From 5c1e6835683d4daa2d0cc7c8f68972d55b2ab743 Mon Sep 17 00:00:00 2001
From: Andrey Semashev <andrey.semashev@gmail.com>
Date: Sun, 28 Apr 2024 15:18:27 +0300
Subject: [PATCH] Fix duplicate equal signs in Doxygen-generated enum value
 initializers.

Doxygen 1.9.1 generates enum <initializer> tags with text starting with
an equal sign ('=') followed by the enum value initializer. This sign
was copied under the BoostBook <default> tag, and BoostBook styleseets
add an equal sign of their own when converting this tag to HTML. This
resulted in duplicate equal signs in the HTML output.

This commit strips the leading equal sign from the initializer before
putting it into the <default> tag.
---
 xsl/doxygen/doxygen2boostbook.xsl | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/xsl/doxygen/doxygen2boostbook.xsl b/xsl/doxygen/doxygen2boostbook.xsl
index 39dd72d..097a0fd 100644
--- a/xsl/doxygen/doxygen2boostbook.xsl
+++ b/xsl/doxygen/doxygen2boostbook.xsl
@@ -324,7 +324,8 @@
 
           <xsl:if test="initializer">
             <default>
-              <xsl:apply-templates select="initializer/*|initializer/text()" mode="passthrough"/>
+              <xsl:apply-templates select="initializer/*|initializer/text()"
+                mode="enumvalue.initializer"/>
             </default>
           </xsl:if>
 
@@ -336,6 +337,24 @@
     </xsl:choose>
   </xsl:template>
 
+  <xsl:template match="text()" mode="enumvalue.initializer">
+    <!-- Remove the leading '=' sign from enum value initializers, the '='
+         character will be added later, by the templates processing <default>
+         tags. -->
+    <xsl:choose>
+      <xsl:when test="starts-with(normalize-space(string(.)), '=')">
+        <xsl:value-of select="normalize-space(substring-after(string(.), '='))"/>
+      </xsl:when>
+      <xsl:otherwise>
+        <xsl:copy-of select="."/>
+      </xsl:otherwise>
+    </xsl:choose>
+  </xsl:template>
+
+  <xsl:template match="*" mode="enumvalue.initializer">
+    <xsl:apply-templates mode="passthrough"/>
+  </xsl:template>
+
   <xsl:template name="doxygen.include.header.rec">
     <xsl:param name="name"/>
     <xsl:param name="header-list" select="$boost.doxygen.headers"/>