Update Wikidata-Toolkit to solve various issues (#2215)

Updates Wikidata-Toolkit to 0.11.0

This enables the following improvements:
- https://github.com/Wikidata/Wikidata-Toolkit/issues/431
- https://github.com/Wikidata/Wikidata-Toolkit/issues/456

This closes #2196 although the feature will not be enabled until 3.4 for technical reasons
(the openrefine-3.3 tag on Wikidata can only be applied by an AbuseFilter, not manually through
the API).

* Update WDTK and add timeouts to Wikidata editing, closes #2211.

* Explicitly add wdtk-util as a dependency

* Catch MediaWikiApiError following change of interface

extensions/wikidata/pom.xml

@@ -128,12 +128,17 @@
     <dependency>
       <groupId>org.wikidata.wdtk</groupId>
       <artifactId>wdtk-wikibaseapi</artifactId>
-      <version>0.10.0</version>
+      <version>0.11.0</version>
     </dependency>
     <dependency>
       <groupId>org.wikidata.wdtk</groupId>
       <artifactId>wdtk-datamodel</artifactId>
-      <version>0.10.0</version>
+      <version>0.11.0</version>
+    </dependency>
+    <dependency>
+      <groupId>org.wikidata.wdtk</groupId>
+      <artifactId>wdtk-util</artifactId>
+      <version>0.11.0</version>
     </dependency>
     <dependency>
       <groupId>org.slf4j</groupId>

extensions/wikidata/src/org/openrefine/wikidata/editing/ConnectionManager.java

@@ -28,7 +28,9 @@ import java.io.IOException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.wikidata.wdtk.wikibaseapi.ApiConnection;
+import org.wikidata.wdtk.wikibaseapi.BasicApiConnection;
 import org.wikidata.wdtk.wikibaseapi.LoginFailedException;
+import org.wikidata.wdtk.wikibaseapi.apierrors.MediaWikiApiErrorException;
 
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
@@ -54,9 +56,11 @@ public class ConnectionManager {
     final static Logger logger = LoggerFactory.getLogger("connection_mananger");
 
     public static final String PREFERENCE_STORE_KEY = "wikidata_credentials";
+    public static final int CONNECT_TIMEOUT = 5000;
+    public static final int READ_TIMEOUT = 10000;
 
     private PreferenceStore prefStore;
-    private ApiConnection connection;
+    private BasicApiConnection connection;
 
     private static final ConnectionManager instance = new ConnectionManager();
 
@@ -64,12 +68,26 @@ public class ConnectionManager {
         return instance;
     }
 
+    /**
+     * Creates a connection manager, which attempts to restore any
+     * previous connection (from the preferences).
+     */
     private ConnectionManager() {
         prefStore = ProjectManager.singleton.getPreferenceStore();
         connection = null;
         restoreSavedConnection();
     }
 
+    /**
+     * Logs in to the Wikibase instance, using login/password
+     * 
+     * @param username
+     *      the username to log in with
+     * @param password
+     *      the password to log in with
+     * @param rememberCredentials
+     *      whether to store these credentials in the preferences (unencrypted!)
+     */
     public void login(String username, String password, boolean rememberCredentials) {
         if (rememberCredentials) {
             ArrayNode array = ParsingUtilities.mapper.createArrayNode();
@@ -80,7 +98,7 @@ public class ConnectionManager {
             prefStore.put(PREFERENCE_STORE_KEY, array);
         }
 
-        connection = ApiConnection.getWikidataApiConnection();
+        connection = createNewConnection();
         try {
             connection.login(username, password);
         } catch (LoginFailedException e) {
@@ -88,10 +106,13 @@ public class ConnectionManager {
         }
     }
 
