Index: src/sdk/cbeditor.cpp
===================================================================
--- src/sdk/cbeditor.cpp    (revision 4827)
+++ src/sdk/cbeditor.cpp    (working copy)
@@ -296,6 +296,9 @@
     int m_LastMarginMenuLine;
     int m_LastDebugLine;
 
+    bool mFoldingLimit;
+    int mFoldingLimitLevel;
+
     wxFontEncoding m_encoding;
     bool m_useByteOrderMark;
     int m_byteOrderMarkLength;
@@ -854,6 +857,10 @@
         SetEditorTitle(m_Shortname);
     }
 
+    // Folding properties.
+    m_pData->mFoldingLimit = mgr->ReadBool(_T("/folding/limit"), false);
+    m_pData->mFoldingLimitLevel = mgr->ReadInt(_T("/folding/limit_level"), 1);
+
     // EOL properties
     m_pData->m_strip_trailing_spaces = mgr->ReadBool(_T("/eol/strip_trailing_spaces"), true);
     m_pData->m_ensure_final_line_end = mgr->ReadBool(_T("/eol/ensure_final_line_end"), true);
@@ -1549,27 +1556,31 @@
         cbAssert(m_pControl2);
     cbStyledTextCtrl* ctrl = GetControl();
     int level = ctrl->GetFoldLevel(line);
+
+    // The fold parameter is the type of folding action requested
+    // 0 = Unfold; 1 = Fold; 2 = Toggle folding.
+
+    // Check if the line is a header (fold point).
     if (level & wxSCI_FOLDLEVELHEADERFLAG)
     {
-        bool expand = false;
-        if (fold == 2) // toggle
-        {
-            ctrl->ToggleFold(line);
-            return true;
-        }
-        else
-            expand = fold == 0;
-        bool IsCurLineFolded = ctrl->GetFoldExpanded(line);
-        /* -------------------------------------------------------
-        *  fold = 0 (Unfold), 1 (fold), 2 (toggle)
-        *  So check if fold = 0 then GetFoldExpanded(line) = false
-        *  before toggling it and vice-versa
-        *  -----------------------------------------------------*/
-        if ((!IsCurLineFolded && expand) || (IsCurLineFolded && !expand))
-        {
-            ctrl->ToggleFold(line);
-            return true;
-        }
+        bool IsExpanded = ctrl->GetFoldExpanded(line);
+
+        // If a fold/unfold request is issued when the block is already
+        // folded/unfolded, ignore the request.
+        if (fold == 0 && IsExpanded) return true;
+        if (fold == 1 && !IsExpanded) return true;
+
+        // Apply the folding level limit only if the current block will be
+        // folded (that means it's currently expanded), folding level limiter
+        // must be enabled of course. Unfolding will not be affected.
+        if (m_pData->mFoldingLimit && IsExpanded)
+        {
+            if ((level & wxSCI_FOLDLEVELNUMBERMASK) > (wxSCI_FOLDLEVELBASE + m_pData->mFoldingLimitLevel-1))
+                return false;
+        }
+
+        ctrl->ToggleFold(line);
+        return true;
     }
     return false;
 }
Index: src/sdk/editorconfigurationdlg.cpp
===================================================================
--- src/sdk/editorconfigurationdlg.cpp    (revision 4827)
+++ src/sdk/editorconfigurationdlg.cpp    (working copy)
@@ -162,7 +162,9 @@
        XRCCTRL(*this, "chkFoldXml", wxCheckBox)->SetValue(cfg->ReadBool(_T("/folding/fold_xml"), true));
        XRCCTRL(*this, "chkUnderlineFoldedLine", wxCheckBox)->SetValue(cfg->ReadBool(_T("/folding/underline_folded_line"), true));
     XRCCTRL(*this, "lstIndicators", wxChoice)->SetSelection(cfg->ReadInt(_T("/folding/indicator"), 2));
-
+    XRCCTRL(*this, "chkFoldLimit", wxCheckBox)->SetValue(cfg->ReadBool(_T("/folding/limit"), false));
+    XRCCTRL(*this, "spnFoldLimitLevel", wxSpinCtrl)->SetValue(cfg->ReadInt(_T("/folding/limit_level"), 1));
+    
     //gutter
     wxColour gutterColour = cfg->ReadColour(_T("/gutter/colour"), *wxLIGHT_GREY);
     XRCCTRL(*this, "lstGutterMode", wxChoice)->SetSelection(cfg->ReadInt(_T("/gutter/mode"), 0));
@@ -902,6 +904,8 @@
         cfg->Write(_T("/folding/fold_xml"),             XRCCTRL(*this, "chkFoldXml", wxCheckBox)->GetValue());
         cfg->Write(_T("/folding/underline_folded_line"), XRCCTRL(*this, "chkUnderlineFoldedLine", wxCheckBox)->GetValue());
         cfg->Write(_T("/folding/indicator"),             XRCCTRL(*this, "lstIndicators", wxChoice)->GetSelection());
+        cfg->Write(_T("/folding/limit"),                 XRCCTRL(*this, "chkFoldLimit", wxCheckBox)->GetValue());
+        cfg->Write(_T("/folding/limit_level"),             XRCCTRL(*this, "spnFoldLimitLevel", wxSpinCtrl)->GetValue());
 
         //eol
         cfg->Write(_T("/show_eol"),                     XRCCTRL(*this, "chkShowEOL", wxCheckBox)->GetValue());
Index: src/sdk/resources/editor_configuration.xrc
===================================================================
--- src/sdk/resources/editor_configuration.xrc    (revision 4827)
+++ src/sdk/resources/editor_configuration.xrc    (working copy)
@@ -445,6 +445,28 @@
                                     <flag>wxALL|wxEXPAND|wxALIGN_LEFT|wxALIGN_TOP</flag>
                                     <border>5</border>
                                 </object>
+
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