Enable ANSI formatting via $PSStyle and support suppressing ANSI output (#13758)

src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleHostUserInterface.cs

@@ -696,6 +696,7 @@ namespace Microsoft.PowerShell
             }
 
             TextWriter writer = Console.IsOutputRedirected ? Console.Out : _parent.ConsoleTextWriter;
+            value = Utils.GetOutputString(value, isHost: true, SupportsVirtualTerminal, Console.IsOutputRedirected);
 
             if (_parent.IsRunningAsync)
             {
@@ -1179,11 +1180,17 @@ namespace Microsoft.PowerShell
             }
             else
             {
-                // NTRAID#Windows OS Bugs-1061752-2004/12/15-sburns should read a skin setting here...
-                WriteLine(
-                    DebugForegroundColor,
-                    DebugBackgroundColor,
-                    StringUtil.Format(ConsoleHostUserInterfaceStrings.DebugFormatString, message));
+                if (SupportsVirtualTerminal && ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+                {
+                    WriteLine(Utils.GetFormatStyleString(Utils.FormatStyle.Debug) + StringUtil.Format(ConsoleHostUserInterfaceStrings.DebugFormatString, message));
+                }
+                else
+                {
+                    WriteLine(
+                        DebugForegroundColor,
+                        DebugBackgroundColor,
+                        StringUtil.Format(ConsoleHostUserInterfaceStrings.DebugFormatString, message));
+                }
             }
         }
 
@@ -1234,10 +1241,17 @@ namespace Microsoft.PowerShell
             }
             else
             {
-                WriteLine(
-                    VerboseForegroundColor,
-                    VerboseBackgroundColor,
-                    StringUtil.Format(ConsoleHostUserInterfaceStrings.VerboseFormatString, message));
+                if (SupportsVirtualTerminal && ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+                {
+                    WriteLine(Utils.GetFormatStyleString(Utils.FormatStyle.Verbose) + StringUtil.Format(ConsoleHostUserInterfaceStrings.VerboseFormatString, message));
+                }
+                else
+                {
+                    WriteLine(
+                        VerboseForegroundColor,
+                        VerboseBackgroundColor,
+                        StringUtil.Format(ConsoleHostUserInterfaceStrings.VerboseFormatString, message));
+                }
             }
         }
 
@@ -1271,10 +1285,17 @@ namespace Microsoft.PowerShell
             }
             else
             {
-                WriteLine(
-                    WarningForegroundColor,
-                    WarningBackgroundColor,
-                    StringUtil.Format(ConsoleHostUserInterfaceStrings.WarningFormatString, message));
+                if (SupportsVirtualTerminal && ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+                {
+                    WriteLine(Utils.GetFormatStyleString(Utils.FormatStyle.Warning) + StringUtil.Format(ConsoleHostUserInterfaceStrings.WarningFormatString, message));
+                }
+                else
+                {
+                    WriteLine(
+                        WarningForegroundColor,
+                        WarningBackgroundColor,
+                        StringUtil.Format(ConsoleHostUserInterfaceStrings.WarningFormatString, message));
+                }
             }
         }
 
@@ -1334,9 +1355,20 @@ namespace Microsoft.PowerShell
             else
             {
                 if (writer == _parent.ConsoleTextWriter)
-                    WriteLine(ErrorForegroundColor, ErrorBackgroundColor, value);
+                {
+                    if (SupportsVirtualTerminal && ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+                    {
+                        WriteLine(value);
+                    }
+                    else
+                    {
+                        WriteLine(ErrorForegroundColor, ErrorBackgroundColor, value);
+                    }
+                }
                 else
+                {
                     Console.Error.WriteLine(value);
+                }
             }
         }
 

src/System.Management.Automation/FormatAndOutput/DefaultFormatters/PowerShellCore_format_ps1xml.cs

@@ -263,6 +263,22 @@ namespace System.Management.Automation.Runspaces
             yield return new ExtendedTypeDefinition(
                 "Microsoft.PowerShell.Commands.ByteCollection",
                 ViewsOf_Microsoft_PowerShell_Commands_ByteCollection());
+
+            yield return new ExtendedTypeDefinition(
+                "System.Management.Automation.PSStyle",
+                ViewsOf_System_Management_Automation_PSStyle());
+
+            yield return new ExtendedTypeDefinition(
+                "System.Management.Automation.PSStyle+FormattingData",
+                ViewsOf_System_Management_Automation_PSStyleFormattingData());
+
+            yield return new ExtendedTypeDefinition(
+                "System.Management.Automation.PSStyle+ForegroundColor",
+                ViewsOf_System_Management_Automation_PSStyleForegroundColor());
+
+            yield return new ExtendedTypeDefinition(
+                "System.Management.Automation.PSStyle+BackgroundColor",
+                ViewsOf_System_Management_Automation_PSStyleBackgroundColor());
         }
 
