From 38ef079099400684eebaf59294a97fa4e697b9ea Mon Sep 17 00:00:00 2001
From: wongjiahau <hou32hou@gmail.com>
Date: Sat, 25 Feb 2023 13:12:56 +0800
Subject: [PATCH] feat(tree): jump forward

---
 changes                   |  4 +--
 helix-term/src/ui/tree.rs | 60 +++++++++++++++++++++++++++++++++++----
 2 files changed, 57 insertions(+), 7 deletions(-)

diff --git a/changes b/changes
index cb1b3eeb..326a0df6 100644
--- a/changes
+++ b/changes
@@ -31,8 +31,8 @@ TODO
 New:
 - [x] increase indentation
 - [x] Change '[' to "go to previous root"
-- [x] Change 'b' to "go to parent"
-- [x] Use C-o for jumping to previous position
+- [x] Change 'B' to "go to parent"
+- [x] Use C-o/C-i for jump backward/forward
 - [x] on focus indication
 - [x] support creating files and folder and the same time (`mkdir -p`)
 - [x] Ctrl-o should work for 'h', 'gg', 'ge', etc
diff --git a/helix-term/src/ui/tree.rs b/helix-term/src/ui/tree.rs
index 8e8ae1f4..25f322a4 100644
--- a/helix-term/src/ui/tree.rs
+++ b/helix-term/src/ui/tree.rs
@@ -289,7 +289,8 @@ pub struct TreeView<T: TreeViewItem> {
     /// Selected item idex
     selected: usize,
 
-    history: Vec<usize>,
+    backward_jumps: Vec<usize>,
+    forward_jumps: Vec<usize>,
 
     saved_view: Option<SavedView>,
 
@@ -322,7 +323,8 @@ impl<T: TreeViewItem> TreeView<T> {
         Self {
             tree: Tree::new(root, items),
             selected: 0,
-            history: vec![],
+            backward_jumps: vec![],
+            forward_jumps: vec![],
             saved_view: None,
             winline: 0,
             column: 0,
@@ -506,6 +508,7 @@ pub fn tree_view_help() -> Vec<(&'static str, &'static str)> {
         ("Home", "Scroll to the leftmost"),
         ("End", "Scroll to the rightmost"),
         ("C-o", "Jump backward"),
+        ("C-i, Tab", "Jump forward"),
         ("C-d", "Half page down"),
         ("C-u", "Half page up"),
         ("PageUp", "Full page up"),
@@ -602,7 +605,7 @@ impl<T: TreeViewItem> TreeView<T> {
         let previous_selected = self.selected;
         self.set_selected_without_history(selected);
         if previous_selected.abs_diff(selected) > 1 {
-            self.history.push(previous_selected)
+            self.backward_jumps.push(previous_selected)
         }
     }
 
@@ -625,11 +628,18 @@ impl<T: TreeViewItem> TreeView<T> {
     }
 
     fn jump_backward(&mut self) {
-        if let Some(index) = self.history.pop() {
+        if let Some(index) = self.backward_jumps.pop() {
+            self.forward_jumps.push(self.selected);
             self.set_selected_without_history(index);
         }
     }
 
+    fn jump_forward(&mut self) {
+        if let Some(index) = self.forward_jumps.pop() {
+            self.set_selected(index)
+        }
+    }
+
     pub fn move_up(&mut self, rows: usize) {
         self.set_selected(self.selected.saturating_sub(rows))
     }
@@ -1062,6 +1072,7 @@ impl<T: TreeViewItem + Clone> TreeView<T> {
                 key!(Home) => self.move_leftmost(),
                 key!(End) => self.move_rightmost(),
                 ctrl!('o') => self.jump_backward(),
+                ctrl!('i') | key!(Tab) => self.jump_forward(),
                 _ => return Ok(EventResult::Ignored(None)),
             };
             Ok(EventResult::Consumed(None))
@@ -2002,7 +2013,7 @@ krabby_patty
     }
 
     #[test]
-    fn test_jump_backward() {
+    fn test_jump_backward_forward() {
         let mut view = dummy_tree_view();
         view.move_down_half_page();
         render(&mut view);
@@ -2041,6 +2052,45 @@ krabby_patty
  gary_the_snail
  karen
  king_neptune
+ krabby_patty
+          "
+            .trim()
+        );
+
+        view.jump_forward();
+        assert_eq!(
+            render(&mut view),
+            "
+[who_lives_in_a_pineapple_under_the_sea]
+ gary_the_snail
+ (karen)
+ king_neptune
+ krabby_patty
+          "
+            .trim()
+        );
+
+        view.jump_forward();
+        assert_eq!(
+            render(&mut view),
+            "
+[who_lives_in_a_pineapple_under_the_sea]
+ gary_the_snail
+ karen
+ king_neptune
+ (krabby_patty)
+          "
+            .trim()
+        );
+
+        view.jump_backward();
+        assert_eq!(
+            render(&mut view),
+            "
+[who_lives_in_a_pineapple_under_the_sea]
+ gary_the_snail
+ (karen)
+ king_neptune
  krabby_patty
           "
             .trim()