Fix false-positive in EnrichmentPipelineTest by introducing mock Config with DummyModule

src/test/java/com/digitalpebble/spruce/EnrichmentPipelineTest.java

@@ -4,13 +4,15 @@
 
 import org.apache.spark.sql.Row;
 import org.apache.spark.sql.catalyst.expressions.GenericRowWithSchema;
+import org.apache.spark.sql.types.DataTypes;
 import org.apache.spark.sql.types.StructType;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.CsvSource;
 
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 
 import static com.digitalpebble.spruce.CURColumn.*;
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -23,6 +25,56 @@
  */
 public class EnrichmentPipelineTest {
 
+    /** A lightweight test column used by DummyModule to verify enrichment. */
+    private static final Column DUMMY_ENRICHED = new Column("dummy_enriched", DataTypes.DoubleType) {};
+
+    /**
+     * Minimal {@link EnrichmentModule} for testing pipeline logic.
+     * Declares a single output column and sets it to a fixed value during process().
+     */
+    static class DummyModule implements EnrichmentModule {
+
+        @Override
+        public Column[] columnsNeeded() {
+            return new Column[0];
+        }
+
+        @Override
+        public Column[] columnsAdded() {
+            return new Column[]{ DUMMY_ENRICHED };
+        }
+
+        @Override
+        public Row process(Row row) {
+            return EnrichmentModule.withUpdatedValue(row, DUMMY_ENRICHED, 42.0);
+        }
+    }
+
+    /**
+     * Creates a Config pre-loaded with a single DummyModule.
+     * This avoids loading the real production modules (which require the full CUR schema)
+     * and keeps the test focused on the pipeline's Usage-filter logic.
+     */
+    private static Config createMockConfig() {
+        Config config = new Config();
+        DummyModule module = new DummyModule();
+        config.getModules().add(module);
+
+        // Also inject matching config entry via reflection so configureModules() works
+        try {
+            var configsField = Config.class.getDeclaredField("configs");
+            configsField.setAccessible(true);
+            @SuppressWarnings("unchecked")
+            List<Map<String, Object>> configs =
+                    (List<Map<String, Object>>) configsField.get(config);
+            configs.add(Collections.emptyMap());
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to set up mock config", e);
+        }
+
+        return config;
+    }
+
     /**
      * Verifies the selective enrichment logic based on Line Item Type.
      * <p>
@@ -39,21 +91,18 @@ public class EnrichmentPipelineTest {
             "Fee, false"
     })
     public void testPipelineEnrichmentLogic(String lineItemType, boolean expectEnrichment) throws Exception {
-        Config config = new Config();
+        Config config = createMockConfig();
         EnrichmentPipeline pipeline = new EnrichmentPipeline(config);
 
-        // TODO: Validate that modules are loaded (Option 1 - Mocking).
-        // Currently, new Config() returns an empty list in unit tests.
-        // We will implement a Mock Config in a separate PR to handle this without
-        // requiring the full production schema.
-        // assertFalse(config.getModules().isEmpty(), "Config should have at least one enrichment module");
+        List<EnrichmentModule> modules = config.getModules();
+        assertFalse(modules.isEmpty(), "Config should have at least one enrichment module for this test");
 
-        // Minimal schema: use ONLY existing constants in CURColumn.
+        // Minimal schema: base CUR columns + columns added by the DummyModule
         StructType schema = new StructType()
                 .add(PRODUCT_REGION_CODE.getLabel(), PRODUCT_REGION_CODE.getType(), true)
                 .add(LINE_ITEM_TYPE.getLabel(), LINE_ITEM_TYPE.getType(), true);
 
-        for (EnrichmentModule module : config.getModules()) {
+        for (EnrichmentModule module : modules) {
             for (Column c : module.columnsAdded()) {
                 schema = schema.add(c.getLabel(), c.getType(), true);
             }
@@ -75,7 +124,7 @@ public void testPipelineEnrichmentLogic(String lineItemType, boolean expectEnric
         assertEquals("us-east-1", PRODUCT_REGION_CODE.getString(processedRow));
 
         // Verify enrichment logic
-        for (EnrichmentModule module : config.getModules()) {
+        for (EnrichmentModule module : modules) {
             for (Column c : module.columnsAdded()) {
                 int fieldIndex = processedRow.fieldIndex(c.getLabel());
                 if (expectEnrichment) {