fix(propagator-ot-trace): read sampled flag correctly from span context

[basti1302]

Which problem is this PR solving?

Fixes the way the sampled flag is read from the span context. The way it
is currently read will break when more flags are introduced. This is even
mentioned explicitly in the
specification.

Short description of the changes

• check the flag bit independently instead of comparing the whole flags byte value with the SAMPLED_FLAG constant.
• add a unit test that show cases the issue (and breaks without the change in production code)

Checklist

• Ran npm run test for the edited package(s) on the latest commit if applicable.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: basti1302 / name: Bastian Krol (76fa970)

[rauno56]

Good catch! Thanks.

[basti1302]

For the record, I am currently working with the CCLA managers at my org to get my CLA in place.

[codecov]

Codecov Report

Merging #1077 (1e8558a) into main (57cedc5) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1077   +/-   ##
=======================================
  Coverage   95.91%   95.91%           
=======================================
  Files          13       13           
  Lines         856      857    +1     
  Branches      178      179    +1     
=======================================
+ Hits          821      822    +1     
  Misses         35       35           

Impacted Files	Coverage Δ
...metry-propagator-ot-trace/src/OTTracePropagator.ts	95.91% <100.00%> (+0.08%)	⬆️

[basti1302]

I have the CLA in place now. It shows up okay on #1081, but not here. If I go through the EasyCLA process again for this PR (clicking on the links in the EasyCLA bot message in this PR), it ends with this

... but after that, the check still shows up as failed.

I guess EasyCLA does not handle multiple simultaneous PRs from a first time contributor all that well? Should I just close this PR and open it again? Or use the support ticket link? ("For further assistance with EasyCLA, please submit a support request ticket.

[Flarna]

@basti1302 Try to push a commit, maybe this retriggers the check here.

[basti1302]

@basti1302 Try to push a commit, maybe this retriggers the check here.

It did! Thanks 👍 CLA shows up as "covered" now.

[basti1302]

I think this change is ready to be merged.

[Flarna]

@basti1302 it requires a rebase/merge from main.
I have no rights to do this on your fork, most likely because its owned by an org. In that case the "allow maintainer edits" doesn't work.

[basti1302]

@basti1302 it requires a rebase/merge from main. I have no rights to do this on your fork, most likely because its owned by an org. In that case the "allow maintainer edits" doesn't work.

I had rebased this branch earlier today, but of course after the merge of #1078 it now needed yet another rebase, which I have performed just now.