added test for issue #4

commit 9f88e28 seems to fix #4 - this commit provides a regression test for it

xprocspec/src/it/it-xprocspec/src/test/xprocspec/steps/temp-dir-option.xpl

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<p:declare-step name="main" xmlns:p="http://www.w3.org/ns/xproc" xmlns:c="http://www.w3.org/ns/xproc-step" xmlns:ex="http://example.net/ns" type="ex:temp-dir-option" version="1.0">
+
+    <p:output port="result" primary="true"/>
+
+    <p:option name="temp-dir" select="'default temp-dir value'"/>
+    <p:option name="output-dir" select="'default output-dir value'"/>
+
+    <p:add-attribute match="/*" attribute-name="temp-dir">
+        <p:input port="source">
+            <p:inline exclude-inline-prefixes="#all">
+                <c:result/>
+            </p:inline>
+        </p:input>
+        <p:with-option name="attribute-value" select="$temp-dir"/>
+    </p:add-attribute>
+
+    <p:add-attribute match="/*" attribute-name="output-dir">
+        <p:with-option name="attribute-value" select="$output-dir"/>
+    </p:add-attribute>
+
+</p:declare-step>

xprocspec/src/it/it-xprocspec/src/test/xprocspec/tests/regression-tests/issue-4_temp-dir-option.xprocspec

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<?xml-model href="http://www.daisy.org/ns/xprocspec/xprocspec.rng" type="application/xml" schematypens="http://relaxng.org/ns/structure/1.0"?>
+<x:description xmlns:x="http://www.daisy.org/ns/xprocspec" xmlns:ex="http://example.net/ns" script="../../steps/temp-dir-option.xpl">
+
+    <x:scenario label="temp-dir">
+        <x:call step="ex:temp-dir-option">
+            <x:option name="temp-dir" select="'xprocspec temp-dir value'"/>
+            <x:option name="output-dir" select="'xprocspec output-dir value'"/>
+        </x:call>
+        <x:context label="the result">
+            <x:document type="port" port="result"/>
+        </x:context>
+        <x:expect type="count" label="there should be one document on the result port" min="1" max="1"/>
+        <x:expect type="xpath" label="the value of the temp-dir attribute should be 'xprocspec temp-dir value'" test="/*/@temp-dir" equals="'xprocspec temp-dir value'"/>
+        <x:expect type="xpath" label="the value of the output-dir attribute should be 'xprocspec output-dir value'" test="/*/@output-dir" equals="'xprocspec output-dir value'"/>
+    </x:scenario>
+
+</x:description>