experiments/Editor/tests/testlib.js - incubator-retired-corinthia - Git at Google

 // Licensed to the Apache Software Foundation (ASF) under one
 // or more contributor license agreements.  See the NOTICE file
 // distributed with this work for additional information
 // regarding copyright ownership.  The ASF licenses this file
 // to you under the Apache License, Version 2.0 (the
 // "License"); you may not use this file except in compliance
 // with the License.  You may obtain a copy of the License at
 //
 //   http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing,
 // software distributed under the License is distributed on an
 // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 // KIND, either express or implied.  See the License for the
 // specific language governing permissions and limitations
 // under the License.

 function testHarnessSetup()
 {
     DOM_assignNodeIds(document);

     var start;
     var track;
     var end;


     UndoManager_disableWhileExecuting(function() {
         start = extractPositionFromCharacter("[");
         track = (start == null) ? [] : [start];
         Position_trackWhileExecuting(track,function() {
             end = extractPositionFromCharacter("]");
         });
     });

     if ((start != null) && (end == null))
         throw new Error("Start of selection specified, but not end");
     if ((start == null) && (end != null))
         throw new Error("End of selection specified, but not start");

     if ((start != null) && (end != null)) {
         var range = new Range(start.node,start.offset,end.node,end.offset);

         UndoManager_disableWhileExecuting(function() {
             Range_trackWhileExecuting(range,function() {
                 positionMergeWithNeighbours(start);
                 positionMergeWithNeighbours(end);
             });
         });

         range.start = Position_preferTextPosition(range.start);
         range.end = Position_preferTextPosition(range.end);

         Selection_set(range.start.node,range.start.offset,range.end.node,range.end.offset);
     }

     return;

     function positionMergeWithNeighbours(pos)
     {
         var node = pos.node;
         var offset = pos.offset;
         if ((node.nodeType == Node.ELEMENT_NODE) && (offset < node.childNodes.length))
             Formatting_mergeWithNeighbours(node.childNodes[offset],Formatting_MERGEABLE_INLINE);
         else if ((node.nodeType == Node.ELEMENT_NODE) && (node.lastChild != null))
             Formatting_mergeWithNeighbours(node.lastChild,Formatting_MERGEABLE_INLINE);
         else
             Formatting_mergeWithNeighbours(node,Formatting_MERGEABLE_INLINE);
     }

     function extractPositionFromCharacter(c)
     {
         return recurse(document.body);

         function recurse(node)
         {
             if (node.nodeType == Node.TEXT_NODE) {
                 var index = node.nodeValue.indexOf(c);
                 if (index >= 0) {
                     var offsetInParent = DOM_nodeOffset(node);
                     if (index == 0) {
                         node.nodeValue = node.nodeValue.substring(1);
                         return new Position(node.parentNode,offsetInParent);
                     }
                     else if (index == node.nodeValue.length - 1) {
                         node.nodeValue = node.nodeValue.substring(0,node.nodeValue.length-1);
                         return new Position(node.parentNode,offsetInParent+1);
                     }
                     else {
                         var rest = node.nodeValue.substring(index+1);
                         node.nodeValue = node.nodeValue.substring(0,index);
                         var restNode = DOM_createTextNode(document,rest);
                         DOM_insertBefore(node.parentNode,restNode,node.nextSibling);
                         return new Position(node.parentNode,offsetInParent+1);
                     }
                 }
             }
             else {
                 for (var child = node.firstChild; child != null; child = child.nextSibling) {
                     var result = recurse(child);
                     if (result != null)
                         return result;
                 }
             }
             return null;
         }
     }
 }

 function insertAtPosition(position,node)
 {
     if (position.node.nodeType == Node.ELEMENT_NODE) {
         if (position.offset == position.node.childNodes.length)
             DOM_appendChild(position.node,node);
         else
             DOM_insertBefore(position.node,node,position.node.childNodes[position.offset]);
     }
     else if (position.node.nodeType == Node.TEXT_NODE) {
         var newText = DOM_createTextNode(document,position.node.nodeValue.slice(position.offset));
         position.node.nodeValue = position.node.nodeValue.slice(0,position.offset);
         DOM_insertBefore(position.node.parentNode,newText,position.node.nextSibling);
         DOM_insertBefore(position.node.parentNode,node,position.node.nextSibling);
     }
 }

