Drop support for Rails 5.0

lib/sequel/extensions/activerecord_connection.rb

@@ -194,18 +194,12 @@ def with_activerecord_connection
     # Active Record doesn't guarantee that a single connection can only be used
     # by one thread at a time, so we need to use locking, which is what Active
     # Record does internally as well.
-    if ActiveRecord.version >= Gem::Version.new("5.1")
-      def activerecord_lock
-        activerecord_connection.lock.synchronize do
-          ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
-            yield
-          end
+    def activerecord_lock
+      activerecord_connection.lock.synchronize do
+        ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+          yield
         end
       end
-    else
-      def activerecord_lock
-        yield
-      end
     end
 
     def activerecord_connection

sequel-activerecord_connection.gemspec

@@ -12,7 +12,7 @@ Gem::Specification.new do |spec|
   spec.required_ruby_version = ">= 2.5"
 
   spec.add_dependency "sequel", "~> 5.38"
-  spec.add_dependency "activerecord", ">= 5.0", "< 8.1"
+  spec.add_dependency "activerecord", ">= 5.1", "< 8.1"
 
   spec.add_development_dependency "sequel_pg" unless RUBY_ENGINE == "jruby"
   spec.add_development_dependency "minitest"

test/extension_test.rb

@@ -104,7 +104,7 @@
       q2.pop
 
       [thread1, thread2].each(&:join)
-    end unless ActiveRecord.version < Gem::Version.new("5.1") || ActiveRecord.version >= Gem::Version.new("7.2")
+    end unless ActiveRecord.version >= Gem::Version.new("7.2")
 
     it "checks the expected connection class" do
       db = Sequel.connect "sqlite://",