+    /**
+     * Restore any previously saved connection, from the preferences.
+     */
     public void restoreSavedConnection() {
         ObjectNode savedCredentials = getStoredCredentials();
         if (savedCredentials != null) {
-            connection = ApiConnection.getWikidataApiConnection();
+            connection = createNewConnection();
             try {
                 connection.login(savedCredentials.get("username").asText(), savedCredentials.get("password").asText());
             } catch (LoginFailedException e) {
@@ -114,7 +135,7 @@ public class ConnectionManager {
             try {
                 connection.logout();
                 connection = null;
-            } catch (IOException e) {
+            } catch (IOException | MediaWikiApiErrorException e) {
                 logger.error(e.getMessage());
             }
         }
@@ -135,4 +156,16 @@ public class ConnectionManager {
             return null;
         }
     }
+    
+    /**
+     * Creates a fresh connection object with our
+     * prefered settings.
+     * @return
+     */
+    protected BasicApiConnection createNewConnection() {
+        BasicApiConnection conn = BasicApiConnection.getWikidataApiConnection();
+        conn.setConnectTimeout(CONNECT_TIMEOUT);
+        conn.setReadTimeout(READ_TIMEOUT);
+        return conn;
+    }
 }

extensions/wikidata/src/org/openrefine/wikidata/editing/EditBatchProcessor.java

@@ -59,6 +59,7 @@ public class EditBatchProcessor {
     private NewItemLibrary library;
     private List<ItemUpdate> scheduled;
     private String summary;
+    private List<String> tags;
 
     private List<ItemUpdate> remainingUpdates;
     private List<ItemUpdate> currentBatch;
@@ -82,12 +83,14 @@ public class EditBatchProcessor {
      *            the library to use to keep track of new item creation
      * @param summary
      *            the summary to append to all edits
+     * @param tags
+     *            the list of tags to apply to all edits
      * @param batchSize
      *            the number of items that should be retrieved in one go from the
      *            API
      */
     public EditBatchProcessor(WikibaseDataFetcher fetcher, WikibaseDataEditor editor, List<ItemUpdate> updates,
-            NewItemLibrary library, String summary, int batchSize) {
+            NewItemLibrary library, String summary, List<String> tags, int batchSize) {
         this.fetcher = fetcher;
         this.editor = editor;
         editor.setEditAsBot(true); // this will not do anything if the user does not
@@ -99,6 +102,7 @@ public class EditBatchProcessor {
 
         this.library = library;
         this.summary = summary;
+        this.tags = tags;
         this.batchSize = batchSize;
 
         // Schedule the edit batch
@@ -133,6 +137,7 @@ public class EditBatchProcessor {
         	update = rewriter.rewrite(update);
         } catch (NewItemNotCreatedYetException e) {
         	logger.warn("Failed to rewrite update on entity "+update.getItemId()+". Missing entity: "+e.getMissingEntity()+". Skipping update.");
+        	batchCursor++;
         	return;
         }
 
@@ -148,8 +153,8 @@ public class EditBatchProcessor {
                         update.getAliases().stream().collect(Collectors.toList()), update.getAddedStatementGroups(),
                         Collections.emptyMap());
 
-                ItemDocument createdDoc = editor.createItemDocument(itemDocument, summary);
+                ItemDocument createdDoc = editor.createItemDocument(itemDocument, summary, tags);
-                library.setQid(newCell.getReconInternalId(), createdDoc.getItemId().getId());
+                library.setQid(newCell.getReconInternalId(), createdDoc.getEntityId().getId());
             } else {
                 // Existing item
                 ItemDocument currentDocument = (ItemDocument) currentDocs.get(update.getItemId().getId());
@@ -165,7 +170,8 @@ public class EditBatchProcessor {
                         update.getAliases().stream().collect(Collectors.toList()),
                         new ArrayList<MonolingualTextValue>(),
                         update.getAddedStatements().stream().collect(Collectors.toList()),
-                        update.getDeletedStatements().stream().collect(Collectors.toList()), summary);
+                        update.getDeletedStatements().stream().collect(Collectors.toList()),
+                        summary, tags);
             }
         } catch (MediaWikiApiErrorException e) {
             // TODO find a way to report these errors to the user in a nice way

extensions/wikidata/src/org/openrefine/wikidata/exporters/QSValuePrinter.java

@@ -28,7 +28,6 @@ import java.util.Locale;
 