         private static IEnumerable<FormatViewDefinition> ViewsOf_System_RuntimeType()
@@ -1317,7 +1333,7 @@ namespace System.Management.Automation.Runspaces
                                             $err.CategoryInfo.GetMessage()
                                         }
                                         elseif (! $err.ErrorDetails -or ! $err.ErrorDetails.Message) {
-                                            $err.Exception.Message + $posmsg + $newline
+                                            $err.Exception.Message + $posmsg
                                         } else {
                                             $err.ErrorDetails.Message + $posmsg
                                         }
@@ -2004,5 +2020,131 @@ namespace System.Management.Automation.Runspaces
                     .GroupByProperty("Label")
                 .EndTable());
         }
+
+        private static IEnumerable<FormatViewDefinition> ViewsOf_System_Management_Automation_PSStyle()
+        {
+            yield return new FormatViewDefinition("System.Management.Automation.PSStyle",
+                ListControl.Create()
+                    .StartEntry()
+                        .AddItemScriptBlock(@"""$($_.Reset)$($_.Reset.Replace(""""`e"""",'`e'))""", label: "Reset")
+                        .AddItemScriptBlock(@"""$($_.BlinkOff)$($_.BlinkOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "BlinkOff")
+                        .AddItemScriptBlock(@"""$($_.Blink)$($_.Blink.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Blink")
+                        .AddItemScriptBlock(@"""$($_.BoldOff)$($_.BoldOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "BoldOff")
+                        .AddItemScriptBlock(@"""$($_.Bold)$($_.Bold.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Bold")
+                        .AddItemScriptBlock(@"""$($_.Hidden)$($_.Hidden.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Hidden")
+                        .AddItemScriptBlock(@"""$($_.HiddenOff)$($_.HiddenOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "HiddenOff")
+                        .AddItemScriptBlock(@"""$($_.Reverse)$($_.Reverse.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Reverse")
+                        .AddItemScriptBlock(@"""$($_.ReverseOff)$($_.ReverseOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "ReverseOff")
+                        .AddItemScriptBlock(@"""$($_.ItalicOff)$($_.ItalicOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "ItalicOff")
+                        .AddItemScriptBlock(@"""$($_.Italic)$($_.Italic.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Italic")
+                        .AddItemScriptBlock(@"""$($_.UnderlineOff)$($_.UnderlineOff.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "UnderlineOff")
+                        .AddItemScriptBlock(@"""$($_.Underline)$($_.Underline.Replace(""""`e"""",'`e'))$($_.Reset)""", label: "Underline")
+                        .AddItemProperty(@"OutputRendering")
+                        .AddItemScriptBlock(@"""$($_.Formatting.FormatAccent)$($_.Formatting.FormatAccent.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.FormatAccent")
+                        .AddItemScriptBlock(@"""$($_.Formatting.ErrorAccent)$($_.Formatting.ErrorAccent.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.ErrorAccent")
+                        .AddItemScriptBlock(@"""$($_.Formatting.Error)$($_.Formatting.Error.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.Error")
+                        .AddItemScriptBlock(@"""$($_.Formatting.Warning)$($_.Formatting.Warning.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.Warning")
+                        .AddItemScriptBlock(@"""$($_.Formatting.Verbose)$($_.Formatting.Verbose.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.Verbose")
+                        .AddItemScriptBlock(@"""$($_.Formatting.Debug)$($_.Formatting.Debug.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.Debug")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Black)$($_.Foreground.Black.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Black")
+                        .AddItemScriptBlock(@"""$($_.Foreground.White)$($_.Foreground.White.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.White")
+                        .AddItemScriptBlock(@"""$($_.Foreground.DarkGray)$($_.Foreground.DarkGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.DarkGray")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightGray)$($_.Foreground.LightGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightGray")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Red)$($_.Foreground.Red.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Red")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightRed)$($_.Foreground.LightRed.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightRed")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Magenta)$($_.Foreground.Magenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Magenta")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightMagenta)$($_.Foreground.LightMagenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightMagenta")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Blue)$($_.Foreground.Blue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Blue")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightBlue)$($_.Foreground.LightBlue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightBlue")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Cyan)$($_.Foreground.Cyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Cyan")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightCyan)$($_.Foreground.LightCyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightCyan")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Green)$($_.Foreground.Green.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Green")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightGreen)$($_.Foreground.LightGreen.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightGreen")
+                        .AddItemScriptBlock(@"""$($_.Foreground.Yellow)$($_.Foreground.Yellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.Yellow")
+                        .AddItemScriptBlock(@"""$($_.Foreground.LightYellow)$($_.Foreground.LightYellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Foreground.LightYellow")
+                        .AddItemScriptBlock(@"""$($_.Background.Black)$($_.Background.Black.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Black")
+                        .AddItemScriptBlock(@"""$($_.Background.White)$($_.Background.White.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.White")
+                        .AddItemScriptBlock(@"""$($_.Background.DarkGray)$($_.Background.DarkGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.DarkGray")
+                        .AddItemScriptBlock(@"""$($_.Background.LightGray)$($_.Background.LightGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightGray")
+                        .AddItemScriptBlock(@"""$($_.Background.Red)$($_.Background.Red.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Red")
+                        .AddItemScriptBlock(@"""$($_.Background.LightRed)$($_.Background.LightRed.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightRed")
+                        .AddItemScriptBlock(@"""$($_.Background.Magenta)$($_.Background.Magenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Magenta")
+                        .AddItemScriptBlock(@"""$($_.Background.LightMagenta)$($_.Background.LightMagenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightMagenta")