 function insertTextAtPosition(position,str)
 {
     if (position.node.nodeType == Node.ELEMENT_NODE) {
         var before = position.node.childNodes[position.offset-1];
         var after = position.node.childNodes[position.offset];
         if ((after != null) && (after.nodeType == Node.TEXT_NODE))
             position = new Position(after,0);
         else if ((before != null) && (before.nodeType == Node.TEXT_NODE))
             position = new Position(before,before.nodeValue.length);
     }
     if (position.node.nodeType == Node.ELEMENT_NODE) {
         insertAtPosition(position,DOM_createTextNode(document,str));
     }
     else if (position.node.nodeType == Node.TEXT_NODE) {
         position.node.nodeValue = position.node.nodeValue.slice(0,position.offset) + str +
                                   position.node.nodeValue.slice(position.offset);
     }
 }

 function showRangeAsBrackets(range)
 {
     if (Range_isEmpty(range)) {
         insertTextAtPosition(range.end,"[]",true);
     }
     else {
         insertTextAtPosition(range.end,"]",true);
         insertTextAtPosition(range.start,"[",true);
     }
 }

 function showSelection()
 {
     var range = Selection_get();
     if (range != null) {
         Range_assertValid(range,"Selection");
         showRangeAsBrackets(range);
     }
 }

 function removeIds()
 {
     recurse(document.body);

     function recurse(node)
     {
         if (node.nodeType == Node.ELEMENT_NODE) {
             DOM_removeAttribute(node,"id");
             for (var child = node.firstChild; child != null; child = child.nextSibling)
                 recurse(child);
         }
     }
 }

 function selectNode(node)
 {
     var offset = DOM_nodeOffset(node);
     Selection_set(node.parentNode,offset,node.parentNode,offset+1);
 }

 function removeWhitespaceAndCommentNodes(root)
 {
     Selection_preserveWhileExecuting(function() {
         recurse(root);
     });

     function recurse(node)
     {
         if (isWhitespaceTextNode(node) || (node.nodeType == Node.COMMENT_NODE)) {
             DOM_deleteNode(node);
         }
         else {
             var next;
             for (var child = node.firstChild; child != null; child = next) {
                 next = child.nextSibling;
                 recurse(child);
             }
         }
     }
 }

 // selectionWrapElement() and selectionUnwrapElement() used to be in formatting.js but have
 // now been made obselete by the addition of applyFormattingChanges(). However there are still
 // a few tests which use them.
 function selectionWrapElement(elementName)
 {
     if (elementName == "B")
         Formatting_applyFormattingChanges(null,{"font-weight": "bold"});
     else if (elementName == "I")
         Formatting_applyFormattingChanges(null,{"font-style": "italic"});
     else if (elementName == "U")
         Formatting_applyFormattingChanges(null,{"text-decoration": "underline"});
 }

 function selectionUnwrapElement(elementName)
 {
     if (elementName == "B")
         Formatting_applyFormattingChanges(null,{"font-weight": null});
     else if (elementName == "I")
         Formatting_applyFormattingChanges(null,{"font-style": null});
     else if (elementName == "U")
         Formatting_applyFormattingChanges(null,{"text-decoration": null});
 }

 function showEmptyTextNodes()
 {
     recurse(document);

     function recurse(node)
     {
         if ((node.nodeType == Node.TEXT_NODE) && (node.nodeValue.length == 0))
             node.nodeValue = "*";
         for (var child = node.firstChild; child != null; child = child.nextSibling)
             recurse(child);
     }
 }

 function showClipboard(clipboard)
 {
     var html = clipboard["text/html"];
     var text = clipboard["text/plain"];

     if ((html.length == 0) || (html.charAt(html.length-1) != "\n"))
         html += "\n";
     if ((text.length == 0) || (text.charAt(text.length-1) != "\n"))
         text += "\n";

