Implement splitting vertically with syncing

helix-term/src/commands.rs

@@ -470,6 +470,7 @@ impl MappableCommand {
         hsplit, "Horizontal bottom split",
         hsplit_new, "Horizontal bottom split scratch buffer",
         vsplit, "Vertical right split",
+        vsplit_extend, "Vertical right extend split scratch buffer",
         vsplit_new, "Vertical right split scratch buffer",
         wclose, "Close window",
         wonly, "Close windows except current",
@@ -648,6 +649,79 @@ fn move_impl(cx: &mut Context, move_fn: MoveFn, dir: Direction, behaviour: Movem
     });
     drop(annotations);
     doc.set_selection(view.id, selection);
+    moved_synced(cx);
+}
+
+pub fn moved_synced(cx: &mut Context) {
+    let view = view!(cx.editor);
+    let focused_id = view.id;
+
+    let view_id = view.id;
+
+    let doc = doc!(cx.editor);
+    let focus_last_line = view.estimate_last_doc_line(doc);
+    //let focus_last_line = view.last_visual_line(doc);
+    let focus_inner_height = view.inner_height();
+
+    let doc = doc_mut!(cx.editor);
+
+    let syncs = cx.editor.tree.get_synced_views(view_id);
+
+    let synced_views: Vec<ViewId> = syncs
+        .iter()
+        .find(|x| x.document_id == doc.id())
+        .map(|x| x.views.clone())
+        .unwrap_or(Vec::new());
+
+    if synced_views.is_empty() {
+        return;
+    }
+
+    let synced_views: Vec<(usize, ViewId)> = synced_views.into_iter().enumerate().collect();
+
+    let focus_ord_num = synced_views.iter().find(|(_, x)| *x == focused_id);
+
+    let focus_ord_num = match focus_ord_num {
+        Some(n) => n.0,
+        None => return,
+    };
+
+    for (view, focus) in cx.editor.tree.views_mut() {
+        let sync_find = synced_views.iter().find(|(_, x)| *x == view.id);
+        let is_synced = sync_find.is_some();
+
+        if focus {}
+        if focus || !is_synced {
+            continue;
+        }
+
+        // Just checked if is some above
+        let (current_order_id, _) = sync_find.unwrap();
+
+        // if focus is prior view then it is synced above
+        let offset = if *current_order_id < focus_ord_num {
+            focus_last_line as isize
+        } else {
+            let focus_first_line: usize =
+                0.max(focus_last_line as isize - focus_inner_height as isize) as usize;
+
+            0.max(focus_first_line as isize - view.inner_height() as isize) as isize
+        };
+
+        let text_fmt = doc.text_format(view.inner_area(doc).width, None);
+        let annotations = view.text_annotations(doc, None);
+
+        let doc_text = doc.text().slice(..);
+
+        (view.offset.anchor, view.offset.vertical_offset) = char_idx_at_visual_offset(
+            doc_text,
+            0,
+            view.offset.vertical_offset as isize + offset as isize,
+            0,
+            &text_fmt,
+            &annotations,
+        );
+    }
 }
 
 use helix_core::movement::{move_horizontally, move_vertically};
@@ -1718,6 +1792,8 @@ pub fn scroll(cx: &mut Context, offset: usize, direction: Direction, sync_cursor
             )
         });
         doc.set_selection(view.id, selection);
+
+        moved_synced(cx);
         return;
     }
 
@@ -1767,6 +1843,8 @@ pub fn scroll(cx: &mut Context, offset: usize, direction: Direction, sync_cursor
     sel = sel.replace(idx, prim_sel);
     drop(annotations);
     doc.set_selection(view.id, sel);
+
+    moved_synced(cx);
 }
 
 fn page_up(cx: &mut Context) {
@@ -1809,6 +1887,7 @@ fn page_cursor_half_up(cx: &mut Context) {
     let view = view!(cx.editor);
     let offset = view.inner_height() / 2;
     scroll(cx, offset, Direction::Backward, true);
+    moved_synced(cx);
 }
 
 fn page_cursor_half_down(cx: &mut Context) {
@@ -5160,6 +5239,17 @@ fn vsplit(cx: &mut Context) {
     split(cx.editor, Action::VerticalSplit);
 }
 
