PossibleCompletions fixes

Fixes to PossibleCompletions:

  * Truncate when list item/tooltip has `n
  * Prompt when too many (default 100) completions
  * Add option to configure how many completions before prompting

Author: lzybkr

PSReadLine/Cmdlets.cs

@@ -49,6 +49,8 @@ public class PSConsoleReadlineOptions
 
         public const int DefaultDingDuration = 50;
 
+        public const int DefaultCompletionQueryItems = 100;
+
         /// <summary>
         /// When ringing the bell, what should be done?
         /// </summary>
@@ -70,6 +72,7 @@ public PSConsoleReadlineOptions()
             DingDuration = DefaultDingDuration;
             DingTone = DefaultDingTone;
             BellStyle = DefaultBellStyle;
+            CompletionQueryItems = DefaultCompletionQueryItems;
         }
 
         public string ContinuationPrompt { get; set; }
@@ -100,6 +103,7 @@ public PSConsoleReadlineOptions()
         public bool HistorySearchCursorMovesToEnd { get; set; }
         public bool ShowToolTips { get; set; }
         public int DingTone { get; set; }
+        public int CompletionQueryItems { get; set; }
 
         /// <summary>
         /// When ringing the bell, how long (in ms)?
@@ -329,6 +333,14 @@ public BellStyle BellStyle
         }
         internal BellStyle? _bellStyle;
 
+        [Parameter(ParameterSetName = "OptionsSet")]
+        public int CompletionQueryItems
+        {
+            get { return _completionQueryItems.GetValueOrDefault(); }
+            set { _completionQueryItems = value; }
+        }
+        internal int? _completionQueryItems;
+
         [Parameter(ParameterSetName = "ColorSet", Position = 0, Mandatory = true)]
         public TokenClassification TokenKind
         {

PSReadLine/PSReadLineResources.Designer.cs

@@ -249,4 +249,7 @@
   <data name="ReplacementLengthTooBig" xml:space="preserve">
     <value>length is too big</value>
   </data>
+  <data name="DisplayAllPossibilities" xml:space="preserve">
+    <value>Display all {0} possibilities? (y or n)</value>
+  </data>
 </root>

PSReadLine/PSReadLineResources.resx

@@ -6,6 +6,7 @@
 using System.Management.Automation;
 using System.Management.Automation.Language;
 using System.Text;
+using System.Text.RegularExpressions;
 
 namespace PSConsoleUtilities
 {
@@ -1113,16 +1114,32 @@ public static void PossibleCompletions(ConsoleKeyInfo? key = null, object arg =
             var coords = _singleton.ConvertOffsetToCoordinates(_singleton._buffer.Length);
             _singleton.PlaceCursor(0, coords.Y + 1);
 
+            if (completions.CompletionMatches.Count >= _singleton._options.CompletionQueryItems)
+            {
+                if (!PromptYesOrNo(string.Format(PSReadLineResources.DisplayAllPossibilities, completions.CompletionMatches.Count)))
+                {
+                    _singleton.PlaceCursor(0, coords.Y + 1);
+                    WriteLine("");
+                    _singleton.PlaceCursor(coords.X, coords.Y);
+                    return;
+                }
+            }
+
             var sb = new StringBuilder();
-            var minColWidth = completions.CompletionMatches.Max(c => c.ListItemText.Length);
+            var matches = completions.CompletionMatches.Select(
+                completion =>
+                new {ListItemText = Regex.Replace(completion.ListItemText, "\n.*", "..."),
+                     ToolTip = Regex.Replace(completion.ToolTip, "\n.*", "...")})
+                               .ToArray();
+            var minColWidth = matches.Max(c => c.ListItemText.Length);
             minColWidth += 2;
 
             if (_singleton.Options.ShowToolTips)
             {
                 const string seperator = "- ";
                 var maxTooltipWidth = Console.BufferWidth - minColWidth - seperator.Length;
 
-                foreach (var match in completions.CompletionMatches)
+                foreach (var match in matches)
                 {
                     sb.Append(match.ListItemText);
                     var spacesNeeded = minColWidth - match.ListItemText.Length;
@@ -1148,9 +1165,9 @@ public static void PossibleCompletions(ConsoleKeyInfo? key = null, object arg =
                     for (var col = 0; col < displayColumns; col++)
                     {
                         var index = row + (displayRows * col);
-                        if (index >= completions.CompletionMatches.Count)
+                        if (index >= matches.Length)
                             break;
-                        var item = completions.CompletionMatches[index].ListItemText;
+                        var item = matches[index].ListItemText;
                         sb.Append(item);
                         sb.Append(' ', minColWidth - item.Length);
                     }
@@ -2070,7 +2087,7 @@ public static void Ding()
         // The unit test framework redirects stdout - so it would see Console.WriteLine calls.
         // Unfortunately, we are testing exact placement of characters on the screen, so redirection
         // doesn't work for us.
-        static private void WriteLine(string s)
+        static private void WriteImpl(string s)
         {
             Debug.Assert(s.Length <= Console.BufferWidth);
 
@@ -2097,10 +2114,37 @@ static private void WriteLine(string s)
                                   Right = (short) s.Length
                               };
             NativeMethods.WriteConsoleOutput(handle, buffer, bufferSize, bufferCoord, ref writeRegion);
+        }
+
+        static private void WriteLine(string s)
+        {
+            Debug.Assert(s.Length <= Console.BufferWidth);
+
+            var spaces = Console.BufferWidth - s.Length;
+            if (spaces > 0)
+            {
+                s = s + new string(' ', spaces);
+            }
+            WriteImpl(s);
 
             _singleton.PlaceCursor(0, Console.CursorTop + 1);
         }
 
+        static private void Write(string s)
+        {
+            WriteImpl(s);
+
+            _singleton.PlaceCursor(s.Length, Console.CursorTop);
+        }
+
+        static private bool PromptYesOrNo(string s)
+        {
+            Write(s);
+
+            var key = ReadKey();
+            return key.Key == ConsoleKey.Y;
+        }
+
         private void RenderDemoWindow(int windowStart)
         {
             int i;
@@ -2344,6 +2388,10 @@ private void SetOptionsInternal(SetPSReadlineOption options)
             {
                 Options.BellStyle = options.BellStyle;
             }
+            if (options._completionQueryItems.HasValue)
+            {
+                Options.CompletionQueryItems = options.CompletionQueryItems;
+            }
             if (options.ResetTokenColors)
             {
                 Options.ResetColors();