From 8328fe926d34d12031cb50db47a9dd39ed681a84 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bla=C5=BE=20Hrastnik?= <blaz@mxxn.io>
Date: Tue, 23 Mar 2021 17:47:40 +0900
Subject: [PATCH] Drop refcell use, make view simply ref doc.id.

---
 helix-term/src/application.rs |   4 +-
 helix-term/src/commands.rs    | 214 +++++++++++++++++-----------------
 helix-term/src/ui/editor.rs   |  27 +++--
 helix-term/src/ui/mod.rs      |  71 ++++++-----
 helix-view/src/document.rs    |   4 +
 helix-view/src/editor.rs      |  72 ++++++++----
 helix-view/src/tree.rs        |  14 ++-
 helix-view/src/view.rs        |  22 ++--
 8 files changed, 234 insertions(+), 194 deletions(-)

diff --git a/helix-term/src/application.rs b/helix-term/src/application.rs
index 8af963a9..38c0d88a 100644
--- a/helix-term/src/application.rs
+++ b/helix-term/src/application.rs
@@ -129,10 +129,9 @@ impl Application {
                             .editor
                             .documents
                             .iter_mut()
-                            .find(|(_, doc)| doc.borrow().path() == path.as_ref());
+                            .find(|(_, doc)| doc.path() == path.as_ref());
 
                         if let Some((_, doc)) = doc {
-                            let mut doc = doc.borrow_mut();
                             let text = doc.text();
 
                             let diagnostics = params
@@ -167,7 +166,6 @@ impl Application {
                                 .collect();
 
                             doc.diagnostics = diagnostics;
-                            drop(doc);
                             // TODO: we want to process all the events in queue, then render. publishDiagnostic tends to send a whole bunch of events
                             self.render();
                         }
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index fd95bca4..9544b0e0 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -41,8 +41,9 @@ impl<'a> Context<'a> {
     }
 
     #[inline]
-    pub fn doc(&mut self) -> std::cell::RefMut<Document> {
-        self.editor.view().doc.borrow_mut()
+    pub fn doc(&mut self) -> &mut Document {
+        let id = self.editor.view().doc;
+        &mut self.editor.documents[id]
     }
 
     /// Push a new component onto the compositor.
@@ -72,7 +73,7 @@ pub type Command = fn(cx: &mut Context);
 
 pub fn move_char_left(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_horizontally(
@@ -88,7 +89,7 @@ pub fn move_char_left(cx: &mut Context) {
 
 pub fn move_char_right(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_horizontally(
@@ -104,7 +105,7 @@ pub fn move_char_right(cx: &mut Context) {
 
 pub fn move_line_up(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_vertically(
@@ -120,7 +121,7 @@ pub fn move_line_up(cx: &mut Context) {
 
 pub fn move_line_down(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_vertically(
@@ -135,7 +136,7 @@ pub fn move_line_down(cx: &mut Context) {
 }
 
 pub fn move_line_end(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let lines = selection_lines(doc.text(), doc.selection());
 
     let positions = lines
@@ -155,7 +156,7 @@ pub fn move_line_end(cx: &mut Context) {
 }
 
 pub fn move_line_start(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let lines = selection_lines(doc.text(), doc.selection());
 
     let positions = lines
@@ -177,7 +178,7 @@ pub fn move_line_start(cx: &mut Context) {
 
 pub fn move_next_word_start(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|range| {
@@ -190,7 +191,7 @@ pub fn move_next_word_start(cx: &mut Context) {
 
 pub fn move_prev_word_start(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|range| {
@@ -203,7 +204,7 @@ pub fn move_prev_word_start(cx: &mut Context) {
 
 pub fn move_next_word_end(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|range| {
@@ -215,14 +216,14 @@ pub fn move_next_word_end(cx: &mut Context) {
 }
 
 pub fn move_file_start(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     doc.set_selection(Selection::point(0));
 
     doc.mode = Mode::Normal;
 }
 
 pub fn move_file_end(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text();
     let last_line = text.line_to_char(text.len_lines().saturating_sub(2));
     doc.set_selection(Selection::point(last_line));
@@ -232,7 +233,7 @@ pub fn move_file_end(cx: &mut Context) {
 
 pub fn extend_next_word_start(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|mut range| {
@@ -245,7 +246,7 @@ pub fn extend_next_word_start(cx: &mut Context) {
 
 pub fn extend_prev_word_start(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|mut range| {
@@ -257,7 +258,7 @@ pub fn extend_prev_word_start(cx: &mut Context) {
 
 pub fn extend_next_word_end(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
 
     let selection = doc.selection().transform(|mut range| {
@@ -286,7 +287,7 @@ where
             ..
         } = event
         {
-            let mut doc = cx.doc();
+            let doc = cx.doc();
             let text = doc.text().slice(..);
 
             let selection = doc.selection().transform(|mut range| {
@@ -390,7 +391,7 @@ pub fn replace(cx: &mut Context) {
         {
             let text = Tendril::from_char(ch);
 
