Fix `deserialize` with JSON array

Fixes #28285.

1 files changed, 10 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapters/postgresql/json_test.rb b/activerecord/test/cases/adapters/postgresql/json_test.rb
index 93558ac4d2..d4e627001c 100644
--- a/activerecord/test/cases/adapters/postgresql/json_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/json_test.rb
@@ -16,6 +16,7 @@ module PostgresqlJSONSharedTestCases
       @connection.create_table("json_data_type") do |t|
         t.public_send column_type, "payload", default: {} # t.json 'payload', default: {}
         t.public_send column_type, "settings"             # t.json 'settings'
+        t.public_send column_type, "objects", array: true # t.json 'objects', array: true
       end
     rescue ActiveRecord::StatementInvalid
       skip "do not test on PostgreSQL without #{column_type} type."
@@ -75,6 +76,15 @@ module PostgresqlJSONSharedTestCases
     assert_equal({ "string" => "foo", "symbol" => "bar" }, x.reload.payload)
   end
 
+  def test_deserialize_with_array
+    x = JsonDataType.new(objects: ["foo" => "bar"])
+    assert_equal ["foo" => "bar"], x.objects
+    x.save!
+    assert_equal ["foo" => "bar"], x.objects
+    x.reload
+    assert_equal ["foo" => "bar"], x.objects
+  end
+
   def test_type_cast_json
     type = JsonDataType.type_for_attribute("payload")