     // Chrome and Safari behave differently when generating style attribute values for innerHTML.
     // Safari adds a space after the last property definition, while chrome doesn't. For consistent
     // results, we add the space if it is not already there (this was the original behaviour
     // of Chrome but it changed).
     html = html.replace(/(style="[^"]+;)"/g,"$1 \"");

     return "text/html\n"+
            "---------\n"+
            "\n"+
            html+
            "\n"+
            "text/plain\n"+
            "----------\n"+
            "\n"+
            text;
 }

 function setNumbering(enabled)
 {
     if (enabled)
         setupOutlineNumbering();

     recurse(document.body,enabled);
     PostponedActions_perform();

     function recurse(node,enabled)
     {
         switch (node._type) {
         case HTML_H1:
         case HTML_H2:
         case HTML_H3:
         case HTML_H4:
         case HTML_H5:
         case HTML_H6:
         case HTML_FIGURE:
         case HTML_TABLE:
             if (!isInTOC(node)) {
                 Outline_setNumbered(node.getAttribute("id"),enabled);
                 return;
             }
             break;
         }

         for (var child = node.firstChild; child != null; child = child.nextSibling)
             recurse(child,enabled);
     }
 }

 function readXML(filename)
 {
     var req = new XMLHttpRequest();
     req.open("GET",filename,false);
     req.send();
     var xml = req.responseXML;
     if (xml == null)
         return null;
     DOM_assignNodeIds(xml.documentElement);
     return xml;
 }

 function findTextMatchingRecursive(node,re)
 {
     if (node.nodeType == Node.TEXT_NODE) {
         if (node.nodeValue.match(re))
             return node;
         else
             return null;
     }
     else {
         for (var child = node.firstChild; child != null; child = child.nextSibling) {
             var result = findTextMatchingRecursive(child,re);
             if (result != null)
                 return result;
         }
         return null;
     }
 }

 function setupOutlineNumbering()
 {
     Styles_setCSSText("",
     {
         "h1": {
             "counter-reset": "h2 h3 h4 h5 h6",
             "counter-increment": "h1"
         },
         "h2": {
             "counter-reset": "h3 h4 h5 h6",
             "counter-increment": "h2"
         },
         "h3": {
             "counter-reset": "h4 h5 h6",
             "counter-increment": "h3"
         },
         "h4": {
             "counter-reset": "h5 h6",
             "counter-increment": "h4"
         },
         "h5": {
             "counter-reset": "h6",
             "counter-increment": "h5"
         },
         "h6": {
             "counter-increment": "h6"
         },
         "h1::before": {
             "content": "counter(h1) ' '"
         },
         "h2::before": {
             "content": "counter(h1) '.' counter(h2) ' '"
         },
         "h3::before": {
             "content": "counter(h1) '.' counter(h2) '.' counter(h3) ' '"
         },
         "h4::before": {
             "content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) ' '"
         },
         "h5::before": {
             "content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) '.' counter(h5) ' '"
         },
         "h6::before": {
             "content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) '.' counter(h5) '.' counter(h6) ' '"
         },
     });
 }

 function prependTableOfContents()
 {
     var nav = DOM_createElement(document,"NAV");
     DOM_setAttribute(nav,"class","tableofcontents");
     DOM_insertBefore(document.body,nav,document.body.firstChild);
     PostponedActions_perform();
 }

 function simplifyTOCs()
 {
     recurse(document.body);

     function recurse(node)
     {
         if ((node._type == HTML_NAV) &&
             ((DOM_getAttribute(node,"class") == "tableofcontents") ||
              (DOM_getAttribute(node,"class") == "listoffigures") ||
              (DOM_getAttribute(node,"class") == "listoftables"))) {
             mergeAdjacentTextNodes(node);
         }
         else {
             for (var child = node.firstChild; child != null; child = child.nextSibling)
                 recurse(child);
         }
     }

     function mergeAdjacentTextNodes(node)
     {
         var child = node.firstChild;
         while (child != null) {
             if ((child.nodeType == Node.TEXT_NODE) &&
                 (child.nextSibling != null) &&
                 (child.nextSibling.nodeType == Node.TEXT_NODE)) {
                 DOM_insertCharacters(child,child.nodeValue.length,child.nextSibling.nodeValue);
                 DOM_deleteNode(child.nextSibling);
             }
             else {
                 child = child.nextSibling;
             }
         }

         for (var child = node.firstChild; child != null; child = child.nextSibling)
             mergeAdjacentTextNodes(child);
     }
 }

 function showNonEmptyTextNodes()
 {
     recurse(document.body);

     function recurse(node)
     {
         if (node.nodeType == Node.TEXT_NODE) {
             if (!isWhitespaceTextNode(node))
                 node.nodeValue = "{" + node.nodeValue + "}";
         }
         else {
             for (var child = node.firstChild; child != null; child = child.nextSibling)
                 recurse(child);
         }
     }
 }
	// Licensed to the Apache Software Foundation (ASF) under one
	// or more contributor license agreements. See the NOTICE file
	// distributed with this work for additional information
	// regarding copyright ownership. The ASF licenses this file
	// to you under the Apache License, Version 2.0 (the
	// "License"); you may not use this file except in compliance
	// with the License. You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing,
	// software distributed under the License is distributed on an
	// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	// KIND, either express or implied. See the License for the
	// specific language governing permissions and limitations
	// under the License.

