Testing lots of Texinfo files

[Gavin Smith]

Does anybody know of a way to test lots of Texinfo files, e.g. 
everything linked from https://www.gnu.org/manual/? What I'd like to do 
is test all of these files with the Texinfo XS parser enabled and also 
with it disabled, and see what if any differences there are.  This is 
important because the XS parser is now enabled by default in the 
development version, and has been since after the last release (a year 
ago).  This produces a speedup of approximately 50%, on top of the speed 
gains from the other (simpler) XS modules that are already enabled by 
default.  This would be the big highlight of the next release, along 
with the Texinfo JS Interface.

I remember the last time that a pretest release was made with the XS 
parser enabled, it broke lots of things on the Debian buildfarm.