test_file_fits.py

from io import BytesIO

import pytest

from PIL import FitsImagePlugin, FitsStubImagePlugin, Image

from .helper import assert_image_equal, hopper

TEST_FILE = "Tests/images/hopper.fits"


def test_open():
    # Act
    with Image.open(TEST_FILE) as im:

        # Assert
        assert im.format == "FITS"
        assert im.size == (128, 128)
        assert im.mode == "L"

        assert_image_equal(im, hopper("L"))


def test_invalid_file():
    # Arrange
    invalid_file = "Tests/images/flower.jpg"

    # Act / Assert
    with pytest.raises(SyntaxError):
        FitsImagePlugin.FitsImageFile(invalid_file)


def test_truncated_fits():
    # No END to headers
    image_data = b"SIMPLE  =                    T" + b" " * 50 + b"TRUNCATE"
    with pytest.raises(OSError):
        FitsImagePlugin.FitsImageFile(BytesIO(image_data))


def test_naxis_zero():
    # This test image has been manually hexedited
    # to set the number of data axes to zero
    with pytest.raises(ValueError):
        with Image.open("Tests/images/hopper_naxis_zero.fits"):
            pass


def test_stub_deprecated():
    class Handler:
        opened = False
        loaded = False

        def open(self, im):
            self.opened = True

        def load(self, im):
            self.loaded = True
            return Image.new("RGB", (1, 1))

    handler = Handler()
    with pytest.warns(DeprecationWarning):
        FitsStubImagePlugin.register_handler(handler)

    with Image.open(TEST_FILE) as im:
        assert im.format == "FITS"
        assert im.size == (128, 128)
        assert im.mode == "L"

        assert handler.opened
        assert not handler.loaded

        im.load()
        assert handler.loaded

    FitsStubImagePlugin._handler = None
    Image.register_open(
        FitsImagePlugin.FitsImageFile.format,
        FitsImagePlugin.FitsImageFile,
        FitsImagePlugin._accept,
    )