from io import StringIO

from django.core.management import call_command

from django.test.utils import modify_settings

from . import PostgreSQLTestCase

@modify_settings(INSTALLED_APPS={"append": "django.contrib.postgres"})

class InspectDBTests(PostgreSQLTestCase):

    def assertFieldsInModel(self, model, field_outputs):

        out = StringIO()

        call_command(

            "inspectdb",

            table_name_filter=lambda tn: tn.startswith(model),

            stdout=out,

        )

        output = out.getvalue()

        for field_output in field_outputs:

            self.assertIn(field_output, output)

    def test_range_fields(self):

        self.assertFieldsInModel(

            "postgres_tests_rangesmodel",

            [

                "ints = django.contrib.postgres.fields.IntegerRangeField(blank=True, "

                "null=True)",

                "bigints = django.contrib.postgres.fields.BigIntegerRangeField("

                "blank=True, null=True)",

                "decimals = django.contrib.postgres.fields.DecimalRangeField("

                "blank=True, null=True)",

                "timestamps = django.contrib.postgres.fields.DateTimeRangeField("

                "blank=True, null=True)",

                "dates = django.contrib.postgres.fields.DateRangeField(blank=True, "

                "null=True)",

            ],

        )