How to use the mutagen.mp4.Atom.render function in mutagen

def test_covr_blank_format(self):
        data = Atom.render(
            b"data", b"\x00\x00\x00\x00" + b"\x00" * 4 + b"whee")
        covr = Atom.render(b"covr", data)
        tags = self.wrap_ilst(covr)
        self.failUnlessEqual(
            MP4Cover.FORMAT_JPEG, tags["covr"][0].imageformat)

def test_strips_bad_unknown_types(self):
        data = Atom.render(b"datA", b"\x00" * 8 + b"whee")
        foob = Atom.render(b"foob", data)
        tags = self.wrap_ilst(foob)
        self.failIf(tags)

def test_mdhd_version_1(self, soun=b"soun"):
        mdhd = Atom.render(b"mdhd", (b"\x01\x00\x00\x00" + b"\x00" * 16 +
                                     b"\x00\x00\x00\x02" +  # 2 Hz
                                     b"\x00\x00\x00\x00\x00\x00\x00\x10"))
        hdlr = Atom.render(b"hdlr", b"\x00" * 8 + soun)
        mdia = Atom.render(b"mdia", mdhd + hdlr)
        trak = Atom.render(b"trak", mdia)
        moov = Atom.render(b"moov", trak)
        fileobj = BytesIO(moov)
        atoms = Atoms(fileobj)
        info = MP4Info(atoms, fileobj)
        self.failUnlessEqual(info.length, 8)

def wrap_ilst(self, data):
        ilst = Atom.render(b"ilst", data)
        meta = Atom.render(b"meta", b"\x00" * 4 + ilst)
        data = Atom.render(b"moov", Atom.render(b"udta", meta))
        fileobj = BytesIO(data)
        return MP4Tags(Atoms(fileobj), fileobj)

def test_multiple_tracks(self):
        hdlr = Atom.render(b"hdlr", b"\x00" * 8 + b"whee")
        mdia = Atom.render(b"mdia", hdlr)
        trak1 = Atom.render(b"trak", mdia)
        mdhd = Atom.render(b"mdhd", (b"\x01\x00\x00\x00" + b"\x00" * 16 +
                                     b"\x00\x00\x00\x02" + # 2 Hz
                                     b"\x00\x00\x00\x00\x00\x00\x00\x10"))
        hdlr = Atom.render(b"hdlr", b"\x00" * 8 + b"soun")
        mdia = Atom.render(b"mdia", mdhd + hdlr)
        trak2 = Atom.render(b"trak", mdia)
        moov = Atom.render(b"moov", trak1 + trak2)
        fileobj = cBytesIO(moov)
        atoms = Atoms(fileobj)
        info = MP4Info(atoms, fileobj)
        self.failUnlessEqual(info.length, 8)
add(TMP4Info)

def test_genre_too_big(self):
        data = Atom.render(b"data", b"\x00" * 8 + b"\x01\x00")
        genre = Atom.render(b"gnre", data)
        tags = self.wrap_ilst(genre)
        self.failIf(b"gnre" in tags)
        self.failIf(b"\xa9gen" in tags)

def test_genre_too_big(self):
        data = Atom.render(b"data", b"\x00" * 8 + b"\x01\x00")
        genre = Atom.render(b"gnre", data)
        tags = self.wrap_ilst(genre)
        self.failIf("gnre" in tags)
        self.failIf("\xa9gen" in tags)

def test_render_too_big(self):
        class TooBig(bytes):
            def __len__(self):
                return 1 << 32
        data = TooBig(b"test")
        try:
            len(data)
        except OverflowError:
            # Py_ssize_t is still only 32 bits on this system.
            self.failUnlessRaises(OverflowError, Atom.render, b"data", data)
        else:
            data = Atom.render(b"data", data)
            self.failUnlessEqual(len(data), 4 + 4 + 8 + 4)

def test_render_too_big(self):
        class TooBig(bytes):
            def __len__(self):
                return 1 << 32
        data = TooBig(b"test")
        try: len(data)
        except OverflowError:
            # Py_ssize_t is still only 32 bits on this system.
            self.failUnlessRaises(OverflowError, Atom.render, b"data", data)
        else:
            data = Atom.render(b"data", data)
            self.failUnlessEqual(len(data), 4 + 4 + 8 + 4)

def __render_data(self, key, flags, value):
        return Atom.render(key, b''.join(
            Atom.render(b"data", struct.pack(">2I", flags, 0) + data)
            for data in value))