Fixed test for pytest 2

Author: Sylvain MARIE

pytest_cases/tests/issues/test_issue_fixture_union1.py

@@ -1,3 +1,5 @@
+from distutils.version import LooseVersion
+
 import pytest
 from pytest_cases import fixture_union
 
@@ -15,4 +17,8 @@ def test_foo(u):
 
 
 def test_synthesis(module_results_dct):
-    assert list(module_results_dct) == ['test_foo[u_is_a0]', 'test_foo[u_is_a1]']
+    if LooseVersion(pytest.__version__) < LooseVersion('3.0.0'):
+        # the way to make ids uniques in case of duplicates was different in old pytest
+        assert list(module_results_dct) == ['test_foo[u_is_0a]', 'test_foo[u_is_1a]']
+    else:
+        assert list(module_results_dct) == ['test_foo[u_is_a0]', 'test_foo[u_is_a1]']