+                        .AddItemScriptBlock(@"""$($_.Background.Blue)$($_.Background.Blue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Blue")
+                        .AddItemScriptBlock(@"""$($_.Background.LightBlue)$($_.Background.LightBlue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightBlue")
+                        .AddItemScriptBlock(@"""$($_.Background.Cyan)$($_.Background.Cyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Cyan")
+                        .AddItemScriptBlock(@"""$($_.Background.LightCyan)$($_.Background.LightCyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightCyan")
+                        .AddItemScriptBlock(@"""$($_.Background.Green)$($_.Background.Green.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Green")
+                        .AddItemScriptBlock(@"""$($_.Background.LightGreen)$($_.Background.LightGreen.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightGreen")
+                        .AddItemScriptBlock(@"""$($_.Background.Yellow)$($_.Background.Yellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.Yellow")
+                        .AddItemScriptBlock(@"""$($_.Background.LightYellow)$($_.Background.LightYellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Background.LightYellow")
+                        .EndEntry()
+                .EndList());
+        }
+
+        private static IEnumerable<FormatViewDefinition> ViewsOf_System_Management_Automation_PSStyleFormattingData()
+        {
+            yield return new FormatViewDefinition("System.Management.Automation.PSStyle+FormattingData",
+                ListControl.Create()
+                    .StartEntry()
+                        .AddItemScriptBlock(@"""$($_.FormatAccent)$($_.FormatAccent.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "FormatAccent")
+                        .AddItemScriptBlock(@"""$($_.ErrorAccent)$($_.ErrorAccent.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "ErrorAccent")
+                        .AddItemScriptBlock(@"""$($_.Error)$($_.Error.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Error")
+                        .AddItemScriptBlock(@"""$($_.Warning)$($_.Warning.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Warning")
+                        .AddItemScriptBlock(@"""$($_.Verbose)$($_.Verbose.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Formatting.Verbose")
+                        .AddItemScriptBlock(@"""$($_.Debug)$($_.Debug.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Debug")
+                    .EndEntry()
+                .EndList());
+        }
+
+        private static IEnumerable<FormatViewDefinition> ViewsOf_System_Management_Automation_PSStyleForegroundColor()
+        {
+            yield return new FormatViewDefinition("System.Management.Automation.PSStyle+ForegroundColor",
+                ListControl.Create()
+                    .StartEntry()
+                        .AddItemScriptBlock(@"""$($_.Black)$($_.Black.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Black")
+                        .AddItemScriptBlock(@"""$($_.White)$($_.White.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "White")
+                        .AddItemScriptBlock(@"""$($_.DarkGray)$($_.DarkGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "DarkGray")
+                        .AddItemScriptBlock(@"""$($_.LightGray)$($_.LightGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightGray")
+                        .AddItemScriptBlock(@"""$($_.Red)$($_.Red.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Red")
+                        .AddItemScriptBlock(@"""$($_.LightRed)$($_.LightRed.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightRed")
+                        .AddItemScriptBlock(@"""$($_.Magenta)$($_.Magenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Magenta")
+                        .AddItemScriptBlock(@"""$($_.LightMagenta)$($_.LightMagenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightMagenta")
+                        .AddItemScriptBlock(@"""$($_.Blue)$($_.Blue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Blue")
+                        .AddItemScriptBlock(@"""$($_.LightBlue)$($_.LightBlue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightBlue")
+                        .AddItemScriptBlock(@"""$($_.Cyan)$($_.Cyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Cyan")
+                        .AddItemScriptBlock(@"""$($_.LightCyan)$($_.LightCyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightCyan")
+                        .AddItemScriptBlock(@"""$($_.Green)$($_.Green.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Green")
+                        .AddItemScriptBlock(@"""$($_.LightGreen)$($_.LightGreen.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightGreen")
+                        .AddItemScriptBlock(@"""$($_.Yellow)$($_.Yellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Yellow")
+                        .AddItemScriptBlock(@"""$($_.LightYellow)$($_.LightYellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightYellow")
+                    .EndEntry()
+                .EndList());
+        }
+
+        private static IEnumerable<FormatViewDefinition> ViewsOf_System_Management_Automation_PSStyleBackgroundColor()
+        {
+            yield return new FormatViewDefinition("System.Management.Automation.PSStyle+ForegroundColor",
+                ListControl.Create()
+                    .StartEntry()
+                        .AddItemScriptBlock(@"""$($_.Black)$($_.Black.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Black")
+                        .AddItemScriptBlock(@"""$($_.White)$($_.White.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "White")
+                        .AddItemScriptBlock(@"""$($_.DarkGray)$($_.DarkGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "DarkGray")
+                        .AddItemScriptBlock(@"""$($_.LightGray)$($_.LightGray.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightGray")
+                        .AddItemScriptBlock(@"""$($_.Red)$($_.Red.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Red")
+                        .AddItemScriptBlock(@"""$($_.LightRed)$($_.LightRed.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightRed")
+                        .AddItemScriptBlock(@"""$($_.Magenta)$($_.Magenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Magenta")
+                        .AddItemScriptBlock(@"""$($_.LightMagenta)$($_.LightMagenta.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightMagenta")
+                        .AddItemScriptBlock(@"""$($_.Blue)$($_.Blue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Blue")
+                        .AddItemScriptBlock(@"""$($_.LightBlue)$($_.LightBlue.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightBlue")
+                        .AddItemScriptBlock(@"""$($_.Cyan)$($_.Cyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Cyan")
+                        .AddItemScriptBlock(@"""$($_.LightCyan)$($_.LightCyan.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightCyan")
+                        .AddItemScriptBlock(@"""$($_.Green)$($_.Green.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Green")
+                        .AddItemScriptBlock(@"""$($_.LightGreen)$($_.LightGreen.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightGreen")
+                        .AddItemScriptBlock(@"""$($_.Yellow)$($_.Yellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "Yellow")
+                        .AddItemScriptBlock(@"""$($_.LightYellow)$($_.LightYellow.Replace(""""`e"""",'`e'))$($PSStyle.Reset)""", label: "LightYellow")
+                    .EndEntry()
+                .EndList());
+        }
     }
 }

