.clip_offset(end, Bias::Right)
+            }));
+        });
+    }
 }
 
 fn get_uncommitted_diff_for_buffer(

crates/editor/src/items.rs

@@ -1079,6 +1079,7 @@ impl SerializableItem for Editor {
                         cx.new(|cx| {
                             let mut editor = Editor::for_buffer(buffer, Some(project), window, cx);
 
+                            editor.read_selections_from_db(item_id, workspace_id, window, cx);
                             editor.read_scroll_position_from_db(item_id, workspace_id, window, cx);
                             editor
                         })
@@ -1134,6 +1135,12 @@ impl SerializableItem for Editor {
                                     let mut editor =
                                         Editor::for_buffer(buffer, Some(project), window, cx);
 
+                                    editor.read_selections_from_db(
+                                        item_id,
+                                        workspace_id,
+                                        window,
+                                        cx,
+                                    );
                                     editor.read_scroll_position_from_db(
                                         item_id,
                                         workspace_id,
@@ -1152,6 +1159,7 @@ impl SerializableItem for Editor {
                         window.spawn(cx, |mut cx| async move {
                             let editor = open_by_abs_path?.await?.downcast::<Editor>().with_context(|| format!("Failed to downcast to Editor after opening abs path {abs_path:?}"))?;
                             editor.update_in(&mut cx, |editor, window, cx| {
+                                editor.read_selections_from_db(item_id, workspace_id, window, cx);
                                 editor.read_scroll_position_from_db(item_id, workspace_id, window, cx);
                             })?;
                             Ok(editor)

crates/editor/src/movement.rs

@@ -1184,6 +1184,7 @@ mod tests {
     fn init_test(cx: &mut gpui::App) {
         let settings_store = SettingsStore::test(cx);
         cx.set_global(settings_store);
+        workspace::init_settings(cx);
         theme::init(theme::LoadThemes::JustBase, cx);
         language::init(cx);
         crate::init(cx);

crates/editor/src/persistence.rs

@@ -2,6 +2,7 @@ use anyhow::Result;
 use db::sqlez::bindable::{Bind, Column, StaticColumnCount};
 use db::sqlez::statement::Statement;
 use fs::MTime;
+use itertools::Itertools as _;
 use std::path::PathBuf;
 
 use db::sqlez_macros::sql;
@@ -134,9 +135,26 @@ define_connection!(
             ALTER TABLE editors ADD COLUMN mtime_seconds INTEGER DEFAULT NULL;
             ALTER TABLE editors ADD COLUMN mtime_nanos INTEGER DEFAULT NULL;
         ),
+        sql! (
+            CREATE TABLE editor_selections (
+                item_id INTEGER NOT NULL,
+                editor_id INTEGER NOT NULL,
+                workspace_id INTEGER NOT NULL,
+                start INTEGER NOT NULL,
+                end INTEGER NOT NULL,
+                PRIMARY KEY(item_id),
+                FOREIGN KEY(editor_id, workspace_id) REFERENCES editors(item_id, workspace_id)
+                ON DELETE CASCADE
+            ) STRICT;
+        ),
     ];
 );
 
+// https://www.sqlite.org/limits.html
+// > <..> the maximum value of a host parameter number is SQLITE_MAX_VARIABLE_NUMBER,
+// > which defaults to <..> 32766 for SQLite versions after 3.32.0.
+const MAX_QUERY_PLACEHOLDERS: usize = 32000;
+
 impl EditorDb {
     query! {
         pub fn get_serialized_editor(item_id: ItemId, workspace_id: WorkspaceId) -> Result<Option<SerializedEditor>> {
@@ -188,6 +206,68 @@ impl EditorDb {
         }
     }
 
+    query! {
+        pub fn get_editor_selections(
+            editor_id: ItemId,
+            workspace_id: WorkspaceId
+        ) -> Result<Vec<(usize, usize)>> {
+            SELECT start, end
+            FROM editor_selections
+            WHERE editor_id = ?1 AND workspace_id = ?2
+        }
+    }
+
+    pub async fn save_editor_selections(
+        &self,
+        editor_id: ItemId,
+        workspace_id: WorkspaceId,
+        selections: Vec<(usize, usize)>,
+    ) -> Result<()> {
+        let mut first_selection;
+        let mut last_selection = 0_usize;
+        for (count, placeholders) in std::iter::once("(?1, ?2, ?, ?)")
+            .cycle()
+            .take(selections.len())
+            .chunks(MAX_QUERY_PLACEHOLDERS / 4)
+            .into_iter()
+            .map(|chunk| {
+                let mut count = 0;
+                let placeholders = chunk
+                    .inspect(|_| {
+                        count += 1;
+                    })
+                    .join(", ");
+                (count, placeholders)
+            })
+            .collect::<Vec<_>>()
+        {
+            first_selection = last_selection;
+            last_selection = last_selection + count;
+            let query = format!(
+                r#"
+DELETE FROM editor_selections WHERE editor_id = ?1 AND workspace_id = ?2;
+
+INSERT INTO editor_selections (editor_id, workspace_id, start, end)
+VALUES {placeholders};
+"#
+            );
+
+            let selections = selections[first_selection..last_selection].to_vec();
+            self.write(move |conn| {
+                let mut statement = Statement::prepare(conn, query)?;
+                statement.bind(&editor_id, 1)?;
+                let mut next_index = statement.bind(&workspace_id, 2)?;
+                for (start, end) in selections {
+                    next_index = statement.bind(&start, next_index)?;
+                    next_index = statement.bind(&end, next_index)?;
+                }
+                statement.exec()
+            })
+            .await?;
+        }
+        Ok(())
+    }
+
     pub async fn delete_unloaded_items(
         &self,
         workspace: WorkspaceId,

crates/language_tools/src/lsp_log_tests.rs

@@ -109,6 +109,7 @@ fn init_test(cx: &mut gpui::TestAppContext) {
     cx.update(|cx| {
         let settings_store = SettingsStore::test(cx);
         cx.set_global(settings_store);
+        workspace::init_settings(cx);
         theme::init(theme::LoadThemes::JustBase, cx);
         release_channel::init(SemanticVersion::default(), cx);
         language::init(cx);

crates/search/src/buffer_search.rs

@@ -1511,6 +1511,7 @@ mod tests {
         cx.update(|cx| {
             let store = settings::SettingsStore::test(cx);
             cx.set_global(store);
+            workspace::init_settings(cx);
             editor::init(cx);
 
             language::init(cx);

crates/workspace/src/workspace_settings.rs

@@ -71,7 +71,7 @@ impl CloseWindowWhenNoItems {
     }
 }
 
-#[derive(Copy, Clone, Default, Serialize, Deserialize, JsonSchema)]
+#[derive(Copy, Clone, PartialEq, Eq, Default, Serialize, Deserialize, JsonSchema)]
 #[serde(rename_all = "snake_case")]
 pub enum RestoreOnStartupBehavior {
     /// Always start with an empty editor