Remove RunSerial from tests

[brianpopow]

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Description

This PR removes [Collection("RunSerial")] from the decoding/encoding tests, which was meant as a workaround for the sporadic OOM failures. Hopefully with #1730 this should no longer be necessary.

[codecov]

Codecov Report

Merging #1885 (edf7014) into master (3730a02) will decrease coverage by 0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #1885   +/-   ##
======================================
- Coverage      87%     87%   -1%     
======================================
  Files         959     959           
  Lines       50392   50392           
  Branches     6258    6258           
======================================
- Hits        44113   44109    -4     
- Misses       5246    5248    +2     
- Partials     1033    1035    +2     

Flag	Coverage Δ
unittests	87% <ø> (-1%)	⬇️

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Impacted Files	Coverage Δ
...emory/DiscontiguousBuffers/MemoryGroup{T}.Owned.cs	86% <0%> (-5%)	⬇️

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[brianpopow]

No OOM so far, i will re-run the tests a few more times, just to make sure.

[brianpopow]

I have not seen any OOM so far, but similar to #1886, i have seen 3 times out of 6 runs the same failing test om macos:

AllocateMemoryGroup_Finalization_ReturnsToPool(length: 1200) [FAIL]
[xUnit.net 00:02:15.34]     AllocateMemoryGroup_Finalization_ReturnsToPool(length: 600) [FAIL]
  Failed AllocateMemoryGroup_Finalization_ReturnsToPool(length: 1200) [286 ms]
  Error Message:
   Microsoft.DotNet.RemoteExecutor.RemoteExecutionException : Remote process failed with an unhandled exception.
  Stack Trace:
  
Child exception:
  Xunit.Sdk.EqualException: Assert.Equal() Failure
Expected: 42
Actual:   0
   at SixLabors.ImageSharp.Tests.Memory.Allocators.UniformUnmanagedPoolMemoryAllocatorTests.AllocateGroupAndForget(UniformUnmanagedMemoryPoolMemoryAllocator allocator, Int32 length, Boolean check) in /Users/runner/work/ImageSharp/ImageSharp/tests/ImageSharp.Tests/Memory/Allocators/UniformUnmanagedPoolMemoryAllocatorTests.cs:line 299
   at SixLabors.ImageSharp.Tests.Memory.Allocators.UniformUnmanagedPoolMemoryAllocatorTests.<AllocateMemoryGroup_Finalization_ReturnsToPool>g__RunTest|12_0(String lengthStr) in /Users/runner/work/ImageSharp/ImageSharp/tests/ImageSharp.Tests/Memory/Allocators/UniformUnmanagedPoolMemoryAllocatorTests.cs:line 283

Child process:
  SixLabors.ImageSharp.Tests, Version=1.0.0.0, Culture=neutral, PublicKeyToken=d998eea7b14cab13 SixLabors.ImageSharp.Tests.Memory.Allocators.UniformUnmanagedPoolMemoryAllocatorTests Void <AllocateMemoryGroup_Finalization_ReturnsToPool>g__RunTest|12_0(System.String)

Child arguments:
  1200

  Failed AllocateMemoryGroup_Finalization_ReturnsToPool(length: 600) [538 ms]
  Error Message:
   Microsoft.DotNet.RemoteExecutor.RemoteExecutionException : Remote process failed with an unhandled exception.
  Stack Trace:
  
Child exception:
  Xunit.Sdk.EqualException: Assert.Equal() Failure
Expected: 42
Actual:   0
   at SixLabors.ImageSharp.Tests.Memory.Allocators.UniformUnmanagedPoolMemoryAllocatorTests.<AllocateMemoryGroup_Finalization_ReturnsToPool>g__RunTest|12_0(String lengthStr) in /Users/runner/work/ImageSharp/ImageSharp/tests/ImageSharp.Tests/Memory/Allocators/UniformUnmanagedPoolMemoryAllocatorTests.cs:line 290

[antonfirsov]

Macos only? If yes let's just disable them with a skip condition on macos, or an [ActiveIssue(...)] aftrr opening an issue.

[JimBobSquarePants]

I wonder what the specs of the macOS image are? Could it be hitting the high memory cleanup issue my machine was. I’ll try running that test locally later.

[brianpopow]

I have added [ActiveIssue("https://github.com/SixLabors/ImageSharp/issues/1887", TestPlatforms.OSX)] to the failing test.

As far as i understand this attribute, this will skip the test only on OSX (correct me, if i am wrong)

[JimBobSquarePants]

@brianpopow Yep, that's correct.
https://github.com/dotnet/runtime/blob/main/docs/workflow/testing/libraries/filtering-tests.md#activeissueattribute