src/System.Management.Automation/FormatAndOutput/common/ILineOutput.cs

@@ -4,6 +4,7 @@
 using System.Globalization;
 using System.IO;
 using System.Management.Automation;
+using System.Management.Automation.Internal;
 using System.Text;
 
 // interfaces for host interaction
@@ -411,6 +412,9 @@ namespace Microsoft.PowerShell.Commands.Internal.Format
         internal override void WriteLine(string s)
         {
             CheckStopProcessing();
+
+            s = Utils.GetOutputString(s, isHost: false);
+
             if (_suppressNewline)
             {
                 _writer.Write(s);

src/System.Management.Automation/FormatAndOutput/common/PSStyle.cs

@@ -0,0 +1,404 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+namespace System.Management.Automation
+{
+    #region OutputRendering
+    /// <summary>
+    /// Defines the options for output rendering.
+    /// </summary>
+    public enum OutputRendering
+    {
+        /// <summary>Automatic by PowerShell.</summary>
+        Automatic = 0,
+
+        /// <summary>Render as plaintext.</summary>
+        PlainText = 1,
+
+        /// <summary>Render as ANSI.</summary>
+        Ansi = 2,
+
+        /// <summary>Render ANSI only to host.</summary>
+        Host = 3,
+    }
+    #endregion OutputRendering
+
+    #region PSStyle
+    /// <summary>
+    /// Contains configuration for how PowerShell renders text.
+    /// </summary>
+    public class PSStyle
+    {
+        /// <summary>
+        /// Contains foreground colors.
+        /// </summary>
+        public class ForegroundColor
+        {
+            /// <summary>
+            /// Gets the color black.
+            /// </summary>
+            public string Black { get; } = "\x1b[30m";
+
+            /// <summary>
+            /// Gets the color blue.
+            /// </summary>
+            public string Blue { get; } = "\x1b[34m";
+
+            /// <summary>
+            /// Gets the color cyan.
+            /// </summary>
+            public string Cyan { get; } = "\x1b[36m";
+
+            /// <summary>
+            /// Gets the color dark gray.
+            /// </summary>
+            public string DarkGray { get; } = "\x1b[90m";
+
+            /// <summary>
+            /// Gets the color green.
+            /// </summary>
+            public string Green { get; } = "\x1b[32m";
+
+            /// <summary>
+            /// Gets the color light blue.
+            /// </summary>
+            public string LightBlue { get; } = "\x1b[94m";
+
+            /// <summary>
+            /// Gets the color light cyan.
+            /// </summary>
+            public string LightCyan { get; } = "\x1b[96m";
+
+            /// <summary>
+            /// Gets the color light gray.
+            /// </summary>
+            public string LightGray { get; } = "\x1b[97m";
+
+            /// <summary>
+            /// Gets the color light green.
+            /// </summary>
+            public string LightGreen { get; } = "\x1b[92m";
+
+            /// <summary>
+            /// Gets the color light magenta.
+            /// </summary>
+            public string LightMagenta { get; } = "\x1b[95m";
+
+            /// <summary>
+            /// Gets the color light red.
+            /// </summary>
+            public string LightRed { get; } = "\x1b[91m";
+
+            /// <summary>
+            /// Gets the color light yellow.
+            /// </summary>
+            public string LightYellow { get; } = "\x1b[93m";
+
+            /// <summary>
+            /// Gets the color magenta.
+            /// </summary>
+            public string Magenta { get; } = "\x1b[35m";
+
+            /// <summary>
+            /// Gets the color read.
+            /// </summary>
+            public string Red { get; } = "\x1b[31m";
+
+            /// <summary>
+            /// Gets the color white.
+            /// </summary>
+            public string White { get; } = "\x1b[37m";
+
+            /// <summary>
+            /// Gets the color yellow.
+            /// </summary>
+            public string Yellow { get; } = "\x1b[33m";
+
+            /// <summary>
+            /// Set as RGB (Red, Green, Blue).
+            /// </summary>
+            /// <param name="red">Byte value representing red.</param>
+            /// <param name="green">Byte value representing green.</param>
+            /// <param name="blue">Byte value representing blue.</param>
+            /// <returns>String representing ANSI code for RGB value.</returns>
+            public string FromRgb(byte red, byte green, byte blue)
+            {
+                return $"\x1b[38;2;{red};{green};{blue}m";
+            }
+
+            /// <summary>
+            /// The color set as RGB as a single number.
+            /// </summary>
+            /// <param name="rgb">RGB value specified as an integer.</param>
+            /// <returns>String representing ANSI code for RGB value.</returns>
+            public string FromRgb(int rgb)
+            {
+                byte red, green, blue;
+                blue = (byte)(rgb & 0xFF);
+                rgb >>= 8;
+                green = (byte)(rgb & 0xFF);
+                rgb >>= 8;
+                red = (byte)(rgb & 0xFF);
+
+                return FromRgb(red, green, blue);
+            }
+        }
+
+        /// <summary>
+        /// Contains background colors.
+        /// </summary>
+        public class BackgroundColor
+        {
+            /// <summary>
+            /// Gets the color black.
+            /// </summary>
+            public string Black { get; } = "\x1b[40m";
+
+            /// <summary>
+            /// Gets the color blue.
+            /// </summary>
+            public string Blue { get; } = "\x1b[44m";
+
+            /// <summary>
+            /// Gets the color cyan.
+            /// </summary>
+            public string Cyan { get; } = "\x1b[46m";
+
+            /// <summary>
+            /// Gets the color dark gray.
+            /// </summary>
+            public string DarkGray { get; } = "\x1b[100m";
+
+            /// <summary>
+            /// Gets the color green.
+            /// </summary>
+            public string Green { get; } = "\x1b[42m";
+
+            /// <summary>
+            /// Gets the color light blue.
+            /// </summary>
+            public string LightBlue { get; } = "\x1b[104m";
+
+            /// <summary>
+            /// Gets the color light cyan.
+            /// </summary>
+            public string LightCyan { get; } = "\x1b[106m";
+
+            /// <summary>
+            /// Gets the color light gray.
+            /// </summary>
+            public string LightGray { get; } = "\x1b[107m";
+
+            /// <summary>
+            /// Gets the color light green.