-            let mut doc = cx.doc();
+            let doc = cx.doc();
 
             let transaction =
                 Transaction::change_by_selection(doc.text(), doc.selection(), |range| {
@@ -403,15 +404,14 @@ pub fn replace(cx: &mut Context) {
     })
 }
 
-fn scroll(view: &mut View, offset: usize, direction: Direction) {
+fn scroll(cx: &mut Context, offset: usize, direction: Direction) {
     use Direction::*;
-    // we use short lived borrows since view's methods read from doc too
-    let doc = view.doc.borrow();
-    let text = doc.text().slice(..);
+    let view = cx.editor.view();
+    let doc = cx.editor.document(view.doc).unwrap();
     let cursor = coords_at_pos(doc.text().slice(..), doc.selection().cursor());
     let doc_last_line = doc.text().len_lines() - 1;
 
-    let last_line = view.last_line();
+    let last_line = view.last_line(doc);
 
     if direction == Backward && view.first_line == 0
         || direction == Forward && last_line == doc_last_line
@@ -424,6 +424,9 @@ fn scroll(view: &mut View, offset: usize, direction: Direction) {
     // cursor visual offset
     let cursor_off = cursor.row - view.first_line;
 
+    // upgrade to mut reference
+    let view = cx.editor.view_mut();
+
     view.first_line = match direction {
         Forward => view.first_line + offset,
         Backward => view.first_line.saturating_sub(offset),
@@ -433,37 +436,47 @@ fn scroll(view: &mut View, offset: usize, direction: Direction) {
     // clamp into viewport
     let line = (view.first_line + cursor_off).clamp(
         view.first_line + scrolloff,
-        view.last_line().saturating_sub(scrolloff),
+        last_line.saturating_sub(scrolloff),
     );
 
+    // view drops here
+
+    // upgrade to mut reference
+    let doc = cx.doc();
+
+    let text = doc.text().slice(..);
     let pos = pos_at_coords(text, Position::new(line, cursor.col)); // this func will properly truncate to line end
-    drop(doc); // upgrade to mutable borrow
-    view.doc.borrow_mut().set_selection(Selection::point(pos));
+
+    doc.set_selection(Selection::point(pos));
 }
 
 pub fn page_up(cx: &mut Context) {
     let view = cx.view();
-    scroll(view, view.area.height as usize, Direction::Backward);
+    let offset = view.area.height as usize;
+    scroll(cx, offset, Direction::Backward);
 }
 
 pub fn page_down(cx: &mut Context) {
     let view = cx.view();
-    scroll(view, view.area.height as usize, Direction::Forward);
+    let offset = view.area.height as usize;
+    scroll(cx, offset, Direction::Forward);
 }
 
 pub fn half_page_up(cx: &mut Context) {
     let view = cx.view();
-    scroll(view, view.area.height as usize / 2, Direction::Backward);
+    let offset = view.area.height as usize / 2;
+    scroll(cx, offset, Direction::Backward);
 }
 
 pub fn half_page_down(cx: &mut Context) {
     let view = cx.view();
-    scroll(view, view.area.height as usize / 2, Direction::Forward);
+    let offset = view.area.height as usize / 2;
+    scroll(cx, offset, Direction::Forward);
 }
 
 pub fn extend_char_left(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_horizontally(
@@ -479,7 +492,7 @@ pub fn extend_char_left(cx: &mut Context) {
 
 pub fn extend_char_right(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_horizontally(
@@ -495,7 +508,7 @@ pub fn extend_char_right(cx: &mut Context) {
 
 pub fn extend_line_up(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_vertically(
@@ -511,7 +524,7 @@ pub fn extend_line_up(cx: &mut Context) {
 
 pub fn extend_line_down(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     let selection = doc.selection().transform(|range| {
         movement::move_vertically(
@@ -526,7 +539,7 @@ pub fn extend_line_down(cx: &mut Context) {
 }
 
 pub fn select_all(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let end = doc.text().len_chars().saturating_sub(1);
     doc.set_selection(Selection::single(0, end))
@@ -554,7 +567,7 @@ pub fn split_selection(cx: &mut Context) {
 }
 
 pub fn split_selection_on_newline(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text().slice(..);
     // only compile the regex once
     #[allow(clippy::trivial_regex)]
@@ -586,14 +599,13 @@ fn _search(doc: &mut Document, contents: &str, regex: &Regex) {
 
 // TODO: use one function for search vs extend
 pub fn search(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     // TODO: could probably share with select_on_matches?
 