+fn vsplit_extend(cx: &mut Context) {
+    let doc = doc!(cx.editor);
+    let id = doc.id();
+
+    cx.editor.switch(id, Action::VerticalSplit);
+
+    if let Some(doc) = cx.editor.document_mut(id) {
+        doc.mark_as_focused();
+    }
+}
+
 fn vsplit_new(cx: &mut Context) {
     cx.editor.new_file(Action::VerticalSplit);
 }
@@ -5219,16 +5309,19 @@ fn insert_register(cx: &mut Context) {
 fn align_view_top(cx: &mut Context) {
     let (view, doc) = current!(cx.editor);
     align_view(doc, view, Align::Top);
+    moved_synced(cx);
 }
 
 fn align_view_center(cx: &mut Context) {
     let (view, doc) = current!(cx.editor);
     align_view(doc, view, Align::Center);
+    moved_synced(cx);
 }
 
 fn align_view_bottom(cx: &mut Context) {
     let (view, doc) = current!(cx.editor);
     align_view(doc, view, Align::Bottom);
+    moved_synced(cx);
 }
 
 fn align_view_middle(cx: &mut Context) {
@@ -5252,10 +5345,12 @@ fn align_view_middle(cx: &mut Context) {
 
 fn scroll_up(cx: &mut Context) {
     scroll(cx, cx.count(), Direction::Backward, false);
+    moved_synced(cx);
 }
 
 fn scroll_down(cx: &mut Context) {
     scroll(cx, cx.count(), Direction::Forward, false);
+    moved_synced(cx);
 }
 
 fn goto_ts_object_impl(cx: &mut Context, object: &'static str, direction: Direction) {

helix-term/src/commands/typed.rs

@@ -1668,6 +1668,41 @@ fn vsplit_new(
     Ok(())
 }
 
+fn vsplit_extend(
+    cx: &mut compositor::Context,
+    _args: &[Cow<str>],
+    event: PromptEvent,
+) -> anyhow::Result<()> {
+    if event != PromptEvent::Validate {
+        return Ok(());
+    }
+
+    let (view, doc) = current!(cx.editor);
+    let view_id = view.id;
+    let id = doc.id();
+
+    if cx
+        .editor
+        .tree
+        .get_synced_views(view_id)
+        .iter()
+        .find(|v| v.document_id == doc.id())
+        .is_some()
+    {
+        // Only support one split, possible to support more in future
+        // estimate only changes needed is the scrolling sync logic
+        cx.editor
+            .set_error(format!("Only one split per document supported"));
+        bail!("Only one split per document supported")
+    }
+
+    cx.editor.switch(id, Action::VerticalSplitSync);
+
+    cx.editor.focus_direction(tree::Direction::Left);
+
+    Ok(())
+}
+
 fn hsplit_new(
     cx: &mut compositor::Context,
     _args: &[Cow<str>],
@@ -2913,6 +2948,13 @@ pub const TYPABLE_COMMAND_LIST: &[TypableCommand] = &[
         fun: vsplit,
         signature: CommandSignature::all(completers::filename)
     },
+    TypableCommand {
+        name: "vsplit-extend",
+        aliases: &["vext"],
+        doc: "Open the file in a vertical split with scroll syncing",
+        fun: vsplit_extend,
+        signature: CommandSignature::all(completers::filename),
+    },
     TypableCommand {
         name: "vsplit-new",
         aliases: &["vnew"],

helix-view/src/editor.rs

@@ -1117,6 +1117,7 @@ pub enum Action {
     Replace,
     HorizontalSplit,
     VerticalSplit,
+    VerticalSplitSync,
 }
 
 impl Action {
@@ -1591,6 +1592,7 @@ impl Editor {
                         }
                     }
                 }
+                self.tree.remove_sync_view(view_id);
 
                 self.replace_document_in_view(view_id, id);
 
