Add a basic test of the dependency graph serialization for ProtobufAn…

…notationSerializer

test/src/edu/stanford/nlp/pipeline/ProtobufAnnotationSerializerTest.java

@@ -0,0 +1,48 @@
+package edu.stanford.nlp.pipeline;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import edu.stanford.nlp.ling.CoreLabel;
+import edu.stanford.nlp.ling.IndexedWord;
+import edu.stanford.nlp.semgraph.SemanticGraph;
+
+/**
+ * A test of a few specific methods in the ProtobufAnnotationSerializer
+ *
+ * @author John Bauer
+ */
+public class ProtobufAnnotationSerializerTest {
+  /** Test serializing a graph and deserializing it */
+  @Test
+  public void testDependencySerialization() {
+    checkGraphReversible("[A/foo-3 obj> B/bar-1 obj> C-4 nsubj> [D-2 obj> E-0]]");
+  }
+
+  /** Test that it still works if one of the nodes has an emptyIndex */
+  @Test
+  public void testDependencySerializationWithEmpty() {
+    checkGraphReversible("[A/foo-3 obj> B/bar-1 obj> C-4 nsubj> [D-1.1 obj> E-0]]");
+  }
+
+  private void checkGraphReversible(String rawGraph) {
+    ProtobufAnnotationSerializer serializer = new ProtobufAnnotationSerializer();
+
+    // test some with tags and some without
+    SemanticGraph sg = SemanticGraph.valueOf(rawGraph);
+
+    CoreNLPProtos.DependencyGraph graphProto = serializer.toProto(sg, true);
+    List<CoreLabel> labels = new ArrayList<>();
+    for (CoreNLPProtos.Token tokenProto : graphProto.getTokenList()) {
+      CoreLabel nextToken = serializer.fromProto(tokenProto);
+      labels.add(nextToken);
+    }
+
+    SemanticGraph unpacked = serializer.fromProto(graphProto, labels, null);
+    Assert.assertEquals(sg, unpacked);
+  }
+
+}