from unittest import skipIf

from django import forms
from django.db import connection, models
from django.test import SimpleTestCase, TestCase

from .models import Post


class TextFieldTests(TestCase):

    def test_max_length_passed_to_formfield(self):
        """
        TextField passes its max_length attribute to form fields created using
        their formfield() method.
        """
        tf1 = models.TextField()
        tf2 = models.TextField(max_length=2345)
        self.assertIsNone(tf1.formfield().max_length)
        self.assertEqual(2345, tf2.formfield().max_length)

    def test_choices_generates_select_widget(self):
        """A TextField with choices uses a Select widget."""
        f = models.TextField(choices=[('A', 'A'), ('B', 'B')])
        self.assertIsInstance(f.formfield().widget, forms.Select)

    def test_to_python(self):
        """TextField.to_python() should return a string."""
        f = models.TextField()
        self.assertEqual(f.to_python(1), '1')

    def test_lookup_integer_in_textfield(self):
        self.assertEqual(Post.objects.filter(body=24).count(), 0)

    @skipIf(connection.vendor == 'mysql', 'Running on MySQL requires utf8mb4 encoding (#18392)')
    def test_emoji(self):
        p = Post.objects.create(title='Whatever', body='Smile 😀.')
        p.refresh_from_db()
        self.assertEqual(p.body, 'Smile 😀.')


class TestMethods(SimpleTestCase):
    def test_deconstruct(self):
        field = models.TextField()
        *_, kwargs = field.deconstruct()
        self.assertEqual(kwargs, {})
        field = models.TextField(db_collation='utf8_esperanto_ci')
        *_, kwargs = field.deconstruct()
        self.assertEqual(kwargs, {'db_collation': 'utf8_esperanto_ci'})