Improve test to ensure the expected function is re-raised

Author: nicoddemus

_pytest/fixtures.py

@@ -742,7 +742,10 @@ def finish(self):
                 except:
                     exceptions.append(sys.exc_info())
             if exceptions:
-                py.builtin._reraise(*exceptions[0])
+                e = exceptions[0]
+                del exceptions  # ensure we don't keep all frames alive because of the traceback
+                py.builtin._reraise(*e)
+
         finally:
             ihook = self._fixturemanager.session.ihook
             ihook.pytest_fixture_post_finalizer(fixturedef=self)

changelog/2440.bugfix

@@ -1 +1 @@
-Exceptions in a SubRequest's finish() block are suppressed until all finalizers are called, with the initial exception reraised.
+Exceptions raised during teardown by finalizers are now suppressed until all finalizers are called, with the initial exception reraised.

testing/python/fixture.py

@@ -658,30 +658,37 @@ def test_second():
             ])
 
     def test_request_subrequest_addfinalizer_exceptions(self, testdir):
+        """
+        Ensure exceptions raised during teardown by a finalizer are suppressed
+        until all finalizers are called, re-raising the first exception (#2440)
+        """
         testdir.makepyfile("""
             import pytest
             l = []
-            def _excepts():
-                raise Exception('Error')
+            def _excepts(where):
+                raise Exception('Error in %s fixture' % where)
             @pytest.fixture
             def subrequest(request):
                 return request
             @pytest.fixture
             def something(subrequest):
                 subrequest.addfinalizer(lambda: l.append(1))
                 subrequest.addfinalizer(lambda: l.append(2))
-                subrequest.addfinalizer(_excepts)
+                subrequest.addfinalizer(lambda: _excepts('something'))
             @pytest.fixture
             def excepts(subrequest):
-                subrequest.addfinalizer(_excepts)
+                subrequest.addfinalizer(lambda: _excepts('excepts'))
                 subrequest.addfinalizer(lambda: l.append(3))
             def test_first(something, excepts):
                 pass
             def test_second():
                 assert l == [3, 2, 1]
         """)
-        reprec = testdir.inline_run()
-        reprec.assertoutcome(passed=2, failed=1)
+        result = testdir.runpytest()
+        result.stdout.fnmatch_lines([
+            '*Exception: Error in excepts fixture',
+            '* 2 passed, 1 error in *',
+        ])
 
     def test_request_getmodulepath(self, testdir):
         modcol = testdir.getmodulecol("def test_somefunc(): pass")