(tests): null check for vectors

src/test/java/io/anserini/index/IndexHnswDenseVectorsTest.java

@@ -19,13 +19,15 @@
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.util.Map;
+import io.anserini.index.generator.InvalidDocumentException;
 
 import org.apache.logging.log4j.Level;
 import org.apache.logging.log4j.core.config.Configurator;
 import org.apache.lucene.index.IndexReader;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
@@ -198,6 +200,43 @@ public void testParquetFloat() throws Exception {
     assertEquals(10, results.get("documents"));
   }
 
+  @Test
+  public void testNullVector() throws Exception {
+    // Test for JsonDenseVectorDocumentGenerator
+    String indexPath = "target/lucene-test-index.hnsw." + System.currentTimeMillis();
+    String[] indexArgs = new String[] {
+        "-collection", "JsonDenseVectorCollection",
+        "-input", "src/test/resources/sample_docs/openai_ada2/json_vector_null",
+        "-index", indexPath,
+        "-generator", "JsonDenseVectorDocumentGenerator",
+        "-threads", "1"
+    };
+
+    try {
+      IndexHnswDenseVectors.main(indexArgs);
+      fail("Expected InvalidDocumentException");
+    } catch (InvalidDocumentException e) {
+      // expected
+    }
+
+    // Test for JsonInvertedDenseVectorDocumentGenerator
+    indexPath = "target/lucene-test-index.hnsw." + System.currentTimeMillis();
+    indexArgs = new String[] {
+        "-collection", "JsonDenseVectorCollection",
+        "-input", "src/test/resources/sample_docs/openai_ada2/json_vector_null",
+        "-index", indexPath,
+        "-generator", "JsonInvertedDenseVectorDocumentGenerator",
+        "-threads", "1"
+    };
+
+    try {
+      IndexHnswDenseVectors.main(indexArgs);
+      fail("Expected InvalidDocumentException");
+    } catch (InvalidDocumentException e) {
+      // expected
+    }
+  }
+
   @Test
   public void testQuantizedInt8() throws Exception {
     String indexPath = "target/lucene-test-index.hnsw." + System.currentTimeMillis();

src/test/resources/sample_docs/openai_ada2/json_vector_null/sample.json

@@ -0,0 +1 @@
+{"docid": "1", "contents": "contents 1", "vector": null}