xsl:strip-space combined with xsl:text messes up automatic indentation - xslt

Question

Using XSLT 1.0 I would like to comment out certain XML elements and replace other XML elements, while keeping the XML nicely formatted.
For example, the following XML document
<doc>
<e1>foo</e1>
<e2>bar</e2>
</doc>
should be converted to
<doc>
<!--<e1>foo</e1>-->
<e3>foobar</e3>
<e4>foobar</e4>
</doc>
I am using the following XSL transformation and xsltproc for testing it:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:strip-space elements="*" />
<xsl:output indent="yes" />
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*" />
</xsl:copy>
</xsl:template>
<xsl:template match="e1">
<xsl:text disable-output-escaping="yes"><!--</xsl:text> <!--*-->
<xsl:copy>
<xsl:apply-templates />
</xsl:copy>
<xsl:text disable-output-escaping="yes">--></xsl:text> <!--*-->
</xsl:template>
<xsl:template match="e2">
<e3>foobar</e3><e4>foobar</e4>
</xsl:template>
</xsl:stylesheet>
But what I get is this:
<doc><!--<e1>foo</e1>--><e3>foobar</e3><e4>foobar</e4></doc>
The problem seems to be caused by the lines marked with '*' in my transformation; more specifically from inserting <!-- and -->. When I remove these two elements, the result is indented as expected.
Is there a way to wrap elements in comments while still keeping the output document nicely formatted?

Answer 1

Try whether outputting a comment with the serialization of the element, as in
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="1.0">
<xsl:import href="http://lenzconsulting.com/xml-to-string/xml-to-string.xsl"/>
<xsl:strip-space elements="*"/>
<xsl:output indent="yes"/>
<xsl:template match="/">
<xsl:apply-templates/>
</xsl:template>
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*" />
</xsl:copy>
</xsl:template>
<xsl:template match="e1">
<xsl:comment>
<xsl:call-template name="xml-to-string"></xsl:call-template>
</xsl:comment>
</xsl:template>
<xsl:template match="e2">
<e3>foobar</e3><e4>foobar</e4>
</xsl:template>
</xsl:stylesheet>
gives you a better result.