[SDK] Fix include instrumentation scope attributes in equal method

[dbarker]

Fixes #3208

Changes

This PR updates the GetTracer, GetMeter, and GetLogger methods to include instrumentation scope attributes in the equality check before returning a cached instance.

• Adds AttributeEqualToVisitor to sdk/common/attribute_utils.h that compares an OwnedAttributeValue to a AttributeValue
• Adds EqualTo method to the AttributeMap class to support checking equality with a KeyValueIterable
• Updates the InstrumenationScope::equal method to accept attributes and evaluate them
• Updates tests for Get<Logger,Tracer,Meter> methods to check for instance uniqueness based on the OTEL spec.
• Updates tests for InstrumentationScope and AttributeMap to cover the equal and EqualTo methods

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

[netlify]

✅ Deploy Preview for opentelemetry-cpp-api-docs canceled.

Name	Link
🔨 Latest commit	5ae1b09
🔍 Latest deploy log	https://app.netlify.com/sites/opentelemetry-cpp-api-docs/deploys/67630b1f3a301300088b21f4

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.16%. Comparing base (0b94d71) to head (5ae1b09).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3214      +/-   ##
==========================================
+ Coverage   87.82%   88.16%   +0.35%     
==========================================
  Files         195      198       +3     
  Lines        6154     6224      +70     
==========================================
+ Hits         5404     5487      +83     
+ Misses        750      737      -13     

Files with missing lines	Coverage Δ
...include/opentelemetry/sdk/common/attribute_utils.h	93.69% <100.00%> (+2.78%)	⬆️
...y/sdk/instrumentationscope/instrumentation_scope.h	100.00% <100.00%> (ø)
sdk/src/logs/logger_provider.cc	90.91% <100.00%> (ø)
sdk/src/metrics/meter_provider.cc	87.18% <100.00%> (ø)
sdk/src/trace/tracer_provider.cc	89.37% <100.00%> (ø)

... and 10 files with indirect coverage changes

[dbarker]

CI has passed. Ready for review.

[owent]

Do you think we can use this->find(kv.first) here for better performance?

[dbarker]

It seems we have to start the search from the KeyValueIterable::ForEachKeyValue method and it provides a nostd::string_view key while the key type of the map is std::string. So we either have to iterate directly like this or create a temp string every time as in auto iter = this->find(std::string(key)). I chose the first option since it I've heard it could be faster than find for small maps :) and I didn't feel like string allocation (and its potential to throw) was ideal. I could profile both options if it seems worth it.

C++20 gives the "Heterogeneous comparison lookup" version of the std::unordered_map::find method of unordered_map which is really what we need here. Here's a neat example https://godbolt.org/z/Yqsx4rsY1

[marcalff]

Thanks for the details. Looks ok to me as is.

[marcalff]

LGTM, thanks for the fix.

Very well done, and with good test coverage.

[dbarker]

I realized i missed a comment and update to operator== of the InstrumentationScope. Will push a commit shortly.

[dbarker]

I realized i missed a comment and update to operator== of the InstrumentationScope. Will push a commit shortly.

Done. CI passed.