SFDUTF7 encoder/decoder library

FontForge's Spline Font Databases have a rather unusual encoding called "UTF-7", but which is incompatible with either the common meaning of this word or the IMAP meaning. It is instead its own encoding unrelated to either, which I have implemented for use in sfdnormalize and other projects.

Tests / source of truth

The ultimate source of truth for this library is the implementation as it appears in FontForge's sfd.c of SFDDumpUTF7Str and SFDReadUTF7Str.

The function utf7toutf8_copy has some involvment as well. There is no spec, if this library results in a string FontForge can decode transparently (not the same thing as "exactly the same string FontForge itself would produce"!) my implementation is right; if it doesn't then it's not, please open a bug! :-)

License

Copyright (c) 2014–2022

• sfdnormalize: Fredrick R. Brennan (@ctrlcctrlv)
• IMAPClient¹: Menno Finlay-Smits (@mjs), Carson Ip (GitHub @carsonip), Mathieu Agopian (@magopian), John Villalovos (@JohnVillalovos)

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¹ The version of IMAPClient this is based on is 6e6ec34b0e71975134d9492add22361ce4beb2a0: https://github.com/mjs/imapclient/blob/6e6ec34b0e71975134d9492add22361ce4beb2a0/imapclient/imap_utf7.py.