From 04e8f42452c9f7fd5a9c9f76b34f51c7cb78673a Mon Sep 17 00:00:00 2001
From: Josh Moller-Mara <jmm@cns.nyu.edu>
Date: Sun, 22 Dec 2019 05:35:14 +0800
Subject: [PATCH] Fix org-ql--value-at returning org-ql-nil during cache miss

"org-ql--value-at" improperly returned "org-ql-nil" when "fn" returns
nil during a cache miss. All following calls to "org-ql--value-at",
however, would properly return "nil".
---
 org-ql.el | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/org-ql.el b/org-ql.el
index 1f39d3f..b253fee 100644
--- a/org-ql.el
+++ b/org-ql.el
@@ -477,7 +477,9 @@ Values compared with `equal'."
                  org-ql-node-value-cache))
       (map-put value-cache fn new-value)
       (puthash position value-cache position-cache)
-      new-value)))
+      (pcase new-value
+        ('org-ql-nil nil)
+        (_ new-value)))))
 
 (defun org-ql--add-markers (element)
   "Return ELEMENT with Org marker text properties added.