format_suffix_pattern not working with path() in django 2.0

[mr-skyaakash]

Checklist

• I have verified that that issue exists against the master branch of Django REST framework.
• I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• This is not a usage question. (Those should be directed to the discussion group instead.)
• This cannot be dealt with as a third party library. (We prefer new functionality to be in the form of third party libraries where possible.)
• I have reduced the issue to the simplest possible case.
• I have included a failing test as a pull request. (If you are unable to do so we can still accept the issue.)

Steps to reproduce

Expected behavior

when using format_suffix_patterns() from the rest_framwork.urlpatterns class, it should format the url pattern for url() from django.conf.urls as well as the newly introduced path() from django.urls

Actual behavior

getting an error when using path() in urlpatterns[], and then formatting it using the format_suffix_patterns() method

[xordoquy]

Next step on that issue would be to write a failing test case.

[adjordan]

I am having the same issue with the following urls.py file:

from django.urls import path, re_path
from rest_framework.urlpatterns import format_suffix_patterns
from snippets import views

urlpatterns = [
    path('snippets/', views.snippet_list),
    re_path('snippets/(?P<pk>[0-9]+)/', views.snippet_detail)
]

urlpatterns = format_suffix_patterns(urlpatterns)