Pillow/Tests/test_features.py

import io
import unittest

from PIL import features

from .helper import PillowTestCase

try:
    from PIL import _webp

    HAVE_WEBP = True
except ImportError:
    HAVE_WEBP = False


class TestFeatures(PillowTestCase):
    def test_check(self):
        # Check the correctness of the convenience function
        for module in features.modules:
            self.assertEqual(features.check_module(module), features.check(module))
        for codec in features.codecs:
            self.assertEqual(features.check_codec(codec), features.check(codec))
        for feature in features.features:
            self.assertEqual(features.check_feature(feature), features.check(feature))

    @unittest.skipUnless(HAVE_WEBP, "WebP not available")
    def test_webp_transparency(self):
        self.assertEqual(
            features.check("transp_webp"), not _webp.WebPDecoderBuggyAlpha()
        )
        self.assertEqual(features.check("transp_webp"), _webp.HAVE_TRANSPARENCY)

    @unittest.skipUnless(HAVE_WEBP, "WebP not available")
    def test_webp_mux(self):
        self.assertEqual(features.check("webp_mux"), _webp.HAVE_WEBPMUX)

    @unittest.skipUnless(HAVE_WEBP, "WebP not available")
    def test_webp_anim(self):
        self.assertEqual(features.check("webp_anim"), _webp.HAVE_WEBPANIM)

    def test_check_modules(self):
        for feature in features.modules:
            self.assertIn(features.check_module(feature), [True, False])
        for feature in features.codecs:
            self.assertIn(features.check_codec(feature), [True, False])

    def test_supported_modules(self):
        self.assertIsInstance(features.get_supported_modules(), list)
        self.assertIsInstance(features.get_supported_codecs(), list)
        self.assertIsInstance(features.get_supported_features(), list)
        self.assertIsInstance(features.get_supported(), list)

    def test_unsupported_codec(self):
        # Arrange
        codec = "unsupported_codec"
        # Act / Assert
        self.assertRaises(ValueError, features.check_codec, codec)

    def test_unsupported_module(self):
        # Arrange
        module = "unsupported_module"
        # Act / Assert
        self.assertRaises(ValueError, features.check_module, module)

    def test_pilinfo(self):
        buf = io.StringIO()
        features.pilinfo(buf)
        out = buf.getvalue()
        lines = out.splitlines()
        self.assertEqual(lines[0], "-" * 68)
        self.assertTrue(lines[1].startswith("Pillow "))
        self.assertTrue(lines[2].startswith("Python "))
        lines = lines[3:]
        while lines[0].startswith("    "):
            lines = lines[1:]
        self.assertEqual(lines[0], "-" * 68)
        self.assertTrue(lines[1].startswith("Python modules loaded from "))
        self.assertTrue(lines[2].startswith("Binary modules loaded from "))
        self.assertEqual(lines[3], "-" * 68)
        jpeg = (
            "\n"
            + "-" * 68
            + "\n"
            + "JPEG image/jpeg\n"
            + "Extensions: .jfif, .jpe, .jpeg, .jpg\n"
            + "Features: open, save\n"
            + "-" * 68
            + "\n"
        )
        self.assertIn(jpeg, out)