Do not serialize buffers containing bundled files (#38102)

Fix bundled file persistence by introducing SerializationMode enum

Closes: #38094

What's the issue?

Opening bundled files like Default Key Bindings
(zed://settings/keymap-default.json) was causing SQLite foreign key
constraint errors. The editor was trying to save state for these
read-only assets just like regular files, but since bundled files don't
have database entries, the foreign key constraint would fail.

The fix

Replaced the boolean serialize_dirty_buffers flag with a type-safe
SerializationMode enum:

```rust
pub enum SerializationMode {
    Enabled,   // Regular files persist across sessions
    Disabled,  // Bundled files don't persist
}
```

This prevents serialization at the source: workspace_id() returns None
for disabled editors, serialize() bails early, and should_serialize()
returns false. When opening bundled files, we set the mode to Disabled
from the start, so they're treated as transient views that never
interact with the persistence layer.

Changes

- editor.rs: Added SerializationMode enum and updated serialization
methods to respect it
- items.rs: Guarded should_serialize() to prevent disabled editors from
being serialized
- zed.rs: Set SerializationMode::Disabled in open_bundled_file()

Result

Bundled files open cleanly without SQLite errors and don't persist
across workspace reloads (expected behavior). Regular file persistence
remains unaffected.

Release Notes: Fixed SQLite foreign key constraint errors when opening
bundled files like Default Key Bindings.

---------

Co-authored-by: MrSubidubi <finn@zed.dev>

crates/editor/src/editor.rs

@@ -812,6 +812,22 @@ impl MinimapVisibility {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BufferSerialization {
+    All,
+    NonDirtyBuffers,
+}
+
+impl BufferSerialization {
+    fn new(restore_unsaved_buffers: bool) -> Self {
+        if restore_unsaved_buffers {
+            Self::All
+        } else {
+            Self::NonDirtyBuffers
+        }
+    }
+}
+
 #[derive(Clone, Debug)]
 struct RunnableTasks {
     templates: Vec<(TaskSourceKind, TaskTemplate)>,
@@ -1129,7 +1145,7 @@ pub struct Editor {
     show_git_blame_inline_delay_task: Option<Task<()>>,
     git_blame_inline_enabled: bool,
     render_diff_hunk_controls: RenderDiffHunkControlsFn,
-    serialize_dirty_buffers: bool,
+    buffer_serialization: Option<BufferSerialization>,
     show_selection_menu: Option<bool>,
     blame: Option<Entity<GitBlame>>,
     blame_subscription: Option<Subscription>,
@@ -2205,10 +2221,13 @@ impl Editor {
             git_blame_inline_enabled: full_mode
                 && ProjectSettings::get_global(cx).git.inline_blame.enabled,
             render_diff_hunk_controls: Arc::new(render_diff_hunk_controls),
-            serialize_dirty_buffers: !is_minimap
-                && ProjectSettings::get_global(cx)
-                    .session
-                    .restore_unsaved_buffers,
+            buffer_serialization: is_minimap.not().then(|| {
+                BufferSerialization::new(
+                    ProjectSettings::get_global(cx)
+                        .session
+                        .restore_unsaved_buffers,
+                )
+            }),
             blame: None,
             blame_subscription: None,
             tasks: BTreeMap::default(),
@@ -2752,6 +2771,14 @@ impl Editor {
         self.workspace.as_ref()?.0.upgrade()
     }
 
+    /// Returns the workspace serialization ID if this editor should be serialized.
+    fn workspace_serialization_id(&self, _cx: &App) -> Option<WorkspaceId> {
+        self.workspace
+            .as_ref()
+            .filter(|_| self.should_serialize_buffer())
+            .and_then(|workspace| workspace.1)
+    }
+
     pub fn title<'a>(&self, cx: &'a App) -> Cow<'a, str> {
         self.buffer().read(cx).title(cx)
     }
@@ -3000,6 +3027,20 @@ impl Editor {
         self.auto_replace_emoji_shortcode = auto_replace;
     }
 
