PowerShell Progress Bar Host Shim (PowerShell/PowerShell#12541)

host.cs

using System;
using System.Globalization;
using System.Management.Automation.Host;

namespace ProgressBarShim
{
    public class Host : PSHost
    {
        private readonly PSHost PSHost;
        private readonly HostUI HostUI;

        public Host(PSHost host){
            PSHost=host;
            HostUI = new HostUI(PSHost.UI);
        }

        public override CultureInfo CurrentCulture => PSHost.CurrentCulture;

        public override CultureInfo CurrentUICulture => PSHost.CurrentUICulture;

        public override Guid InstanceId => PSHost.InstanceId;

        public override string Name => PSHost.Name;

        public override PSHostUserInterface UI => HostUI;

        public override Version Version => PSHost.Version;

        public override void EnterNestedPrompt()
        {
            PSHost.EnterNestedPrompt();
        }

        public override void ExitNestedPrompt()
        {
            PSHost.ExitNestedPrompt();
        }

        public override void NotifyBeginApplication()
        {
            PSHost.NotifyBeginApplication();
        }

        public override void NotifyEndApplication()
        {
            PSHost.NotifyEndApplication();
        }

        public override void SetShouldExit(int exitCode)
        {
            PSHost.SetShouldExit(exitCode);
        }
    }
}

shim.Example.ps1

Add-Type -Path .\host.cs,.\ui.cs
$hostShim = [ProgressBarShim.Host]::new($Host)
$rs = [runspacefactory]::CreateRunspace($hostShim)
$rs.Open()
$sb = {
    1..10 | % {
        Write-Progress 'Activity' 'Status' 1 -PercentComplete ($_*10) -SourceId 99
        sleep -Milliseconds 100
    }
}
$ps = [powershell]::Create($rs).AddScript($sb)
$ps.Invoke()

ui.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Management.Automation;
using System.Management.Automation.Host;
using System.Security;

namespace ProgressBarShim
{
    internal class HostUI : PSHostUserInterface
    {
        private readonly PSHostUserInterface PSHostUI;

        public HostUI(PSHostUserInterface psHostUI)=>PSHostUI=psHostUI;

        public override PSHostRawUserInterface RawUI => PSHostUI.RawUI;

        public override Dictionary<string, PSObject> Prompt(string caption, string message, Collection<FieldDescription> descriptions)
        {
            return PSHostUI.Prompt(caption, message, descriptions);
        }

        public override int PromptForChoice(string caption, string message, Collection<ChoiceDescription> choices, int defaultChoice)
        {
            return PSHostUI.PromptForChoice(caption, message, choices, defaultChoice);
        }

        public override PSCredential PromptForCredential(string caption, string message, string userName, string targetName, PSCredentialTypes allowedCredentialTypes, PSCredentialUIOptions options)
        {
            return PSHostUI.PromptForCredential(caption, message, userName, targetName, allowedCredentialTypes, options);
        }

        public override PSCredential PromptForCredential(string caption, string message, string userName, string targetName)
        {
            return PSHostUI.PromptForCredential(caption, message, userName, targetName);
        }

        public override string ReadLine()
        {
            return PSHostUI.ReadLine();
        }

        public override SecureString ReadLineAsSecureString()
        {
            return PSHostUI.ReadLineAsSecureString();
        }

        public override void Write(ConsoleColor foregroundColor, ConsoleColor backgroundColor, string value)
        {
            PSHostUI.Write(foregroundColor, backgroundColor, value);
        }

        public override void Write(string value)
        {
            PSHostUI.Write(value);
        }

        public override void WriteDebugLine(string message)
        {
            PSHostUI.WriteDebugLine(message);
        }

        public override void WriteErrorLine(string value)
        {
            PSHostUI.WriteErrorLine(value);
        }

        public override void WriteLine(string value)
        {
            PSHostUI.WriteLine(value);
        }

        public override void WriteProgress(long sourceId, ProgressRecord record)
        {
            ProgressRecord r = new ProgressRecord(
                record.ActivityId,
                $"{sourceId} {record.Activity}",
                record.StatusDescription
            ) {
                CurrentOperation = record.CurrentOperation,
                ParentActivityId = record.ParentActivityId,
                PercentComplete  = record.PercentComplete,
                RecordType       = record.RecordType,
                SecondsRemaining = record.SecondsRemaining
            };
            PSHostUI.WriteProgress(sourceId, r);
        }

        public override void WriteVerboseLine(string message)
        {
            PSHostUI.WriteVerboseLine(message);
        }

        public override void WriteWarningLine(string message)
        {
            PSHostUI.WriteWarningLine(message);
        }
    }
}