+            /// </summary>
+            public string LightGreen { get; } = "\x1b[102m";
+
+            /// <summary>
+            /// Gets the color light magenta.
+            /// </summary>
+            public string LightMagenta { get; } = "\x1b[105m";
+
+            /// <summary>
+            /// Gets the color light red.
+            /// </summary>
+            public string LightRed { get; } = "\x1b[101m";
+
+            /// <summary>
+            /// Gets the color light yellow.
+            /// </summary>
+            public string LightYellow { get; } = "\x1b[103m";
+
+            /// <summary>
+            /// Gets the color magenta.
+            /// </summary>
+            public string Magenta { get; } = "\x1b[45m";
+
+            /// <summary>
+            /// Gets the color read.
+            /// </summary>
+            public string Red { get; } = "\x1b[41m";
+
+            /// <summary>
+            /// Gets the color white.
+            /// </summary>
+            public string White { get; } = "\x1b[47m";
+
+            /// <summary>
+            /// Gets the color yellow.
+            /// </summary>
+            public string Yellow { get; } = "\x1b[43m";
+
+            /// <summary>
+            /// The color set as RGB (Red, Green, Blue).
+            /// </summary>
+            /// <param name="red">Byte value representing red.</param>
+            /// <param name="green">Byte value representing green.</param>
+            /// <param name="blue">Byte value representing blue.</param>
+            /// <returns>String representing ANSI code for RGB value.</returns>
+            public string FromRgb(byte red, byte green, byte blue)
+            {
+                return $"\x1b[48;2;{red};{green};{blue}m";
+            }
+
+            /// <summary>
+            /// The color set as RGB as a single number.
+            /// </summary>
+            /// <param name="rgb">RGB value specified as an integer.</param>
+            /// <returns>String representing ANSI code for RGB value.</returns>
+            public string FromRgb(int rgb)
+            {
+                byte red, green, blue;
+                blue = (byte)(rgb & 0xFF);
+                rgb >>= 8;
+                green = (byte)(rgb & 0xFF);
+                rgb >>= 8;
+                red = (byte)(rgb & 0xFF);
+
+                return FromRgb(red, green, blue);
+            }
+        }
+
+        /// <summary>
+        /// Contains formatting styles for steams and objects.
+        /// </summary>
+        public class FormattingData
+        {
+            /// <summary>
+            /// Gets or sets the accent style for formatting.
+            /// </summary>
+            public string FormatAccent { get; set; } = "\x1b[32;1m";
+
+            /// <summary>
+            /// Gets or sets the accent style for errors.
+            /// </summary>
+            public string ErrorAccent { get; set; } = "\x1b[36;1m";
+
+            /// <summary>
+            /// Gets or sets the style for error messages.
+            /// </summary>
+            public string Error { get; set; } = "\x1b[31;1m";
+
+            /// <summary>
+            /// Gets or sets the style for warning messages.
+            /// </summary>
+            public string Warning { get; set; } = "\x1b[33;1m";
+
+            /// <summary>
+            /// Gets or sets the style for verbose messages.
+            /// </summary>
+            public string Verbose { get; set; } = "\x1b[33;1m";
+
+            /// <summary>
+            /// Gets or sets the style for debug messages.
+            /// </summary>
+            public string Debug { get; set; } = "\x1b[33;1m";
+        }
+
+        /// <summary>
+        /// Gets or sets the rendering mode for output.
+        /// </summary>
+        public OutputRendering OutputRendering { get; set; } = OutputRendering.Automatic;
+
+        /// <summary>
+        /// Gets value to turn off all attributes.
+        /// </summary>
+        public string Reset { get; } = "\x1b[0m";
+
+        /// <summary>
+        /// Gets value to turn off blink.
+        /// </summary>
+        public string BlinkOff { get; } = "\x1b[5m";
+
+        /// <summary>
+        /// Gets value to turn on blink.
+        /// </summary>
+        public string Blink { get; } = "\x1b[25m";
+
+        /// <summary>
+        /// Gets value to turn off bold.
+        /// </summary>
+        public string BoldOff { get; } = "\x1b[22m";
+
+        /// <summary>
+        /// Gets value to turn on blink.
+        /// </summary>
+        public string Bold { get; } = "\x1b[1m";
+
+        /// <summary>
+        /// Gets value to turn on hidden.
+        /// </summary>
+        public string Hidden { get; } = "\x1b[8m";
+
+        /// <summary>
+        /// Gets value to turn off hidden.
+        /// </summary>
+        public string HiddenOff { get; } = "\x1b[28m";
+
+        /// <summary>
+        /// Gets value to turn on reverse.
+        /// </summary>
+        public string Reverse { get; } = "\x1b[7m";
+
+        /// <summary>
+        /// Gets value to turn off reverse.
+        /// </summary>
+        public string ReverseOff { get; } = "\x1b[27m";
+
+        /// <summary>
+        /// Gets value to turn off standout.
+        /// </summary>
+        public string ItalicOff { get; } = "\x1b[23m";
+
+        /// <summary>
+        /// Gets value to turn on standout.
+        /// </summary>
+        public string Italic { get; } = "\x1b[3m";
+
+        /// <summary>
+        /// Gets value to turn off underlined.
+        /// </summary>
+        public string UnderlineOff { get; } = "\x1b[24m";
+
+        /// <summary>
+        /// Gets value to turn on underlined.
+        /// </summary>
+        public string Underline { get; } = "\x1b[4m";
+
+        /// <summary>
+        /// Gets the formatting rendering settings.
+        /// </summary>
+        public FormattingData Formatting { get; }
+
+        /// <summary>
+        /// Gets foreground colors.
+        /// </summary>
+        public ForegroundColor Foreground { get; }
+
+        /// <summary>
+        /// Gets background colors.
+        /// </summary>
+        public BackgroundColor Background { get; }
+
+        private static readonly PSStyle s_psstyle = new PSStyle();
+
+        private PSStyle()
+        {
+            Formatting = new FormattingData();
+            Foreground = new ForegroundColor();
+            Background = new BackgroundColor();
+        }
+
+        /// <summary>
+        /// Gets singleton instance.
+        /// </summary>
+        public static PSStyle Instance
+        {
+            get
+            {
+                return s_psstyle;
+            }
+        }
+    }
+    #endregion PSStyle
+}

