1 files changed, 11 insertions, 0 deletions
diff --git a/activerecord/test/cases/adapters/postgresql/geometric_test.rb b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
index 2f106ee664..aa737617c4 100644
--- a/activerecord/test/cases/adapters/postgresql/geometric_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
@@ -61,4 +61,15 @@ class PostgresqlPointTest < ActiveRecord::TestCase
     assert record.reload
     assert_equal [1.1, 2.2], record.x
   end
+
+  def test_mutation
+    p = PostgresqlPoint.create! x: [10, 20]
+
+    p.x[1] = 25
+    p.save!
+    p.reload
+
+    assert_equal [10.0, 25.0], p.x
+    assert_not p.changed?
+  end
 end