builtin,vm: add implementation for builtin hex function

[sbinet]

No description provided.

[codecov-io]

Codecov Report

Merging #123 into master will decrease coverage by 0.16%.
The diff coverage is 3.44%.

@@            Coverage Diff             @@
##           master     #123      +/-   ##
==========================================
- Coverage   72.74%   72.57%   -0.17%     
==========================================
  Files          60       60              
  Lines       11970    11999      +29     
==========================================
+ Hits         8707     8708       +1     
- Misses       2729     2757      +28     
  Partials      534      534

Impacted Files	Coverage Δ
builtin/builtin.go	74.07% <3.44%> (-3.46%)	⬇️

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[sbinet]

does anybody understand why e.g. builtin_isinstance and builtin_hex are marked as "not covered" while e.g. builtin_sorted is?

For the life of me, I just don't understand.

[ncw]

Codecov seems to do mad things sometimes! Did you force push your branch? I think that makes it worse sometimes.

I wonder if there is a retry button for codecov?

[sbinet]

no, I didn't force push. (at least, not for this PR :P)
and actually running go test -cover also shows the same behaviour wrt builtin_hex and builtin_sorted.

[ncw]

Very strange. I can't see anything wrong with your code. Might be worth trying with different go versions to see if it is a go bug.

[corona10]

lgtm

[sbinet]

ok. figured it out.

the tests (for builtin_hex and builtin_isinstance) were in the wrong location (and actually badly written) :)

[sbinet]

@ncw PTAL

[ncw]

Look great now :-)

I'll merge it