From a62d155eb02f5ed7c41397362480300c5ab20d55 Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mike.gerwitz@rtspecialty.com>
Date: Thu, 4 Jan 2018 11:05:58 -0500
Subject: [PATCH] Resolve lv:param-add/@value before processing

* src/current/include/preproc/template.xsl
  (preproc:gen-param-value)[lv:param-add]: Resolve value of @value before
    processing numeric expression (to support template variables).  Error
    when any values are not numeric rather than producing NaN.
---
 src/current/include/preproc/template.xsl | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/current/include/preproc/template.xsl b/src/current/include/preproc/template.xsl
index c85d2865..d7216ff7 100644
--- a/src/current/include/preproc/template.xsl
+++ b/src/current/include/preproc/template.xsl
@@ -845,13 +845,31 @@
 <xsl:template mode="preproc:gen-param-value" priority="5"
               match="lv:param-add">
   <!-- calculate the param value -->
-  <xsl:variable name="param-value">
+  <xsl:variable name="name-value">
     <xsl:call-template name="preproc:template-param-value">
       <xsl:with-param name="name" select="@name" />
     </xsl:call-template>
   </xsl:variable>
 
-  <xsl:value-of select="number($param-value) + number(@value)" />
+  <xsl:variable name="value-value">
+    <xsl:call-template name="preproc:template-param-value">
+      <xsl:with-param name="name" select="@value" />
+    </xsl:call-template>
+  </xsl:variable>
+
+  <xsl:if test="not( $name-value castable as xs:float )">
+    <xsl:message terminate="yes"
+                 select="concat( 'error: non-numeric lv:param-add/@name: ',
+                                 $name-value )" />
+  </xsl:if>
+
+  <xsl:if test="not( $value-value castable as xs:float )">
+    <xsl:message terminate="yes"
+                 select="concat( 'error: non-numeric lv:param-add/@value: ',
+                                 $name-value )" />
+  </xsl:if>
+
+  <xsl:value-of select="number( $name-value ) + number( $value-value )" />
 </xsl:template>