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HarfBuzz language_from_string Python introspection method doesn't accept str

I'm just getting started with HarfBuzz, and have switched to using the GObject Introspection interface to explore its API. Everything has been easy so far, but I'm a bit confused with language_from_string, which has the following docstring:

language_from_string(str:list) -> HarfBuzz.language_t

i.e. in IPython, I do:

from gi.repository import HarfBuzz

?HarfBuzz.language_from_string

in vanilla Python, you can replace the last line with: print(HarfBuzz.language_from_string.__doc__) (or similar)

if I call this method with a string, e.g:

HarfBuzz.language_from_string('en')

I get

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Item 0: Must be number, not str

back, while if I convert to a list of code points first:

en = HarfBuzz.language_from_string(list(map(ord, 'en')))

the error goes away, and I get something useful back. e.g. I can do:

HarfBuzz.language_to_string(en)

and I get the expected en back, in a string.

HarfBuzz Issue #91 is about this method, but doesn't seem to be relevant.

Solution

  • You have to call it like HarfBuzz.language_from_string(b'en') (string but prefixed with b) in python3 as strings are not just sequence of bytes anymore in py3 unlike py2.

    Do you know any gi API that gets an actual python representation of string in python3? If so let me know otherwise this is expected from HarfBuzz side.