Fix build break

[kg]

Draft PR because I'm not convinced this is the right fix.

[ghost]

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Issue Details

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null

Author:	kg
Assignees:	kg
Labels:	area-System.Text.Json
Milestone:	-

[jkotas]

I think these tests wants to really test for default. This build break should be fixed by pragma warning disable.

[kg]

Yeah that's my thinking too. I wanted to see if there are more breaks after these ones are fixed.

[buyaa-n]

Ah, the analyzer should be disabled for test projects, could you please add below rows here:

runtime/eng/CodeAnalysis.test.globalconfig

Lines 675 to 677 in b5b290f

	# CA2261: Do not use ConfigureAwaitOptions.SuppressThrowing with Task<TResult>
	dotnet_diagnostic.CA2261.severity = none

# CA2265: Do not compare Span<T> to 'null' or 'default'
dotnet_diagnostic.CA2265.severity = none

[buyaa-n]

I see the analyzer updated reverted, this can be added later when analyzer updated

[vcsjones]

There are still more build issues this PR does not address, like in src/libraries/System.Runtime/tests/System.Runtime.Tests/:

/Users/vcsjones/Projects/runtime/src/libraries/System.Runtime/tests/System.Runtime.Tests/System/StringTests.cs(1085,25): error CA2265: Comparing a span to 'default' might not do what you intended, make the code more explicit by checking 'IsEmpty' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca2265) [/Users/vcsjones/Projects/runtime/src/libraries/System.Runtime/tests/System.Runtime.Tests/System.Runtime.Tests.csproj::TargetFramework=net9.0-unix]