richedit: Only notify selection change when selection has actually changed from…

dlls/riched20/caret.c

@@ -1330,7 +1330,15 @@ void ME_SendSelChange(ME_TextEditor *editor)
     sc.seltyp |= SEL_TEXT;
   if (sc.chrg.cpMin < sc.chrg.cpMax+1) /* wth were RICHEDIT authors thinking ? */
     sc.seltyp |= SEL_MULTICHAR;
-  SendMessageW(GetParent(editor->hWnd), WM_NOTIFY, sc.nmhdr.idFrom, (LPARAM)&sc);
+  TRACE("cpMin=%d cpMax=%d seltyp=%d (%s %s)\n",
+    sc.chrg.cpMin, sc.chrg.cpMax, sc.seltyp,
+    (sc.seltyp & SEL_TEXT) ? "SEL_TEXT" : "",
+    (sc.seltyp & SEL_MULTICHAR) ? "SEL_MULTICHAR" : "");
+  if (sc.chrg.cpMin != editor->notified_cr.cpMin || sc.chrg.cpMax != editor->notified_cr.cpMax)
+  {
+    editor->notified_cr = sc.chrg;
+    SendMessageW(GetParent(editor->hWnd), WM_NOTIFY, sc.nmhdr.idFrom, (LPARAM)&sc);
+  }
 }
 
 BOOL

dlls/riched20/editor.c

@@ -1665,6 +1665,8 @@ ME_TextEditor *ME_MakeEditor(HWND hWnd) {
   else
     ed->cPasswordMask = 0;
   
+  ed->notified_cr.cpMin = ed->notified_cr.cpMax = 0;
+
   return ed;
 }
 

dlls/riched20/editstr.h

@@ -331,6 +331,9 @@ typedef struct tagME_TextEditor
   /*for IME */
   int imeStartIndex;
   DWORD selofs, linesel, sely;
+
+  /* Track previous notified selection */
+  CHARRANGE notified_cr;
 } ME_TextEditor;
 
 typedef struct tagME_Context