Add an optional test for greenlet C++ exceptions

tests/__init__.py

@@ -19,6 +19,15 @@
  include_dirs=[os.path.curdir]),
 ]
 
+if os.environ.get('GREENLET_TEST_CPP'):
+ TEST_EXTENSIONS_CPP = [
+ Extension('_test_extension_cpp',
+ [os.path.join('tests', '_test_extension_cpp.cpp')],
+ language="c++",
+ include_dirs=[os.path.curdir]),
+ ]
+else:
+ TEST_EXTENSIONS_CPP = []
 
 def test_collector():
  """Collect all tests under the tests directory and return a
@@ -29,6 +38,8 @@ def test_collector():
  test_module_list = [
  'tests.%s' % os.path.splitext(os.path.basename(t))[0]
  for t in glob.glob(os.path.join(tests_dir, 'test_*.py'))]
+ if not TEST_EXTENSIONS_CPP:
+ test_module_list.remove('tests.test_cpp')
  return unittest.TestLoader().loadTestsFromNames(test_module_list)
 
 def build_test_extensions():
@@ -46,4 +57,4 @@ def build_test_extensions():
  'build': {'build_base': os.path.join('build', 'tests')},
  },
  script_args=['build_ext', '-i'],
- ext_modules=TEST_EXTENSIONS)
+ ext_modules=TEST_EXTENSIONS + TEST_EXTENSIONS_CPP)

tests/_test_extension_cpp.cpp

@@ -0,0 +1,118 @@
+/* This is a set of functions used to test C++ exceptions are not
+ * broken during greenlet switches
+ */
+
+#include "../greenlet.h"
+
+struct exception_t
+{
+ int depth;
+ exception_t(int depth) : depth(depth) { }
+};
+
+/* Functions are called via pointers to prevent inlining */
+static void (*p_test_exception_throw)(int depth);
+static PyObject* (*p_test_exception_switch_recurse)(int depth, int left);
+
+static void test_exception_throw(int depth)
+{
+ throw exception_t(depth);
+}
+
+static PyObject* test_exception_switch_recurse(int depth, int left)
+{
+ if (left > 0) {
+ return p_test_exception_switch_recurse(depth, left - 1);
+ }
+
+ PyObject* result = NULL;
+ PyGreenlet* self = PyGreenlet_GetCurrent();
+ if (self == NULL)
+ return NULL;
+
+ try {
+ PyGreenlet_Switch(self->parent, NULL, NULL);
+ p_test_exception_throw(depth);
+ PyErr_SetString(PyExc_RuntimeError, "throwing C++ exception didn't work");
+ } catch(exception_t& e) {
+ if (e.depth != depth)
+ PyErr_SetString(PyExc_AssertionError, "depth mismatch");
+ else
+ result = PyLong_FromLong(depth);
+ } catch(...) {
+ PyErr_SetString(PyExc_RuntimeError, "unexpected C++ exception");
+ }
+
+ Py_DECREF(self);
+ return result;
+}
+
+/* test_exception_switch(int depth)
+ * - recurses depth times
+ * - switches to parent inside try/catch block
+ * - throws an exception that (expected to be caught in the same function)
+ * - verifies depth matches (exceptions shouldn't be caught in other greenlets)
+ */
+static PyObject *
+test_exception_switch(PyObject *self, PyObject *args)
+{
+ int depth;
+ if (!PyArg_ParseTuple(args, "i", &depth))
+ return NULL;
+ return p_test_exception_switch_recurse(depth, depth);
+}
+
+static PyMethodDef test_methods[] = {
+ {"test_exception_switch", (PyCFunction)&test_exception_switch, METH_VARARGS,
+ "Switches to parent twice, to test exception handling and greenlet switching."},
+ {NULL, NULL, 0, NULL}
+};
+
+
+#if PY_MAJOR_VERSION >= 3
+#define INITERROR return NULL
+
+static struct PyModuleDef moduledef = {
+ PyModuleDef_HEAD_INIT,
+ "_test_extension_cpp",
+ NULL,
+ 0,
+ test_methods,
+ NULL,
+ NULL,
+ NULL,
+ NULL
+};
+
+PyMODINIT_FUNC
+PyInit__test_extension_cpp(void)
+#else
+#define INITERROR return
+PyMODINIT_FUNC
+init_test_extension_cpp(void)
+#endif
+{
+ PyObject *module = NULL;
+
+#if PY_MAJOR_VERSION >= 3
+ module = PyModule_Create(&moduledef);
+#else
+ module = Py_InitModule("_test_extension_cpp", test_methods);
+#endif
+
+ if (module == NULL) {
+ INITERROR;
+ }
+
+ PyGreenlet_Import();
+ if (_PyGreenlet_API == NULL) {
+ INITERROR;
+ }
+
+ p_test_exception_throw = test_exception_throw;
+ p_test_exception_switch_recurse = test_exception_switch_recurse;
+
+#if PY_MAJOR_VERSION >= 3
+ return module;
+#endif
+}

tests/test_cpp.py

@@ -0,0 +1,14 @@
+import unittest
+
+import greenlet
+import _test_extension_cpp
+
+class CPPTests(unittest.TestCase):
+ def test_exception_switch(self):
+ greenlets = []
+ for i in range(4):
+ g = greenlet.greenlet(_test_extension_cpp.test_exception_switch)
+ g.switch(i)
+ greenlets.append(g)
+ for i,g in enumerate(greenlets):
+ self.assertEqual(g.switch(), i)