From bacfed37b798a57936b5c9901925b62da824b622 Mon Sep 17 00:00:00 2001
From: Keith Simmons <keith@zed.dev>
Date: Thu, 19 May 2022 11:22:53 -0700
Subject: [PATCH] Clone selections on editor split

---
 crates/editor/src/editor.rs                | 46 +++++++++++++++++++---
 crates/editor/src/element.rs               |  4 +-
 crates/editor/src/selections_collection.rs |  1 +
 3 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/crates/editor/src/editor.rs b/crates/editor/src/editor.rs
index 9b160acf646737d63d6fa99eb2ab3aa1ffed41ae..c9e4732f9fcab55cbbf75b36ba04e9d796b994e3 100644
--- a/crates/editor/src/editor.rs
+++ b/crates/editor/src/editor.rs
@@ -862,7 +862,14 @@ impl Editor {
     ) -> Self {
         let buffer = cx.add_model(|cx| Buffer::new(0, String::new(), cx));
         let buffer = cx.add_model(|cx| MultiBuffer::singleton(buffer, cx));
-        Self::new(EditorMode::SingleLine, buffer, None, field_editor_style, cx)
+        Self::new(
+            EditorMode::SingleLine,
+            buffer,
+            None,
+            field_editor_style,
+            None,
+            cx,
+        )
     }
 
     pub fn auto_height(
@@ -877,6 +884,7 @@ impl Editor {
             buffer,
             None,
             field_editor_style,
+            None,
             cx,
         )
     }
@@ -887,7 +895,7 @@ impl Editor {
         cx: &mut ViewContext<Self>,
     ) -> Self {
         let buffer = cx.add_model(|cx| MultiBuffer::singleton(buffer, cx));
-        Self::new(EditorMode::Full, buffer, project, None, cx)
+        Self::new(EditorMode::Full, buffer, project, None, None, cx)
     }
 
     pub fn for_multibuffer(
@@ -895,7 +903,7 @@ impl Editor {
         project: Option<ModelHandle<Project>>,
         cx: &mut ViewContext<Self>,
     ) -> Self {
-        Self::new(EditorMode::Full, buffer, project, None, cx)
+        Self::new(EditorMode::Full, buffer, project, None, None, cx)
     }
 
     pub fn clone(&self, cx: &mut ViewContext<Self>) -> Self {
@@ -904,6 +912,7 @@ impl Editor {
             self.buffer.clone(),
             self.project.clone(),
             self.get_field_editor_theme,
+            Some(self.selections.clone()),
             cx,
         );
         clone.scroll_position = self.scroll_position;
@@ -917,6 +926,7 @@ impl Editor {
         buffer: ModelHandle<MultiBuffer>,
         project: Option<ModelHandle<Project>>,
         get_field_editor_theme: Option<GetFieldEditorTheme>,
+        selections: Option<SelectionsCollection>,
         cx: &mut ViewContext<Self>,
     ) -> Self {
         let display_map = cx.add_model(|cx| {
@@ -937,7 +947,8 @@ impl Editor {
         cx.observe(&display_map, Self::on_display_map_changed)
             .detach();
 
-        let selections = SelectionsCollection::new(display_map.clone(), buffer.clone());
+        let selections = selections
+            .unwrap_or_else(|| SelectionsCollection::new(display_map.clone(), buffer.clone()));
 
         let mut this = Self {
             handle: cx.weak_handle(),
@@ -6025,7 +6036,10 @@ mod tests {
     use std::{cell::RefCell, rc::Rc, time::Instant};
     use text::Point;
     use unindent::Unindent;
-    use util::test::{marked_text_by, marked_text_ranges, marked_text_ranges_by, sample_text};
+    use util::{
+        assert_set_eq,
+        test::{marked_text_by, marked_text_ranges, marked_text_ranges_by, sample_text},
+    };
     use workspace::{FollowableItem, ItemHandle};
 
     #[gpui::test]
@@ -6304,6 +6318,26 @@ mod tests {
         });
     }
 
+    #[gpui::test]
+    fn test_clone_with_selections(cx: &mut gpui::MutableAppContext) {
+        let (text, selection_ranges) = marked_text_ranges(indoc! {"
+            The qu[ick brown
+            fox jum]ps over
+            the lazy dog
+        "});
+        cx.set_global(Settings::test(cx));
+        let buffer = MultiBuffer::build_simple(&text, cx);
+
+        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, cx));
+
+        let cloned_editor = view.update(cx, |view, cx| {
+            view.change_selections(None, cx, |s| s.select_ranges(selection_ranges.clone()));
+            view.clone(cx)
+        });
+
+        assert_set_eq!(cloned_editor.selections.ranges(cx), selection_ranges);
+    }
+
     #[gpui::test]
     fn test_navigation_history(cx: &mut gpui::MutableAppContext) {
         cx.set_global(Settings::test(cx));
@@ -9765,7 +9799,7 @@ mod tests {
     }
 
     fn build_editor(buffer: ModelHandle<MultiBuffer>, cx: &mut ViewContext<Editor>) -> Editor {
-        Editor::new(EditorMode::Full, buffer, None, None, cx)
+        Editor::new(EditorMode::Full, buffer, None, None, None, cx)
     }
 
     fn assert_selection_ranges(
diff --git a/crates/editor/src/element.rs b/crates/editor/src/element.rs
index d3d67060f20f32c2c19e945d6d1cd7b99455a1f1..355d1f44337c9c855625ecc0255e51b57ee5db4b 100644
--- a/crates/editor/src/element.rs
+++ b/crates/editor/src/element.rs
@@ -1517,7 +1517,7 @@ mod tests {
         cx.set_global(Settings::test(cx));
         let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
         let (window_id, editor) = cx.add_window(Default::default(), |cx| {
-            Editor::new(EditorMode::Full, buffer, None, None, cx)
+            Editor::new(EditorMode::Full, buffer, None, None, None, cx)
         });
         let element = EditorElement::new(
             editor.downgrade(),
@@ -1539,7 +1539,7 @@ mod tests {
         cx.set_global(Settings::test(cx));
         let buffer = MultiBuffer::build_simple("", cx);
         let (window_id, editor) = cx.add_window(Default::default(), |cx| {
-            Editor::new(EditorMode::Full, buffer, None, None, cx)
+            Editor::new(EditorMode::Full, buffer, None, None, None, cx)
         });
 
         editor.update(cx, |editor, cx| {
diff --git a/crates/editor/src/selections_collection.rs b/crates/editor/src/selections_collection.rs
index aabfb676ff8be09aaa49352b2be17b2176570c0f..07fa2cd9b501d4e5964ddf776be12bc22a7bb87f 100644
--- a/crates/editor/src/selections_collection.rs
+++ b/crates/editor/src/selections_collection.rs
@@ -22,6 +22,7 @@ pub struct PendingSelection {
     pub mode: SelectMode,
 }
 
+#[derive(Clone)]
 pub struct SelectionsCollection {
     display_map: ModelHandle<DisplayMap>,
     buffer: ModelHandle<MultiBuffer>,