test, reset changed state in PG's uuid tests.

This resulted in some unrelated errors on Traivs:

  1) Error:
PostgresqlUUIDTest#test_treat_blank_uuid_as_nil:
ActiveRecord::StatementInvalid: PG::UndefinedColumn: ERROR:  column "thingy" of relation "uuid_data_type" does not exist
LINE 1: INSERT INTO "uuid_data_type" ("thingy") VALUES ($1) RETURNIN...
                                      ^
: INSERT INTO "uuid_data_type" ("thingy") VALUES ($1) RETURNING "id"

/cc @zuhao

1 files changed, 4 insertions, 2 deletions

diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index bdf8e15e3e..ffce7c0d5f 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -45,12 +45,14 @@ class PostgresqlUUIDTest < ActiveRecord::TestCase
     UUIDType.reset_column_information
     column = UUIDType.columns.find { |c| c.name == 'thingy' }
     assert_equal "uuid_generate_v1()", column.default_function
-    
+
     @connection.change_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v4()"
-    
+
     UUIDType.reset_column_information
     column = UUIDType.columns.find { |c| c.name == 'thingy' }
     assert_equal "uuid_generate_v4()", column.default_function
+  ensure
+    UUIDType.reset_column_information
   end
 
   def test_data_type_of_uuid_types