test, `Generators::GeneratedAttribute` with references, required, index.

Closes #17197.
Closes #17207.

`{required}` is a type modifier so it should be:

    user:references{required}:index

and not:

    user:references:index{required}

1 files changed, 8 insertions, 0 deletions

diff --git a/railties/test/generators/generated_attribute_test.rb b/railties/test/generators/generated_attribute_test.rb
index c48bc20899..ee7c009305 100644
--- a/railties/test/generators/generated_attribute_test.rb
+++ b/railties/test/generators/generated_attribute_test.rb
@@ -141,4 +141,12 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
     assert_equal "post_id", create_generated_attribute('references', 'post').column_name
     assert_equal "post_id", create_generated_attribute('belongs_to', 'post').column_name
   end
+
+  def test_parse_required_attribute_with_index
+    att = Rails::Generators::GeneratedAttribute.parse("supplier:references{required}:index")
+    assert_equal "supplier", att.name
+    assert_equal :references, att.type
+    assert att.has_index?
+    assert att.required?
+  end
 end