diff --git a/helix-view/src/tree.rs b/helix-view/src/tree.rs index 4c9eba0fd1256..b7ad5aa9de05e 100644 --- a/helix-view/src/tree.rs +++ b/helix-view/src/tree.rs @@ -214,33 +214,56 @@ impl Tree { node } - pub fn remove(&mut self, index: ViewId) { - let mut stack = Vec::new(); + /// Get a mutable reference to a [Container] by index. + /// # Panics + /// Panics if `index` is not in self.nodes, or if the node's content is not a [Content::Container]. + fn container_mut(&mut self, index: ViewId) -> &mut Container { + match &mut self.nodes[index] { + Node { + content: Content::Container(container), + .. + } => container, + _ => unreachable!(), + } + } + + fn remove_or_replace(&mut self, child: ViewId, replacement: Option) { + let parent = self.nodes[child].parent; + + self.nodes.remove(child); + let container = self.container_mut(parent); + let pos = container + .children + .iter() + .position(|&item| item == child) + .unwrap(); + + if let Some(new) = replacement { + container.children[pos] = new; + self.nodes[new].parent = parent; + } else { + container.children.remove(pos); + } + } + + pub fn remove(&mut self, index: ViewId) { if self.focus == index { // focus on something else self.focus = self.prev(); } - stack.push(index); + let parent = self.nodes[index].parent; + let parent_is_root = parent == self.root; - while let Some(index) = stack.pop() { - let parent_id = self.nodes[index].parent; - if let Node { - content: Content::Container(container), - .. - } = &mut self.nodes[parent_id] - { - if let Some(pos) = container.children.iter().position(|&child| child == index) { - container.children.remove(pos); - // TODO: if container now only has one child, remove it and place child in parent - if container.children.is_empty() && parent_id != self.root { - // if container now empty, remove it - stack.push(parent_id); - } - } - } - self.nodes.remove(index); + self.remove_or_replace(index, None); + + let parent_container = self.container_mut(parent); + if parent_container.children.len() == 1 && !parent_is_root { + // Lets merge the only child back to its grandparent so that Views + // are equally spaced. + let sibling = parent_container.children.pop().unwrap(); + self.remove_or_replace(parent, Some(sibling)); } self.recalculate() @@ -873,4 +896,42 @@ mod test { assert_eq!(doc_id(&tree, l2), Some(doc_r0)); assert_eq!(doc_id(&tree, r0), Some(doc_l0)); } + + #[test] + fn all_vertical_views_have_same_width() { + let tree_area_width = 180; + let mut tree = Tree::new(Rect { + x: 0, + y: 0, + width: tree_area_width, + height: 80, + }); + let mut view = View::new(DocumentId::default(), GutterConfig::default()); + view.area = Rect::new(0, 0, 180, 80); + tree.insert(view); + + let view = View::new(DocumentId::default(), GutterConfig::default()); + tree.split(view, Layout::Vertical); + + let view = View::new(DocumentId::default(), GutterConfig::default()); + tree.split(view, Layout::Horizontal); + + tree.remove(tree.focus); + + let view = View::new(DocumentId::default(), GutterConfig::default()); + tree.split(view, Layout::Vertical); + + // Make sure that we only have one level in the tree. + assert_eq!(3, tree.views().count()); + assert_eq!( + vec![ + tree_area_width / 3, + tree_area_width / 3, + tree_area_width / 3 - 2 // Rounding in `recalculate`. + ], + tree.views() + .map(|(view, _)| view.area.width) + .collect::>() + ); + } }