fixed Matcher.hasXpath against multiple element

hamcrest/src/main/java/org/hamcrest/xml/HasXPath.java

@@ -6,14 +6,18 @@
 import org.hamcrest.TypeSafeDiagnosingMatcher;
 import org.hamcrest.core.IsAnything;
 import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
 
 import javax.xml.namespace.NamespaceContext;
 import javax.xml.namespace.QName;
 import javax.xml.xpath.*;
 
+import java.util.ArrayList;
+import java.util.List;
+
+import static javax.xml.xpath.XPathConstants.NODESET;
 import static javax.xml.xpath.XPathConstants.STRING;
-import static org.hamcrest.Condition.matched;
-import static org.hamcrest.Condition.notMatched;
+import static org.hamcrest.Condition.*;
 
 /**
  * Applies a Matcher to a given XML Node in an existing XML Node tree, specified by an XPath expression.
@@ -58,9 +62,22 @@ private HasXPath(String xPathExpression, NamespaceContext namespaceContext, Matc
 
     @Override
     public boolean matchesSafely(Node item, Description mismatch) {
-        return evaluated(item, mismatch)
-               .and(NODE_EXISTS)
-               .matching(valueMatcher);
+        if (this.evaluationMode == NODESET)
+        {
+            List<Condition<Object>> match_list = evaluatedList(item, mismatch);
+
+            for (Condition<Object> match: match_list) {
+                if (match.and(NODE_EXISTS).matching(valueMatcher)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        else {
+            return evaluated(item, mismatch)
+                    .and(NODE_EXISTS)
+                    .matching(valueMatcher);
+        }
     }
 
     @Override
@@ -80,6 +97,22 @@ private Condition<Object> evaluated(Node item, Description mismatch) {
         return notMatched();
     }
 
+    private List<Condition<Object>> evaluatedList(Node item, Description mismatch) {
+        List<Condition<Object>> match_list = new ArrayList<>();
+        try {
+            NodeList list = (NodeList) compiledXPath.evaluate(item, evaluationMode);
+            for (int i = 0; i < list.getLength(); i++) {
+                Node node = list.item(i);
+                match_list.add((matched((Object)node.getTextContent(), mismatch)));
+            }
+            return match_list;
+        } catch (XPathExpressionException e) {
+            mismatch.appendText(e.getMessage());
+        }
+        match_list.add(notMatched());
+        return match_list;
+    }
+
     private static Condition.Step<Object, String> nodeExists() {
         return new Condition.Step<Object, String>() {
             @Override
@@ -136,7 +169,7 @@ public static Matcher<Node> hasXPath(String xPath, Matcher<String> valueMatcher)
      *     matcher for the value at the specified xpath
      */
     public static Matcher<Node> hasXPath(String xPath, NamespaceContext namespaceContext, Matcher<String> valueMatcher) {
-        return new HasXPath(xPath, namespaceContext, valueMatcher, STRING);
+        return new HasXPath(xPath, namespaceContext, valueMatcher, NODESET);
     }
 
     /**

hamcrest/src/test/java/org/hamcrest/xml/HasXPathTest.java

@@ -75,6 +75,41 @@ public Iterator<String> getPrefixes(String namespaceURI) {
         assertMatches(hasXPath("//something[@id='b']/cheese"), xml);
     }
 
+    /*
+    Test whether the multiple elements case works or not
+     */
+    @Test public void
+    appliesMatcherToXPathInDocumentWithMultipleElement() {
+        Document multipleBookXml = parse("<books>\n"
+                + "<book>\n"
+                + "<isbn>A-ISBN</isbn>\n"
+                + "</book>\n"
+                + "<book>\n"
+                + "<isbn>B-ISBN</isbn>\n"
+                + "<name>B-Book></name>\n"
+                + "</book>\n"
+                + "</books>\n"
+        );
+
+        assertMatches(hasXPath("/books/book/isbn", equalTo("B-ISBN")), multipleBookXml);
+        assertMatches(hasXPath("/books/book/isbn", equalTo("A-ISBN")), multipleBookXml);
+    }
+
+    /*
+    Test whether the single element case still works or not
+     */
+    @Test public void
+    appliesMatcherToPathInDocumentWithSingleElement() {
+        Document multipleBookXml = parse("<books>\n"
+                + "<book>\n"
+                + "<isbn>A-ISBN</isbn>\n"
+                + "</book>\n"
+                + "</books>\n"
+        );
+
+        assertMatches(hasXPath("/books/book/isbn", equalTo("A-ISBN")), multipleBookXml);
+    }
+
     @Test public void
     matchesEmptyElement() {
         assertMatches(hasXPath("//emptySomething"), xml);