	function testHarnessSetup()
	{
	DOM_assignNodeIds(document);

	var start;
	var track;
	var end;


	UndoManager_disableWhileExecuting(function() {
	start = extractPositionFromCharacter("[");
	track = (start == null) ? [] : [start];
	Position_trackWhileExecuting(track,function() {
	end = extractPositionFromCharacter("]");
	});
	});

	if ((start != null) && (end == null))
	throw new Error("Start of selection specified, but not end");
	if ((start == null) && (end != null))
	throw new Error("End of selection specified, but not start");

	if ((start != null) && (end != null)) {
	var range = new Range(start.node,start.offset,end.node,end.offset);

	UndoManager_disableWhileExecuting(function() {
	Range_trackWhileExecuting(range,function() {
	positionMergeWithNeighbours(start);
	positionMergeWithNeighbours(end);
	});
	});

	range.start = Position_preferTextPosition(range.start);
	range.end = Position_preferTextPosition(range.end);

	Selection_set(range.start.node,range.start.offset,range.end.node,range.end.offset);
	}

	return;

	function positionMergeWithNeighbours(pos)
	{
	var node = pos.node;
	var offset = pos.offset;
	if ((node.nodeType == Node.ELEMENT_NODE) && (offset < node.childNodes.length))
	Formatting_mergeWithNeighbours(node.childNodes[offset],Formatting_MERGEABLE_INLINE);
	else if ((node.nodeType == Node.ELEMENT_NODE) && (node.lastChild != null))
	Formatting_mergeWithNeighbours(node.lastChild,Formatting_MERGEABLE_INLINE);
	else
	Formatting_mergeWithNeighbours(node,Formatting_MERGEABLE_INLINE);
	}

	function extractPositionFromCharacter(c)
	{
	return recurse(document.body);

	function recurse(node)
	{
	if (node.nodeType == Node.TEXT_NODE) {
	var index = node.nodeValue.indexOf(c);
	if (index >= 0) {
	var offsetInParent = DOM_nodeOffset(node);
	if (index == 0) {
	node.nodeValue = node.nodeValue.substring(1);
	return new Position(node.parentNode,offsetInParent);
	}
	else if (index == node.nodeValue.length - 1) {
	node.nodeValue = node.nodeValue.substring(0,node.nodeValue.length-1);
	return new Position(node.parentNode,offsetInParent+1);
	}
	else {
	var rest = node.nodeValue.substring(index+1);
	node.nodeValue = node.nodeValue.substring(0,index);
	var restNode = DOM_createTextNode(document,rest);
	DOM_insertBefore(node.parentNode,restNode,node.nextSibling);
	return new Position(node.parentNode,offsetInParent+1);
	}
	}
	}
	else {
	for (var child = node.firstChild; child != null; child = child.nextSibling) {
	var result = recurse(child);
	if (result != null)
	return result;
	}
	}
	return null;
	}
	}
	}

	function insertAtPosition(position,node)
	{
	if (position.node.nodeType == Node.ELEMENT_NODE) {
	if (position.offset == position.node.childNodes.length)
	DOM_appendChild(position.node,node);
	else
	DOM_insertBefore(position.node,node,position.node.childNodes[position.offset]);
	}
	else if (position.node.nodeType == Node.TEXT_NODE) {
	var newText = DOM_createTextNode(document,position.node.nodeValue.slice(position.offset));
	position.node.nodeValue = position.node.nodeValue.slice(0,position.offset);
	DOM_insertBefore(position.node.parentNode,newText,position.node.nextSibling);
	DOM_insertBefore(position.node.parentNode,node,position.node.nextSibling);
	}
	}

