Invalidation fixes to Julia base are currently not tested. For example:

• fix invalidations from loading Static.jl #46761
• Fixed inference on String and Symbol causing invalidations in show.jl #44091
• Fix ~370 invalidations from Expr(:ncat, ...) pretty-printing #41877

This is asking for double work in the long run. Would it be possible to add something like SnoopCompileCore.@snoopr to Julia base? This would make it easier to add a tests. For example, #46481 fixes invalidations caused by inserting:

Base.:(!)(::True) = False()

With @snoopr defined as

https://github.com/timholy/SnoopCompile.jl/blob/f4d9a7b57a82c1bdb34579f255d3cf4abcc10b92/SnoopCompileCore/src/snoopr.jl#L26-L35

the method insertion could be tested with:

@test isempty(@snoopr Base.:(!)(::True) = False())

cc: @timholy, @ranocha