Fixed #28485 -- Made ExceptionReporter.get_traceback_frames() include frames without source code.

AUTHORS

@@ -514,6 +514,7 @@ answer newbie questions, and generally made Django that much better:
     Martin Kosír <martin@martinkosir.net>
     Martin Mahner <http://www.mahner.org/>
     Martin Maney <http://www.chipy.org/Martin_Maney>
+    Martin von Gagern <gagern@google.com>
     Mart Sõmermaa <http://mrts.pri.ee/>
     Marty Alchin <gulopine@gamemusic.org>
     masonsimon+django@gmail.com

django/views/debug.py

@@ -418,7 +418,11 @@ class ExceptionReporter:
             pre_context_lineno, pre_context, context_line, post_context = self._get_lines_from_file(
                 filename, lineno, 7, loader, module_name,
             )
-            if pre_context_lineno is not None:
+            if pre_context_lineno is None:
+                pre_context_lineno = lineno
+                pre_context = []
+                context_line = '<source code not available>'
+                post_context = []
             frames.append({
                 'exc_cause': explicit_or_implicit_cause(exc_value),
                 'exc_cause_explicit': getattr(exc_value, '__cause__', True),

tests/view_tests/tests/test_debug.py

@@ -375,6 +375,27 @@ class ExceptionReporterTests(SimpleTestCase):
         self.assertIn(implicit_exc.format("Second exception"), text)
         self.assertEqual(3, text.count('<p>Final exception</p>'))
 
+    def test_reporting_frames_without_source(self):
+        try:
+            source = "def funcName():\n    raise Error('Whoops')\nfuncName()"
+            namespace = {}
+            code = compile(source, 'generated', 'exec')
+            exec(code, namespace)
+        except Exception:
+            exc_type, exc_value, tb = sys.exc_info()
+        request = self.rf.get('/test_view/')
+        reporter = ExceptionReporter(request, exc_type, exc_value, tb)
+        frames = reporter.get_traceback_frames()
+        last_frame = frames[-1]
+        self.assertEqual(last_frame['context_line'], '<source code not available>')
+        self.assertEqual(last_frame['filename'], 'generated')
+        self.assertEqual(last_frame['function'], 'funcName')
+        self.assertEqual(last_frame['lineno'], 2)
+        html = reporter.get_traceback_html()
+        self.assertIn('generated in funcName', html)
+        text = reporter.get_traceback_text()
+        self.assertIn('"generated" in funcName', text)
+
     def test_request_and_message(self):
         "A message can be provided in addition to a request"
         request = self.rf.get('/test_view/')