Fix console errors (#457)

* Fix console errors

* Tweaking test code

src/Microsoft.Repl/Commanding/DefaultCommandDispatcher.cs

@@ -84,7 +84,7 @@ public IReadOnlyList<string> CollectSuggestions(IShellState shellState)
             shellState = shellState ?? throw new ArgumentNullException(nameof(shellState));
 
             string line = shellState.InputManager.GetCurrentBuffer();
-            TParseResult parseResult = _parser.Parse(line, shellState.ConsoleManager.CaretPosition);
+            TParseResult parseResult = _parser.Parse(line, shellState.InputManager.CaretPosition);
             HashSet<string> suggestions = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
 
             foreach (ICommand<TProgramState, TParseResult> command in _commands)
@@ -139,7 +139,7 @@ public async Task ExecuteCommandAsync(IShellState shellState, CancellationToken
         private async Task ExecuteCommandInternalAsync(IShellState shellState, CancellationToken cancellationToken)
         {
             string line = shellState.InputManager.GetCurrentBuffer();
-            TParseResult parseResult = _parser.Parse(line, shellState.ConsoleManager.CaretPosition);
+            TParseResult parseResult = _parser.Parse(line, shellState.InputManager.CaretPosition);
 
             if (!string.IsNullOrWhiteSpace(parseResult.CommandText))
             {
@@ -171,7 +171,7 @@ public void OnReady(IShellState shellState)
             if (!_isReady && !shellState.IsExiting)
             {
                 _onReady(shellState);
-                shellState.ConsoleManager.ResetCommandStart();
+                shellState.InputManager.ResetInput();
                 _isReady = true;
             }
         }

src/Microsoft.Repl/ConsoleHandling/ConsoleManager.cs

@@ -14,17 +14,6 @@ public class ConsoleManager : IConsoleManager
 
         public Point Caret => new Point(Console.CursorLeft, Console.CursorTop);
 
-        public Point CommandStart
-        {
-            get
-            {
-                Point c = Caret;
-                return new Point(c.X - CaretPosition % Console.BufferWidth, c.Y - CaretPosition / Console.BufferWidth);
-            }
-        }
-
-        public int CaretPosition { get; private set; }
-
         public bool IsKeyAvailable => Console.KeyAvailable;
 
         public bool IsCaretVisible
@@ -35,95 +24,88 @@ public bool IsCaretVisible
 
         public ConsoleManager()
         {
-            Error = new Writable(CaretUpdateScope, Reporter.Error);
+            Error = new Writable(Reporter.Error);
             Console.CancelKeyPress += OnCancelKeyPress;
         }
 
         public void Clear()
         {
-            using (CaretUpdateScope())
-            {
-                Console.Clear();
-                ResetCommandStart();
-            }
+            Console.Clear();
         }
 
         public void MoveCaret(int positions)
         {
-            using (CaretUpdateScope())
+            if (positions == 0)
             {
-                if (positions == 0)
-                {
-                    return;
-                }
+                return;
+            }
 
-                int bufferWidth = Console.BufferWidth;
-                int cursorTop = Console.CursorTop;
-                int cursorLeft = Console.CursorLeft;
+            int bufferWidth = Console.BufferWidth;
+            int cursorTop = Console.CursorTop;
+            int cursorLeft = Console.CursorLeft;
 
-                while (positions < 0 && CaretPosition > 0)
+            while (positions < 0)
+            {
+                if (-positions > bufferWidth)
                 {
-                    if (-positions > bufferWidth)
+                    if (cursorTop == 0)
                     {
-                        if (cursorTop == 0)
-                        {
-                            cursorLeft = 0;
-                            positions = 0;
-                        }
-                        else
-                        {
-                            positions += bufferWidth;
-                            --cursorTop;
-                        }
+                        cursorLeft = 0;
+                        positions = 0;
                     }
                     else
                     {
-                        int remaining = cursorLeft + positions;
-
-                        if (remaining >= 0)
-                        {
-                            cursorLeft = remaining;
-                        }
-                        else if (cursorTop == 0)
-                        {
-                            cursorLeft = 0;
-                        }
-                        else
-                        {
-                            --cursorTop;
-                            cursorLeft = bufferWidth + remaining;
-                        }
+                        positions += bufferWidth;
+                        --cursorTop;
+                    }
+                }
+                else
+                {
+                    int remaining = cursorLeft + positions;
 
-                        positions = 0;
+                    if (remaining >= 0)
+                    {
+                        cursorLeft = remaining;
                     }
+                    else if (cursorTop == 0)
+                    {
+                        cursorLeft = 0;
+                    }
+                    else
+                    {
+                        --cursorTop;
+                        cursorLeft = bufferWidth + remaining;
+                    }
+
+                    positions = 0;
                 }
+            }
 
-                while (positions > 0)
+            while (positions > 0)
+            {
+                if (positions > bufferWidth)
+                {
+                    positions -= bufferWidth;
+                    ++cursorTop;
+                }
+                else
                 {
-                    if (positions > bufferWidth)
+                    int spaceLeftOnLine = bufferWidth - cursorLeft - 1;
+                    if (positions > spaceLeftOnLine)
                     {
-                        positions -= bufferWidth;
                         ++cursorTop;
+                        cursorLeft = positions - spaceLeftOnLine - 1;
                     }
                     else
                     {
-                        int spaceLeftOnLine = bufferWidth - cursorLeft - 1;
-                        if (positions > spaceLeftOnLine)
-                        {
-                            ++cursorTop;
-                            cursorLeft = positions - spaceLeftOnLine - 1;
-                        }
-                        else
-                        {
-                            cursorLeft += positions;
-                        }
-
-                        positions = 0;
+                        cursorLeft += positions;
                     }
-                }
 