     // HAXX: sadly we can't avoid allocating a single string for the whole buffer since we can't
     // feed chunks into the regex yet
     let contents = doc.text().slice(..).to_string();
-    drop(doc);
 
     let prompt = ui::regex_prompt(cx, "search:".to_string(), move |doc, regex| {
         let text = doc.text();
@@ -610,20 +622,19 @@ pub fn search(cx: &mut Context) {
 pub fn search_next(cx: &mut Context) {
     if let Some(query) = register::get('\\') {
         let query = query.first().unwrap();
-        let mut doc = cx.doc();
+        let doc = cx.doc();
         let contents = doc.text().slice(..).to_string();
         let regex = Regex::new(&query).unwrap();
-        _search(&mut doc, &contents, &regex);
+        _search(doc, &contents, &regex);
     }
 }
 
 pub fn search_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let contents = doc.text().slice(..);
     let query = doc.selection().primary().fragment(contents);
     let regex = regex::escape(&query);
     register::set('\\', vec![regex]);
-    drop(doc);
     search_next(cx);
 }
 
@@ -635,7 +646,7 @@ pub fn search_selection(cx: &mut Context) {
 
 pub fn select_line(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let pos = doc.selection().primary();
     let text = doc.text();
@@ -648,7 +659,7 @@ pub fn select_line(cx: &mut Context) {
 }
 pub fn extend_line(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let pos = doc.selection().primary();
     let text = doc.text();
@@ -676,21 +687,20 @@ fn _delete_selection(doc: &mut Document) {
 }
 
 pub fn delete_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
-    _delete_selection(&mut doc);
+    let doc = cx.doc();
+    _delete_selection(doc);
 
     doc.append_changes_to_history();
 }
 
 pub fn change_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
-    _delete_selection(&mut doc);
-    drop(doc);
+    let doc = cx.doc();
+    _delete_selection(doc);
     insert_mode(cx);
 }
 
 pub fn collapse_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let selection = doc
         .selection()
         .transform(|range| Range::new(range.head, range.head));
@@ -699,7 +709,7 @@ pub fn collapse_selection(cx: &mut Context) {
 }
 
 pub fn flip_selections(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let selection = doc
         .selection()
         .transform(|range| Range::new(range.head, range.anchor));
@@ -713,8 +723,8 @@ fn enter_insert_mode(doc: &mut Document) {
 
 // inserts at the start of each selection
 pub fn insert_mode(cx: &mut Context) {
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
 
     let selection = doc
         .selection()
@@ -724,8 +734,8 @@ pub fn insert_mode(cx: &mut Context) {
 
 // inserts at the end of each selection
 pub fn append_mode(cx: &mut Context) {
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
     doc.restore_cursor = true;
 
     let text = doc.text().slice(..);
@@ -792,7 +802,9 @@ pub fn command_mode(cx: &mut Context) {
                 }
                 ["w"] | ["write"] => {
                     // TODO: non-blocking via save() command
-                    smol::block_on(editor.view().doc.borrow().save());
+                    let id = editor.view().doc;
+                    let doc = &mut editor.document(id).unwrap();
+                    smol::block_on(doc.save());
                 }
 
                 _ => (),
@@ -807,8 +819,9 @@ pub fn file_picker(cx: &mut Context) {
 }
 
 pub fn buffer_picker(cx: &mut Context) {
-    unimplemented!()
-    // let picker = ui::buffer_picker(&editor.views, editor.focus);
+    // let documents = cx.editor.documents.iter().map(||).collect();
+    // (document_id, relative_path/name) mappings
+    // let picker = ui::buffer_picker(&documents, editor.focus);
     // cx.push_layer(Box::new(picker));
 }
 
@@ -827,18 +840,16 @@ fn selection_lines(doc: &Rope, selection: &Selection) -> Vec<usize> {
 
 // I inserts at the start of each line with a selection
 pub fn prepend_to_line(cx: &mut Context) {
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
-    drop(doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
 
     move_line_start(cx);
 }
 
 // A inserts at the end of each line with a selection
 pub fn append_to_line(cx: &mut Context) {
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
-    drop(doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
 
     move_line_end(cx);
 }
@@ -846,8 +857,8 @@ pub fn append_to_line(cx: &mut Context) {
 // o inserts a new line after each line with a selection
 pub fn open_below(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
 
     let lines = selection_lines(doc.text(), doc.selection());
 
@@ -897,8 +908,8 @@ pub fn open_below(cx: &mut Context) {
 // O inserts a new line before each line with a selection
 pub fn open_above(cx: &mut Context) {
     let count = cx.count;
-    let mut doc = cx.doc();
-    enter_insert_mode(&mut doc);
+    let doc = cx.doc();
+    enter_insert_mode(doc);
 
     let lines = selection_lines(doc.text(), doc.selection());
 
@@ -947,7 +958,7 @@ pub fn open_above(cx: &mut Context) {
 }
 
 pub fn normal_mode(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     doc.mode = Mode::Normal;
 
@@ -986,7 +997,7 @@ fn goto(cx: &mut Context, locations: Vec<lsp::Location>) {
     match locations.as_slice() {
         [location] => {
             cx.editor.open(PathBuf::from(location.uri.path()));
-            let mut doc = cx.doc();
+            let doc = cx.doc();
             let definition_pos = location.range.start;
             let new_pos = helix_lsp::util::lsp_pos_to_pos(doc.text(), definition_pos);
             doc.set_selection(Selection::point(new_pos));
@@ -1003,7 +1014,8 @@ fn goto(cx: &mut Context, locations: Vec<lsp::Location>) {
                 move |editor: &mut Editor, item| {
                     editor.open(PathBuf::from(item.uri.path()));
                     // TODO: issues with doc already being broo
-                    let mut doc = &mut editor.view().doc.borrow_mut();
+                    let id = editor.view().doc;
+                    let doc = &mut editor.documents[id];
                     let definition_pos = item.range.start;
                     let new_pos = helix_lsp::util::lsp_pos_to_pos(doc.text(), definition_pos);
                     doc.set_selection(Selection::point(new_pos));
@@ -1015,7 +1027,7 @@ fn goto(cx: &mut Context, locations: Vec<lsp::Location>) {
 }
 