src/System.Management.Automation/FormatAndOutput/common/StringDecorated.cs

@@ -0,0 +1,175 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+#nullable enable
+
+using System.Text.RegularExpressions;
+
+namespace System.Management.Automation.Internal
+{
+    /// <summary>
+    /// Extensions to String type to calculate and render decorated content.
+    /// </summary>
+    public class StringDecorated
+    {
+        private readonly bool _isDecorated;
+        private readonly string _text;
+        private string? _plaintextcontent;
+
+        private string PlainText
+        {
+            get
+            {
+                if (_plaintextcontent == null)
+                {
+                    _plaintextcontent = ValueStringDecorated.AnsiRegex.Replace(_text, string.Empty);
+                }
+
+                return _plaintextcontent;
+            }
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="StringDecorated"/> class.
+        /// </summary>
+        /// <param name="text">The input string.</param>
+        public StringDecorated(string text)
+        {
+            _text = text;
+            _isDecorated = text.Contains(ValueStringDecorated.ESC);
+        }
+
+        /// <summary>
+        /// Gets a value indicating whether the string contains decoration.
+        /// </summary>
+        /// <returns>Boolean if the string contains decoration.</returns>
+        public bool IsDecorated => _isDecorated;
+
+        /// <summary>
+        /// Gets the length of content sans escape sequences.
+        /// </summary>
+        /// <returns>Length of content sans escape sequences.</returns>
+        public int ContentLength => PlainText.Length;
+
+        /// <summary>
+        /// Render the decorarted string using automatic output rendering.
+        /// </summary>
+        /// <returns>Rendered string based on automatic output rendering.</returns>
+        public override string ToString() => _isDecorated ? ToString(OutputRendering.Automatic) : _text;
+
+        /// <summary>
+        /// Return string representation of content depending on output rendering mode.
+        /// </summary>
+        /// <param name="outputRendering">Specify how to render the text content.</param>
+        /// <returns>Rendered string based on outputRendering.</returns>
+        public string ToString(OutputRendering outputRendering)
+        {
+            if (!_isDecorated)
+            {
+                return _text;
+            }
+
+            if (outputRendering == OutputRendering.Automatic)
+            {
+                outputRendering = OutputRendering.Ansi;
+                if (PSStyle.Instance.OutputRendering == OutputRendering.PlainText)
+                {
+                    outputRendering = OutputRendering.PlainText;
+                }
+            }
+
+            if (outputRendering == OutputRendering.PlainText)
+            {
+                return PlainText;
+            }
+            else
+            {
+                return _text;
+            }
+        }
+    }
+
+    internal struct ValueStringDecorated
+    {
+        internal const char ESC = '\x1b';
+        private readonly bool _isDecorated;
+        private readonly string _text;
+        private string? _plaintextcontent;
+
+        private string PlainText
+        {
+            get
+            {
+                if (_plaintextcontent == null)
+                {
+                    _plaintextcontent = AnsiRegex.Replace(_text, string.Empty);
+                }
+
+                return _plaintextcontent;
+            }
+        }
+
+        // replace regex with .NET 6 API once available
+        internal static readonly Regex AnsiRegex = new Regex(@"\x1B(?:[@-Z\\-_]|\[[0-?]*[ -/]*[@-~])", RegexOptions.Compiled);
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ValueStringDecorated"/> struct.
+        /// </summary>
+        /// <param name="text">The input string.</param>
+        public ValueStringDecorated(string text)
+        {
+            _text = text;
+            _isDecorated = text.Contains(ESC);
+            _plaintextcontent = null;
+        }
+
+        /// <summary>
+        /// Gets a value indicating whether the string contains decoration.
+        /// </summary>
+        /// <returns>Boolean if the string contains decoration.</returns>
+        public bool IsDecorated => _isDecorated;
+
+        /// <summary>
+        /// Gets the length of content sans escape sequences.
+        /// </summary>
+        /// <returns>Length of content sans escape sequences.</returns>
+        public int ContentLength => PlainText.Length;
+
+        /// <summary>
+        /// Render the decorarted string using automatic output rendering.
+        /// </summary>
+        /// <returns>Rendered string based on automatic output rendering.</returns>
+        public override string ToString() => _isDecorated ? ToString(OutputRendering.Automatic) : _text;
+
+        /// <summary>
+        /// Return string representation of content depending on output rendering mode.
+        /// </summary>
+        /// <param name="outputRendering">Specify how to render the text content.</param>
+        /// <returns>Rendered string based on outputRendering.</returns>
+        public string ToString(OutputRendering outputRendering)
+        {
+            if (!_isDecorated)
+            {
+                return _text;
+            }
+
+            if (outputRendering == OutputRendering.Automatic)
+            {
+                outputRendering = OutputRendering.Ansi;
+                if (PSStyle.Instance.OutputRendering == OutputRendering.PlainText)
+                {
+                    outputRendering = OutputRendering.PlainText;
+                }
+            }
+
+            if (outputRendering == OutputRendering.PlainText)
+            {
+                return PlainText;
+            }
+            else
+            {
+                return _text;
+            }
+        }
+    }
+}

src/System.Management.Automation/FormatAndOutput/out-console/ConsoleLineOutput.cs

@@ -222,6 +222,7 @@ namespace Microsoft.PowerShell.Commands.Internal.Format
         internal override void WriteLine(string s)
         {
             CheckStopProcessing();
+
             // delegate the action to the helper,
             // that will properly break the string into
             // screen lines
@@ -351,6 +352,7 @@ namespace Microsoft.PowerShell.Commands.Internal.Format
 #if TEST_MULTICELL_ON_SINGLE_CELL_LOCALE
             s = ((DisplayCellsTest)this._displayCellsPSHost).GenerateTestString(s);
 #endif
+
             switch (this.WriteStream)
             {
                 case WriteStreamType.Error:

src/System.Management.Automation/engine/ExperimentalFeature/ExperimentalFeature.cs

@@ -126,6 +126,9 @@ namespace System.Management.Automation
                 new ExperimentalFeature(
                     name: "PSSubsystemPluginModel",
                     description: "A plugin model for registering and un-registering PowerShell subsystems"),
+                new ExperimentalFeature(
+                    name: "PSAnsiRendering",
+                    description: "Enable $PSStyle variable to control ANSI rendering of strings"),
             };
             EngineExperimentalFeatures = new ReadOnlyCollection<ExperimentalFeature>(engineFeatures);
 

src/System.Management.Automation/engine/InitialSessionState.cs

@@ -4442,6 +4442,13 @@ end {
             new SessionStateVariableEntry(SpecialVariables.FirstToken, null, string.Empty),
             new SessionStateVariableEntry(SpecialVariables.StackTrace, null, string.Empty),
 
+            // Variable which controls the output rendering
+            new SessionStateVariableEntry(
+                SpecialVariables.PSStyle,
+                PSStyle.Instance,
+                RunspaceInit.PSStyleDescription,
+                ScopedItemOptions.None),
+
             // Variable which controls the encoding for piping data to a NativeCommand
             new SessionStateVariableEntry(
                 SpecialVariables.OutputEncoding,

src/System.Management.Automation/engine/SpecialVariables.cs

@@ -32,6 +32,10 @@ namespace System.Management.Automation
 
         internal static readonly VariablePath OFSVarPath = new VariablePath(OFS);
 
+        internal const string PSStyle = "PSStyle";
+
+        internal static readonly VariablePath PSStyleVarPath = new VariablePath(PSStyle);
+
         internal const string OutputEncoding = "OutputEncoding";
 
         internal static readonly VariablePath OutputEncodingVarPath = new VariablePath(OutputEncoding);

src/System.Management.Automation/engine/Utils.cs

@@ -1787,6 +1787,107 @@ namespace System.Management.Automation
             return true;
         }
 
