Allow `column_exists?` to be passed `type` argument as a string

Currently `conn.column_exists?("testings", "created_at", "datetime")`
returns false even if the table has the `created_at` column.

That reason is that `column.type` is a symbol but passed `type` is not
normalized to symbol unlike `column_name`, it is surprising behavior to
me.

I've improved that to normalize a value before comparison.

2 files changed, 5 insertions, 10 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index 208c8c9c64..90a130320b 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -134,7 +134,7 @@ module ActiveRecord
         column_name = column_name.to_s
         checks = []
         checks << lambda { |c| c.name == column_name }
-        checks << lambda { |c| c.type == type } if type
+        checks << lambda { |c| c.type == type.to_sym rescue nil } if type
         column_options_keys.each do |attr|
           checks << lambda { |c| c.send(attr) == options[attr] } if options.key?(attr)
         end
diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index 2d71ee2f15..88c2ac5d0a 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -139,8 +139,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
     with_real_execute do
       ActiveRecord::Base.connection.create_table :delete_me
       ActiveRecord::Base.connection.add_timestamps :delete_me, null: true
-      assert column_present?("delete_me", "updated_at", "datetime")
-      assert column_present?("delete_me", "created_at", "datetime")
+      assert column_exists?("delete_me", "updated_at", "datetime")
+      assert column_exists?("delete_me", "created_at", "datetime")
     ensure
       ActiveRecord::Base.connection.drop_table :delete_me rescue nil
     end
@@ -152,8 +152,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
         t.timestamps null: true
       end
       ActiveRecord::Base.connection.remove_timestamps :delete_me, null: true
-      assert_not column_present?("delete_me", "updated_at", "datetime")
-      assert_not column_present?("delete_me", "created_at", "datetime")
+      assert_not column_exists?("delete_me", "updated_at", "datetime")
+      assert_not column_exists?("delete_me", "created_at", "datetime")
     ensure
       ActiveRecord::Base.connection.drop_table :delete_me rescue nil
     end
@@ -194,9 +194,4 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
     def method_missing(method_symbol, *arguments)
       ActiveRecord::Base.connection.send(method_symbol, *arguments)
     end
-
-    def column_present?(table_name, column_name, type)
-      results = ActiveRecord::Base.connection.select_all("SHOW FIELDS FROM #{table_name} LIKE '#{column_name}'")
-      results.first && results.first["Type"] == type
-    end
 end