Implement view transpose (#2461)

Change the layout of existing split view from horizontal to vertical and
vica-versa. It only effects the focused view and its siblings, i.e. not
recursive.

Command is mapped to 't' or 'C-t' under the Window menus.

2 files changed, 16 insertions, 0 deletions

diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index f4a48ba6..1ad21059 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -885,6 +885,10 @@ impl Editor {
         self.tree.focus_direction(tree::Direction::Down);
     }
 
+    pub fn transpose_view(&mut self) {
+        self.tree.transpose();
+    }
+
     pub fn should_close(&self) -> bool {
         self.tree.is_empty()
     }
diff --git a/helix-view/src/tree.rs b/helix-view/src/tree.rs
index b068f4c7..522a79d7 100644
--- a/helix-view/src/tree.rs
+++ b/helix-view/src/tree.rs
@@ -526,6 +526,18 @@ impl Tree {
         }
     }
 
+    pub fn transpose(&mut self) {
+        let focus = self.focus;
+        let parent = self.nodes[focus].parent;
+        if let Content::Container(container) = &mut self.nodes[parent].content {
+            container.layout = match container.layout {
+                Layout::Vertical => Layout::Horizontal,
+                Layout::Horizontal => Layout::Vertical,
+            };
+            self.recalculate();
+        }
+    }
+
     pub fn area(&self) -> Rect {
         self.area
     }