 pub fn goto_definition(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
         None => return,
@@ -1027,12 +1039,11 @@ pub fn goto_definition(cx: &mut Context) {
     // TODO: handle fails
     let res =
         smol::block_on(language_server.goto_definition(doc.identifier(), pos)).unwrap_or_default();
-    drop(doc);
     goto(cx, res);
 }
 
 pub fn goto_type_definition(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
         None => return,
@@ -1044,12 +1055,11 @@ pub fn goto_type_definition(cx: &mut Context) {
     // TODO: handle fails
     let res = smol::block_on(language_server.goto_type_definition(doc.identifier(), pos))
         .unwrap_or_default();
-    drop(doc);
     goto(cx, res);
 }
 
 pub fn goto_implementation(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
         None => return,
@@ -1061,12 +1071,11 @@ pub fn goto_implementation(cx: &mut Context) {
     // TODO: handle fails
     let res = smol::block_on(language_server.goto_implementation(doc.identifier(), pos))
         .unwrap_or_default();
-    drop(doc);
     goto(cx, res);
 }
 
 pub fn goto_reference(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
         None => return,
@@ -1078,7 +1087,6 @@ pub fn goto_reference(cx: &mut Context) {
     // TODO: handle fails
     let res =
         smol::block_on(language_server.goto_reference(doc.identifier(), pos)).unwrap_or_default();
-    drop(doc);
     goto(cx, res);
 }
 
@@ -1092,7 +1100,7 @@ pub mod insert {
 
     // TODO: insert means add text just before cursor, on exit we should be on the last letter.
     pub fn insert_char(cx: &mut Context, c: char) {
-        let mut doc = cx.doc();
+        let doc = cx.doc();
 
         // run through insert hooks, stopping on the first one that returns Some(t)
         for hook in HOOKS {
@@ -1109,7 +1117,7 @@ pub mod insert {
     }
 
     pub fn insert_tab(cx: &mut Context) {
-        let mut doc = cx.doc();
+        let doc = cx.doc();
         // TODO: round out to nearest indentation level (for example a line with 3 spaces should
         // indent by one to reach 4 spaces).
 
@@ -1119,7 +1127,7 @@ pub mod insert {
     }
 
     pub fn insert_newline(cx: &mut Context) {
-        let mut doc = cx.doc();
+        let doc = cx.doc();
         let text = doc.text().slice(..);
         let transaction = Transaction::change_by_selection(doc.text(), doc.selection(), |range| {
             let indent_level =
@@ -1136,7 +1144,7 @@ pub mod insert {
     // TODO: handle indent-aware delete
     pub fn delete_char_backward(cx: &mut Context) {
         let count = cx.count;
-        let mut doc = cx.doc();
+        let doc = cx.doc();
         let text = doc.text().slice(..);
         let transaction = Transaction::change_by_selection(doc.text(), doc.selection(), |range| {
             (
@@ -1150,7 +1158,7 @@ pub mod insert {
 
     pub fn delete_char_forward(cx: &mut Context) {
         let count = cx.count;
-        let mut doc = cx.doc();
+        let doc = cx.doc();
         let text = doc.text().slice(..);
         let transaction = Transaction::change_by_selection(doc.text(), doc.selection(), |range| {
             (
@@ -1180,7 +1188,7 @@ pub fn redo(cx: &mut Context) {
 
 pub fn yank(cx: &mut Context) {
     // TODO: should selections be made end inclusive?
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let values = doc
         .selection()
         .fragments(doc.text().slice(..))
@@ -1221,7 +1229,7 @@ pub fn paste(cx: &mut Context) {
 
         let mut values = values.into_iter().map(Tendril::from).chain(repeat);
 
-        let mut doc = cx.doc();
+        let doc = cx.doc();
 
         let transaction = if linewise {
             // paste on the next line
@@ -1260,8 +1268,8 @@ fn get_lines(doc: &Document) -> Vec<usize> {
 }
 
 pub fn indent(cx: &mut Context) {
-    let mut doc = cx.doc();
-    let lines = get_lines(&mut doc);
+    let doc = cx.doc();
+    let lines = get_lines(doc);
 
     // Indent by one level
     let indent = Tendril::from(doc.indent_unit());
@@ -1278,8 +1286,8 @@ pub fn indent(cx: &mut Context) {
 }
 
 pub fn unindent(cx: &mut Context) {
-    let mut doc = cx.doc();
-    let lines = get_lines(&mut doc);
+    let doc = cx.doc();
+    let lines = get_lines(doc);
     let mut changes = Vec::with_capacity(lines.len());
     let tab_width = doc.tab_width();
 
