Added ArrowType, moved coercion_listener test setup to init

setup.py

@@ -55,6 +55,7 @@ setup(
             'flexmock>=0.9.7',
             'psycopg2>=2.4.6'
         ],
+        'arrow': ['arrow>=0.3.4'],
         'phone': ['phonenumbers3k==5.6b1'],
         'password': ['passlib >= 1.6, < 2.0'],
         'color': ['colour>=0.0.4']

sqlalchemy_utils/types/__init__.py

@@ -2,6 +2,7 @@ from functools import wraps
 from sqlalchemy.orm.collections import InstrumentedList as _InstrumentedList
 from sqlalchemy import types
 from sqlalchemy.dialects.postgresql.base import ischema_names
+from .arrow import ArrowType
 from .color import ColorType
 from .email import EmailType
 from .ip_address import IPAddressType
@@ -18,6 +19,7 @@ from .uuid import UUIDType
 
 
 __all__ = (
+    ArrowType,
     ColorType,
     EmailType,
     IPAddressType,

sqlalchemy_utils/types/arrow.py

@@ -0,0 +1,45 @@
+from __future__ import absolute_import
+from collections import Iterable
+from datetime import datetime
+import six
+
+arrow = None
+try:
+    import arrow
+except:
+    pass
+from sqlalchemy import types
+from sqlalchemy_utils import ImproperlyConfigured
+
+
+class ArrowType(types.TypeDecorator):
+    impl = types.DateTime
+
+    def __init__(self, *args, **kwargs):
+        if not arrow:
+            raise ImproperlyConfigured(
+                "'arrow' package is required to use 'ArrowType'"
+            )
+
+        super(ArrowType, self).__init__(*args, **kwargs)
+
+    def process_bind_param(self, value, dialect):
+        if value:
+            return value.datetime
+        return value
+
+    def process_result_value(self, value, dialect):
+        if value:
+            return arrow.get(value)
+        return value
+
+    def coercion_listener(self, target, value, oldvalue, initiator):
+        if value is None:
+            return None
+        elif isinstance(value, six.string_types):
+            value = arrow.get(value)
+        elif isinstance(value, Iterable):
+            value = arrow.get(*value)
+        elif isinstance(value, datetime):
+            value = arrow.get(value)
+        return value

tests/__init__.py

@@ -6,6 +6,7 @@ from sqlalchemy.orm import sessionmaker
 from sqlalchemy.ext.declarative import declarative_base
 
 from sqlalchemy_utils import InstrumentedList
+from sqlalchemy_utils import coercion_listener
 
 
 @sa.event.listens_for(sa.engine.Engine, 'before_cursor_execute')
@@ -19,6 +20,9 @@ def count_sql_calls(conn, cursor, statement, parameters, context, executemany):
 warnings.simplefilter('error', sa.exc.SAWarning)
 
 
+sa.event.listen(sa.orm.mapper, 'mapper_configured', coercion_listener)
+
+
 class TestCase(object):
     dns = 'sqlite:///:memory:'
 

tests/test_arrow.py

@@ -0,0 +1,33 @@
+from datetime import datetime
+from pytest import mark
+import sqlalchemy as sa
+from sqlalchemy_utils.types import arrow
+from tests import TestCase
+
+
+@mark.xfail('arrow.arrow is None')
+class TestArrowDateTimeType(TestCase):
+    def create_models(self):
+        class Article(self.Base):
+            __tablename__ = 'article'
+            id = sa.Column(sa.Integer, primary_key=True)
+            created_at = sa.Column(arrow.ArrowType)
+
+        self.Article = Article
+
+    def test_parameter_processing(self):
+        article = self.Article(
+            created_at=arrow.arrow.get(datetime(2000, 11, 1))
+        )
+
+        self.session.add(article)
+        self.session.commit()
+
+        article = self.session.query(self.Article).first()
+        assert article.created_at.datetime
+
+    def test_string_coercion(self):
+        article = self.Article(
+            created_at='1367900664'
+        )
+        assert article.created_at.year == 2013

tests/test_color.py

@@ -1,6 +1,6 @@
 from pytest import mark
 import sqlalchemy as sa
-from sqlalchemy_utils import ColorType, coercion_listener
+from sqlalchemy_utils import ColorType
 from sqlalchemy_utils.types import color
 from tests import TestCase
 
@@ -17,8 +17,6 @@ class TestColorType(TestCase):
                 return 'Document(%r)' % self.id
 
         self.Document = Document
-        sa.event.listen(sa.orm.mapper, 'mapper_configured', coercion_listener)
-
 
     def test_color_parameter_processing(self):
         from colour import Color

tests/test_password.py

@@ -2,7 +2,7 @@ from pytest import mark
 import sqlalchemy as sa
 from tests import TestCase
 from sqlalchemy_utils.types import password
-from sqlalchemy_utils import Password, PasswordType, coercion_listener
+from sqlalchemy_utils import Password, PasswordType
 
 
 @mark.xfail('password.passlib is None')
@@ -25,7 +25,6 @@ class TestPasswordType(TestCase):
                 return 'User(%r)' % self.id
 
         self.User = User
-        sa.event.listen(sa.orm.mapper, 'mapper_configured', coercion_listener)
 
     def test_encrypt(self):
         """Should encrypt the password on setting the attribute."""

tests/test_phonenumber_type.py

@@ -1,7 +1,7 @@
 from pytest import mark
 from tests import TestCase
 import sqlalchemy as sa
-from sqlalchemy_utils import PhoneNumberType, PhoneNumber, coercion_listener
+from sqlalchemy_utils import PhoneNumberType, PhoneNumber
 from sqlalchemy_utils.types import phone_number
 
 
@@ -60,7 +60,6 @@ class TestPhoneNumberType(TestCase):
             phone_number = sa.Column(PhoneNumberType())
 
         self.User = User
-        sa.event.listen(sa.orm.mapper, 'mapper_configured', coercion_listener)
 
     def setup_method(self, method):
         super(TestPhoneNumberType, self).setup_method(method)

tests/test_uuid.py

@@ -1,11 +1,10 @@
 import sqlalchemy as sa
 from tests import TestCase
-from sqlalchemy_utils import UUIDType, coercion_listener
+from sqlalchemy_utils import UUIDType
 import uuid
 
 
 class TestUUIDType(TestCase):
-
     def create_models(self):
         class User(self.Base):
             __tablename__ = 'user'
@@ -15,7 +14,6 @@ class TestUUIDType(TestCase):
                 return 'User(%r)' % self.id
 
         self.User = User
-        sa.event.listen(sa.orm.mapper, 'mapper_configured', coercion_listener)
 
     def test_commit(self):
         obj = self.User()