init commit

2c7e223a4ced4849feb1b3209cef1faf61666eba
commit 2c7e223a4ced4849feb1b3209cef1faf61666eba
diff --git a/Lib/test/test_warnings/__init__.py b/Lib/test/test_warnings/__init__.py
@@ -820,6 +820,16 @@ def test_issue31416(self):
                  self.assertRaises(TypeError):
                 wmod.warn_explicit('foo', Warning, 'bar', 1)
 
+    @support.cpython_only
+    def test_issue31566(self):
+        # warn() shouldn't cause an assertion failure in case of a bad
+        # __name__ global.
+        wmod = self.module
+        with support.swap_item(globals(), '__name__', b'foo'), \
+             support.swap_item(globals(), '__file__', None), \
+             support.captured_stderr():
+            wmod.warn('bar')
+
 
 class WarningsDisplayTests(BaseTest):
 

diff --git a/Misc/NEWS.d/next/Core and Builtins/2017-09-24-09-57-04.bpo-31566.OxwINs.rst b/Misc/NEWS.d/next/Core and Builtins/2017-09-24-09-57-04.bpo-31566.OxwINs.rst
@@ -0,0 +1,2 @@
+Fix an assertion failure in `_warnings.warn()` in case of a bad
+``__name__`` global. Patch by Oren Milman.
diff --git a/Python/_warnings.c b/Python/_warnings.c
@@ -684,7 +684,7 @@ setup_context(Py_ssize_t stack_level, PyObject **filename, int *lineno,
 
     /* Setup module. */
     *module = PyDict_GetItemString(globals, "__name__");
-    if (*module == NULL) {
+    if (*module == NULL || !PyUnicode_Check(*module)) {
         *module = PyUnicode_FromString("<string>");
         if (*module == NULL)
             goto handle_error;
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Fix an assertion failure in `_warnings.warn()` in case of a bad
		``__name__`` global. Patch by Oren Milman.