Allow users to define a custom method for retrieving the first sequence of a given factory.

Signed-off-by: Raphaël Barrois <raphael.barrois@polyconseil.fr>

2 files changed, 24 insertions, 1 deletions

diff --git a/factory/base.py b/factory/base.py
index ff77e77..736a0e6 100644
--- a/factory/base.py
+++ b/factory/base.py
@@ -144,10 +144,16 @@ class BaseFactory(object):
     def __new__(cls, *args, **kwargs):
         raise RuntimeError('You cannot instantiate BaseFactory')
 
-    _next_sequence = 0
+    _next_sequence = None
+
+    @classmethod
+    def _setup_next_sequence(cls):
+        return 0
 
     @classmethod
     def _generate_next_sequence(cls):
+        if cls._next_sequence is None:
+            cls._next_sequence = cls._setup_next_sequence()
         next_sequence = cls._next_sequence
         cls._next_sequence += 1
         return next_sequence
diff --git a/factory/test_base.py b/factory/test_base.py
index b324680..2b8cb14 100644
--- a/factory/test_base.py
+++ b/factory/test_base.py
@@ -74,6 +74,23 @@ class FactoryTestCase(unittest.TestCase):
         self.assertEqual(test_object1.one, 'one1')
         self.assertEqual(test_object1.two, 'two1')
 
+    def testSequenceCustomBegin(self):
+        class TestObjectFactory(Factory):
+            @classmethod
+            def _setup_next_sequence(cls):
+                return 42
+
+            one = declarations.Sequence(lambda n: 'one' + n)
+            two = declarations.Sequence(lambda n: 'two' + n)
+
+        test_object0 = TestObjectFactory.build()
+        self.assertEqual('one42', test_object0.one)
+        self.assertEqual('two42', test_object0.two)
+
+        test_object1 = TestObjectFactory.build()
+        self.assertEqual('one43', test_object1.one)
+        self.assertEqual('two43', test_object1.two)
+
     def testLazyAttribute(self):
         class TestObjectFactory(Factory):
             one = declarations.LazyAttribute(lambda a: 'abc' )