Real test linking real other entry

src/test/java/org/jabref/model/entry/EntryLinkListTest.java

@@ -1,6 +1,7 @@
 package org.jabref.model.entry;
 
 import org.jabref.model.database.BibDatabase;
+import org.junit.Before;
 import org.junit.Test;
 
 import java.util.List;
@@ -11,10 +12,29 @@
 
 public class EntryLinkListTest {
 
-    private String key = "test";
-    private BibDatabase database = new BibDatabase();
-    private List<ParsedEntryLink> links = EntryLinkList.parse(key, database);
-    private ParsedEntryLink link = links.get(0);
+    private static final String key = "test";
+
+    private BibDatabase database;
+    private List<ParsedEntryLink> links;
+    private ParsedEntryLink link;
+    private BibEntry source;
+    private BibEntry target;
+
+    @Before
+    public void before() {
+        database = new BibDatabase();
+        links = EntryLinkList.parse(key, database);
+        link = links.get(0);
+        source = create("source");
+        target = create("target");
+    }
+
+    private BibEntry create(String citeKey) {
+        BibEntry entry = new BibEntry();
+        entry.setCiteKey(citeKey);
+        database.insertEntry(entry);
+        return entry;
+    }
 
     @Test
     public void givenFieldValueAndDatabaseWhenParsingThenExpectKey() {
@@ -42,4 +62,16 @@ public void givenNullFieldValueAndDatabaseWhenParsingThenExpectLinksIsEmpty() {
         links = EntryLinkList.parse(null, database);
         assertTrue(links.isEmpty());
     }
+
+    @Test
+    public void givenTargetAndSourceWhenSourceCrossrefTargetThenSourceCrossrefsTarget() {
+        source.setField(FieldName.CROSSREF, "target");
+        assertSourceCrossrefsTarget(target, source);
+    }
+
+    private void assertSourceCrossrefsTarget(BibEntry target, BibEntry source) {
+        Optional<String> sourceCrossref = source.getField(FieldName.CROSSREF);
+        Optional<String> targetCiteKey = target.getCiteKeyOptional();
+        assertEquals(sourceCrossref, targetCiteKey);
+    }
 }