@@ -1313,7 +1321,7 @@ pub fn unindent(cx: &mut Context) {
 
 pub fn format_selections(cx: &mut Context) {
     use helix_lsp::lsp;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     // via lsp if available
     // else via tree-sitter indentation calculations
@@ -1351,7 +1359,7 @@ pub fn format_selections(cx: &mut Context) {
 
 pub fn join_selections(cx: &mut Context) {
     use movement::skip_over_next;
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let text = doc.text();
     let slice = doc.text().slice(..);
 
@@ -1407,7 +1415,7 @@ pub fn keep_selections(cx: &mut Context) {
 }
 
 pub fn keep_primary_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let range = doc.selection().primary();
     let selection = Selection::single(range.anchor, range.head);
@@ -1424,7 +1432,7 @@ pub fn save(cx: &mut Context) {
 }
 
 pub fn completion(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
@@ -1438,8 +1446,6 @@ pub fn completion(cx: &mut Context) {
 
     let res = smol::block_on(language_server.completion(doc.identifier(), pos)).unwrap_or_default();
 
-    drop(doc);
-
     // TODO: if no completion, show some message or something
     if !res.is_empty() {
         // let snapshot = doc.state.clone();
@@ -1455,11 +1461,13 @@ pub fn completion(cx: &mut Context) {
                 match event {
                     PromptEvent::Abort => {
                         // revert state
-                        let doc = &mut editor.view().doc.borrow_mut();
+                        // let id = editor.view().doc;
+                        // let doc = &mut editor.documents[id];
                         // doc.state = snapshot.clone();
                     }
                     PromptEvent::Validate => {
-                        let doc = &mut editor.view().doc.borrow_mut();
+                        let id = editor.view().doc;
+                        let doc = &mut editor.documents[id];
 
                         // revert state to what it was before the last update
                         // doc.state = snapshot.clone();
@@ -1525,7 +1533,7 @@ pub fn completion(cx: &mut Context) {
 pub fn hover(cx: &mut Context) {
     use helix_lsp::lsp;
 
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     let language_server = match doc.language_server() {
         Some(language_server) => language_server,
@@ -1542,8 +1550,6 @@ pub fn hover(cx: &mut Context) {
     let res = smol::block_on(language_server.text_document_hover(doc.identifier(), pos))
         .unwrap_or_default();
 
-    drop(doc);
-
     if let Some(hover) = res {
         // hover.contents / .range <- used for visualizing
         let contents = match hover.contents {
@@ -1574,7 +1580,7 @@ pub fn next_view(cx: &mut Context) {
 
 // comments
 pub fn toggle_comments(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
     let transaction = comment::toggle_line_comments(doc.text(), doc.selection());
 
     doc.apply(&transaction);
@@ -1584,7 +1590,7 @@ pub fn toggle_comments(cx: &mut Context) {
 // tree sitter node selection
 
 pub fn expand_selection(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     if let Some(syntax) = doc.syntax() {
         let text = doc.text().slice(..);
@@ -1594,7 +1600,7 @@ pub fn expand_selection(cx: &mut Context) {
 }
 
 pub fn match_brackets(cx: &mut Context) {
-    let mut doc = cx.doc();
+    let doc = cx.doc();
 
     if let Some(syntax) = doc.syntax() {
         let pos = doc.selection().cursor();
diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index 0302742d..ba9eda42 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -39,6 +39,7 @@ impl EditorView {
     }
     pub fn render_view(
         &self,
+        doc: &Document,
         view: &View,
         viewport: Rect,
         surface: &mut Surface,
@@ -51,13 +52,12 @@ impl EditorView {
             viewport.width - OFFSET,
             viewport.height.saturating_sub(1),
         ); // - 1 for statusline
-        self.render_buffer(view, area, surface, theme, is_focused);
+        self.render_buffer(&doc, view, area, surface, theme, is_focused);
 
         // clear with background color
         // TODO: this seems to prevent setting style later
         // surface.set_style(viewport, theme.get("ui.background"));
 
-        let doc = view.doc.borrow();
         self.render_diagnostics(&doc, area, surface, theme, is_focused);
 
         let area = Rect::new(
@@ -71,16 +71,16 @@ impl EditorView {
 
     pub fn render_buffer(
         &self,
+        doc: &Document,
         view: &View,
         viewport: Rect,
         surface: &mut Surface,
         theme: &Theme,
         is_focused: bool,
     ) {
-        let doc = view.doc.borrow();
         let text = doc.text().slice(..);
 
-        let last_line = view.last_line();
+        let last_line = view.last_line(doc);
 
         let range = {
             // calculate viewport byte ranges
@@ -211,16 +211,14 @@ impl EditorView {
             // let selection_style = Style::default().bg(Color::Rgb(94, 0, 128));
             let selection_style = Style::default().bg(Color::Rgb(84, 0, 153));
 