	function insertTextAtPosition(position,str)
	{
	if (position.node.nodeType == Node.ELEMENT_NODE) {
	var before = position.node.childNodes[position.offset-1];
	var after = position.node.childNodes[position.offset];
	if ((after != null) && (after.nodeType == Node.TEXT_NODE))
	position = new Position(after,0);
	else if ((before != null) && (before.nodeType == Node.TEXT_NODE))
	position = new Position(before,before.nodeValue.length);
	}
	if (position.node.nodeType == Node.ELEMENT_NODE) {
	insertAtPosition(position,DOM_createTextNode(document,str));
	}
	else if (position.node.nodeType == Node.TEXT_NODE) {
	position.node.nodeValue = position.node.nodeValue.slice(0,position.offset) + str +
	position.node.nodeValue.slice(position.offset);
	}
	}

	function showRangeAsBrackets(range)
	{
	if (Range_isEmpty(range)) {
	insertTextAtPosition(range.end,"[]",true);
	}
	else {
	insertTextAtPosition(range.end,"]",true);
	insertTextAtPosition(range.start,"[",true);
	}
	}

	function showSelection()
	{
	var range = Selection_get();
	if (range != null) {
	Range_assertValid(range,"Selection");
	showRangeAsBrackets(range);
	}
	}

	function removeIds()
	{
	recurse(document.body);

	function recurse(node)
	{
	if (node.nodeType == Node.ELEMENT_NODE) {
	DOM_removeAttribute(node,"id");
	for (var child = node.firstChild; child != null; child = child.nextSibling)
	recurse(child);
	}
	}
	}

	function selectNode(node)
	{
	var offset = DOM_nodeOffset(node);
	Selection_set(node.parentNode,offset,node.parentNode,offset+1);
	}

	function removeWhitespaceAndCommentNodes(root)
	{
	Selection_preserveWhileExecuting(function() {
	recurse(root);
	});

	function recurse(node)
	{
	if (isWhitespaceTextNode(node) \|\| (node.nodeType == Node.COMMENT_NODE)) {
	DOM_deleteNode(node);
	}
	else {
	var next;
	for (var child = node.firstChild; child != null; child = next) {
	next = child.nextSibling;
	recurse(child);
	}
	}
	}
	}

	// selectionWrapElement() and selectionUnwrapElement() used to be in formatting.js but have
	// now been made obselete by the addition of applyFormattingChanges(). However there are still
	// a few tests which use them.
	function selectionWrapElement(elementName)
	{
	if (elementName == "B")
	Formatting_applyFormattingChanges(null,{"font-weight": "bold"});
	else if (elementName == "I")
	Formatting_applyFormattingChanges(null,{"font-style": "italic"});
	else if (elementName == "U")
	Formatting_applyFormattingChanges(null,{"text-decoration": "underline"});
	}

	function selectionUnwrapElement(elementName)
	{
	if (elementName == "B")
	Formatting_applyFormattingChanges(null,{"font-weight": null});
	else if (elementName == "I")
	Formatting_applyFormattingChanges(null,{"font-style": null});
	else if (elementName == "U")
	Formatting_applyFormattingChanges(null,{"text-decoration": null});
	}

	function showEmptyTextNodes()
	{
	recurse(document);

	function recurse(node)
	{
	if ((node.nodeType == Node.TEXT_NODE) && (node.nodeValue.length == 0))
	node.nodeValue = "*";
	for (var child = node.firstChild; child != null; child = child.nextSibling)
	recurse(child);
	}
	}

	function showClipboard(clipboard)
	{
	var html = clipboard["text/html"];
	var text = clipboard["text/plain"];

	if ((html.length == 0) \|\| (html.charAt(html.length-1) != "\n"))
	html += "\n";
	if ((text.length == 0) \|\| (text.charAt(text.length-1) != "\n"))
	text += "\n";

