From 661c233ce1b40863c6433b4e07c3a6eefeff9181 Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Wed, 19 Feb 2020 23:36:14 +0000
Subject: [PATCH] [client] Fix cursor becoming invisible

---
 src/Forest/Client/NodeUtil.hs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/Forest/Client/NodeUtil.hs b/src/Forest/Client/NodeUtil.hs
index 2ccb332..1f0c031 100644
--- a/src/Forest/Client/NodeUtil.hs
+++ b/src/Forest/Client/NodeUtil.hs
@@ -33,7 +33,13 @@ foldVisibleNodes = foldVisibleNodes' mempty
 
 -- | Keep only those nodes that are visible according to the 'Unfolded' set.
 applyFolds :: Unfolded -> Node -> Node
-applyFolds = foldVisibleNodes (\_ node _ -> node)
+applyFolds unfolded node
+  | mempty `Set.member` unfolded = node {nodeChildren = children}
+  | otherwise = node {nodeChildren = OMap.empty}
+  where
+    children =
+      OMap.mapWithKey (\nid -> applyFolds $ narrowSet nid unfolded) $
+      nodeChildren node
 
 -- | Return the 'Path's to a node and its subnodes in the order they would be
 -- displayed in.