SA1137 is not raised

[Mivee]

Issue URL: #3904

Collectionexpressions are detected as variable declarations and not as InitializerExpression.

Previously they where checked based on the declaration itself (so we only have 1 Item e.g. var myVariable = [1,2,3]) . Now, for collection initializations we get the SyntaxNode from the variable and then validate each item of the collection on its own.

Since this is my first open source contribution feedback is very welcome.

I also found 2 points where I'm not sure how to proceed with:

• Microsoft.CodeAnalysis.CSharp is installed with V.1.2.1 @Stylecop.Analyzers. V.4.7.0 introduced the CollectionExpressionSyntax that would simply my IsCollectionExpression() to just a type check basiclly. Also the "workaround" with that id could be removed so imo it would be way cleaner, due to beeing 3 Major Versions behind i didnt wanted to update, since i basiclly dont know the project and also what could be affected by that upgrade.
• locally StyleCop.Analyzers.Test.CSharp8.SpacingRules.SA1009CSharp8UnitTests.TestMissingTokenAsync failed due to having a different Windows language. A possible solution could be https://stackoverflow.com/questions/5793000/is-this-a-good-approach-for-temporarily-changing-the-current-threads-culture

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.44%. Comparing base (f5843ae) to head (d22f8a0).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3910   +/-   ##
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  Coverage   97.44%   97.44%           
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  Files         926      932    +6     
  Lines      110283   110380   +97     
  Branches     3319     3320    +1     
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+ Hits       107467   107564   +97     
  Misses       1847     1847           
  Partials      969      969