[libraries] Update System.Runtime.Extensions tests for iOS,MacCatalyst,tvOS

[mdh1418]

Fixes #34030
Fixes #36896

Rerunning the test suite after removing SkipOnPlatform and ActiveIssue in #36896 before the latest edit, it was found that the only changes are that TestingCreateInstanceFromObjectHandle passes on iOS and tvOS, and that TestingCreateInstanceFromObjectHandleFullSignature no longer fails. The other tests still fail and the activeIssues/SkipOnPlatform stand.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[jkotas]

Do you expect that this test can be fixed to be valid on Catalyst? Catalyst is generally like iOS.

[akoeplinger]

Yeah Catalyst has the same behavior as iOS here. We can actually enable parts of the test since we just use a different value for SpecialFolder.Personal / SpecialFolder.MyDocuments. Will push to the PR.

[mdh1418]

Looking more closely, it looks like Environment.GetEnvironmentVariable("Home") is null or empty on iOSSimulator and tvOSSimulator. However, on MacCatalyst, it seems to be /Users/mdhwang and the tests expected paths are
Environment.GetFolderPath(Environment.SpecialFolder.Personal) evaluates to /Users/mdhwang/Documents
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) evaluates to /Users/mdhwang/Documents
Environment.GetFolderPath(Environment.SpecialFolder.UserProfile) evaluates to /Users/mdhwang

However, it seems like a previous tvOSSimulator's failure message was
Assert.Equal() Failure\n ↓ (pos 161)\nExpected: ···F1-ADDB-B49F66D98B32\nActual: ···F1-ADDB-B49F66D98B32/Documents\n ↑ (pos 161) which suggests that sometimes the Home environment variable is not empty or null? possibly flakey?

@filipnavara

GetFolderPath_Unix_PersonalIsHomeAndUserProfile is not valid for iOS, tvOS

Could you elaborate on why its not valid for iOS/tvOS?

[akoeplinger]

Hm I tried with preview7 on iOSSimulator and Environment.GetEnvironmentVariable("HOME") returned a path there. did you test with Home or HOME?

[filipnavara]

Could you elaborate on why its not valid for iOS/tvOS?

On iOS:

• Personal/MyDocuments (same enum value) returns value of NSSearchPathDirectory.NSDocumentDirectory
• UserProfile return the HOME environment variable. I remember testing it but I don't remember the value anymore, my previous comment would imply that it was null

On tvOS:

• NSSearchPathDirectory.NSDocumentDirectory is read-only so Personal/MyDocuments intentionally does NOT return it. At least that was the situation on old Mono. Apparently the code was not ported for .NET 6 and it's still tracked as an issue - Change Environment.GetFolderPath to be compatible with tvOS #34007

[mdh1418]

did you test with Home or HOME?

I used HOME and I temporarily modified the test for these OSes and it passes on MacCatalyst after this modification.

[Fact]
[PlatformSpecific(TestPlatforms.AnyUnix | TestPlatforms.Browser)]  // Tests OS-specific environment
public void GetFolderPath_Unix_PersonalIsHomeAndUserProfile()
{
    Console.WriteLine("Mitchell Hwang");
    Console.WriteLine(Environment.GetEnvironmentVariable("HOME"));
    Console.WriteLine(Environment.GetFolderPath(Environment.SpecialFolder.Personal));
    Console.WriteLine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments));
    Console.WriteLine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile));
    Assert.Equal(Environment.GetEnvironmentVariable("HOME")+"/Documents", Environment.GetFolderPath(Environment.SpecialFolder.Personal));
    Assert.Equal(Environment.GetEnvironmentVariable("HOME")+"/Documents", Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments));
    Assert.Equal(Environment.GetEnvironmentVariable("HOME"), Environment.GetFolderPath(Environment.SpecialFolder.UserProfile));
}

The most recent run locally on preview 6 was
Assert.Equal() Failure\nExpected: (null)\nActual: /Users/mdhwang/Library/Developer/CoreSimulator/Devices/71D00C72-A1BD-4EF7-87EA-B22842EC1650/data/Containers/Data/Application/E3609B50-9E46-4864-A413-A1C506C5295D/Documents

[mdh1418]

Both System.Tests.EnvironmentUserName.UserName_Valid and System.Tests.EnvironmentTests.GetFolderPath_Unix_PersonalIsHomeAndUserProfile are failing on iOS and tvOS due to the values Environment.UserName being string.Empty and Environment.GetEnvironmentVariable("HOME") being null.

On MacCatalyst, the values are not empty or null.