🦟 Bug fix

Follow up to https://github.com/gazebosim/sdformat/pull/858
Needed by https://github.com/gazebosim/gz-sim/pull/1404

Summary

Plugin's extraction operator was consuming the entire input stream, although it should only be taking the first <plugin> element.

This PR fixes the most basic use case, which requires the element to be exactly closed with </plugin>. I also didn't do a lot of sanity checking, like does it start with <plugin>, or is there a <plugin> nested inside another, etc. I feel like there must be a more reliable way of doing this, I'm all ears for ideas.

This operator is used on gz-sim to deserialize an sdf::Plugins object (i.e. std::vector<sdf::Plugin>), and the serialization is just concatenating them right now, using the VectorSerializer.

Checklist

[x] Signed all commits for DCO
[x] Added tests
[ ] Updated documentation (as needed)
[ ] Updated migration guide (as needed)
[ ] Consider updating Python bindings (if the library has them)
[x] codecheck passed (See contributing)
[x] All tests passed (See test coverage)
[x] While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

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May 18 '22 01:05 chapulina

Codecov Report

Merging #1021 (4f9b92a) into sdf12 (b59f6e1) will increase coverage by 0.02%. The diff coverage is 98.27%.

:exclamation: Current head 4f9b92a differs from pull request most recent head 6c2f54c. Consider uploading reports for the commit 6c2f54c to get more accurate results

@@            Coverage Diff             @@
##            sdf12    #1021      +/-   ##
==========================================
+ Coverage   91.28%   91.31%   +0.02%     
==========================================
  Files          80       80              
  Lines       13086    13127      +41     
==========================================
+ Hits        11946    11987      +41     
  Misses       1140     1140

Impacted Files	Coverage Δ
include/sdf/Plugin.hh	`100.00% <ø> (+6.25%)`	:arrow_up:
src/Utils.hh	`94.73% <ø> (ø)`
src/Plugin.cc	`99.19% <95.65%> (-0.81%)`	:arrow_down:
src/Utils.cc	`88.50% <100.00%> (+2.43%)`	:arrow_up: