g. goes to where the last edit ended

helix goto_last_modification: every range moves to the end of the last
change (the start of a deletion, the end of an insertion), extending in
select mode. The position is kept on the Text in surface rows, set where
setEditText hands a body its new text, so a terminal's typed text has one
too and moves with its scrollback.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/edit.zig b/src/edit.zig
index 5e0d20a4..9398674a 100644
--- a/src/edit.zig
+++ b/src/edit.zig
@@ -484,6 +484,13 @@ pub fn setEditText(p: *Pardes, t: *Text, new: []u8) void {
         return;
     }
     const pane = t.pane() orelse return retireEditText(p, new);
+    // what changed ended where the texts agree again from their ends
+    const old: []const u8, const row0: i32 = if (pane.file) |f| .{ f.content, 0 } else if (pane.ovl) |o| .{ o.text, o.row } else .{ "", 0 };
+    const front = std.mem.indexOfDiff(u8, old, new) orelse @min(old.len, new.len);
+    var back: usize = 0;
+    while (back < @min(old.len, new.len) - front and old[old.len - 1 - back] == new[new.len - 1 - back]) back += 1;
+    const end = modal.positionAt(new, new.len - back);
+    t.last_edit = .{ .row = @as(i32, @intCast(end.row)) + row0, .col = @intCast(end.col) };
     if (pane.file) |*f| return panes.File.setContent(p, f, new);
     panes.Terminal.setEditText(p, pane, new);
 }