 import org.openrefine.wikidata.schema.entityvalues.ReconEntityIdValue;
 import org.openrefine.wikidata.updates.scheduler.QuickStatementsUpdateScheduler;
-import org.wikidata.wdtk.datamodel.interfaces.DatatypeIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.GlobeCoordinatesValue;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
@@ -36,6 +35,7 @@ import org.wikidata.wdtk.datamodel.interfaces.MonolingualTextValue;
 import org.wikidata.wdtk.datamodel.interfaces.QuantityValue;
 import org.wikidata.wdtk.datamodel.interfaces.StringValue;
 import org.wikidata.wdtk.datamodel.interfaces.TimeValue;
+import org.wikidata.wdtk.datamodel.interfaces.UnsupportedValue;
 import org.wikidata.wdtk.datamodel.interfaces.ValueVisitor;
 
 /**
@@ -96,4 +96,10 @@ public class QSValuePrinter implements ValueVisitor<String> {
         return String.format("+%04d-%02d-%02dT%02d:%02d:%02dZ/%d", value.getYear(), value.getMonth(), value.getDay(),
                 value.getHour(), value.getMinute(), value.getSecond(), value.getPrecision());
     }
+
+    @Override
+    public String visit(UnsupportedValue value) {
+            // we know this cannot happen, since UnsupportedValues cannot be generated in OpenRefine
+            return "<UNSUPPORTED>";
+    }
 }

extensions/wikidata/src/org/openrefine/wikidata/operations/PerformWikibaseEditsOperation.java

@@ -26,11 +26,16 @@ package org.openrefine.wikidata.operations;
 import java.io.IOException;
 import java.io.LineNumberReader;
 import java.io.Writer;
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Properties;
 import java.util.Random;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.apache.commons.lang.Validate;
+import org.apache.log4j.spi.LoggerRepository;
 import org.openrefine.wikidata.editing.ConnectionManager;
 import org.openrefine.wikidata.editing.EditBatchProcessor;
 import org.openrefine.wikidata.editing.NewItemLibrary;
@@ -46,6 +51,7 @@ import org.wikidata.wdtk.wikibaseapi.WikibaseDataFetcher;
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.refine.RefineServlet;
 import com.google.refine.browsing.Engine;
 import com.google.refine.browsing.EngineConfig;
 import com.google.refine.history.Change;
@@ -143,6 +149,7 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
         protected Engine _engine;
         protected WikibaseSchema _schema;
         protected String _summary;
+        protected List<String> _tags;
         protected final long _historyEntryID;
 
         protected PerformEditsProcess(Project project, Engine engine, String description, String summary) {
@@ -151,6 +158,15 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
             this._engine = engine;
             this._schema = (WikibaseSchema) project.overlayModels.get("wikibaseSchema");
             this._summary = summary;
+            // TODO this is one of the attributes that should be configured on a per-wiki basis
+            // TODO enable this tag once 3.3 final is released and create 3.4 tag without AbuseFilter
+            String tag = "openrefine";
+            Pattern pattern = Pattern.compile("^(\\d+\\.\\d+).*$");
+            Matcher matcher = pattern.matcher(RefineServlet.VERSION);
+            if (matcher.matches()) {
+                tag += "-"+matcher.group(1);
+            }
+            this._tags = Collections.emptyList(); // TODO Arrays.asList(tag);
             this._historyEntryID = HistoryEntry.allocateID();
         }
 
@@ -183,7 +199,7 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
             // Prepare the edits
             NewItemLibrary newItemLibrary = new NewItemLibrary();
             EditBatchProcessor processor = new EditBatchProcessor(wbdf, wbde, itemDocuments, newItemLibrary, summary,
-                    50);
+                    _tags, 50);
 
             // Perform edits
             logger.info("Performing edits");

extensions/wikidata/src/org/openrefine/wikidata/qa/scrutinizers/QuantityScrutinizer.java

