From 8320e4794efd0af7c86256865854f9f7232df60a Mon Sep 17 00:00:00 2001
From: Ihor Radchenko <yantar92@posteo.net>
Date: Wed, 18 Oct 2023 11:37:13 +0300
Subject: [PATCH] org-entry-get-with-inheritance: Fix inherited explicit nil
 value

* lisp/org.el (org-entry-get-with-inheritance): Do not ignore when
property has explicit "nil" value.
* testing/lisp/test-org.el (test-org/entry-get): Add test.
---
 lisp/org.el              |  5 +++--
 testing/lisp/test-org.el | 28 ++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/lisp/org.el b/lisp/org.el
index c99887723..bda64bb6c 100644
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -12958,7 +12958,8 @@ However, if LITERAL-NIL is set, return the string value \"nil\" instead."
         (org-element-at-point epom)
         (lambda (el)
           (pcase-let ((`(,val . ,val+)
-                       (org--property-local-values property literal-nil el)))
+                       ;; Force LITERAL-NIL t.
+                       (org--property-local-values property t el)))
             (if (not val)
                 ;; PROPERTY+
                 (prog1 nil ; keep looking for PROPERTY
@@ -12976,7 +12977,7 @@ However, if LITERAL-NIL is set, return the string value \"nil\" instead."
     ;; only PROPERTY+).
     (unless found-inherited?
       (when-let ((global (org--property-global-or-keyword-value
-                          property literal-nil)))
+                          property t)))
         (setq values (cons global values))))
     (when values
       (setq values (mapconcat
diff --git a/testing/lisp/test-org.el b/testing/lisp/test-org.el
index 98d3e2782..21b850c03 100644
--- a/testing/lisp/test-org.el
+++ b/testing/lisp/test-org.el
@@ -6863,6 +6863,34 @@ Paragraph<point>"
 	      "#+PROPERTY: A 0\n* H\n:PROPERTIES:\n:A+: 1\n:END:"
 	    (org-mode-restart)
 	    (org-entry-get (point-max) "A" t))))
+  ;; Explicit nil value takes precedence over parent non-nil properties.
+  (should-not
+   (org-test-with-temp-text
+       "* 1
+:PROPERTIES:
+:PROP: value
+:END:
+** 2
+:PROPERTIES:
+:PROP: nil
+:END:
+*** 3
+"
+     (org-entry-get (point-max) "PROP" t)))
+  (should
+   (equal "value"
+          (org-test-with-temp-text
+              "* 1
+:PROPERTIES:
+:PROP: value
+:END:<point>
+** 2
+:PROPERTIES:
+:PROP: nil
+:END:
+*** 3
+"
+            (org-entry-get nil "PROP" t))))
   ;; document level property-drawer has precedance over
   ;; global-property by PROPERTY-keyword.
   (should