	// Chrome and Safari behave differently when generating style attribute values for innerHTML.
	// Safari adds a space after the last property definition, while chrome doesn't. For consistent
	// results, we add the space if it is not already there (this was the original behaviour
	// of Chrome but it changed).
	html = html.replace(/(style="[^"]+;)"/g,"$1 \"");

	return "text/html\n"+
	"---------\n"+
	"\n"+
	html+
	"\n"+
	"text/plain\n"+
	"----------\n"+
	"\n"+
	text;
	}

	function setNumbering(enabled)
	{
	if (enabled)
	setupOutlineNumbering();

	recurse(document.body,enabled);
	PostponedActions_perform();

	function recurse(node,enabled)
	{
	switch (node._type) {
	case HTML_H1:
	case HTML_H2:
	case HTML_H3:
	case HTML_H4:
	case HTML_H5:
	case HTML_H6:
	case HTML_FIGURE:
	case HTML_TABLE:
	if (!isInTOC(node)) {
	Outline_setNumbered(node.getAttribute("id"),enabled);
	return;
	}
	break;
	}

	for (var child = node.firstChild; child != null; child = child.nextSibling)
	recurse(child,enabled);
	}
	}

	function readXML(filename)
	{
	var req = new XMLHttpRequest();
	req.open("GET",filename,false);
	req.send();
	var xml = req.responseXML;
	if (xml == null)
	return null;
	DOM_assignNodeIds(xml.documentElement);
	return xml;
	}

	function findTextMatchingRecursive(node,re)
	{
	if (node.nodeType == Node.TEXT_NODE) {
	if (node.nodeValue.match(re))
	return node;
	else
	return null;
	}
	else {
	for (var child = node.firstChild; child != null; child = child.nextSibling) {
	var result = findTextMatchingRecursive(child,re);
	if (result != null)
	return result;
	}
	return null;
	}
	}

	function setupOutlineNumbering()
	{
	Styles_setCSSText("",
	{
	"h1": {
	"counter-reset": "h2 h3 h4 h5 h6",
	"counter-increment": "h1"
	},
	"h2": {
	"counter-reset": "h3 h4 h5 h6",
	"counter-increment": "h2"
	},
	"h3": {
	"counter-reset": "h4 h5 h6",
	"counter-increment": "h3"
	},
	"h4": {
	"counter-reset": "h5 h6",
	"counter-increment": "h4"
	},
	"h5": {
	"counter-reset": "h6",
	"counter-increment": "h5"
	},
	"h6": {
	"counter-increment": "h6"
	},
	"h1::before": {
	"content": "counter(h1) ' '"
	},
	"h2::before": {
	"content": "counter(h1) '.' counter(h2) ' '"
	},
	"h3::before": {
	"content": "counter(h1) '.' counter(h2) '.' counter(h3) ' '"
	},
	"h4::before": {
	"content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) ' '"
	},
	"h5::before": {
	"content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) '.' counter(h5) ' '"
	},
	"h6::before": {
	"content": "counter(h1) '.' counter(h2) '.' counter(h3) '.' counter(h4) '.' counter(h5) '.' counter(h6) ' '"
	},
	});
	}

	function prependTableOfContents()
	{
	var nav = DOM_createElement(document,"NAV");
	DOM_setAttribute(nav,"class","tableofcontents");
	DOM_insertBefore(document.body,nav,document.body.firstChild);
	PostponedActions_perform();
	}

	function simplifyTOCs()
	{
	recurse(document.body);

	function recurse(node)
	{
	if ((node._type == HTML_NAV) &&
	((DOM_getAttribute(node,"class") == "tableofcontents") \|\|
	(DOM_getAttribute(node,"class") == "listoffigures") \|\|
	(DOM_getAttribute(node,"class") == "listoftables"))) {
	mergeAdjacentTextNodes(node);
	}
	else {
	for (var child = node.firstChild; child != null; child = child.nextSibling)
	recurse(child);
	}
	}

	function mergeAdjacentTextNodes(node)
	{
	var child = node.firstChild;
	while (child != null) {
	if ((child.nodeType == Node.TEXT_NODE) &&
	(child.nextSibling != null) &&
	(child.nextSibling.nodeType == Node.TEXT_NODE)) {
	DOM_insertCharacters(child,child.nodeValue.length,child.nextSibling.nodeValue);
	DOM_deleteNode(child.nextSibling);
	}
	else {
	child = child.nextSibling;
	}
	}

	for (var child = node.firstChild; child != null; child = child.nextSibling)
	mergeAdjacentTextNodes(child);
	}
	}

	function showNonEmptyTextNodes()
	{
	recurse(document.body);

	function recurse(node)
	{
	if (node.nodeType == Node.TEXT_NODE) {
	if (!isWhitespaceTextNode(node))
	node.nodeValue = "{" + node.nodeValue + "}";
	}
	else {
	for (var child = node.firstChild; child != null; child = child.nextSibling)
	recurse(child);
	}
	}
	}