Fix sample for strict mode+better custom handler error msg

Fixes #304

Author: lzybkr

PSReadLine/Options.cs

@@ -243,13 +243,31 @@ public static PSConsoleReadlineOptions GetOptions()
             return _singleton._options;
         }
 
+        class CustomHandlerException : Exception
+        {
+            internal CustomHandlerException(Exception innerException)
+                : base("", innerException)
+            {
+            }
+        }
+
         /// <summary>
         /// Helper function for the Set-PSReadlineKeyHandler cmdlet.
         /// </summary>
         public static void SetKeyHandler(string[] key, ScriptBlock scriptBlock, string briefDescription, string longDescription)
         {
-            Action<ConsoleKeyInfo?, object> handler =
-                (k, arg) => scriptBlock.Invoke(k, arg);
+            Action<ConsoleKeyInfo?, object> handler = (k, arg) =>
+            {
+                try
+                {
+                    scriptBlock.Invoke(k, arg);
+                }
+                catch (Exception e)
+                {
+                    throw new CustomHandlerException(e);
+                }
+            };
+
             _singleton.SetKeyHandlerInternal(key, handler, briefDescription, longDescription, scriptBlock);
         }
 

PSReadLine/PSReadLineResources.Designer.cs

@@ -714,4 +714,7 @@ If there are other parse errors, unresolved commands, or incorrect parameters, s
 Or not saving history with:
     Set-PSReadlineOption -HistorySaveStyle SaveNothing</value>
   </data>
+  <data name="OopsCustomHandlerException" xml:space="preserve">
+    <value>An exception occurred in custom key handler, see $error for more information: {0}</value>
+  </data>
 </root>

PSReadLine/PSReadLineResources.resx

@@ -251,8 +251,8 @@ private bool BreakHandler(ConsoleBreakSignal signal)
         /// <returns>The complete command line.</returns>
         public static string ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsics)
         {
-            var console1 = _singleton._console;
-            _singleton._prePSReadlineConsoleMode = console1.GetConsoleInputMode();
+            var console = _singleton._console;
+            _singleton._prePSReadlineConsoleMode = console.GetConsoleInputMode();
             bool firstTime = true;
             while (true)
             {
@@ -265,11 +265,11 @@ public static string ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsi
                     //     ENABLE_MOUSE_INPUT - mouse events
                     //     ENABLE_WINDOW_INPUT - window resize events
                     var mode = _singleton._prePSReadlineConsoleMode &
-                        ~(NativeMethods.ENABLE_PROCESSED_INPUT |
-                          NativeMethods.ENABLE_LINE_INPUT |
-                          NativeMethods.ENABLE_WINDOW_INPUT |
-                          NativeMethods.ENABLE_MOUSE_INPUT);
-                    console1.SetConsoleInputMode(mode);
+                               ~(NativeMethods.ENABLE_PROCESSED_INPUT |
+                                 NativeMethods.ENABLE_LINE_INPUT |
+                                 NativeMethods.ENABLE_WINDOW_INPUT |
+                                 NativeMethods.ENABLE_MOUSE_INPUT);
+                    console.SetConsoleInputMode(mode);
 
                     if (firstTime)
                     {
@@ -288,6 +288,19 @@ public static string ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsi
                 {
                     return "exit";
                 }
+                catch (CustomHandlerException e)
+                {
+                    var oldColor = console.ForegroundColor;
+                    console.ForegroundColor = ConsoleColor.Red;
+                    console.WriteLine(
+                        string.Format(CultureInfo.CurrentUICulture, PSReadLineResources.OopsCustomHandlerException, e.InnerException.Message));
+                    console.ForegroundColor = oldColor;
+
+                    var lineBeforeCrash = _singleton._buffer.ToString();
+                    _singleton.Initialize(runspace, _singleton._engineIntrinsics);
+                    InvokePrompt();
+                    Insert(lineBeforeCrash);
+                }
                 catch (Exception e)
                 {
                     // If we're running tests, just throw.
@@ -300,7 +313,6 @@ public static string ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsi
                     {
                         e = e.InnerException;
                     }
-                    var console = console1;
                     var oldColor = console.ForegroundColor;
                     console.ForegroundColor = ConsoleColor.Red;
                     console.WriteLine(PSReadLineResources.OopsAnErrorMessage1);
@@ -318,18 +330,17 @@ public static string ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsi
                             // Make it a little easier to see the keys
                             sb.Append('\n');
                         }
-                        // TODO: print non-default function bindings and script blocks
                     }
 
                     console.WriteLine(string.Format(CultureInfo.CurrentUICulture, PSReadLineResources.OopsAnErrorMessage2, _lastNKeys.Count, sb, e));
                     var lineBeforeCrash = _singleton._buffer.ToString();
-                        _singleton.Initialize(runspace, _singleton._engineIntrinsics);
+                    _singleton.Initialize(runspace, _singleton._engineIntrinsics);
                     InvokePrompt();
                     Insert(lineBeforeCrash);
                 }
                 finally
                 {
-                    console1.SetConsoleInputMode(_singleton._prePSReadlineConsoleMode);
+                    console.SetConsoleInputMode(_singleton._prePSReadlineConsoleMode);
                 }
             }
         }

PSReadLine/ReadLine.cs

@@ -192,13 +192,16 @@ Set-PSReadlineKeyHandler -Key Backspace `
     if ($cursor -gt 0)
     {
         $toMatch = $null
-        switch ($line[$cursor])
+        if ($cursor -lt $line.Length)
         {
-            <#case#> '"' { $toMatch = '"'; break }
-            <#case#> "'" { $toMatch = "'"; break }
-            <#case#> ')' { $toMatch = '('; break }
-            <#case#> ']' { $toMatch = '['; break }
-            <#case#> '}' { $toMatch = '{'; break }
+            switch ($line[$cursor])
+            {
+                <#case#> '"' { $toMatch = '"'; break }
+                <#case#> "'" { $toMatch = "'"; break }
+                <#case#> ')' { $toMatch = '('; break }
+                <#case#> ']' { $toMatch = '['; break }
+                <#case#> '}' { $toMatch = '{'; break }
+            }
         }
 
         if ($toMatch -ne $null -and $line[$cursor-1] -eq $toMatch)