2 files changed, 51 insertions, 0 deletions
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index ad155c7492..d1d4d545a3 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -504,6 +504,39 @@ module ActiveRecord
         assert_deprecated { @conn.valid_alter_table_type?(:string) }
       end
 
+      def test_db_is_not_readonly_when_readonly_option_is_false
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3",
+                                       readonly: false
+
+        assert_not_predicate conn.raw_connection, :readonly?
+      end
+
+      def test_db_is_not_readonly_when_readonly_option_is_unspecified
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3"
+
+        assert_not_predicate conn.raw_connection, :readonly?
+      end
+
+      def test_db_is_readonly_when_readonly_option_is_true
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3",
+                                       readonly: true
+
+        assert_predicate conn.raw_connection, :readonly?
+      end
+
+      def test_writes_are_not_permitted_to_readonly_databases
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3",
+                                       readonly: true
+
+        assert_raises(ActiveRecord::StatementInvalid, /SQLite3::ReadOnlyException/) do
+          conn.execute("CREATE TABLE test(id integer)")
+        end
+      end
+
       private
 
         def assert_logged(logs)
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 8be663e3dc..5b8d4722af 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -123,6 +123,24 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal memberships(:membership_of_boring_club), member.current_membership
   end
 
+  def test_loading_associations_dont_leak_instance_state
+    assertions = ->(firm) {
+      assert_equal companies(:first_firm), firm
+
+      assert_predicate firm.association(:readonly_account), :loaded?
+      assert_predicate firm.association(:accounts), :loaded?
+
+      assert_equal accounts(:signals37), firm.readonly_account
+      assert_equal [accounts(:signals37)], firm.accounts
+
+      assert_predicate firm.readonly_account, :readonly?
+      assert firm.accounts.none?(&:readonly?)
+    }
+
+    assertions.call(Firm.preload(:readonly_account, :accounts).first)
+    assertions.call(Firm.eager_load(:readonly_account, :accounts).first)
+  end
+
   def test_with_ordering
     list = Post.all.merge!(includes: :comments, order: "posts.id DESC").to_a
     [:other_by_mary, :other_by_bob, :misc_by_mary, :misc_by_bob, :eager_other,