Make the prediction color configurable via 'Set-PSReadLineOptions'

Author: daxian-dbw

PSReadLine/Cmdlets.cs

@@ -78,6 +78,10 @@ public class PSConsoleReadLineOptions
         public const ConsoleColor DefaultEmphasisColor  = ConsoleColor.Cyan;
         public const ConsoleColor DefaultErrorColor     = ConsoleColor.Red;
 
+        // Use dark black by default for the suggestion text.
+        // Find the most suitable color using https://stackoverflow.com/a/33206814
+        public const string DefaultPredictionColor = "\x1b[38;5;238m";
+
         public static EditMode DefaultEditMode = RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
             ? EditMode.Windows
             : EditMode.Emacs;
@@ -407,6 +411,12 @@ public object SelectionColor
             set => _selectionColor = VTColorUtils.AsEscapeSequence(value);
         }
 
+        public object PredictionColor
+        {
+            get => _predictionColor;
+            set => _predictionColor = VTColorUtils.AsEscapeSequence(value);
+        }
+
         internal string _defaultTokenColor;
         internal string _commentColor;
         internal string _keywordColor;
@@ -421,6 +431,7 @@ public object SelectionColor
         internal string _emphasisColor;
         internal string _errorColor;
         internal string _selectionColor;
+        internal string _predictionColor;
 
         internal void ResetColors()
         {
@@ -438,6 +449,7 @@ internal void ResetColors()
             MemberColor       = DefaultNumberColor;
             EmphasisColor     = DefaultEmphasisColor;
             ErrorColor        = DefaultErrorColor;
+            PredictionColor   = DefaultPredictionColor;
 
             var bg = Console.BackgroundColor;
             if (fg == VTColorUtils.UnknownColor || bg == VTColorUtils.UnknownColor)
@@ -473,7 +485,8 @@ internal void SetColor(string property, object value)
                         {"Type", (o, v) => o.TypeColor = v},
                         {"Number", (o, v) => o.NumberColor = v},
                         {"Member", (o, v) => o.MemberColor = v},
-                        {"Selection", (o, v) => o.SelectionColor = v },
+                        {"Selection", (o, v) => o.SelectionColor = v},
+                        {"Prediction", (o, v) => o.PredictionColor = v},
                     };
 
                 Interlocked.CompareExchange(ref ColorSetters, setters, null);

PSReadLine/PSReadLine.format.ps1xml

@@ -202,6 +202,10 @@ $d = [Microsoft.PowerShell.KeyHandler]::GetGroupingDescription($_.Group)
                 <Label>ParameterColor</Label>
                 <ScriptBlock>[Microsoft.PowerShell.VTColorUtils]::FormatColor($_.ParameterColor)</ScriptBlock>
               </ListItem>
+              <ListItem>
+                <Label>PredictionColor</Label>
+                <ScriptBlock>[Microsoft.PowerShell.VTColorUtils]::FormatColor($_.PredictionColor)</ScriptBlock>
+              </ListItem>
               <ListItem>
                 <Label>SelectionColor</Label>
                 <ScriptBlock>[Microsoft.PowerShell.VTColorUtils]::FormatColor($_.SelectionColor)</ScriptBlock>

PSReadLine/Render.cs

@@ -373,9 +373,7 @@ void MaybeEmphasize(int i, string currColor)
             inSelectedRegion = false;
             if (suggestion != null)
             {
-                // TODO: write suggestion out in dark black by default, but it needs to be configurable.
-                // Find the most suitable color using https://stackoverflow.com/a/33206814
-                color = "\x1b[38;5;238m";
+                color = _options._predictionColor;
                 UpdateColorsIfNecessary(color);
 
                 foreach (char charToRender in suggestion)

docs/Set-PSReadLineOption.md

@@ -389,6 +389,8 @@ The valid keys include:
 
 -- Member: The member name token color.
 
+-- Prediction: The color for the suggestion text that comes from the prediction API.
+
 ```yaml
 Type: Hashtable
 Parameter Sets: (All)