Fix errors on serializaiton of an image created by AOSP contacts

[dreua]

Not sure if I understood everything correctly here but this works for me. Might update this PR after some more testing.

[dreua]

I don't think there is any test file with a "PHOTO" in it, is it?

[dreua]

Here is the stacktrace without the patch:

Traceback (most recent call last):
  File "/usr/lib64/python3.12/runpy.py", line 198, in _run_module_as_main
    return _run_code(code, main_globals, None,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.12/runpy.py", line 88, in _run_code
    exec(code, run_globals)
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/launcher/../../debugpy/__main__.py", line 39, in <module>
    cli.main()
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/launcher/../../debugpy/../debugpy/server/cli.py", line 430, in main
    run()
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/launcher/../../debugpy/../debugpy/server/cli.py", line 284, in run_file
    runpy.run_path(target, run_name="__main__")
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_runpy.py", line 321, in run_path
    return _run_module_code(code, init_globals, run_name,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_runpy.py", line 135, in _run_module_code
    _run_code(code, mod_globals, init_globals,
  File "/home/da/.vscode/extensions/ms-python.debugpy-2024.6.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_runpy.py", line 124, in _run_code
    exec(code, run_globals)

[My code just loading a contact from file with an attached photo and then calling serialize on it.]

  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 254, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/behavior.py", line 166, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 1007, in defaultSerialize
    child.serialize(outbuf, lineLength, validate=False)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 254, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/vcard.py", line 231, in serialize
    VCardTextBehavior.serialize(obj, buf, lineLength, validate, *args, **kwargs)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/behavior.py", line 166, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 1015, in defaultSerialize
    obj.behavior.encode(obj)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/vcard.py", line 155, in encode
    line.value = backslashEscape(line.value)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 1219, in backslashEscape
    s = s.replace("\\", "\\\\").replace(";", "\\;").replace(",", "\\,")
        ^^^^^^^^^^^^^^^^^^^^^^^
TypeError: a bytes-like object is required, not 'str'

[dreua]

In a first step I tried to just ignore byte objects in "backslashEscape" but it still failed when serializing:

Traceback (most recent call last):
[...]
    pprint(vo.serialize())
           ^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 254, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/behavior.py", line 166, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 1007, in defaultSerialize
    child.serialize(outbuf, lineLength, validate=False)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 254, in serialize
    return behavior.serialize(self, buf, lineLength, validate, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/vcard.py", line 231, in serialize
    VCardTextBehavior.serialize(obj, buf, lineLength, validate, *args, **kwargs)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/behavior.py", line 166, in serialize
    out = base.defaultSerialize(transformed, buf, lineLength)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/da/.local/lib/python3.12/site-packages/vobject/base.py", line 1034, in defaultSerialize
    obj.behavior.decode(obj)
  File "/home/da/.local/lib/python3.12/site-packages/vobject/vcard.py", line 135, in decode
    line.value = codecs.decode(line.value, "base64")
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.12/encodings/base64_codec.py", line 19, in base64_decode
    return (base64.decodebytes(input), len(input))
            ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.12/base64.py", line 554, in decodebytes
    return binascii.a2b_base64(s)
           ^^^^^^^^^^^^^^^^^^^^^^
binascii.Error: Invalid base64-encoded string: number of data characters (445) cannot be 1 more than a multiple of 4
decoding with 'base64' codec failed

[dreua]

Rebased on top of testfile and test

[da4089]

Thanks for the PR!