@@ -1,10 +1,8 @@
 package org.openrefine.wikidata.qa.scrutinizers;
 
 import java.util.Set;
-import java.util.stream.Collectors;
 
 import org.openrefine.wikidata.qa.QAWarning;
-import org.wikidata.wdtk.datamodel.helpers.Datamodel;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.PropertyIdValue;

extensions/wikidata/src/org/openrefine/wikidata/schema/WbStatementGroupExpr.java

@@ -28,7 +28,6 @@ import java.util.List;
 
 import org.jsoup.helper.Validate;
 import org.openrefine.wikidata.schema.exceptions.SkipSchemaExpressionException;
-import org.openrefine.wikidata.utils.StatementGroupJson;
 import org.wikidata.wdtk.datamodel.helpers.Datamodel;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.PropertyIdValue;

extensions/wikidata/src/org/openrefine/wikidata/updates/ItemUpdate.java

@@ -32,12 +32,10 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.function.Function;
 import java.util.stream.Collectors;
 
 import org.jsoup.helper.Validate;
 import org.openrefine.wikidata.utils.StatementGroupJson;
-import org.wikidata.wdtk.datamodel.helpers.Datamodel;
 import org.wikidata.wdtk.datamodel.implementation.StatementGroupImpl;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;

extensions/wikidata/src/org/openrefine/wikidata/updates/scheduler/PointerExtractor.java

@@ -29,7 +29,6 @@ import java.util.List;
 import java.util.Set;
 
 import org.openrefine.wikidata.schema.entityvalues.ReconItemIdValue;
-import org.wikidata.wdtk.datamodel.interfaces.DatatypeIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.GlobeCoordinatesValue;
 import org.wikidata.wdtk.datamodel.interfaces.MonolingualTextValue;
@@ -39,6 +38,7 @@ import org.wikidata.wdtk.datamodel.interfaces.SnakGroup;
 import org.wikidata.wdtk.datamodel.interfaces.Statement;
 import org.wikidata.wdtk.datamodel.interfaces.StringValue;
 import org.wikidata.wdtk.datamodel.interfaces.TimeValue;
+import org.wikidata.wdtk.datamodel.interfaces.UnsupportedValue;
 import org.wikidata.wdtk.datamodel.interfaces.Value;
 import org.wikidata.wdtk.datamodel.interfaces.ValueVisitor;
 
@@ -158,4 +158,9 @@ public class PointerExtractor implements ValueVisitor<Set<ReconItemIdValue>> {
     public Set<ReconItemIdValue> visit(TimeValue value) {
         return null;
     }
+
+    @Override
+    public Set<ReconItemIdValue> visit(UnsupportedValue value) {
+        return null;
+    }
 }

extensions/wikidata/src/org/openrefine/wikidata/utils/EntityCache.java

@@ -29,6 +29,7 @@ import org.wikidata.wdtk.datamodel.helpers.Datamodel;
 import org.wikidata.wdtk.datamodel.interfaces.EntityDocument;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.wikibaseapi.ApiConnection;
+import org.wikidata.wdtk.wikibaseapi.BasicApiConnection;
 import org.wikidata.wdtk.wikibaseapi.WikibaseDataFetcher;
 import org.wikidata.wdtk.wikibaseapi.apierrors.MediaWikiApiErrorException;
 
@@ -44,7 +45,7 @@ public class EntityCache {
     private WikibaseDataFetcher _fetcher;
 
     private EntityCache() {
-        ApiConnection connection = ApiConnection.getWikidataApiConnection();
+        ApiConnection connection = BasicApiConnection.getWikidataApiConnection();
         _fetcher = new WikibaseDataFetcher(connection, Datamodel.SITE_WIKIDATA);
 
         _cache = CacheBuilder.newBuilder().maximumSize(4096).expireAfterWrite(1, TimeUnit.HOURS)

extensions/wikidata/src/org/openrefine/wikidata/utils/StatementGroupJson.java

@@ -2,7 +2,6 @@ package org.openrefine.wikidata.utils;
 
 import java.util.List;
 
-import org.wikidata.wdtk.datamodel.helpers.Datamodel;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.PropertyIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.Statement;

extensions/wikidata/tests/src/org/openrefine/wikidata/commands/LoginCommandTest.java

