fix(developer): use richedit in debug memo to support Egyptian cartou…

…ches

RichEdit allows text selection one character past end-of-string, so we
need to cater for that as well in passing text ranges to the character
grid.

Fixes: #12454

developer/src/common/delphi/components/KeymanDeveloperDebuggerMemo.pas

@@ -1,18 +1,18 @@
 (*
   Name:             KeymanDeveloperDebuggerMemo
   Copyright:        Copyright (C) 2003-2017 SIL International.
-  Documentation:    
-  Description:      
+  Documentation:
+  Description:
   Create Date:      8 Jun 2012
 
   Modified Date:    8 Jun 2012
   Authors:          mcdurdin
-  Related Files:    
-  Dependencies:     
+  Related Files:
+  Dependencies:
 
-  Bugs:             
-  Todo:             
-  Notes:            
+  Bugs:
+  Todo:
+  Notes:
   History:          08 Jun 2012 - mcdurdin - I3323 - V9.0 - Extract debug-related code TPlus-Memo into subclass
 *)
 unit KeymanDeveloperDebuggerMemo;  // I3323
@@ -24,6 +24,7 @@ interface
   Winapi.Messages,
   Winapi.Windows,
   Vcl.Controls,
+  Vcl.ComCtrls,
   Vcl.StdCtrls;
 
 type
@@ -34,7 +35,7 @@   TMemoSelection = record
     Anchor: Integer;
   end;
 
-  TKeymanDeveloperDebuggerMemo = class(TMemo)
+  TKeymanDeveloperDebuggerMemo = class(TRichEdit)
   private
     FOnMessage: TKeymanDeveloperDebuggerMessageEvent;
     FAllowUnicodeInput: Boolean;
@@ -77,6 +78,7 @@ constructor TKeymanDeveloperDebuggerMemo.Create(AOwner: TComponent);
 begin
   FAllowUnicodeInput := True;
   inherited Create(AOwner);
+  PlainText := True;
 end;
 
 procedure TKeymanDeveloperDebuggerMemo.CreateHandle;

developer/src/tike/child/Keyman.Developer.UI.Debug.UfrmLdmlKeyboardDebug.pas

@@ -831,12 +831,22 @@ procedure TfrmLdmlKeyboardDebug.memoSelMove(Sender: TObject);
 end;
 
 procedure TfrmLdmlKeyboardDebug.UpdateCharacterGrid;   // I4808
+var
+  start, len: Integer;
 begin
   if csDestroying in ComponentState then
     Exit;
 
-  TCharacterGridRenderer.Fill(sgChars, memo.Text, FDeadkeys, memo.SelStart,
-    memo.SelLength, memo.Selection.Anchor, True);
+  start := memo.SelStart;
+  len := memo.SelLength;
+  if start + len > Length(memo.Text) then
+  begin
+    // RichEdit has a virtual final character, which is selected when
+    // pressing Ctrl+A, etc.
+    len := Length(memo.Text) - start;
+  end;
+  TCharacterGridRenderer.Fill(sgChars, memo.Text, FDeadkeys, start, len
+    memo.Selection.Anchor, True);
   TCharacterGridRenderer.Size(sgChars, memo.Font);
 end;
 

developer/src/tike/child/UfrmDebug.pas

@@ -1354,11 +1354,22 @@ procedure TfrmDebug.memoSelMove(Sender: TObject);
 end;
 
 procedure TfrmDebug.UpdateCharacterGrid;   // I4808
+var
+  start, len: Integer;
 begin
   if csDestroying in ComponentState then
     Exit;
 
-  TCharacterGridRenderer.Fill(sgChars, memo.Text, FDeadkeys, memo.SelStart, memo.SelLength, memo.Selection.Anchor);
+  start := memo.SelStart;
+  len := memo.SelLength;
+  if start + len > Length(memo.Text) then
+  begin
+    // RichEdit has a virtual final character, which is selected when
+    // pressing Ctrl+A, etc.
+    len := Length(memo.Text) - start;
+  end;
+
+  TCharacterGridRenderer.Fill(sgChars, memo.Text, FDeadkeys, start, len, memo.Selection.Anchor);
   TCharacterGridRenderer.Size(sgChars, memo.Font);
 end;