-                Console.SetCursorPosition(cursorLeft, cursorTop);
+                    positions = 0;
+                }
             }
+
+            Console.SetCursorPosition(cursorLeft, cursorTop);
         }
 
         public ConsoleKeyInfo ReadKey(CancellationToken cancellationToken)
@@ -143,33 +125,19 @@ public ConsoleKeyInfo ReadKey(CancellationToken cancellationToken)
             }
         }
 
-        public void ResetCommandStart()
-        {
-            CaretPosition = 0;
-        }
-
         public void Write(char c)
         {
-            using (CaretUpdateScope())
-            {
-                Reporter.Output.Write(c);
-            }
+            Reporter.Output.Write(c);
         }
 
         public void Write(string s)
         {
-            using (CaretUpdateScope())
-            {
-                Reporter.Output.Write(s);
-            }
+            Reporter.Output.Write(s);
         }
 
         public void WriteLine()
         {
-            using (CaretUpdateScope())
-            {
-                Reporter.Output.WriteLine();
-            }
+            Reporter.Output.WriteLine();
         }
 
         public void WriteLine(string s)
@@ -179,10 +147,7 @@ public void WriteLine(string s)
                 return;
             }
 
-            using (CaretUpdateScope())
-            {
-                Reporter.Output.WriteLine(s);
-            }
+            Reporter.Output.WriteLine(s);
         }
 
         public IDisposable AddBreakHandler(Action onBreak)
@@ -192,18 +157,6 @@ public IDisposable AddBreakHandler(Action onBreak)
             return result;
         }
 
-        private IDisposable CaretUpdateScope()
-        {
-            Point currentCaret = Caret;
-            return new Disposable(() =>
-            {
-                Point c = Caret;
-                int y = c.Y - currentCaret.Y;
-                int x = c.X - currentCaret.X;
-                CaretPosition += y * Console.BufferWidth + x;
-            });
-        }
-
         private void OnCancelKeyPress(object sender, ConsoleCancelEventArgs e)
         {
             e.Cancel = true;

src/Microsoft.Repl/ConsoleHandling/IConsoleManager.cs

@@ -10,10 +10,6 @@ public interface IConsoleManager : IWritable
     {
         Point Caret { get; }
 
-        Point CommandStart { get; }
-
-        int CaretPosition { get; }
-
 #pragma warning disable CA1716 // Identifiers should not match keywords
         IWritable Error { get; }
 #pragma warning restore CA1716 // Identifiers should not match keywords
@@ -26,8 +22,6 @@ public interface IConsoleManager : IWritable
 
         ConsoleKeyInfo ReadKey(CancellationToken cancellationToken);
 
-        void ResetCommandStart();
-
         IDisposable AddBreakHandler(Action onBreak);
 
         bool AllowOutputRedirection { get; }

src/Microsoft.Repl/ConsoleHandling/Writable.cs

@@ -1,18 +1,14 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
-
 namespace Microsoft.Repl.ConsoleHandling
 {
     internal class Writable : IWritable
     {
-        private readonly Func<IDisposable> _caretUpdater;
         private readonly Reporter _reporter;
 
-        public Writable(Func<IDisposable> caretUpdater, Reporter reporter)
+        public Writable(Reporter reporter)
         {
-            _caretUpdater = caretUpdater;
             _reporter = reporter;
         }
 
@@ -24,34 +20,22 @@ public bool IsCaretVisible
 
         public void Write(char c)
         {
-            using (_caretUpdater())
-            {
-                _reporter.Write(c);
-            }
+            _reporter.Write(c);
         }
 
         public void Write(string s)
         {
-            using (_caretUpdater())
-            {
-                _reporter.Write(s);
-            }
+            _reporter.Write(s);
         }
 
         public void WriteLine()
         {
-            using (_caretUpdater())
-            {
-                _reporter.WriteLine();
-            }
+            _reporter.WriteLine();
         }
 
         public void WriteLine(string s)
         {
-            using (_caretUpdater())
-            {
-                _reporter.WriteLine(s);
-            }
+            _reporter.WriteLine(s);
         }
     }
 }

src/Microsoft.Repl/IShellState.cs

@@ -21,5 +21,7 @@ public interface IShellState
         ISuggestionManager SuggestionManager { get; }
 
         bool IsExiting { get; set; }
+
+        void MoveCarets(int positions);
     }
 }

src/Microsoft.Repl/Input/IInputManager.cs

@@ -11,6 +11,8 @@ public interface IInputManager
     {
         bool IsOverwriteMode { get; set; }
 
+        int CaretPosition { get; }
+
         IInputManager RegisterKeyHandler(ConsoleKey key, AsyncKeyPressHandler handler);
 
         IInputManager RegisterKeyHandler(ConsoleKey key, ConsoleModifiers modifiers, AsyncKeyPressHandler handler);
@@ -28,5 +30,7 @@ public interface IInputManager
         void RemoveCurrentCharacter(IShellState state);
 
         void Clear(IShellState state);
+
+        void MoveCaret(int positions);
     }
 }