@@ -1,7 +1,7 @@
 package org.openrefine.wikidata.commands;
 
-import static org.testng.Assert.assertEquals;
 import static org.mockito.Mockito.when;
+import static org.testng.Assert.assertEquals;
 
 import java.io.IOException;
 

extensions/wikidata/tests/src/org/openrefine/wikidata/commands/PreviewWikibaseSchemaCommandTest.java

@@ -23,9 +23,9 @@
  ******************************************************************************/
 package org.openrefine.wikidata.commands;
 
-import static org.testng.Assert.assertEquals;
 import static org.mockito.Mockito.when;
 import static org.openrefine.wikidata.testing.TestingData.jsonFromFile;
+import static org.testng.Assert.assertEquals;
 
 import java.io.IOException;
 

extensions/wikidata/tests/src/org/openrefine/wikidata/commands/SaveWikibaseSchemaCommandTest.java

@@ -23,9 +23,9 @@
  ******************************************************************************/
 package org.openrefine.wikidata.commands;
 
-import static org.testng.Assert.assertTrue;
 import static org.mockito.Mockito.when;
 import static org.openrefine.wikidata.testing.TestingData.jsonFromFile;
+import static org.testng.Assert.assertTrue;
 
 import java.io.IOException;
 

extensions/wikidata/tests/src/org/openrefine/wikidata/commands/SchemaCommandTest.java

@@ -23,8 +23,8 @@
  ******************************************************************************/
 package org.openrefine.wikidata.commands;
 
-import static org.testng.Assert.assertEquals;
 import static org.mockito.Mockito.when;
+import static org.testng.Assert.assertEquals;
 
 import java.io.IOException;
 

extensions/wikidata/tests/src/org/openrefine/wikidata/editing/EditBatchProcessorTest.java

@@ -31,6 +31,7 @@ import static org.testng.Assert.assertEquals;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -58,6 +59,7 @@ public class EditBatchProcessorTest extends WikidataRefineTest {
     private WikibaseDataEditor editor = null;
     private NewItemLibrary library = null;
     private String summary = "my fantastic edits";
+    private List<String> tags = null;
 
     @BeforeMethod
     public void setUp() {
@@ -65,6 +67,7 @@ public class EditBatchProcessorTest extends WikidataRefineTest {
         editor = mock(WikibaseDataEditor.class);
         editor.disableEditing(); // just in case we got mocking wrong…
         library = new NewItemLibrary();
+        tags = Arrays.asList("my-tag");
     }
 
     @Test
@@ -87,9 +90,9 @@ public class EditBatchProcessorTest extends WikidataRefineTest {
         ItemDocument expectedNewItem = ItemDocumentBuilder.forItemId(TestingData.newIdA).withLabel(label).build();
         ItemDocument createdNewItem = ItemDocumentBuilder.forItemId(Datamodel.makeWikidataItemIdValue("Q1234"))
                 .withLabel(label).withRevisionId(37828L).build();
-        when(editor.createItemDocument(expectedNewItem, summary)).thenReturn(createdNewItem);
+        when(editor.createItemDocument(expectedNewItem, summary, tags)).thenReturn(createdNewItem);
 
-        EditBatchProcessor processor = new EditBatchProcessor(fetcher, editor, batch, library, summary, 50);
+        EditBatchProcessor processor = new EditBatchProcessor(fetcher, editor, batch, library, summary, tags, 50);
         assertEquals(2, processor.remainingEdits());
         assertEquals(0, processor.progress());
         processor.performEdit();
@@ -134,7 +137,7 @@ public class EditBatchProcessorTest extends WikidataRefineTest {
         when(fetcher.getEntityDocuments(toQids(secondBatch))).thenReturn(toMap(secondBatch));
 
