Support mapping foreground/background ConsoleColor values to VT escape sequences (#17938)

src/Microsoft.PowerShell.Commands.Utility/commands/utility/MatchString.cs

@@ -315,8 +315,8 @@ namespace Microsoft.PowerShell.Commands
         /// <returns>The matched line with matched text inverted.</returns>
         private string EmphasizeLine()
         {
-            string invertColorsVT100 = VTUtility.GetEscapeSequence(VTUtility.VT.Inverse);
-            string resetVT100 = VTUtility.GetEscapeSequence(VTUtility.VT.Reset);
+            string invertColorsVT100 = PSStyle.Instance.Reverse;
+            string resetVT100 = PSStyle.Instance.Reset;
 
             char[] chars = new char[(_matchIndexes.Count * (invertColorsVT100.Length + resetVT100.Length)) + Line.Length];
             int lineIndex = 0;

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

@@ -816,9 +816,7 @@ namespace System.Management.Automation.Runspaces
                                     $errorColor = $psstyle.Formatting.Error
                                 }
 
-                                $resetColor = [System.Management.Automation.VTUtility]::GetEscapeSequence(
-                                    [System.Management.Automation.VTUtility+VT]::Reset
-                                )
+                                $resetColor = $PSStyle.Reset
                             }
 
                             function Get-VT100Color([ConsoleColor] $color) {
@@ -826,7 +824,7 @@ namespace System.Management.Automation.Runspaces
                                     return ''
                                 }
 
-                                return [System.Management.Automation.VTUtility]::GetEscapeSequence($color)
+                                return [System.Management.Automation.PSStyle]::MapForegroundColorToEscapeSequence($color)
                             }
 
                             function Show-ErrorRecord($obj, [int]$indent = 0, [int]$depth = 1) {
@@ -1070,9 +1068,7 @@ namespace System.Management.Automation.Runspaces
 
                                         $resetColor = ''
                                         if ($Host.UI.SupportsVirtualTerminal -and ([string]::IsNullOrEmpty($env:__SuppressAnsiEscapeSequences))) {
-                                            $resetColor = [System.Management.Automation.VTUtility]::GetEscapeSequence(
-                                                [System.Management.Automation.VTUtility+VT]::Reset
-                                            )
+                                            $resetColor = $PSStyle.Reset
                                         }
 
                                         function Get-VT100Color([ConsoleColor] $color) {
@@ -1080,21 +1076,7 @@ namespace System.Management.Automation.Runspaces
                                                 return ''
                                             }
 
-                                            return [System.Management.Automation.VTUtility]::GetEscapeSequence($color)
-                                        }
-
-                                        # return length of string sans VT100 codes
-                                        function Get-RawStringLength($string) {
-                                            $vtCodes = ""`e[0m"", ""`e[2;30m"", ""`e[2;31m"", ""`e[2;32m"", ""`e[2;33m"", ""`e[2;34m"",
-                                                ""`e[2;35m"", ""`e[2;36m"", ""`e[2;37m"", ""`e[1;30m"", ""`e[1;31m"", ""`e[1;32m"",
-                                                ""`e[1;33m"", ""`e[1;34m"", ""`e[1;35m"", ""`e[1;36m"", ""`e[1;37m""
-
-                                            $newString = $string
-                                            foreach ($vtCode in $vtCodes) {
-                                                $newString = $newString.Replace($vtCode, '')
-                                            }
-
-                                            return $newString.Length
+                                            return [System.Management.Automation.PSStyle]::MapForegroundColorToEscapeSequence($color)
                                         }
 
                                         # returns a string cut to last whitespace
@@ -1217,7 +1199,7 @@ namespace System.Management.Automation.Runspaces
 
                                         # if rendering line information, break up the message if it's wider than the console
                                         if ($myinv -and $myinv.ScriptName -or $err.CategoryInfo.Category -eq 'ParserError') {
-                                            $prefixLength = Get-RawStringLength -string $prefix
+                                            $prefixLength = [System.Management.Automation.Internal.StringDecorated]::new($prefix).ContentLength
                                             $prefixVtLength = $prefix.Length - $prefixLength
 
                                             # replace newlines in message so it lines up correct

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

@@ -155,6 +155,16 @@ namespace System.Management.Automation
 
                 return FromRgb(red, green, blue);
             }
+
+            /// <summary>
+            /// Return the VT escape sequence for a foreground color.
+            /// </summary>
+            /// <param name="color">The foreground color to be mapped from.</param>
+            /// <returns>The VT escape sequence representing the foreground color.</returns>
+            public string FromConsoleColor(ConsoleColor color)
+            {
+                return MapForegroundColorToEscapeSequence(color);
+            }
         }
 
         /// <summary>
@@ -270,6 +280,16 @@ namespace System.Management.Automation
 
                 return FromRgb(red, green, blue);
             }
+
+            /// <summary>
+            /// Return the VT escape sequence for a background color.
+            /// </summary>
+            /// <param name="color">The background color to be mapped from.</param>
+            /// <returns>The VT escape sequence representing the background color.</returns>
+            public string FromConsoleColor(ConsoleColor color)
+            {
+                return MapBackgroundColorToEscapeSequence(color);
+            }
         }
 
