That requires to package a new lib: 'pp'.
Unfortunately, this package would need another new package,
'ppx_expect'.
In turn, that one needs another package 'ppx_inline_test'.
And for that, I would need another package, 'time_now'.
Which needs new packages for 'jane-street-headers' and 'jst-config'.
You'll be glad to know that the Jane Street headers seem to require
nothing new - but 'jst-config' does want a new package: 'ppx_assert'.
Finally, 'ppx_assert' would like a new package for 'ppx_cold' and the
trail seems to end at that point.
Do we have anything about any of those? Like experimental packages or
existing packages I didn't recognize as one of the above?
If nobody has a better idea, I'll enter the ITP-package-upload dance...