-            for selection in view
-                .doc
-                .borrow()
+            for selection in doc
                 .selection()
                 .iter()
                 .filter(|range| range.overlaps(&screen))
             {
                 // TODO: render also if only one of the ranges is in viewport
-                let mut start = view.screen_coords_at_pos(text, selection.anchor);
-                let mut end = view.screen_coords_at_pos(text, selection.head);
+                let mut start = view.screen_coords_at_pos(doc, text, selection.anchor);
+                let mut end = view.screen_coords_at_pos(doc, text, selection.head);
 
                 // cursor
                 if let Some(end) = end {
@@ -292,7 +290,6 @@ impl EditorView {
         let info: Style = theme.get("info");
         let hint: Style = theme.get("hint");
 
-        let last_line = view.last_line();
         for (i, line) in (view.first_line..last_line).enumerate() {
             use helix_core::diagnostic::Severity;
             if let Some(diagnostic) = doc.diagnostics.iter().find(|d| d.line == line) {
@@ -431,11 +428,12 @@ impl Component for EditorView {
         match event {
             Event::Resize(width, height) => {
                 // HAXX: offset the render area height by 1 to account for prompt/commandline
-                cx.editor.tree.resize(Rect::new(0, 0, width, height - 1));
+                cx.editor.resize(Rect::new(0, 0, width, height - 1));
                 EventResult::Consumed(None)
             }
             Event::Key(event) => {
-                let mode = cx.editor.view().doc.borrow().mode();
+                let id = cx.editor.view().doc;
+                let mode = cx.editor.document(id).unwrap().mode();
 
                 let mut cxt = commands::Context {
                     editor: &mut cx.editor,
@@ -491,7 +489,7 @@ impl Component for EditorView {
                 // appease borrowck
                 let callback = cxt.callback.take();
                 drop(cxt);
-                cx.editor.view_mut().ensure_cursor_in_view();
+                cx.editor.ensure_cursor_in_view(cx.editor.tree.focus);
 
                 EventResult::Consumed(callback)
             }
@@ -501,7 +499,8 @@ impl Component for EditorView {
 
     fn render(&self, mut area: Rect, surface: &mut Surface, cx: &mut Context) {
         for (view, is_focused) in cx.editor.tree.views() {
-            self.render_view(view, view.area, surface, &cx.editor.theme, is_focused);
+            let doc = cx.editor.document(view.doc).unwrap();
+            self.render_view(doc, view, view.area, surface, &cx.editor.theme, is_focused);
         }
     }
 
diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index cb1b36fa..f91a9f35 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -40,7 +40,8 @@ pub fn regex_prompt(
             match event {
                 PromptEvent::Abort => {
                     // TODO: also revert text
-                    let doc = &mut editor.view().doc.borrow_mut();
+                    let id = editor.view().doc;
+                    let doc = &mut editor.documents[id];
                     doc.set_selection(snapshot.clone());
                 }
                 PromptEvent::Validate => {
@@ -54,18 +55,17 @@ pub fn regex_prompt(
 
                     match Regex::new(input) {
                         Ok(regex) => {
-                            let view = &mut editor.view_mut();
-                            let mut doc = view.doc.borrow_mut();
+                            // let view = &mut editor.view_mut();
+                            let id = editor.view().doc;
+                            let doc = &mut editor.documents[id];
 
                             // revert state to what it was before the last update
                             // TODO: also revert text
                             doc.set_selection(snapshot.clone());
 
-                            fun(&mut doc, regex);
+                            fun(doc, regex);
 
-                            drop(doc);
-
-                            view.ensure_cursor_in_view();
+                            editor.ensure_cursor_in_view(editor.view().id);
                         }
                         Err(_err) => (), // TODO: mark command line as error
                     }
@@ -101,40 +101,39 @@ pub fn file_picker(root: &str) -> Picker<PathBuf> {
             path.strip_prefix("./").unwrap().to_str().unwrap().into()
         },
         move |editor: &mut Editor, path: &PathBuf| {
-            editor.open(path.into());
+            let document_id = editor.open(path.into()).expect("editor.open failed");
         },
     )
 }
 
 use helix_view::View;
-pub fn buffer_picker(views: &[View], current: usize) -> Picker<(Option<PathBuf>, usize)> {
-    unimplemented!();
-    // use helix_view::Editor;
-    // Picker::new(
-    //     views
-    //         .iter()
-    //         .enumerate()
-    //         .map(|(i, view)| (view.doc.relative_path().map(Path::to_path_buf), i))
-    //         .collect(),
-    //     move |(path, index): &(Option<PathBuf>, usize)| {
-    //         // format_fn
-    //         match path {
-    //             Some(path) => {
-    //                 if *index == current {
-    //                     format!("{} (*)", path.to_str().unwrap()).into()
-    //                 } else {
-    //                     path.to_str().unwrap().into()
-    //                 }
-    //             }
-    //             None => "[NEW]".into(),
-    //         }
-    //     },
-    //     |editor: &mut Editor, &(_, index): &(Option<PathBuf>, usize)| {
-    //         if index < editor.views.len() {
-    //             editor.focus = index;
-    //         }
-    //     },
-    // )
+pub fn buffer_picker(buffers: &[Document], current: usize) -> Picker<(Option<PathBuf>, usize)> {
+    use helix_view::Editor;
+    Picker::new(
+        buffers
+            .iter()
+            .enumerate()
+            .map(|(i, doc)| (doc.relative_path().map(Path::to_path_buf), i))
+            .collect(),
+        move |(path, index): &(Option<PathBuf>, usize)| {
+            // format_fn
+            match path {
+                Some(path) => {
+                    if *index == current {
+                        format!("{} (*)", path.to_str().unwrap()).into()
+                    } else {
+                        path.to_str().unwrap().into()
+                    }
+                }
+                None => "[NEW]".into(),
+            }
+        },
+        |editor: &mut Editor, &(_, index): &(Option<PathBuf>, usize)| {
+            // if index < editor.views.len() {
+            //     editor.focus = index;
+            // }
+        },
+    )
 }
 
