Resolve #187: Make delimiter in concat optional

Makes the `delimiter` attribute in the `concat` collector optional. If
no delimiter is set then an empty string is used.

Author: cboehme

src/main/resources/schemata/metamorph.xsd

@@ -217,7 +217,7 @@
 	<element name="all">
 		<annotation>
 			<documentation>Outputs an unnamed literal with "true" as value if all
-			contained statements fire. This is essentially a conjunction (logical 
+			contained statements fire. This is essentially a conjunction (logical
 			and-operation) of all contained statements. The name and value generated
 			by the all-statement can be customised.</documentation>
 		</annotation>
@@ -236,7 +236,7 @@
 	<element name="any">
 		<annotation>
 			<documentation>Outputs an unnamed literal with "true" as value if any of
-			the contained statements fires. This is essentially a disjunction (logical 
+			the contained statements fires. This is essentially a disjunction (logical
 			or-operation) of all contained statements. The name and value generated
 			by the all-statement can be customised.</documentation>
 		</annotation>
@@ -264,7 +264,7 @@
 			</sequence>
 			<attribute name="name" type="string" use="optional" />
 			<attribute name="value" type="string" use="optional" />
-			<attribute name="flushWith" type="string" use="optional" 
+			<attribute name="flushWith" type="string" use="optional"
 				default="record" />
 			<attribute name="reset" type="boolean" use="optional"
 				default="false" />
@@ -288,7 +288,7 @@
 			<attribute name="flushWith" type="string" use="optional" />
 		</complexType>
 	</element>
-	
+
 	<element name="equalsFilter">
 		<complexType>
 			<sequence>
@@ -313,12 +313,12 @@
 		</annotation>
 		<complexType>
 			<sequence>
-				<element ref="tns:if" minOccurs="0" maxOccurs="1" />			
+				<element ref="tns:if" minOccurs="0" maxOccurs="1" />
 				<group ref="tns:literal-rule" minOccurs="1" maxOccurs="unbounded" />
 				<element ref="tns:postprocess" minOccurs="0" maxOccurs="1" />
 			</sequence>
 			<attribute name="name" type="string" use="required" />
-			<attribute name="delimiter" type="string" use="required" />
+			<attribute name="delimiter" type="string" use="optional" default="" />
 			<attribute name="prefix" type="string" use="optional" />
 			<attribute name="postfix" type="string" use="optional" />
 			<attribute name="reverse" type="boolean" use="optional" default="false">
@@ -506,7 +506,7 @@
 			</sequence>
 		</complexType>
 	</element>
-	
+
 	<element name="postprocess">
 		<annotation>
 			<documentation>The functions contained here are applied to the final
@@ -691,7 +691,7 @@
 	<!-- <complexType> -->
 	<!-- <attribute name="name" type="string" use="required" /> -->
 	<!-- <attribute name="value" type="string" use="required" /> -->
-	<!-- <attribute name="in" type="string" use="optional" default="record" 
+	<!-- <attribute name="in" type="string" use="optional" default="record"
 		/> -->
 	<!-- </complexType> -->
 	<!-- </element> -->

src/test/java/org/culturegraph/mf/morph/collectors/ConcatTest.xml

@@ -190,4 +190,25 @@
 		</result>
 	</test-case>
 
+	<test-case name="issue187_shouldUseEmptyDelimiterAsDefault">
+		<input type="text/x-formeta">
+			{
+				lit: data1,
+				lit: data2
+			}
+		</input>
+		<transformation type="text/x-metamorph+xml">
+			<mm:metamorph version="1">
+				<mm:rules>
+					<mm:concat name="concat">
+						<mm:data source="lit" />
+					</mm:concat>
+				</mm:rules>
+			</mm:metamorph>
+		</transformation>
+		<result type="text/x-formeta">
+			{ concat: data1data2 }
+		</result>
+	</test-case>
+
 </metamorph-test>