Ref #23643 -- Added plain text report of exception chain.

{% else %}

   {{ source_line.0 }} : {{ source_line.1 }}

{% endifequal %}{% endfor %}{% endif %}

Traceback:

{% for frame in frames %}File "{{ frame.filename|escape }}" in {{ frame.function|escape }}

{% if frame.context_line %}  {{ frame.lineno }}. {{ frame.context_line|escape }}{% endif %}

{% endfor %}

Traceback:{% for frame in frames %}

{% ifchanged frame.exc_cause %}{% if frame.exc_cause %}{% if frame.exc_cause_explicit %}

The above exception ({{ frame.exc_cause }}) was the direct cause of the following exception:

{% else %}

During handling of the above exception ({{ frame.exc_cause }}), another exception occurred:

{% endif %}{% endif %}{% endifchanged %}

File "{{ frame.filename|escape }}" in {{ frame.function|escape }}

{% if frame.context_line %}  {{ frame.lineno }}. {{ frame.context_line|escape }}{% endif %}{% endfor %}

Exception Type: {{ exception_type|escape }}{% if request %} at {{ request.path_info|escape }}{% endif %}

Exception Value: {{ exception_value|force_escape }}

</textarea>

        explicit_exc = 'The above exception ({0}) was the direct cause of the following exception:'

        implicit_exc = 'During handling of the above exception ({0}), another exception occurred:'

        reporter = ExceptionReporter(request, exc_type, exc_value, tb)

        html = reporter.get_traceback_html()

        self.assertIn(explicit_exc.format("Top level"), html)

        self.assertIn(implicit_exc.format("Second exception"), html)

        # Both messages are twice on page -- one rendered as html,

        # one as plain text (for pastebin)

        self.assertEqual(2, html.count(explicit_exc.format("Top level")))

        self.assertEqual(2, html.count(implicit_exc.format("Second exception")))

        text = reporter.get_traceback_text()

        self.assertIn(explicit_exc.format("Top level"), text)