WIP add test for pytest-dev#349

testing/acceptance_test.py

@@ -430,7 +430,7 @@ def test_func(request):
         result.stdout.fnmatch_lines(["*this is a warning*", "*1 passed, 1 warnings*"])
 
     @pytest.mark.parametrize("n", ["-n0", "-n1"])
-    def test_custom_subclass(self, testdir, n):
+    def test_custom_warning_subclass(self, testdir, n):
         """Check that warning subclasses that don't honor the args attribute don't break
         pytest-xdist (#344)
         """
@@ -458,6 +458,27 @@ def test_func(request):
         result = testdir.runpytest(n)
         result.stdout.fnmatch_lines(["*MyWarning*", "*1 passed, 1 warnings*"])
 
+    @pytest.mark.parametrize("n", ["-n0", "-n1"])
+    def test_warning_unserializable_arg(self, testdir, n):
+        """Check that warning with args that can't be serialized don't choke xdist (#349)"""
+        from pkg_resources import parse_version
+
+        if parse_version(pytest.__version__) < parse_version("3.1"):
+            pytest.skip("pytest warnings requires >= 3.1")
+
+        testdir.makepyfile(
+            """
+            import warnings
+
+            def test_func(tmpdir):
+                with open(str(tmpdir / 'foo.txt'), 'w') as f:
+                    warnings.warn(UserWarning(f))
+        """
+        )
+        testdir.syspathinsert()
+        result = testdir.runpytest(n)
+        result.stdout.fnmatch_lines(["*UserWarning*foo.txt*", "*1 passed, 1 warnings*"])
+
     def test_logfinish_hook(self, testdir):
         """Ensure the pytest_runtest_logfinish hook is being properly handled"""
         from _pytest import hookspec