From 4924822c88ddba897114c6afffd2432fa9d21fa9 Mon Sep 17 00:00:00 2001
From: Mamoru TASAKA <mtasaka@fedoraproject.org>
Date: Fri, 15 Dec 2023 15:09:57 +0900
Subject: [PATCH] change: make nil_safe_casecmp judge compatible for nil-nil
 comparison

Ruby returns 0 (not nil) for nil <=> nil, i.e. nil and nil are judged
as equal for comparison, and so returns nil_safe_compare .
ref: https://github.com/Shopify/liquid/pull/1476

To make the behavior of nil_safe_casecmp consistent with
nil_safe_compare , change nil_safe_casecmp so that comparison between
nil <=> nil return 0 (equal).

Also change testsuite to reflect this change.

Fixes #1759 .
---
 lib/liquid/standardfilters.rb            | 2 ++
 test/integration/standard_filter_test.rb | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/liquid/standardfilters.rb b/lib/liquid/standardfilters.rb
index 7a92c6753..3b0ecf15d 100644
--- a/lib/liquid/standardfilters.rb
+++ b/lib/liquid/standardfilters.rb
@@ -944,6 +944,8 @@ def nil_safe_compare(a, b)
     def nil_safe_casecmp(a, b)
       if !a.nil? && !b.nil?
         a.to_s.casecmp(b.to_s)
+      elsif a.nil? && b.nil?
+        0
       else
         a.nil? ? 1 : -1
       end
diff --git a/test/integration/standard_filter_test.rb b/test/integration/standard_filter_test.rb
index 28c006cb9..0564404c3 100644
--- a/test/integration/standard_filter_test.rb
+++ b/test/integration/standard_filter_test.rb
@@ -331,8 +331,8 @@ def test_sort_natural_when_property_is_sometimes_missing_puts_nils_last
       { "price" => "1", "handle" => "gamma" },
       { "price" => 2, "handle" => "epsilon" },
       { "price" => "4", "handle" => "alpha" },
-      { "handle" => "delta" },
       { "handle" => "beta" },
+      { "handle" => "delta" },
     ]
     assert_equal(expectation, @filters.sort_natural(input, "price"))
   end