diff --git a/rubygem-activerecord-5.2.3-Update-for-Time-inspect.patch b/rubygem-activerecord-5.2.3-Update-for-Time-inspect.patch
new file mode 100644
index 0000000..675676c
--- /dev/null
+++ b/rubygem-activerecord-5.2.3-Update-for-Time-inspect.patch
@@ -0,0 +1,24 @@
+From dbb9833ef7f133afa7d2872ec4554245a7572141 Mon Sep 17 00:00:00 2001
+From: Nobuyoshi Nakada <nobu@ruby-lang.org>
+Date: Sat, 21 Sep 2019 16:57:24 +0900
+Subject: [PATCH] Update for `Time#inspect`
+
+Since ruby/ruby@5208c431be, `Time#inspect` is separated from
+`Time#to_s`, and the former may contain the fraction part now.
+---
+ activerecord/test/cases/core_test.rb | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/activerecord/test/cases/core_test.rb b/activerecord/test/cases/core_test.rb
+index 36e3d543cd34..de6f4d28aa03 100644
+--- a/activerecord/test/cases/core_test.rb
++++ b/activerecord/test/cases/core_test.rb
+@@ -74,7 +74,7 @@ def test_pretty_print_persisted
+      title: "The First Topic",
+      author_name: "David",
+      author_email_address: "david@loudthinking.com",
+-     written_on: 2003-07-16 14:28:11 UTC,
++     written_on: 2003-07-16 14:28:11(?:\.2233)? UTC,
+      bonus_time: 2000-01-01 14:28:00 UTC,
+      last_read: Thu, 15 Apr 2004,
+      content: "Have a nice day",
diff --git a/rubygem-activerecord.spec b/rubygem-activerecord.spec
index b1acae4..1129432 100644
--- a/rubygem-activerecord.spec
+++ b/rubygem-activerecord.spec
@@ -4,7 +4,7 @@
 Name: rubygem-%{gem_name}
 Epoch: 1
 Version: 5.2.3
-Release: 3%{?dist}
+Release: 4%{?dist}
 Summary: Object-relational mapper framework (part of Rails)
 License: MIT
 URL: http://rubyonrails.org
@@ -13,6 +13,9 @@ Source0: https://rubygems.org/gems/%{gem_name}-%{version}.gem
 # cd rails/activerecord/
 # git checkout v5.2.3 && tar czvf activerecord-5.2.3-tests.tgz test/
 Source1: activerecord-%{version}-tests.tgz
+# Fix Ruby 2.7 compatibility.
+# https://github.com/rails/rails/pull/37262
+Patch0: rubygem-activerecord-5.2.3-Update-for-Time-inspect.patch
 
 # Database dump/load reuires the executable.
 Suggests: %{_bindir}/sqlite3
@@ -43,7 +46,11 @@ BuildArch: noarch
 Documentation for %{name}.
 
 %prep
-%setup -q -n %{gem_name}-%{version}
+%setup -q -n %{gem_name}-%{version} -b 1
+
+pushd %{_builddir}
+%patch0 -p2
+popd
 
 %build
 gem build ../%{gem_name}-%{version}.gemspec
@@ -58,9 +65,8 @@ cp -a .%{gem_dir}/* \
 %check
 pushd .%{gem_instdir}
 
-tar xzvf %{SOURCE1}
-
-cat %{PATCH1} | patch -p2 -F 0
+# Move the tests into place.
+cp -a %{_builddir}/test test
 
 # Tests are broken on Fedora
 # https://github.com/rails/rails/pull/34436
@@ -98,6 +104,10 @@ popd
 %{gem_instdir}/examples
 
 %changelog
+* Fri Apr 17 2020 Vít Ondruch <vondruch@redhat.com> - 1:5.2.3-4
+- Fix Ruby 2.7 test errors.
+  Resovles: rhbz#1799986
+
 * Thu Jan 30 2020 Fedora Release Engineering <releng@fedoraproject.org> - 1:5.2.3-3
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_32_Mass_Rebuild