Quotes around filter string omitted in query __str__()

[Aur Saraf]

Very low severity, and probably easy pickings:

In various versions of Django, up to 1.11.5, with sqlite, on Windows:

class M(models.Model):
    field = models.CharField(max_length=10)

>>> from bug import models
>>> print models.M.objects.filter(field='I am a string, look at me').query.__str__()
SELECT "bug_m"."id", "bug_m"."field" FROM "bug_m" WHERE "bug_m"."field" = I am a string, look at me
>>> models.M.objects.filter(field='I am a string, look at me')
<QuerySet []>
>>> from django.db import connection
>>> print connection.queries[-1]['sql']
SELECT "bug_m"."id", "bug_m"."field" FROM "bug_m" WHERE "bug_m"."field" = 'I am a string, look at me' LIMIT 21

SELECT "bug_m"."id", "bug_m"."field" FROM "bug_m" WHERE "bug_m"."field" = I am a string, look at me
SELECT "bug_m"."id", "bug_m"."field" FROM "bug_m" WHERE "bug_m"."field" = 'I am a string, look at me' LIMIT 21

WHERE "bug_m"."field" = I am a string, look at me
WHERE "bug_m"."field" = 'I am a string, look at me'

[Adiyat Mubarak]

Hi, this issue also occurs in my OSX and I'm using Django 1.9.6 with MariaDB.
I'm trying to patch this, should I start from 1.11.x branch or master? Also, I don't know where is the file located regarding this issue.
Thanks in advanced.

[Tim Graham]

Duplicate of #25705.