Fix test:

- Add output encoding option to tests to capture stdout
- Update test to specify encoding

Author: chsienki

src/Cli/Microsoft.DotNet.Cli.Utils/BuiltInCommand.cs

@@ -181,4 +181,9 @@ public ICommand SetCommandArgs(string commandArgs)
     {
         throw new NotImplementedException();
     }
+
+    public ICommand StandardOutputEncoding(Encoding commandArgs)
+    {
+        throw new NotImplementedException();
+    }
 }

src/Cli/Microsoft.DotNet.Cli.Utils/Command.cs

@@ -101,6 +101,12 @@ public ICommand EnvironmentVariable(string name, string? value)
         return this;
     }
 
+    public ICommand StandardOutputEncoding(Encoding encoding)
+    {
+        _process.StartInfo.StandardOutputEncoding = encoding;
+        return this;
+    }
+
     public ICommand CaptureStdOut()
     {
         ThrowIfRunning();

src/Cli/Microsoft.DotNet.Cli.Utils/ICommand.cs

@@ -25,6 +25,8 @@ public interface ICommand
 
     ICommand SetCommandArgs(string commandArgs);
 
+    ICommand StandardOutputEncoding(Encoding encoding);
+
     string CommandName { get; }
 
     string CommandArgs { get; }

test/Microsoft.NET.TestFramework/Commands/TestCommand.cs

@@ -26,6 +26,8 @@ public abstract class TestCommand
         public Action<string>? CommandOutputHandler { get; set; }
         public Action<Process>? ProcessStartedHandler { get; set; }
 
+        public Encoding? StandardOutputEncoding { get; set; }
+
         protected TestCommand(ITestOutputHelper log)
         {
             Log = log;
@@ -57,6 +59,12 @@ public TestCommand WithStandardInput(string stdin)
             return this;
         }
 
+        public TestCommand WithStandardOutputEncoding(Encoding encoding)
+        {
+            StandardOutputEncoding = encoding;
+            return this;
+        }
+
         /// <summary>
         /// Instructs not to escape the arguments when launching command.
         /// This may be used to pass ready arguments line as single string argument.
@@ -153,6 +161,11 @@ public virtual CommandResult Execute(IEnumerable<string> args)
             {
                 Log.WriteLine($"❌{line}");
             });
+
+            if (StandardOutputEncoding is not null)
+            {
+                command.StandardOutputEncoding(StandardOutputEncoding);
+            }
 
             string fileToShow = Path.GetFileNameWithoutExtension(spec.FileName!).Equals("dotnet", StringComparison.OrdinalIgnoreCase) ?
                 "dotnet" :

test/dotnet.Tests/CommandTests/Run/RunFileTests.cs

@@ -1565,6 +1565,7 @@ public void EntryPointFilePath_WithUnicodeCharacters()
 
         new DotnetCommand(Log, "run", unicodeFileName)
             .WithWorkingDirectory(testInstance.Path)
+            .WithStandardOutputEncoding(Encoding.UTF8)
             .Execute()
             .Should().Pass()
             .And.HaveStdOut($"EntryPointFilePath: {filePath}");