PowerShell/src/ps_test/test_CorePsPlatform.cs

using Xunit;
using System;
using System.IO;
using System.Diagnostics;
using System.Management.Automation;

namespace PSTests
{
    public static class PlatformTests
    {
        [Fact]
        public static void TestIsLinux()
        {
            Assert.True(Platform.IsLinux());
        }

        [Fact]
        public static void TestHasCom()
        {
            Assert.False(Platform.HasCom());
        }

        [Fact]
        public static void TestHasAmsi()
        {
            Assert.False(Platform.HasAmsi());
        }

        [Fact]
        public static void TestUsesCodeSignedAssemblies()
        {
            Assert.False(Platform.UsesCodeSignedAssemblies());
        }

        [Fact]
        public static void TestHasDriveAutoMounting()
        {
            Assert.False(Platform.HasDriveAutoMounting());
        }

        [Fact]
        public static void TestHasRegistrySupport()
        {
            Assert.False(Platform.HasRegistrySupport());
        }

        [Fact]
        public static void TestGetUserName()
        {
            var startInfo = new ProcessStartInfo
            {
                FileName = @"/usr/bin/env",
                Arguments = "whoami",
                RedirectStandardOutput = true,
                UseShellExecute = false
            };
            using (Process process = Process.Start(startInfo))
            {
                // Get output of call to whoami without trailing newline
                string username = process.StandardOutput.ReadToEnd().Trim();
                process.WaitForExit();

                // The process should return an exit code of 0 on success
                Assert.Equal(0, process.ExitCode);
                // It should be the same as what our platform code returns
                Assert.Equal(username, Platform.NonWindowsGetUserName());
            }
        }

        [Fact]
        public static void TestGetMachineName()
        {
            var startInfo = new ProcessStartInfo
            {
                FileName = @"/usr/bin/env",
                Arguments = "hostname",
                RedirectStandardOutput = true,
                UseShellExecute = false
            };
            using (Process process = Process.Start(startInfo))
            {
                 // Get output of call to hostname without trailing newline
                string hostname = process.StandardOutput.ReadToEnd().Trim();
                process.WaitForExit();

                // The process should return an exit code of 0 on success
                Assert.Equal(0, process.ExitCode);
                // It should be the same as what our platform code returns
                Assert.Equal(hostname, Platform.NonWindowsGetMachineName());
            }


        }

        [Fact]
        public static void TestIsHardLink()
        {
            // a file that should exist on every *nix distro

            string path = @"/tmp/MyTest";
            if (!File.Exists(path))
            {
                File.Create(path);
            }

            // Create a file to write to using StreamWriter. 
            // convert string to stream.  On Windows, this appears to be handled, but on *nix, we apparently need to convert to UTF8.
            byte[] byteArray    = System.Text.Encoding.UTF8.GetBytes(path);
            MemoryStream stream = new MemoryStream(byteArray);

            using (StreamWriter sw = new StreamWriter(stream))
            {
                sw.Write("Hello");
            }

            // Convert `path` string to FileSystemInfo data type. And now, it should return true
            FileSystemInfo fd = new FileInfo(path);
            Assert.True(Platform.NonWindowsIsHardLink(fd));
        }

        [Fact]
        public static void TestIsHardLinkFailsWithDirectory()
        {
             
        }

    }
}