Add `unsigned` types for numeric data types in MySQL

In the case of using `unsigned` as the type:

    create_table :foos do |t|
      t.unsigned_integer :unsigned_integer
      t.unsigned_bigint  :unsigned_bigint
      t.unsigned_float   :unsigned_float
      t.unsigned_decimal :unsigned_decimal, precision: 10, scale: 2
    end

4 files changed, 56 insertions, 0 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 8c53069f5b..1f300dea5d 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -9,6 +9,15 @@
           t.decimal :unsigned_decimal, unsigned: true, precision: 10, scale: 2
         end
 
+    In the case of using `unsigned` as the type:
+
+        create_table :foos do |t|
+          t.unsigned_integer :unsigned_integer
+          t.unsigned_bigint  :unsigned_bigint
+          t.unsigned_float   :unsigned_float
+          t.unsigned_decimal :unsigned_decimal, precision: 10, scale: 2
+        end
+
     *Ryuta Kamizono*
 
 *   Lookup the attribute name for `restrict_with_error` messages on the
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index 55de098f70..245d476abb 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -14,6 +14,22 @@ module ActiveRecord
         def json(*args, **options)
           args.each { |name| column(name, :json, options) }
         end
+
+        def unsigned_integer(*args, **options)
+          args.each { |name| column(name, :unsigned_integer, options) }
+        end
+
+        def unsigned_bigint(*args, **options)
+          args.each { |name| column(name, :unsigned_bigint, options) }
+        end
+
+        def unsigned_float(*args, **options)
+          args.each { |name| column(name, :unsigned_float, options) }
+        end
+
+        def unsigned_decimal(*args, **options)
+          args.each { |name| column(name, :unsigned_decimal, options) }
+        end
       end
 
       class ColumnDefinition < ActiveRecord::ConnectionAdapters::ColumnDefinition
@@ -29,6 +45,9 @@ module ActiveRecord
           when :primary_key
             column.type = :integer
             column.auto_increment = true
+          when /\Aunsigned_(?<type>.+)\z/
+            column.type = $~[:type].to_sym
+            column.unsigned = true
           end
           column.unsigned ||= options[:unsigned]
           column.charset = options[:charset]
@@ -1108,6 +1127,8 @@ module ActiveRecord
       ActiveRecord::Type.register(:json, MysqlJson, adapter: :mysql2)
       ActiveRecord::Type.register(:string, MysqlString, adapter: :mysql)
       ActiveRecord::Type.register(:string, MysqlString, adapter: :mysql2)
+      ActiveRecord::Type.register(:unsigned_integer, Type::UnsignedInteger, adapter: :mysql)
+      ActiveRecord::Type.register(:unsigned_integer, Type::UnsignedInteger, adapter: :mysql2)
     end
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql/unsigned_type_test.rb b/activerecord/test/cases/adapters/mysql/unsigned_type_test.rb
index 12c52b97b6..84c5394c2e 100644
--- a/activerecord/test/cases/adapters/mysql/unsigned_type_test.rb
+++ b/activerecord/test/cases/adapters/mysql/unsigned_type_test.rb
@@ -42,6 +42,19 @@ class MysqlUnsignedTypeTest < ActiveRecord::MysqlTestCase
     end
   end
 
+  test "schema definition can use unsigned as the type" do
+    @connection.change_table("unsigned_types") do |t|
+      t.unsigned_integer :unsigned_integer_t
+      t.unsigned_bigint  :unsigned_bigint_t
+      t.unsigned_float   :unsigned_float_t
+      t.unsigned_decimal :unsigned_decimal_t, precision: 10, scale: 2
+    end
+
+    @connection.columns("unsigned_types").select { |c| /^unsigned_/ === c.name }.each do |column|
+      assert column.unsigned?
+    end
+  end
+
   test "schema dump includes unsigned option" do
     schema = dump_table_schema "unsigned_types"
     assert_match %r{t.integer\s+"unsigned_integer",\s+limit: 4,\s+unsigned: true$}, schema
diff --git a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
index aea2ef4af5..a6f6dd21bb 100644
--- a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
@@ -42,6 +42,19 @@ class Mysql2UnsignedTypeTest < ActiveRecord::Mysql2TestCase
     end
   end
 
+  test "schema definition can use unsigned as the type" do
+    @connection.change_table("unsigned_types") do |t|
+      t.unsigned_integer :unsigned_integer_t
+      t.unsigned_bigint  :unsigned_bigint_t
+      t.unsigned_float   :unsigned_float_t
+      t.unsigned_decimal :unsigned_decimal_t, precision: 10, scale: 2
+    end
+
+    @connection.columns("unsigned_types").select { |c| /^unsigned_/ === c.name }.each do |column|
+      assert column.unsigned?
+    end
+  end
+
   test "schema dump includes unsigned option" do
     schema = dump_table_schema "unsigned_types"
     assert_match %r{t.integer\s+"unsigned_integer",\s+limit: 4,\s+unsigned: true$}, schema