 pub mod completers {
diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index f6c7c70d..0286b2b9 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -8,6 +8,8 @@ use helix_core::{
     ChangeSet, Diagnostic, History, Rope, Selection, State, Syntax, Transaction,
 };
 
+use crate::DocumentId;
+
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
 pub enum Mode {
     Normal,
@@ -18,6 +20,7 @@ pub enum Mode {
 
 pub struct Document {
     // rope + selection
+    pub(crate) id: DocumentId,
     state: State,
     path: Option<PathBuf>,
 
@@ -66,6 +69,7 @@ impl Document {
         let old_state = None;
 
         Self {
+            id: DocumentId::default(),
             path: None,
             state: State::new(text),
             mode: Mode::Normal,
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index 08f4183d..802ca3e1 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -1,7 +1,7 @@
 use crate::{theme::Theme, tree::Tree, Document, DocumentId, View};
+use tui::layout::Rect;
 
 use std::path::PathBuf;
-use std::{cell::RefCell, rc::Rc};
 
 use slotmap::{DefaultKey as Key, SlotMap};
 
@@ -9,7 +9,7 @@ use anyhow::Error;
 
 pub struct Editor {
     pub tree: Tree,
-    pub documents: SlotMap<DocumentId, Rc<RefCell<Document>>>,
+    pub documents: SlotMap<DocumentId, Document>,
     pub count: Option<usize>,
     pub theme: Theme,
     pub language_servers: helix_lsp::Registry,
@@ -34,18 +34,25 @@ impl Editor {
         }
     }
 
-    pub fn open(&mut self, path: PathBuf) -> Result<(), Error> {
-        // TODO: issues with doc already being borrowed if called from inside goto()
-
-        let existing_view = self
-            .tree
-            .views()
-            .find(|(view, _)| view.doc.borrow().path() == Some(&path));
-
-        if let Some((view, _)) = existing_view {
-            self.tree.focus = view.id;
-            return Ok(());
+    fn _refresh(&mut self) {
+        for (view, _) in self.tree.views_mut() {
+            let doc = &self.documents[view.doc];
+            view.ensure_cursor_in_view(doc)
         }
+    }
+
+    pub fn open(&mut self, path: PathBuf) -> Result<DocumentId, Error> {
+        let existing_view = self.documents().find(|doc| doc.path() == Some(&path));
+
+        // TODO:
+        // if view with doc, focus it
+        // else open new split
+
+        // if let Some((view, _)) = existing_view {
+        //     let id = view.doc.id;
+        //     self.tree.focus = view.id;
+        //     return Ok(id);
+        // }
 
         let mut doc = Document::load(path, self.theme.scopes())?;
 
@@ -73,13 +80,14 @@ impl Editor {
             .unwrap();
         }
 
-        let doc = Rc::new(RefCell::new(doc));
-        // TODO: store id as doc.id
-        let id = self.documents.insert(doc.clone());
+        let id = self.documents.insert(doc);
+        self.documents[id].id = id;
 
-        let view = View::new(doc)?;
+        let view = View::new(id)?;
         self.tree.insert(view);
-        Ok(())
+        self._refresh();
+
+        Ok(id)
     }
 
     pub fn close(&mut self, id: Key) {
@@ -88,7 +96,7 @@ impl Editor {
         let language_servers = &mut self.language_servers;
         let executor = self.executor;
 
-        let doc = view.doc.borrow();
+        let doc = &self.documents[view.doc];
 
         let language_server = doc
             .language
@@ -99,14 +107,14 @@ impl Editor {
             smol::block_on(language_server.text_document_did_close(doc.identifier())).unwrap();
         }
 
-        drop(doc); // to stop borrowing self.tree
-
         // self.documents.remove(view.doc);
         self.tree.remove(id);
+        self._refresh();
     }
 
-    pub fn resize(&mut self) {
-        self.tree.focus_next();
+    pub fn resize(&mut self, area: Rect) {
+        self.tree.resize(area);
+        self._refresh();
     }
 
     pub fn focus_next(&mut self) {
@@ -125,12 +133,26 @@ impl Editor {
         self.tree.get_mut(self.tree.focus)
     }
 