@@ -1624,6 +1626,20 @@ impl Editor {
                 doc.ensure_view_init(view_id);
                 doc.mark_as_focused();
             }
+            Action::VerticalSplitSync => {
+                // copy the current view, unless there is no view yet
+                let view = self
+                    .tree
+                    .try_get(self.tree.focus)
+                    .filter(|v| id == v.doc) // Different Document
+                    .cloned()
+                    .unwrap_or_else(|| View::new(id, self.config().gutters.clone()));
+                let view_id = self.tree.split_extend(view);
+                // initialize selection for view
+                let doc = doc_mut!(self, &id);
+                doc.ensure_view_init(view_id);
+                //doc.mark_as_focused();
+            }
         }
 
         self._refresh();

helix-view/src/tree.rs

@@ -1,4 +1,4 @@
-use crate::{graphics::Rect, View, ViewId};
+use crate::{graphics::Rect, DocumentId, View, ViewId};
 use slotmap::HopSlotMap;
 
 // the dimensions are recomputed on window resize/tree change.
@@ -60,11 +60,18 @@ pub enum Direction {
     Right,
 }
 
+#[derive(Clone, Debug)]
+pub struct SyncedViews {
+    pub views: Vec<ViewId>,
+    pub document_id: crate::DocumentId, // Could change to side by side two similar files as a diff maybe
+}
+
 #[derive(Debug)]
 pub struct Container {
     layout: Layout,
     children: Vec<ViewId>,
     area: Rect,
+    synced_views: Vec<SyncedViews>,
 }
 
 impl Container {
@@ -73,8 +80,40 @@ impl Container {
             layout,
             children: Vec::new(),
             area: Rect::default(),
+            synced_views: Vec::new(),
+        }
+    }
+
+    //Add views to sync should be at least two views to sync per document
+    fn add_sync_views(&mut self, views: Vec<ViewId>, document_id: DocumentId) {
+        match self
+            .synced_views
+            .iter_mut()
+            .find(|synced| synced.document_id == document_id)
+        {
+            Some(sync_view) => sync_view.views.extend(views),
+            None => {
+                if views.len() > 1 {
+                    self.synced_views.push(SyncedViews { views, document_id })
+                } else {
+                    panic!(
+                        "Trying to sync a less then 1 view this should not happen {}",
+                        views.len()
+                    )
+                }
+            }
         }
     }
+
+    fn remove_sync_view(&mut self, view: ViewId) {
+        // remove all view ids from sync list and
+        // remove remove any synchronisation if
+        // there is only one view
+        self.synced_views.retain_mut(|syncs| {
+            syncs.views.retain_mut(|v_id| *v_id != view);
+            syncs.views.len() > 2
+        });
+    }
 }
 
 impl Default for Container {
@@ -175,6 +214,90 @@ impl Tree {
             split.parent = parent;
             let split = self.nodes.insert(split);
 
+            let split_container = match &mut self.nodes[split] {
+                Node {
+                    content: Content::Container(container),
+                    ..
+                } => container,
+                _ => unreachable!(),
+            };
+            split_container.children.push(focus);
+            split_container.children.push(node);
+
+            self.nodes[focus].parent = split;
+            self.nodes[node].parent = split;
+
+            let container = match &mut self.nodes[parent] {
+                Node {
+                    content: Content::Container(container),
+                    ..
+                } => container,
+                _ => unreachable!(),
+            };
+
+            let pos = container
+                .children
+                .iter()
+                .position(|&child| child == focus)
+                .unwrap();
+
+            // replace focus on parent with split
+            container.children[pos] = split;
+            self.swap_sync_views(split, parent);
+        }
+
+        // focus the new node
+        self.focus = node;
+
+        // recalculate all the sizes
+        self.recalculate();
+
+        node
+    }
+
+    pub fn split_extend(&mut self, view: View) -> ViewId {
+        let doc_id = view.doc;
+        let view_id = view.id;
+        let focus = self.focus;
+        let parent = self.nodes[focus].parent;
+
+        let node = Node::view(view);
+
+        let node = self.nodes.insert(node);
+        self.get_mut(node).id = node;
+
+        let node_id = node;
+
+        let container = match &mut self.nodes[parent] {
+            Node {
+                content: Content::Container(container),
+                ..
+            } => container,
+            _ => unreachable!(),
+        };
+        if container.layout == Layout::Vertical {
+            // insert node after the current item if there is children already
+            let pos = if container.children.is_empty() {
+                0
+            } else {
+                let pos = container
+                    .children
+                    .iter()
+                    .position(|&child| child == focus)
+                    .unwrap();
+                pos + 1
+            };
+
+            container.children.insert(pos, node);
+
+            container.add_sync_views(vec![node_id, view_id], doc_id);
+
+            self.nodes[node].parent = parent;
+        } else {
+            let mut split = Node::container(Layout::Vertical);
+            split.parent = parent;
+            let split = self.nodes.insert(split);
+
             let container = match &mut self.nodes[split] {
                 Node {
                     content: Content::Container(container),
@@ -203,10 +326,19 @@ impl Tree {
 
