Begin to write scenario-based tests

3 files changed, 55 insertions, 15 deletions

diff --git a/testtools/testcase.py b/testtools/testcase.py
index 160351c..d219175 100644
--- a/testtools/testcase.py
+++ b/testtools/testcase.py
@@ -206,11 +206,7 @@ class TestCase(unittest.TestCase):
         # Generators to ensure unique traceback ids.  Maps traceback label to
         # iterators.
         self._traceback_id_gens = {}
-        self.__setup_called = False
-        self.__teardown_called = False
-        # __details is lazy-initialized so that a constructed-but-not-run
-        # TestCase is safe to use with clone_test_with_new_id.
-        self.__details = None
+        self._reset()
         test_method = self._get_test_method()
         if runTest is None:
             runTest = getattr(
@@ -230,6 +226,15 @@ class TestCase(unittest.TestCase):
             (Exception, self._report_error),
             ]
 
+    def _reset(self):
+        """Reset the test case as if it had never been run."""
+        self._traceback_id_gens = {}
+        self.__setup_called = False
+        self.__teardown_called = False
+        # __details is lazy-initialized so that a constructed-but-not-run
+        # TestCase is safe to use with clone_test_with_new_id.
+        self.__details = None
+
     def __eq__(self, other):
         eq = getattr(unittest.TestCase, '__eq__', None)
         if eq is not None and not unittest.TestCase.__eq__(self, other):
@@ -596,6 +601,7 @@ class TestCase(unittest.TestCase):
         result.addUnexpectedSuccess(self, details=self.getDetails())
 
     def run(self, result=None):
+        self._reset()
         try:
             run_test = self.__RunTest(
                 self, self.exception_handlers, last_resort=self._report_error)
diff --git a/testtools/tests/samplecases.py b/testtools/tests/samplecases.py
new file mode 100644
index 0000000..4f0f12a
--- /dev/null
+++ b/testtools/tests/samplecases.py
@@ -0,0 +1,31 @@
+# Copyright (c) 2015 testtools developers. See LICENSE for details.
+
+"""A collection of sample TestCases.
+
+These are primarily of use in testing the test framework.
+"""
+
+from testtools import TestCase
+
+
+class _NormalTest(TestCase):
+
+    def test_success(self):
+        pass
+
+    def test_error(self):
+        1/0
+
+    def test_failure(self):
+        self.fail('arbitrary failure')
+
+
+"""
+A list that can be used with testscenarios to test every kind of sample
+case that we have.
+"""
+all_sample_cases_scenarios = [
+    ('simple-success-test', {'case': _NormalTest('test_success')}),
+    ('simple-error-test', {'case': _NormalTest('test_error')}),
+    ('simple-failure-test', {'case': _NormalTest('test_failure')}),
+]
diff --git a/testtools/tests/test_testcase.py b/testtools/tests/test_testcase.py
index 695b1a5..c3f8a93 100644
--- a/testtools/tests/test_testcase.py
+++ b/testtools/tests/test_testcase.py
@@ -54,6 +54,7 @@ from testtools.tests.helpers import (
     FullStackRunTest,
     LoggingResult,
     )
+from testtools.tests.samplecases import all_sample_cases_scenarios
 
 
 class TestPlaceHolder(TestCase):
@@ -1277,19 +1278,21 @@ class TestRunTwice(TestCase):
     # 'run_tests_with'.
     run_tests_with = FullStackRunTest
 
+    scenarios = all_sample_cases_scenarios
+
     def test_runTwice(self):
-        # Tests can be run twice.
-        class NormalTest(TestCase):
-            def test_method(self):
-                pass
-        test = NormalTest('test_method')
-        result = unittest.TestResult()
-        test.run(result)
-        test.run(result)
-        self.expectThat(result.errors, HasLength(0))
-        self.assertThat(result.testsRun, Equals(2))
+        # Tests that are intrinsically determistic can be run twice and
+        # produce exactly the same results each time, without need for
+        # explicit resetting or reconstruction.
+        test = self.case
+        first_result = ExtendedTestResult()
+        test.run(first_result)
+        second_result = ExtendedTestResult()
+        test.run(second_result)
+        self.assertEqual(first_result._events, second_result._events)
 
     def test_runTwiceTearDownFailure(self):
+        # XXX: jml: you should move this into _samplecases.
         # Tests can be run twice, even if tearDown fails.
         class NormalTest(TestCase):
             def test_method(self):