Django urls patterns resolver shadowing exceptions thrown everywhere else

[Ariel Torti]

The new version of django somehow captures all the exceptions ocurred while parsing the urlpatterns.

How to reproduce:

• Create a django project
• Create a an app

app/views.py

from django.shortcuts import render

class MyCustomExceptionShadowed(Exception):
  pass

raise MyCustomExceptionShadowed('I have a description of your error')

# Create your views here.
def myview(request):
  pass

urls.py

from django.contrib import admin
from django.urls import path

from bugtest import views

urlpatterns = [
    path('', views.myview),
    path('admin/', admin.site.urls),
]

When running the server I get

django.core.exceptions.ImproperlyConfigured: The included URLconf 'bug.urls' does not appear to have any patterns in it. If you see valid patterns in the file then the issue is probably caused by a circular import.

When in fact I expect it to say

  File "/home/ariel-nt/Desktop/test/bug/bugtest/views.py", line 6, in <module>
    raise MyCustomExceptionShadowed('I have a description of your error')
bugtest.views.MyCustomExceptionShadowed: I have a description of your error

I tested this with django 2.1 and it works as expected, so I'll now try to find the root cause of the error and give an update here