Complete Definition of Each Supported Script

[Richard Wordingham via Unicode]

I just found this assertion in https://en.wikipedia.org/wiki/Uniscribe:

"Microsoft worked with the Unicode Technical Committee to make shaping
requirements available in a machine readable format, so a complete
definition of each supported script will be included in the Unicode
standard and updating or adding new scripts will be significantly
simplified."

It was added on 14 August 2016.

Apart from the holding of discussions and the consequences for
Uniscribe/DirectWrite, is this true or is someone adding two and two
together and making five?

1. In particular, is this anything more than reading too much into the
General_Category, Indic_syllabic_Category and
Indic_Positional_Category?  They could only work if the regular
expressions in the documentation of the Universal Script Engine were
correct (we know they aren't), and there are many shaping requirements
that font developers have to discover from other sources.

If there is more to it:

2. Are there "shaping requirements available in machine readable
format", and if so, how can one obtain them?

3. When will these "complete definition[s] of each supporting script
[...] be included in the Unicode standard"?  How will they be checked?
(There is a very good chance that many of them would be wrong.)


Richard.