django/tests/forms_tests/widget_tests/test_fileinput.py

from django.core.files.uploadedfile import SimpleUploadedFile
from django.forms import FileField, FileInput, Form
from django.utils.datastructures import MultiValueDict

from .base import WidgetTest


class FileInputTest(WidgetTest):
    widget = FileInput()

    def test_render(self):
        """
        FileInput widgets never render the value attribute. The old value
        isn't useful if a form is updated or an error occurred.
        """
        self.check_html(
            self.widget,
            "email",
            "test@example.com",
            html='<input type="file" name="email">',
        )
        self.check_html(
            self.widget, "email", "", html='<input type="file" name="email">'
        )
        self.check_html(
            self.widget, "email", None, html='<input type="file" name="email">'
        )

    def test_value_omitted_from_data(self):
        self.assertIs(self.widget.value_omitted_from_data({}, {}, "field"), True)
        self.assertIs(
            self.widget.value_omitted_from_data({}, {"field": "value"}, "field"), False
        )

    def test_use_required_attribute(self):
        # False when initial data exists. The file input is left blank by the
        # user to keep the existing, initial value.
        self.assertIs(self.widget.use_required_attribute(None), True)
        self.assertIs(self.widget.use_required_attribute("resume.txt"), False)

    def test_fieldset(self):
        class TestForm(Form):
            template_name = "forms_tests/use_fieldset.html"
            field = FileField(widget=self.widget)

        form = TestForm()
        self.assertIs(self.widget.use_fieldset, False)
        self.assertHTMLEqual(
            '<div><label for="id_field">Field:</label><input id="id_field" '
            'name="field" required type="file"></div>',
            form.render(),
        )

    def test_multiple_error(self):
        msg = "FileInput doesn't support uploading multiple files."
        with self.assertRaisesMessage(ValueError, msg):
            FileInput(attrs={"multiple": True})

    def test_value_from_datadict_multiple(self):
        class MultipleFileInput(FileInput):
            allow_multiple_selected = True

        file_1 = SimpleUploadedFile("something1.txt", b"content 1")
        file_2 = SimpleUploadedFile("something2.txt", b"content 2")
        # Uploading multiple files is allowed.
        widget = MultipleFileInput(attrs={"multiple": True})
        value = widget.value_from_datadict(
            data={"name": "Test name"},
            files=MultiValueDict({"myfile": [file_1, file_2]}),
            name="myfile",
        )
        self.assertEqual(value, [file_1, file_2])
        # Uploading multiple files is not allowed.
        widget = FileInput()
        value = widget.value_from_datadict(
            data={"name": "Test name"},
            files=MultiValueDict({"myfile": [file_1, file_2]}),
            name="myfile",
        )
        self.assertEqual(value, file_2)

    def test_multiple_default(self):
        class MultipleFileInput(FileInput):
            allow_multiple_selected = True

        tests = [
            (None, True),
            ({"class": "myclass"}, True),
            ({"multiple": False}, False),
        ]
        for attrs, expected in tests:
            with self.subTest(attrs=attrs):
                widget = MultipleFileInput(attrs=attrs)
                self.assertIs(widget.attrs["multiple"], expected)