Runtime: Microsoft.VisualBasic tests fail on Android

[mdh1418]

Several tests from Microsoft.VisualBasic fail on Android

Microsoft.VisualBasic.Core.Tests:

List of test failures
XML of test failures

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[ehasis]

I would like to do this, just need to know how to execute the tests.

[mdh1418]

Hi Edison, this is the workflow for running the library tests on Android. https://github.com/dotnet/runtime/blob/master/docs/workflow/testing/libraries/testing-android.md

[ehasis]

Hello @mdh1418 I have managed to build the sources as those instructions, except that is failing to build the test. Here is the error message:
/home/henrique/source/repos/runtime/eng/testing/tests.mobile.targets(69,3): error MSB4019: The imported project "/home/henrique/source/repos/runtime/artifacts/bin/MonoAOTCompiler/Debug/net5.0/MonoAOTCompiler.props" was not found. Confirm that the expression in the Import declaration "/home/henrique/source/repos/runtime/artifacts/bin/MonoAOTCompiler/Debug/net5.0/MonoAOTCompiler.props" is correct, and that the file exists on disk. [/home/henrique/source/repos/runtime/src/libraries/Microsoft.VisualBasic.Core/tests/Microsoft.VisualBasic.Core.Tests.csproj]
Not sure to get this MonoAOTCompiler.

[ehasis]

Nevermind, I cleared local repo and did a full build and worked.

[ehasis]

I have a doubt in how to deal with this. Most of the tests are failing because of empty test data for [Theory] tests. Except in couple cases, all others seems "impossible" to test the conditions. For example, take this test:
```c#
[Theory]
[MemberData(nameof(Val_Char_ArgumentException_TestData))]
public void Val_ArgumentException_Char(char value)
{
Assert.Throws(() => Conversion.Val(value));
}

public static IEnumerable {
yield break; // Add more...
}

And now Val function:
```vb.net
Public Function Val(ByVal Expression As Char) As Integer
    'Val only handles Ascii decimal chars '0' to '9'
    Dim CharValue As Integer
    CharValue = AscW(Expression) 'CType(Expression, IConvertible).ToInt32(Nothing)
    If CharValue >= AscW("1"c) AndAlso CharValue <= AscW("9"c) Then
        Return CharValue - AscW("0")
    End If
    Return 0
End Function

There is no way to test ArgumentException (at least I could not find a way), so, should I delete this kind test or just disable for Android (Mono)?

[cston]

@ehasis, thanks for investigating.

I agree, it looks like several of the empty test data and associated tests can be removed because the conditions being tested cannot be hit: Val_Char_ArgumentException_TestData, Val_Char_OverflowException_TestData.

Are there values for the other empty test data that would satisfy the conditions being tested? For instance:

public static IEnumerable<object[]> Val_Object_OverflowException_TestData()
{
    yield return "123456e789";
}

[ehasis]

Are there values for the other empty test data that would satisfy the conditions being tested?

Yes, there are and I'm working on it.

[ehasis]

Ok, I've managed to almost resolve this issue, except the test bellow. Is failing on Assert.False(string.IsNullOrEmpty(actual)). Any suggestion?
c# [Fact] public void Command() { var expected = Environment.CommandLine; var actual = Interaction.Command(); Assert.False(string.IsNullOrEmpty(actual)); Assert.EndsWith(actual, expected); }

[cston]

Is failing on Assert.False(string.IsNullOrEmpty(actual)).

Perhaps Environment.CommandLine is returning null or "". We could log a specific bug and follow up on this test failure separately if that is blocking.