bug#62086: 29.0.60; ruby-ts-mode regressions

[Dmitry Gutov]

On 12/04/2023 18:31, Dmitry Gutov wrote:
> On 12/04/2023 10:05, Yuan Fu wrote:
> > Actually, would it make sense to define sexp as “anything but some 
> > very small punctuation and delimiters”?
>
> Pretty much. If I understood you correctly.
>
> E.g. in ruby-ts-mode identifiers and numbers are also sexps.

Allow me to update that.

From the previous threads, for ruby-ts-mode at least, we seem to have 
concluded that it's best to treat those nodes as sexps which have 
visible boundaries that are visible and don't overlay exactly the 
boundaries of the contained nodes.

For example, we now exclude statement nodes and binary expression nodes 
because both make forward/backward-sexp less obvious and predictable: 
you move point to the beginning of 'a + b', press C-M-f, and if the jump 
happens over the whole expression, this is just as likely to mismatch 
the user's intention (which might have wanted to only jump over 'a'). So 
these are the node we rule out.

The easiest choice would be to go back to treating only 
braces/brackets/parens are sexp delimiters, but in Ruby, at least, we 
have lots of constructs that are delimited with keywords (such as 'if', 
'def', 'end'), so that doesn't work. Maybe it'll work better in C/C++, 
where you mostly need to be able to differentiate between different 
types of angle brackets.