Add test for Cython module usage in subinterpreters. In Py3.5, we should now raise an exception when trying to re-import a module into a different subinterpreter.

1 files changed, 79 insertions, 0 deletions

diff --git a/tests/run/reimport_from_subinterpreter.srctree b/tests/run/reimport_from_subinterpreter.srctree
new file mode 100644
index 000000000..fd3d15941
--- /dev/null
+++ b/tests/run/reimport_from_subinterpreter.srctree
@@ -0,0 +1,79 @@
+# mode: run
+# tag: pep489, subinterpreter
+
+PYTHON setup.py build_ext --inplace
+PYTHON -c 'import subtest; subtest.run_main()'
+PYTHON -c 'import subtest; subtest.run_sub()'
+PYTHON -c 'import subtest; subtest.run_main(); subtest.run_sub()'
+
+######## setup.py ########
+
+from Cython.Build.Dependencies import cythonize
+from distutils.core import setup
+
+setup(
+    ext_modules = cythonize("**/*.pyx"),
+    )
+
+######## subtest.pyx ########
+
+cdef extern from *:
+    """
+    /* Copied from CPython's _testcapi.c module */
+    static PyObject *run_in_subinterpreter(const char *code) {
+        int r;
+        PyThreadState *substate, *mainstate;
+
+        mainstate = PyThreadState_Get();
+
+        PyThreadState_Swap(NULL);
+
+        substate = Py_NewInterpreter();
+        if (substate == NULL) {
+            /* Since no new thread state was created, there is no exception to
+               propagate; raise a fresh one after swapping in the old thread
+               state. */
+            PyThreadState_Swap(mainstate);
+            PyErr_SetString(PyExc_RuntimeError, "sub-interpreter creation failed");
+            return NULL;
+        }
+        r = PyRun_SimpleString(code);
+        Py_EndInterpreter(substate);
+
+        PyThreadState_Swap(mainstate);
+        return PyLong_FromLong(r);
+    }
+    """
+    object run_in_subinterpreter(const char *code)
+
+
+MAIN_HAS_IMPORTED = False
+
+def run_main():
+    global MAIN_HAS_IMPORTED
+    MAIN_HAS_IMPORTED = True
+    import package.subtest
+    from package import subtest
+
+def run_sub():
+    assert 0 == run_in_subinterpreter(b'1+1')
+    assert 0 == run_in_subinterpreter(b'2+2')
+
+    assert 0 == run_in_subinterpreter(b'import package')
+    assert 0 == run_in_subinterpreter(b'import package')
+
+    import sys
+    result = run_in_subinterpreter(b'import package.subtest')
+    if not MAIN_HAS_IMPORTED:
+        assert result == 0, result  # imports only in subinterpreters are ok
+    elif sys.version_info >= (3, 5):
+        assert result == -1, result  # re-import in a different subinterpreter fails in Py3.5+ (with PEP-489)
+    else:
+        assert result == 0, result  # re-import in a different subinterpreter reuses the module in Py<3.5
+
+
+######## package/__init__.py ########
+
+######## package/subtest.pyx ########
+
+print("Module loaded: %s" % __name__)