Fix underscore token parsing

StabilityMatrix.Avalonia/Behaviors/TextEditorCompletionBehavior.cs

@@ -123,7 +123,7 @@ public class TextEditorCompletionBehavior : Behavior<TextEditor>
     {
         if (completionWindow is null) return;
         
-        Dispatcher.UIThread.Post(() =>
+        /*Dispatcher.UIThread.Post(() =>
         {
             // When completion window is open, parse and update token offsets
             if (GetCaretToken(textEditor) is not { } tokenSegment)
@@ -134,7 +134,7 @@ public class TextEditorCompletionBehavior : Behavior<TextEditor>
 
             completionWindow.StartOffset = tokenSegment.Offset;
             completionWindow.EndOffset = tokenSegment.EndOffset;
-        });
+        });*/
 
         /*if (e.Text?.Length > 0) {
             if (!char.IsLetterOrDigit(e.Text[0])) {
@@ -147,6 +147,11 @@ public class TextEditorCompletionBehavior : Behavior<TextEditor>
         // We still want to insert the character that was typed.
     }
 
+    private static bool IsCompletionChar(char c)
+    {
+        return char.IsLetterOrDigit(c) || c == '_' || c == '-';
+    }
+    
     /// <summary>
     /// Gets a segment of the token the caret is currently in.
     /// </summary>
@@ -157,13 +162,13 @@ public class TextEditorCompletionBehavior : Behavior<TextEditor>
         // Search for the start and end of a token
         // A token is defined as either alphanumeric chars or a space
         var start = caret;
-        while (start > 0 && char.IsLetterOrDigit(textEditor.Document.GetCharAt(start - 1)))
+        while (start > 0 && IsCompletionChar(textEditor.Document.GetCharAt(start - 1)))
         {
             start--;
         }
         
         var end = caret;
-        while (end < textEditor.Document.TextLength && char.IsLetterOrDigit(textEditor.Document.GetCharAt(end)))
+        while (end < textEditor.Document.TextLength && IsCompletionChar(textEditor.Document.GetCharAt(end)))
         {
             end++;
         }

StabilityMatrix.Avalonia/Controls/CodeCompletion/CompletionList.cs

@@ -122,7 +122,7 @@ public class CompletionList : TemplatedControl
     }
 
     /// <summary>
-    /// Gets or sets the array of keys that are supposed to request insertation of the completion
+    /// Gets or sets the array of keys that request insertion of the completion
     /// </summary>
     public Key[] CompletionAcceptKeys { get; set; }
 
@@ -187,7 +187,8 @@ public class CompletionList : TemplatedControl
                 _listBox.SelectIndex(_listBox.ItemCount - 1);
                 break;
             default:
-                if (CompletionAcceptKeys.Contains(e.Key) && CurrentList.Count > 0)
+                // Check insertion keys
+                if (CompletionAcceptKeys.Contains(e.Key) && CurrentList?.Count > 0)
                 {
                     e.Handled = true;
                     RequestInsertion(e);

StabilityMatrix.Avalonia/Controls/CodeCompletion/CompletionWindow.axaml.cs

@@ -43,6 +43,11 @@ public class CompletionWindow : CompletionWindowBase
     private PopupWithCustomPosition? _toolTip;
     private ContentControl? _toolTipContent;
     
+    /// <summary>
+    /// Max number of items in the completion list.
+    /// </summary>
+    public int MaxListLength { get; set; } = 40;
+    
     /// <summary>
     /// Gets the completion list used in this completion window.
     /// </summary>
@@ -254,22 +259,41 @@ public class CompletionWindow : CompletionWindowBase
                 Debug.WriteLine("CaretPositionChanged newText: " + newText);
                 
                 // CompletionList.SelectItem(newText);
-
                 Dispatcher.UIThread.Post(() => UpdateQuery(newText));
+                // UpdateQuery(newText);
                 
                 IsVisible = CompletionList.ListBox!.ItemCount != 0;
             }
         }
     }
 
+    private string? lastSearchTerm;
+    private int lastCompletionLength;
+    
     /// <summary>
     /// Update the completion window's current search term.
     /// </summary>
     public void UpdateQuery(string searchTerm)
     {
-        var results = completionProvider.GetCompletions(searchTerm, 30, true);
+        // Fast path if the search term starts with the last search term
+        // and the last completion count was less than the max list length
+        // (such we won't get new results by searching again)
+        if (lastSearchTerm is not null 
+            && searchTerm.StartsWith(lastSearchTerm) 
+            && lastCompletionLength < MaxListLength)
+        {
+            CompletionList.SelectItem(searchTerm);
+            lastSearchTerm = searchTerm;
+            return;
+        }
+        
+        var results = completionProvider.GetCompletions(searchTerm, MaxListLength, true);
         CompletionList.CompletionData.Clear();
         CompletionList.CompletionData.AddRange(results);
+        
         CompletionList.SelectItem(searchTerm, true);
+        
+        lastSearchTerm = searchTerm;
+        lastCompletionLength = CompletionList.CompletionData.Count;
     }
 }