+        internal static bool ShouldOutputPlainText(bool isHost, bool? supportsVirtualTerminal)
+        {
+            var outputRendering = OutputRendering.Ansi;
+
+            if (ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+            {
+                if (supportsVirtualTerminal != false)
+                {
+                    switch (PSStyle.Instance.OutputRendering)
+                    {
+                        case OutputRendering.Automatic:
+                            outputRendering = OutputRendering.Ansi;
+                            break;
+                        case OutputRendering.Host:
+                            outputRendering = isHost ? OutputRendering.Ansi : OutputRendering.PlainText;
+                            break;
+                        default:
+                            outputRendering = PSStyle.Instance.OutputRendering;
+                            break;
+                    }
+                }
+            }
+
+            return outputRendering == OutputRendering.PlainText;
+        }
+
+        internal static string GetOutputString(string s, bool isHost, bool? supportsVirtualTerminal = null, bool isOutputRedirected = false)
+        {
+            if (ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+            {
+                var sd = new ValueStringDecorated(s);
+
+                if (sd.IsDecorated)
+                {
+                    var outputRendering = OutputRendering.Ansi;
+                    if (InternalTestHooks.BypassOutputRedirectionCheck)
+                    {
+                        isOutputRedirected = false;
+                    }
+
+                    if (isOutputRedirected || ShouldOutputPlainText(isHost, supportsVirtualTerminal))
+                    {
+                        outputRendering = OutputRendering.PlainText;
+                    }
+
+                    s = sd.ToString(outputRendering);
+                }
+            }
+
+            return s;
+        }
+
+        internal enum FormatStyle
+        {
+            Reset,
+            FormatAccent,
+            ErrorAccent,
+            Error,
+            Warning,
+            Verbose,
+            Debug,
+        }
+
+        internal static string GetFormatStyleString(FormatStyle formatStyle)
+        {
+            // redirected console gets plaintext output to preserve existing behavior
+            if (!InternalTestHooks.BypassOutputRedirectionCheck &&
+                ((PSStyle.Instance.OutputRendering == OutputRendering.PlainText) ||
+                (formatStyle == FormatStyle.Error && Console.IsErrorRedirected) ||
+                (formatStyle != FormatStyle.Error && Console.IsOutputRedirected)))
+            {
+                return string.Empty;
+            }
+
+            if (ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+            {
+                PSStyle psstyle = PSStyle.Instance;                
+                switch (formatStyle)
+                {
+                    case FormatStyle.Reset:
+                        return psstyle.Reset;
+                    case FormatStyle.FormatAccent:
+                        return psstyle.Formatting.FormatAccent;
+                    case FormatStyle.ErrorAccent:
+                        return psstyle.Formatting.ErrorAccent;
+                    case FormatStyle.Error:
+                        return psstyle.Formatting.Error;
+                    case FormatStyle.Warning:
+                        return psstyle.Formatting.Warning;
+                    case FormatStyle.Verbose:
+                        return psstyle.Formatting.Verbose;
+                    case FormatStyle.Debug:
+                        return psstyle.Formatting.Debug;
+                    default:
+                        return string.Empty;
+                }
+            }
+
+            return string.Empty;
+        }
+
         #endregion
     }
 
@@ -1970,6 +2071,7 @@ namespace System.Management.Automation.Internal
         internal static bool BypassAppLockerPolicyCaching;
         internal static bool BypassOnlineHelpRetrieval;
         internal static bool ForcePromptForChoiceDefaultOption;
+        internal static bool BypassOutputRedirectionCheck;
 
         // Stop/Restart/Rename Computer tests
         internal static bool TestStopComputer;

src/System.Management.Automation/engine/hostifaces/MshHostUserInterface.cs

@@ -619,6 +619,16 @@ namespace System.Management.Automation.Host
                     }
 
                     resultText = resultText.TrimEnd();
+
+                    if (ExperimentalFeature.IsEnabled("PSAnsiRendering"))
+                    {
+                        var text = new ValueStringDecorated(resultText);
+                        if (text.IsDecorated)
+                        {
+                            resultText = text.ToString(OutputRendering.PlainText);
+                        }
+                    }
+
                     foreach (TranscriptionOption transcript in TranscriptionData.Transcripts.Prepend<TranscriptionOption>(TranscriptionData.SystemTranscript))
                     {
                         if (transcript != null)

src/System.Management.Automation/resources/RunspaceInit.resx

@@ -153,6 +153,9 @@
   <data name="OutputEncodingDescription" xml:space="preserve">
     <value>The text encoding used when piping text to a native executable file</value>
   </data>
+  <data name="PSStyleDescription" xml:space="preserve">
+    <value>Configuration controlling how text is rendered.</value>
+  </data>
   <data name="PSEmailServerDescription" xml:space="preserve">
     <value>Variable to contain the name of the email server. This can be used instead of the HostName parameter in the Send-MailMessage cmdlet.</value>
   </data>