+    pub fn set_should_serialize(&mut self, should_serialize: bool, cx: &App) {
+        self.buffer_serialization = should_serialize.then(|| {
+            BufferSerialization::new(
+                ProjectSettings::get_global(cx)
+                    .session
+                    .restore_unsaved_buffers,
+            )
+        })
+    }
+
+    fn should_serialize_buffer(&self) -> bool {
+        self.buffer_serialization.is_some()
+    }
+
     pub fn toggle_edit_predictions(
         &mut self,
         _: &ToggleEditPrediction,
@@ -3216,8 +3257,7 @@ impl Editor {
             });
 
             if WorkspaceSettings::get(None, cx).restore_on_startup != RestoreOnStartupBehavior::None
-                && let Some(workspace_id) =
-                    self.workspace.as_ref().and_then(|workspace| workspace.1)
+                && let Some(workspace_id) = self.workspace_serialization_id(cx)
             {
                 let snapshot = self.buffer().read(cx).snapshot(cx);
                 let selections = selections.clone();
@@ -3282,7 +3322,7 @@ impl Editor {
             data.folds = inmemory_folds;
         });
 
-        let Some(workspace_id) = self.workspace.as_ref().and_then(|workspace| workspace.1) else {
+        let Some(workspace_id) = self.workspace_serialization_id(cx) else {
             return;
         };
         let background_executor = cx.background_executor().clone();
@@ -21179,8 +21219,9 @@ impl Editor {
         }
 
         let project_settings = ProjectSettings::get_global(cx);
-        self.serialize_dirty_buffers =
-            !self.mode.is_minimap() && project_settings.session.restore_unsaved_buffers;
+        self.buffer_serialization = self
+            .should_serialize_buffer()
+            .then(|| BufferSerialization::new(project_settings.session.restore_unsaved_buffers));
 
         if self.mode.is_full() {
             let show_inline_diagnostics = project_settings.diagnostics.inline.enabled;

crates/editor/src/items.rs

@@ -1,7 +1,7 @@
 use crate::{
-    Anchor, Autoscroll, Editor, EditorEvent, EditorSettings, ExcerptId, ExcerptRange, FormatTarget,
-    MultiBuffer, MultiBufferSnapshot, NavigationData, ReportEditorEvent, SearchWithinRange,
-    SelectionEffects, ToPoint as _,
+    Anchor, Autoscroll, BufferSerialization, Editor, EditorEvent, EditorSettings, ExcerptId,
+    ExcerptRange, FormatTarget, MultiBuffer, MultiBufferSnapshot, NavigationData,
+    ReportEditorEvent, SearchWithinRange, SelectionEffects, ToPoint as _,
     display_map::HighlightKey,
     editor_settings::SeedQuerySetting,
     persistence::{DB, SerializedEditor},
@@ -1256,17 +1256,15 @@ impl SerializableItem for Editor {
         window: &mut Window,
         cx: &mut Context<Self>,
     ) -> Option<Task<Result<()>>> {
-        if self.mode.is_minimap() {
-            return None;
-        }
-        let mut serialize_dirty_buffers = self.serialize_dirty_buffers;
-
+        let buffer_serialization = self.buffer_serialization?;
         let project = self.project.clone()?;
-        if project.read(cx).visible_worktrees(cx).next().is_none() {
+
+        let serialize_dirty_buffers = match buffer_serialization {
             // If we don't have a worktree, we don't serialize, because
             // projects without worktrees aren't deserialized.
-            serialize_dirty_buffers = false;
-        }
+            BufferSerialization::All => project.read(cx).visible_worktrees(cx).next().is_some(),
+            BufferSerialization::NonDirtyBuffers => false,
+        };
 
         if closing && !serialize_dirty_buffers {
             return None;
@@ -1323,10 +1321,11 @@ impl SerializableItem for Editor {
     }
 
     fn should_serialize(&self, event: &Self::Event) -> bool {
-        matches!(
-            event,
-            EditorEvent::Saved | EditorEvent::DirtyChanged | EditorEvent::BufferEdited
-        )
+        self.should_serialize_buffer()
+            && matches!(
+                event,
+                EditorEvent::Saved | EditorEvent::DirtyChanged | EditorEvent::BufferEdited
+            )
     }
 }
 

crates/zed/src/zed.rs

@@ -1922,6 +1922,7 @@ fn open_bundled_file(
                             let mut editor =
                                 Editor::for_multibuffer(buffer, Some(project.clone()), window, cx);
                             editor.set_read_only(true);
+                            editor.set_should_serialize(false, cx);
                             editor.set_breadcrumb_header(title.into());
                             editor
                         })),