vm: enhance cached data handling for empty functions and add validation tests

[gurgunday]

Fixes #56366

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.

Project coverage is 88.54%. Comparing base (35742a2) to head (e1b97b8).
Report is 20 commits behind head on main.

Files with missing lines	Patch %	Lines
src/node_contextify.cc	83.33%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #56442      +/-   ##
==========================================
- Coverage   88.54%   88.54%   -0.01%     
==========================================
  Files         657      657              
  Lines      190742   190744       +2     
  Branches    36606    36617      +11     
==========================================
- Hits       168901   168893       -8     
- Misses      15027    15029       +2     
- Partials     6814     6822       +8     

Files with missing lines	Coverage Δ
src/node_contextify.cc	81.41% <83.33%> (+0.04%)	⬆️

... and 37 files with indirect coverage changes

[legendecas]

The issue is that the code cache of vm.Script and vm.compileFunction can not be interchanged. I think this is rather a V8 issue that it didn't reject the incorrect code cache.

[legendecas]

There is no JavaScript execution in this scope and this TryCacheScope is redundant.

[legendecas]

I don't think this guard is the correct solution. When produceCachedData is true, a new cached data should always be returned regardless of whether the old one is consumed or not.

[legendecas]

The fn here is always not empty.

[gurgunday]

The issue is that the code cache of vm.Script and vm.compileFunction can not be interchanged. I think this is rather a V8 issue that it didn't reject the incorrect code cache.

I see, so you say it's better to signal this to the V8 team and wait? This also fixes it

[legendecas]

v8/v8@96ee9bb should fix the issue.