         /// <summary>
@@ -722,6 +742,116 @@ namespace System.Management.Automation
                 return s_psstyle;
             }
         }
+
+        /// <summary>
+        /// The map of background console colors to escape sequences.
+        /// </summary>
+        private static readonly string[] BackgroundColorMap =
+            {
+                "\x1b[40m", // Black
+                "\x1b[44m", // DarkBlue
+                "\x1b[42m", // DarkGreen
+                "\x1b[46m", // DarkCyan
+                "\x1b[41m", // DarkRed
+                "\x1b[45m", // DarkMagenta
+                "\x1b[43m", // DarkYellow
+                "\x1b[47m", // Gray
+                "\x1b[100m", // DarkGray
+                "\x1b[104m", // Blue
+                "\x1b[102m", // Green
+                "\x1b[106m", // Cyan
+                "\x1b[101m", // Red
+                "\x1b[105m", // Magenta
+                "\x1b[103m", // Yellow
+                "\x1b[107m", // White
+            };
+
+        /// <summary>
+        /// The map of foreground console colors to escape sequences.
+        /// </summary>
+        private static readonly string[] ForegroundColorMap =
+            {
+                "\x1b[30m", // Black
+                "\x1b[34m", // DarkBlue
+                "\x1b[32m", // DarkGreen
+                "\x1b[36m", // DarkCyan
+                "\x1b[31m", // DarkRed
+                "\x1b[35m", // DarkMagenta
+                "\x1b[33m", // DarkYellow
+                "\x1b[37m", // Gray
+                "\x1b[90m", // DarkGray
+                "\x1b[94m", // Blue
+                "\x1b[92m", // Green
+                "\x1b[96m", // Cyan
+                "\x1b[91m", // Red
+                "\x1b[95m", // Magenta
+                "\x1b[93m", // Yellow
+                "\x1b[97m", // White
+            };
+
+        /// <summary>
+        /// Return the VT escape sequence for a ConsoleColor.
+        /// </summary>
+        /// <param name="color">The <see cref="ConsoleColor"/> to be mapped from.</param>
+        /// <param name="isBackground">Whether or not it's a background color.</param>
+        /// <returns>The VT escape sequence representing the color.</returns>
+        internal static string MapColorToEscapeSequence(ConsoleColor color, bool isBackground)
+        {
+            int index = (int)color;
+            if (index < 0 || index >= ForegroundColorMap.Length)
+            {
+                throw new ArgumentOutOfRangeException(paramName: nameof(color));
+            }
+
+            return (isBackground ? BackgroundColorMap : ForegroundColorMap)[index];
+        }
+
+        /// <summary>
+        /// Return the VT escape sequence for a foreground color.
+        /// </summary>
+        /// <param name="foregroundColor">The foreground color to be mapped from.</param>
+        /// <returns>The VT escape sequence representing the foreground color.</returns>
+        public static string MapForegroundColorToEscapeSequence(ConsoleColor foregroundColor)
+            => MapColorToEscapeSequence(foregroundColor, isBackground: false);
+
+        /// <summary>
+        /// Return the VT escape sequence for a background color.
+        /// </summary>
+        /// <param name="backgroundColor">The background color to be mapped from.</param>
+        /// <returns>The VT escape sequence representing the background color.</returns>
+        public static string MapBackgroundColorToEscapeSequence(ConsoleColor backgroundColor)
+            => MapColorToEscapeSequence(backgroundColor, isBackground: true);
+
+        /// <summary>
+        /// Return the VT escape sequence for a pair of foreground and background colors.
+        /// </summary>
+        /// <param name="foregroundColor">The foreground color of the color pair.</param>
+        /// <param name="backgroundColor">The background color of the color pair.</param>
+        /// <returns>The VT escape sequence representing the foreground and background color pair.</returns>
+        public static string MapColorPairToEscapeSequence(ConsoleColor foregroundColor, ConsoleColor backgroundColor)
+        {
+            int foreIndex = (int)foregroundColor;
+            int backIndex = (int)backgroundColor;
+
+            if (foreIndex < 0 || foreIndex >= ForegroundColorMap.Length)
+            {
+                throw new ArgumentOutOfRangeException(paramName: nameof(foregroundColor));
+            }
+
+            if (backIndex < 0 || backIndex >= ForegroundColorMap.Length)
+            {
+                throw new ArgumentOutOfRangeException(paramName: nameof(backgroundColor));
+            }
+
+            string foreground = ForegroundColorMap[foreIndex];
+            string background = BackgroundColorMap[backIndex];
+
+            return string.Concat(
+                foreground.AsSpan(start: 0, length: foreground.Length - 1),
+                ";".AsSpan(),
+                background.AsSpan(start: 2));
+        }
     }
+
     #endregion PSStyle
 }

src/System.Management.Automation/utils/VTUtils.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+using System;
 using System.Collections.Generic;
 
 namespace System.Management.Automation
@@ -8,6 +9,7 @@ namespace System.Management.Automation
     /// <summary>
     /// Class to help with VT escape sequences.
     /// </summary>
+    [Obsolete("This class is deprecated. Use 'System.Management.Automation.PSStyle' instead.", error: true)]
     public sealed class VTUtility
     {
         /// <summary>