Strip leading and trailing whitespace from all <p> tags.

[homepage.git] / layouts / default.xsl

diff --git a/layouts/default.xsl b/layouts/default.xsl
index 2af8dc264ef345e2b3c17bac443a8c30c79eec56..020d1fdc61bd89728a910eb97587f052345eaf89 100644 (file)
--- a/layouts/default.xsl
+++ b/layouts/default.xsl
@@ -1,8 +1,8 @@
 <?xml version='1.0' encoding='UTF-8' ?>
 <!--
-  Nick's web site: Final XHTML output stage
+  Nick's web site: XHTML output stage
 
-  Copyright © 2018 Nick Bowler
+  Copyright © 2018-2019 Nick Bowler
 
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -26,11 +26,11 @@
   extension-element-prefixes='func f'
   exclude-result-prefixes='xhtml'>
 
+<xsl:import href='layouts/functions.xsl' />
+
 <xsl:output method='xml' encoding='UTF-8' indent='yes'
   doctype-public='-//W3C//DTD XHTML 1.1//EN'
   doctype-system='http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd' />
-<xsl:strip-space elements='*' />
-<xsl:preserve-space elements='xhtml:p' />
 
 <xsl:param name='source-uri'
   select='"//git.draconx.ca/gitweb/homepage.git/blob/"' />
@@ -47,6 +47,67 @@
   <xsl:copy><xsl:apply-templates select='node()|@*' /></xsl:copy>
 </xsl:template>
 
+<!--
+  Nokogiri's pretty-printer is a bit weird.  Regardless of the indentation
+  setting, if an element has no child text nodes then it will be pretty-
+  printed.  This works by adding arbitrary whitespace to that element, and
+  then all of its children are eligible to be pretty-printed.
+
+  If an element has any text nodes at all, then it is not pretty-printed and
+  neither are any of its descendents.
+
+  Adding arbitrary whitespace to <pre> is bad, so we inject zero-width non-
+  breaking spaces to prevent this.  This will render fine but the spaces
+  should be removed before final output to avoid problems with copy+paste.
+-->
+<xsl:template match='xhtml:pre'>
+  <xsl:copy>
+    <xsl:apply-templates select='node()|@*' />
+    <xsl:text>&#x2060;</xsl:text>
+  </xsl:copy>
+</xsl:template>
+
+<!--
+  Likewise, adding spaces between consecutive span-level elements where
+  none existed before won't go over well.
+-->
+<xsl:template name='glue-preceding-span'>
+  <xsl:if test='f:element-is-span(preceding-sibling::node()[1])'>
+    <xsl:text>&#x2060;</xsl:text>
+  </xsl:if>
+</xsl:template>
+
+<xsl:template match='*[f:element-is-span()]'>
+  <xsl:call-template name='glue-preceding-span' />
+  <xsl:copy>
+    <xsl:apply-templates select='node()|@*' />
+    <xsl:text>&#x2060;</xsl:text> <!-- avoid breaking within a span element -->
+  </xsl:copy>
+</xsl:template>
+
+<!--
+  Manually strip whitespace-only text nodes so the pretty printer can do its
+  thing on remaining elements.
+-->
+<xsl:template match='text()[normalize-space(.) = ""]'>
+  <xsl:choose>
+    <!-- preserve anything according to xml:space -->
+    <xsl:when test='ancestor::*[@xml:space][1][@xml:space="preserve"]'>
+      <xsl:copy />
+    </xsl:when>
+    <!-- preserve anything under <pre> -->
+    <xsl:when test='ancestor::xhtml:pre'><xsl:copy /></xsl:when>
+  </xsl:choose>
+</xsl:template>
+
+<!-- Clean up whitespace where harmless to do so -->
+<xsl:template match='xhtml:p/node()[1][self::text()]'>
+  <xsl:value-of select='f:strip-leading()' />
+</xsl:template>
+<xsl:template match='xhtml:p/node()[position()=last()][self::text()]'>
+  <xsl:value-of select='f:strip-trailing()' />
+</xsl:template>
+
 <!-- Add rel attributes to external links -->
 <xsl:template match='xhtml:a[starts-with(@href,"http://")
                           or starts-with(@href,"https://")