Fix most violations of new CA1859 #80335
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Tagging subscribers to this area: @dotnet/area-meta Issue DetailsThe analyzer recommends replacing uses of types with other types that could reduce overheads (e.g.
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Wow, that's a lot of stuff. CA1859 currently only recommends changing the signature of private methods and fields, the idea being that the changes are completely local to a given type. Do you think it would be useful to extend the analysis to internal symbols too, at least optionally? I bet that would raise another crop of these recommendations. Another thing I'd like to add in the analyzer is a basic understanding of collections. So if you have an |
The analyzer recommends replacing uses of types with other types that could reduce overheads (e.g. `List<T>` instead of `IList<T>`). This fixes most of the violations we currently have of the rule, but it doesn't enable it yet because there are too many false positives; fixes for those are in-flight. Some of these replacements won't help with perf (e.g. using `ArgumentException` instead of `Exception` as the return type of a throw helper create method), but there's little harm to them, and some of them do avoid overheads like allocation (e.g. foreach'ing something typed as `Dictionary<>` instead of `IDictionary<>` will avoid an enumerator allocation, accessing `Count` on a `List<T>` instead of `IList<T>` will avoid an interface dispatch, etc.)
Can you share an example?
Yeah, I think that would be useful, at least for some of the most common, like IEnumerable and List. |
src/libraries/System.Linq.Expressions/src/System/Linq/Expressions/Error.cs
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src/libraries/System.Net.HttpListener/src/System/Net/Windows/HttpRequestStream.Windows.cs
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...m.Security.Cryptography/src/System/Security/Cryptography/X509Certificates/X509Pal.OpenSsl.cs
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Be gone Peanut Butter! |
The analyzer recommends replacing uses of types with other types that could reduce overheads (e.g.
List<T>instead ofIList<T>). This fixes most of the violations we currently have of the rule, but it doesn't enable it yet because there are too many false positives; fixes for those are in-flight. Some of these replacements won't help with perf (e.g. usingArgumentExceptioninstead ofExceptionas the return type of a throw helper create method), but there's little harm to them, and some of them do avoid overheads like allocation (e.g. foreach'ing something typed asDictionary<>instead ofIDictionary<>will avoid an enumerator allocation, accessingCounton aList<T>instead ofIList<T>will avoid an interface dispatch, etc.)cc: @buyaa-n, @geeknoid