test/powershell/engine/Formatting/OutputRendering.Tests.ps1

@@ -0,0 +1,85 @@
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+
+Describe 'OutputRendering tests' {
+    BeforeAll {
+        $PSDefaultParameterValues.Add('It:Skip', (-not $EnabledExperimentalFeatures.Contains('PSAnsiRendering')))
+        $th = New-TestHost
+        $rs = [runspacefactory]::Createrunspace($th)
+        $rs.open()
+        $ps = [powershell]::Create()
+        $ps.Runspace = $rs
+    }
+
+    AfterAll {
+        $PSDefaultParameterValues.Remove('It:Skip')
+    }
+
+    BeforeEach {
+        if ($null -ne $PSStyle) {
+            $oldOutputRendering = $PSStyle.OutputRendering
+        }
+    }
+
+    AfterEach {
+        if ($null -ne $PSStyle) {
+            $PSStyle.OutputRendering = $oldOutputRendering
+        }
+
+        $ps.Commands.Clear()
+    }
+
+    It 'OutputRendering works for "<outputRendering>" to the host' -TestCases @(
+        @{ outputRendering = 'automatic'; ansi = $true }
+        @{ outputRendering = 'host'     ; ansi = $true }
+        @{ outputRendering = 'ansi'     ; ansi = $true }
+        @{ outputRendering = 'plaintext'; ansi = $false }
+    ) {
+        param($outputRendering, $ansi)
+
+        $out = pwsh -noprofile -command "[System.Management.Automation.Internal.InternalTestHooks]::SetTestHook('BypassOutputRedirectionCheck', `$true); `$PSStyle.OutputRendering = '$outputRendering'; write-host '$($PSStyle.Foreground.Green)hello'"
+
+        if ($ansi) {
+            $out | Should -BeLike "*`e*" -Because ($out | Format-Hex | Out-String)
+        }
+        else {
+            $out | Should -Not -BeLike "*`e*" -Because ($out | Format-Hex | Out-String)
+        }
+    }
+
+    It 'OutputRendering works for "<outputRendering>" to the pipeline' -TestCases @(
+        @{ outputRendering = 'automatic'; ansi = $true }
+        @{ outputRendering = 'host'     ; ansi = $false }
+        @{ outputRendering = 'ansi'     ; ansi = $true }
+        @{ outputRendering = 'plaintext'; ansi = $false }
+    ) {
+        param($outputRendering, $ansi)
+
+        $PSStyle.OutputRendering = $outputRendering
+        $out = "$($PSStyle.Foreground.Green)hello" | Out-String
+
+        if ($ansi) {
+            $out | Should -BeLike "*`e*" -Because ($out | Format-Hex | Out-String)
+        }
+        else {
+            $out | Should -Not -BeLike "*`e*" -Because ($out | Format-Hex | Out-String)
+        }
+    }
+
+    # Error isn't covered here because it has custom formatting
+    It 'OutputRendering is correct for <stream>' -TestCases @(
+        @{ stream = 'Verbose' }
+        @{ stream = 'Debug' }
+        @{ stream = 'Warning' }
+    ) {
+        param($stream)
+
+        if ($stream -ne 'Warning')
+        {
+            $switch = "-$stream"
+        }
+
+        $out = pwsh -noprofile -command "[System.Management.Automation.Internal.InternalTestHooks]::SetTestHook('BypassOutputRedirectionCheck', `$true); write-$stream $switch 'hello'"
+        $out | Should -BeExactly "$($PSStyle.Formatting.$stream)$($stream.ToUpper()): hello"
+    }
+}

test/powershell/engine/Formatting/PSStyle.Tests.ps1

@@ -0,0 +1,114 @@
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+
+Describe 'Tests for $PSStyle automatic variable' {
+    BeforeAll {
+        $PSDefaultParameterValues.Add('It:Skip', (-not $EnabledExperimentalFeatures.Contains('PSAnsiRendering')))
+        $styleDefaults = @{
+            Reset = "`e[0m"
+            BlinkOff = "`e[5m"
+            Blink = "`e[25m"
+            BoldOff = "`e[22m"
+            Bold = "`e[1m"
+            HiddenOff = "`e[28m"
+            Hidden = "`e[8m"
+            ReverseOff = "`e[27m"
+            Reverse = "`e[7m"
+            ItalicOff = "`e[23m"
+            Italic = "`e[3m"
+            UnderlineOff = "`e[24m"
+            Underline = "`e[4m"
+        }
+
+        $formattingDefaults = @{
+            FormatAccent = "`e[32;1m"
+            ErrorAccent = "`e[36;1m"
+            Error = "`e[31;1m"
+            Debug = "`e[33;1m"
+            Verbose = "`e[33;1m"
+            Warning = "`e[33;1m"
+        }
+
+        $foregroundDefaults = @{
+            Black = "`e[30m"
+            White = "`e[37m"
+            DarkGray = "`e[90m"
+            LightGray = "`e[97m"
+            Red = "`e[31m"
+            LightRed = "`e[91m"
+            Magenta = "`e[35m"
+            LightMagenta = "`e[95m"
+            Blue = "`e[34m"
+            LightBlue = "`e[94m"
+            Cyan = "`e[36m"
+            LightCyan = "`e[96m"
+            Green = "`e[32m"
+            LightGreen = "`e[92m"
+            Yellow = "`e[33m"
+            LightYellow = "`e[93m"
+        }
+
+        $backgroundDefaults = @{
+            Black = "`e[40m"
+            White = "`e[47m"
+            DarkGray = "`e[100m"
+            LightGray = "`e[107m"
+            Red = "`e[41m"
+            LightRed = "`e[101m"
+            Magenta = "`e[45m"
+            LightMagenta = "`e[105m"
+            Blue = "`e[44m"
+            LightBlue = "`e[104m"
+            Cyan = "`e[46m"
+            LightCyan = "`e[106m"
+            Green = "`e[42m"
+            LightGreen = "`e[102m"
+            Yellow = "`e[43m"
+            LightYellow = "`e[103m"
+        }
+
+        function Get-TestCases($hashtable) {
+            $testcases = [System.Collections.Generic.List[hashtable]]::new()
+            foreach ($key in $hashtable.Keys) {
+                $testcases.Add(
+                    @{ Key = $key; Value = $hashtable[$key] }
+                )
+            }
+
+            return $testcases
+        }
+    }
+
+    AfterAll {
+        $PSDefaultParameterValues.Remove('It:Skip')
+    }
+
+    It '$PSStyle has correct default for OutputRendering' {
+        $PSStyle | Should -Not -BeNullOrEmpty
+        $PSStyle.OutputRendering | Should -BeExactly 'Automatic'
+    }
+
+    It '$PSStyle has correct defaults for style <key>' -TestCases (Get-TestCases $styleDefaults) {
+        param($key, $value)
+
+        $PSStyle.$key | Should -BeExactly $value
+    }
+
+    It '$PSStyle.Formatting has correct default for <key>' -TestCases (Get-TestCases $formattingDefaults) {
+        param($key, $value)
+
+        $PSStyle.Formatting.$key | Should -BeExactly $value
+    }
+
+    It '$PSStyle.Foreground has correct default for <key>' -TestCases (Get-TestCases $foregroundDefaults) {
+        param($key, $value)
+
+        $PSStyle.Foreground.$key | Should -BeExactly $value
+    }
+
+    It '$PSStyle.Background has correct default for <key>' -TestCases (Get-TestCases $backgroundDefaults) {
+        param($key, $value)
+
+        $PSStyle.Background.$key | Should -BeExactly $value
+    }
+}