Range types not properly converted to SQL in QuerySet.query.__str__()

[Villiers Strauss]

The string representation of the QuerySet.query object, which is useful in debugging, does not convert range types to their SQL equivalents, instead it just displays the string representation of the range type.

>>> import datetime
>>> from django.utils.timezone import utc
>>> from psycopg.extras import NumericRange, DateRange, DateTimeTZRange
>>> from myapp.models import MyModel  # model defintion is irrelevant

>>> print(MyModel.objects.filter(num_rng__overlap=NumericRange(1, 5)).query)
SELECT [...] FROM "myapp_mymodel" WHERE ("myapp_mymodel"."num_rng" && NumericRange(1, 5, '[)'))

>>> print(MyModel.objects.filter(date_rng__overlap=DateRange(datetime.date(2015, 5, 1), datetime.date(2015, 6, 1))).query)
SELECT [...] FROM "myapp_mymodel" WHERE ("myapp_mymodel"."date_rng" && DateRange(datetime.date(2015, 5, 1), datetime.date(2015, 6, 1), '[)'))

>>> print(MyModel.objects.filter(dt_rng__overlap=DateTimeTZRange(datetime.datetime(2015, 5, 1, tzinfo=utc), datetime.datetime(2015, 6, 1, tzinfo=utc))).query)
SELECT [...] FROM "myapp_mymodel" WHERE ("myapp_mymodel"."dt_rng" && DateTimeTZRange(datetime.datetime(2015, 5, 1, 0, 0, tzinfo=<UTC>), datetime.datetime(2015, 6, 1, 0, 0, tzinfo=<UTC>), '[)'))

The expected output is numrange(1.0, 5.0), daterange('2015-05-01', '2015-06-01') and tstzrange('2015-05-01 00:00:00+00:00', '2015-06-01 00:00:00+00:00') respectively.