         // Run edits
-        EditBatchProcessor processor = new EditBatchProcessor(fetcher, editor, batch, library, summary, batchSize);
+        EditBatchProcessor processor = new EditBatchProcessor(fetcher, editor, batch, library, summary, tags, batchSize);
         assertEquals(0, processor.progress());
         for (int i = 124; i < 190; i++) {
             assertEquals(processor.remainingEdits(), 190 - i);
@@ -150,15 +153,15 @@ public class EditBatchProcessorTest extends WikidataRefineTest {
         for (ItemDocument doc : fullBatch) {
             verify(editor, times(1)).updateTermsStatements(doc, Collections.emptyList(),
                     Collections.singletonList(description), Collections.emptyList(), Collections.emptyList(),
-                    Collections.emptyList(), Collections.emptyList(), summary);
+                    Collections.emptyList(), Collections.emptyList(), summary, tags);
         }
     }
 
     private Map<String, EntityDocument> toMap(List<ItemDocument> docs) {
-        return docs.stream().collect(Collectors.toMap(doc -> doc.getItemId().getId(), doc -> doc));
+        return docs.stream().collect(Collectors.toMap(doc -> doc.getEntityId().getId(), doc -> doc));
     }
 
     private List<String> toQids(List<ItemDocument> docs) {
-        return docs.stream().map(doc -> doc.getItemId().getId()).collect(Collectors.toList());
+        return docs.stream().map(doc -> doc.getEntityId().getId()).collect(Collectors.toList());
     }
 }

extensions/wikidata/tests/src/org/openrefine/wikidata/editing/NewItemLibraryTest.java

@@ -34,7 +34,6 @@ import org.openrefine.wikidata.testing.WikidataRefineTest;
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
-import com.google.refine.RefineTest;
 import com.google.refine.model.Cell;
 import com.google.refine.model.Project;
 import com.google.refine.model.Recon;

extensions/wikidata/tests/src/org/openrefine/wikidata/exporters/QuickStatementsExporterTest.java

@@ -45,7 +45,6 @@ import org.wikidata.wdtk.datamodel.interfaces.SnakGroup;
 import org.wikidata.wdtk.datamodel.interfaces.Statement;
 import org.wikidata.wdtk.datamodel.interfaces.StatementRank;
 
-import com.google.refine.RefineTest;
 import com.google.refine.browsing.Engine;
 import com.google.refine.model.Project;
 

extensions/wikidata/tests/src/org/openrefine/wikidata/exporters/SchemaExporterTest.java

@@ -7,7 +7,6 @@ import java.util.Properties;
 import org.openrefine.wikidata.testing.WikidataRefineTest;
 import org.testng.annotations.Test;
 
-import com.google.refine.RefineTest;
 import com.google.refine.browsing.Engine;
 import com.google.refine.model.Project;
 import com.google.refine.util.TestUtils;

extensions/wikidata/tests/src/org/openrefine/wikidata/updates/scheduler/PointerExtractorTest.java

@@ -23,6 +23,7 @@
  ******************************************************************************/
 package org.openrefine.wikidata.updates.scheduler;
 
+import static org.mockito.Mockito.mock;
 import static org.testng.Assert.assertEquals;
 
 import java.math.BigDecimal;
@@ -41,6 +42,7 @@ import org.wikidata.wdtk.datamodel.interfaces.Snak;
 import org.wikidata.wdtk.datamodel.interfaces.SnakGroup;
 import org.wikidata.wdtk.datamodel.interfaces.StatementRank;
 import org.wikidata.wdtk.datamodel.interfaces.TimeValue;
+import org.wikidata.wdtk.datamodel.interfaces.UnsupportedValue;
 import org.wikidata.wdtk.datamodel.interfaces.Value;
 
 public class PointerExtractorTest {
@@ -73,6 +75,7 @@ public class PointerExtractorTest {
         assertEmpty(Datamodel.makeQuantityValue(new BigDecimal("898")));
         assertEmpty(Datamodel.makeQuantityValue(new BigDecimal("7.87"), "http://www.wikidata.org/entity/Q34"));
         assertEmpty(Datamodel.makeTimeValue(1898, (byte) 2, (byte) 3, TimeValue.CM_GREGORIAN_PRO));
+        assertEmpty(mock(UnsupportedValue.class));
     }
 
     @Test