Revamped external function result trees

* the root node of the result tree of each function is a domain element
** i.e. the root node of "read-xml-file" is "file", the root node of "read-directory" is "directory"
* the root node contains the result state of the function call encoded in a "result" attribute
** possible values are "success" and "error"
** the root node may contain additional attributes such as the target path of a called transformation
* the actual function result is contained within the child nodes of the function root node
** i.e. the XML file tree returned by "read-xml-file" is a child of the function root node
** if specific errors occured they are also returned as child nodes of the function root node
*** this is currently only the case for "transform" where transformation errors are returned as "error" value node childs of the function root node
* updated test cases accordingly

5 files changed, 70 insertions, 23 deletions

diff --git a/test/external_text_formatter/transformation.xsl b/test/external_text_formatter/transformation.xsl
index 00fe3b3..a94f211 100644
--- a/test/external_text_formatter/transformation.xsl
+++ b/test/external_text_formatter/transformation.xsl
@@ -20,13 +20,24 @@
 		)
 	</xsl:variable>
 
-	<xsl:copy-of select="dyn:evaluate($command)/output/*"/>
+	<xsl:copy-of select="dyn:evaluate($command)"/>
 </xsl:template>
 
 <xsl:template name="implementation">
-	<xsl:call-template name="formatter">
-		<xsl:with-param name="source" select="InputXSLT:read-file('test.md')"/>
-	</xsl:call-template>
+	<xsl:variable name="result">
+		<xsl:call-template name="formatter">
+			<xsl:with-param name="source" select="InputXSLT:read-file('test.md')"/>
+		</xsl:call-template>
+	</xsl:variable>
+
+	<xsl:choose>
+		<xsl:when test="xalan:nodeset($result)/output/@result = 'success'">
+			<xsl:copy-of select="xalan:nodeset($result)/output/*"/>
+		</xsl:when>
+		<xsl:otherwise>
+			Failure during external text formatting
+		</xsl:otherwise>
+	</xsl:choose>
 </xsl:template>
 
 </xsl:stylesheet>
diff --git a/test/read_directory/transformation.xsl b/test/read_directory/transformation.xsl
index 9a9a057..f1446a2 100644
--- a/test/read_directory/transformation.xsl
+++ b/test/read_directory/transformation.xsl
@@ -2,22 +2,34 @@
 <xsl:stylesheet
 	version="1.0"
 	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:xalan="http://xml.apache.org/xalan"
 	xmlns:InputXSLT="function.inputxslt.application"
-	exclude-result-prefixes="InputXSLT"
+	exclude-result-prefixes="InputXSLT xalan"
 >
 
 <xsl:include href="[testcase.xsl]"/>
 
 <xsl:template name="implementation">
-	<xsl:for-each select="InputXSLT:read-directory('../')">
-		<item type="{@type}">
-			<name><xsl:value-of select="./name"/></name>
+	<xsl:variable name="result">
+		<xsl:copy-of select="InputXSLT:read-directory('../')"/>
+	</xsl:variable>
 
-			<xsl:if test="@type='file' and ./name='check'">
-				<extension><xsl:value-of select="./extension"/></extension>
-			</xsl:if>
-		</item>
-	</xsl:for-each>
+	<xsl:choose>
+		<xsl:when test="xalan:nodeset($result)/directory/@result = 'success'">
+			<xsl:for-each select="xalan:nodeset($result)/directory/entry">
+				<item type="{@type}">
+					<name><xsl:value-of select="./name"/></name>
+
+					<xsl:if test="@type='file' and ./name='check'">
+						<extension><xsl:value-of select="./extension"/></extension>
+					</xsl:if>
+				</item>
+			</xsl:for-each>
+		</xsl:when>
+		<xsl:otherwise>
+			Error during directory io
+		</xsl:otherwise>
+	</xsl:choose>
 </xsl:template>
 
 </xsl:stylesheet>
diff --git a/test/read_file/transformation.xsl b/test/read_file/transformation.xsl
index f773e0e..9610046 100644
--- a/test/read_file/transformation.xsl
+++ b/test/read_file/transformation.xsl
@@ -2,14 +2,26 @@
 <xsl:stylesheet
 	version="1.0"
 	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:xalan="http://xml.apache.org/xalan"
 	xmlns:InputXSLT="function.inputxslt.application"
-	exclude-result-prefixes="InputXSLT"
+	exclude-result-prefixes="InputXSLT xalan"
 >
 
 <xsl:include href="[testcase.xsl]"/>
 
 <xsl:template name="implementation">
-	<xsl:value-of select="InputXSLT:read-file('test.txt')"/>
+	<xsl:variable name="result">
+		<xsl:copy-of select="InputXSLT:read-file('test.txt')"/>
+	</xsl:variable>
+
+	<xsl:choose>
+		<xsl:when test="xalan:nodeset($result)/file/@result = 'success'">
+			<xsl:value-of select="xalan:nodeset($result)/file"/>
+		</xsl:when>
+		<xsl:otherwise>
+			Error during file io
+		</xsl:otherwise>
+	</xsl:choose>
 </xsl:template>
 
 </xsl:stylesheet>
diff --git a/test/read_xml_file/transformation.xsl b/test/read_xml_file/transformation.xsl
index 2a6c5e5..f23273e 100644
--- a/test/read_xml_file/transformation.xsl
+++ b/test/read_xml_file/transformation.xsl
@@ -2,16 +2,28 @@
 <xsl:stylesheet
 	version="1.0"
 	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:xalan="http://xml.apache.org/xalan"
 	xmlns:InputXSLT="function.inputxslt.application"
-	exclude-result-prefixes="InputXSLT"
+	exclude-result-prefixes="InputXSLT xalan"
 >
 
 <xsl:include href="[testcase.xsl]"/>
 
 <xsl:template name="implementation">
-	<xsl:for-each select="InputXSLT:read-xml-file('test.txt')/tester/eintrag">
-		<item><xsl:value-of select="."/></item>
-	</xsl:for-each>
+	<xsl:variable name="result">
+		<xsl:copy-of select="InputXSLT:read-xml-file('test.txt')"/>
+	</xsl:variable>
+
+	<xsl:choose>
+		<xsl:when test="xalan:nodeset($result)/file/@result = 'success'">
+			<xsl:for-each select="xalan:nodeset($result)/file/tester/eintrag">
+				<item><xsl:value-of select="."/></item>
+			</xsl:for-each>
+		</xsl:when>
+		<xsl:otherwise>
+			Error during file io
+		</xsl:otherwise>
+	</xsl:choose>
 </xsl:template>
 
 </xsl:stylesheet>
diff --git a/test/transform/transformation.xsl b/test/transform/transformation.xsl
index 19c42ae..412036b 100644
--- a/test/transform/transformation.xsl
+++ b/test/transform/transformation.xsl
@@ -38,13 +38,13 @@
 	</xsl:variable>
 
 	<xsl:choose>
-		<xsl:when test="xalan:nodeset($result)/result/error">
-			<xsl:copy-of select="xalan:nodeset($result)/result/error"/>
-		</xsl:when>
-		<xsl:otherwise>
+		<xsl:when test="xalan:nodeset($result)/transformation/@result = 'success'">
 			<xsl:copy-of select="
 				InputXSLT:read-xml-file('test_actual.xml')/test_case/transform_test/*
 			"/>
+		</xsl:when>
+		<xsl:otherwise>
+			<xsl:copy-of select="xalan:nodeset($result)/transformation/*"/>
 		</xsl:otherwise>
 	</xsl:choose>
 </xsl:template>