             // replace focus on parent with split
             container.children[pos] = split;
+
+            let container = match &mut self.nodes[split] {
+                Node {
+                    content: Content::Container(c),
+                    ..
+                } => c,
+                _ => unreachable!(),
+            };
+
+            container.add_sync_views(vec![node_id, view_id], doc_id);
         }
 
-        // focus the new node
+        for (i, n) in self.nodes.iter().enumerate() {}
-        self.focus = node;
 
         // recalculate all the sizes
         self.recalculate();
@@ -253,6 +385,8 @@ impl Tree {
             self.focus = self.prev();
         }
 
+        self.remove_sync_view(index);
+
         let parent = self.nodes[index].parent;
         let parent_is_root = parent == self.root;
 
@@ -269,6 +403,41 @@ impl Tree {
         self.recalculate()
     }
 
+    pub fn remove_sync_view(&mut self, index: ViewId) {
+        let parent = self.nodes[index].parent;
+        let container = &mut self.nodes[parent].content;
+        let container = match container {
+            Content::Container(c) => c,
+            Content::View(_) => return,
+        };
+
+        container.remove_sync_view(index);
+    }
+
+    pub fn get_synced_views(&self, view_id: ViewId) -> &[SyncedViews] {
+        let parent = self.nodes[view_id].parent;
+        let container = match &self.nodes[parent] {
+            Node {
+                content: Content::Container(container),
+                ..
+            } => container,
+            _ => unreachable!(),
+        };
+        container.synced_views.as_slice()
+    }
+
+    fn swap_sync_views(&mut self, x: ViewId, y: ViewId) {
+        // These clones are needed to satisfy the borrow checker ideally it would
+        // simply be a straight call to memswap
+        let mut sync_views_x = self.container_mut(x).synced_views.clone();
+        let mut sync_views_y = self.container_mut(y).synced_views.clone();
+
+        std::mem::swap(&mut sync_views_x, &mut sync_views_y);
+
+        self.container_mut(x).synced_views = sync_views_x;
+        self.container_mut(y).synced_views = sync_views_y;
+    }
+
     pub fn views(&self) -> impl Iterator<Item = (&View, bool)> {
         let focus = self.focus;
         self.nodes.iter().filter_map(move |(key, node)| match node {
@@ -966,4 +1135,53 @@ mod test {
                 .collect::<Vec<_>>()
         );
     }
+    #[test]
+    fn split_sync_views() {
+        let mut tree = Tree::new(Rect {
+            x: 0,
+            y: 0,
+            width: 180,
+            height: 80,
+        });
+
+        let doc_main = DocumentId::default();
+        let mut view = View::new(doc_main, GutterConfig::default());
+        view.area = Rect::new(0, 0, 180, 80);
+        tree.insert(view);
+
+        let l0 = tree.focus;
+
+        let view = View::new(doc_main, GutterConfig::default());
+        tree.split_extend(view);
+        let r0 = tree.focus;
+
+        tree.focus = l0;
+
+        // Views in test
+        // | LO | R1 |
+
+        // Docs in test
+        // | doc_main | doc_main
+
+        // created a synced split
+        assert_eq!(tree.get_synced_views(view.id).len(), 1);
+
+        // Synced on the document we created
+        assert!(tree
+            .get_synced_views(view.id)
+            .iter()
+            .find(|x| x.document_id == doc_main)
+            .is_some());
+
+        // the view is on the sync list
+        assert!(tree
+            .get_synced_views(view.id)
+            .iter()
+            .find(|x| x.views.iter().find(|v| **v == view.id).is_some())
+            .is_some());
+
+        tree.remove_sync_view(view.id);
+
+        assert!(tree.get_synced_views(view.id).is_empty());
+    }
 }