+    pub fn ensure_cursor_in_view(&mut self, id: Key) {
+        let view = self.tree.get_mut(id);
+        let doc = &self.documents[view.doc];
+        view.ensure_cursor_in_view(doc)
+    }
+
+    pub fn document(&self, id: DocumentId) -> Option<&Document> {
+        self.documents.get(id)
+    }
+
+    pub fn documents(&self) -> impl Iterator<Item = &Document> {
+        self.documents.iter().map(|(_id, doc)| doc)
+    }
+
     pub fn cursor_position(&self) -> Option<helix_core::Position> {
         const OFFSET: u16 = 7; // 1 diagnostic + 5 linenr + 1 gutter
         let view = self.view();
-        let doc = view.doc.borrow();
+        let doc = &self.documents[view.doc];
         let cursor = doc.selection().cursor();
-        if let Some(mut pos) = view.screen_coords_at_pos(doc.text().slice(..), cursor) {
+        if let Some(mut pos) = view.screen_coords_at_pos(doc, doc.text().slice(..), cursor) {
             pos.col += view.area.x as usize + OFFSET as usize;
             pos.row += view.area.y as usize;
             return Some(pos);
diff --git a/helix-view/src/tree.rs b/helix-view/src/tree.rs
index 0a487b6f..e56566e3 100644
--- a/helix-view/src/tree.rs
+++ b/helix-view/src/tree.rs
@@ -164,7 +164,18 @@ impl Tree {
         self.recalculate()
     }
 
-    pub fn views(&mut self) -> impl Iterator<Item = (&mut View, bool)> {
+    pub fn views(&self) -> impl Iterator<Item = (&View, bool)> {
+        let focus = self.focus;
+        self.nodes.iter().filter_map(move |(key, node)| match node {
+            Node {
+                content: Content::View(view),
+                ..
+            } => Some((view.as_ref(), focus == key)),
+            _ => None,
+        })
+    }
+
+    pub fn views_mut(&mut self) -> impl Iterator<Item = (&mut View, bool)> {
         let focus = self.focus;
         self.nodes
             .iter_mut()
@@ -231,7 +242,6 @@ impl Tree {
                 Content::View(view) => {
                     // debug!!("setting view area {:?}", area);
                     view.area = area;
-                    view.ensure_cursor_in_view();
                 } // TODO: call f()
                 Content::Container(container) => {
                     // debug!!("setting container area {:?}", area);
diff --git a/helix-view/src/view.rs b/helix-view/src/view.rs
index 2a77f2c0..9d3f1412 100644
--- a/helix-view/src/view.rs
+++ b/helix-view/src/view.rs
@@ -1,7 +1,6 @@
 use anyhow::Error;
 
 use std::borrow::Cow;
-use std::{cell::RefCell, rc::Rc};
 
 use crate::{Document, DocumentId};
 use helix_core::{
@@ -15,13 +14,13 @@ pub const PADDING: usize = 5;
 
 pub struct View {
     pub id: Key,
-    pub doc: Rc<RefCell<Document>>,
+    pub doc: DocumentId,
     pub first_line: usize,
     pub area: Rect,
 }
 
 impl View {
-    pub fn new(doc: Rc<RefCell<Document>>) -> Result<Self, Error> {
+    pub fn new(doc: DocumentId) -> Result<Self, Error> {
         let view = Self {
             id: Key::default(),
             doc,
@@ -32,8 +31,7 @@ impl View {
         Ok(view)
     }
 
-    pub fn ensure_cursor_in_view(&mut self) {
-        let doc = self.doc.borrow();
+    pub fn ensure_cursor_in_view(&mut self, doc: &Document) {
         let cursor = doc.selection().cursor();
         let line = doc.text().char_to_line(cursor);
         let document_end = self.first_line + (self.area.height as usize).saturating_sub(2);
@@ -51,8 +49,7 @@ impl View {
 
     /// Calculates the last visible line on screen
     #[inline]
-    pub fn last_line(&self) -> usize {
-        let doc = self.doc.borrow();
+    pub fn last_line(&self, doc: &Document) -> usize {
         let height = self.area.height.saturating_sub(1); // - 1 for statusline
         std::cmp::min(
             self.first_line + height as usize,
@@ -63,10 +60,15 @@ impl View {
     /// Translates a document position to an absolute position in the terminal.
     /// Returns a (line, col) position if the position is visible on screen.
     // TODO: Could return width as well for the character width at cursor.
-    pub fn screen_coords_at_pos(&self, text: RopeSlice, pos: usize) -> Option<Position> {
+    pub fn screen_coords_at_pos(
+        &self,
+        doc: &Document,
+        text: RopeSlice,
+        pos: usize,
+    ) -> Option<Position> {
         let line = text.char_to_line(pos);
 
-        if line < self.first_line || line > self.last_line() {
+        if line < self.first_line || line > self.last_line(doc) {
             // Line is not visible on screen
             return None;
         }
@@ -74,7 +76,7 @@ impl View {
         let line_start = text.line_to_char(line);
         let line_slice = text.slice(line_start..pos);
         let mut col = 0;
-        let tab_width = self.doc.borrow().tab_width();
+        let tab_width = doc.tab_width();
 
         for grapheme in RopeGraphemes::new(line_slice) {
             if grapheme == "\t" {