Fixed #27567 -- Fixed crash in the debug view when request.user errors.

tests/view_tests/tests/test_debug.py

@@ -515,6 +515,33 @@ class ExceptionReporterTests(SimpleTestCase):
         html = reporter.get_traceback_html()
         self.assertInHTML('<td>items</td><td class="code"><pre>&#39;Oops&#39;</pre></td>', html)
 
+    def test_exception_fetching_user(self):
+        """
+        The error page can be rendered if the current user can't be retrieved
+        (such as when the database is unavailable).
+        """
+        class ExceptionUser(object):
+            def __str__(self):
+                raise Exception()
+
+        request = self.rf.get('/test_view/')
+        request.user = ExceptionUser()
+
+        try:
+            raise ValueError('Oops')
+        except ValueError:
+            exc_type, exc_value, tb = sys.exc_info()
+
+        reporter = ExceptionReporter(request, exc_type, exc_value, tb)
+        html = reporter.get_traceback_html()
+        self.assertIn('<h1>ValueError at /test_view/</h1>', html)
+        self.assertIn('<pre class="exception_value">Oops</pre>', html)
+        self.assertIn('<h3 id="user-info">USER</h3>', html)
+        self.assertIn('<p>[unable to retrieve the current user]</p>', html)
+
+        text = reporter.get_traceback_text()
+        self.assertIn('USER: [unable to retrieve the current user]', text)
+
 
 class PlainTextReportTests(SimpleTestCase):
     rf = RequestFactory()