Add ReverseFilter tests for primitive and object arrays; fix ReverseFilter for primitive arrays

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: jasmith-hs

src/main/java/com/hubspot/jinjava/lib/filter/ReverseFilter.java

@@ -20,6 +20,7 @@
 import com.hubspot.jinjava.doc.annotations.JinjavaSnippet;
 import com.hubspot.jinjava.interpret.JinjavaInterpreter;
 import com.hubspot.jinjava.objects.collections.ArrayBacked;
+import java.lang.reflect.Array;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
@@ -54,7 +55,7 @@ public Object filter(Object object, JinjavaInterpreter interpreter, String... ar
     }
     // array
     if (object.getClass().isArray()) {
-      return ReverseArrayIterator.create((Object[]) object);
+      return ReverseArrayIterator.create(object);
     }
     // string
     if (object instanceof String) {
@@ -76,26 +77,26 @@ public String getName() {
     return "reverse";
   }
 
-  static class ReverseArrayIterator<T> implements Iterator<T>, ArrayBacked<T> {
+  static class ReverseArrayIterator implements Iterator<Object>, ArrayBacked {
 
-    private final T[] array;
+    private final Object array;
     private int index;
 
-    static <T> ReverseArrayIterator<T> create(T[] array) {
-      return new ReverseArrayIterator<>(array);
+    static ReverseArrayIterator create(Object array) {
+      return new ReverseArrayIterator(array);
     }
 
-    private ReverseArrayIterator(T[] array) {
+    private ReverseArrayIterator(Object array) {
       this.array = array;
-      index = array.length - 1;
+      index = Array.getLength(array) - 1;
     }
 
     @Override
-    public T next() {
+    public Object next() {
       if (index < 0) {
         throw new NoSuchElementException();
       }
-      return array[index--];
+      return Array.get(array, index--);
     }
 
     @Override
@@ -104,7 +105,7 @@ public boolean hasNext() {
     }
 
     @Override
-    public T[] backingArray() {
+    public Object backingArray() {
       return array;
     }
   }

src/main/java/com/hubspot/jinjava/objects/collections/ArrayBacked.java

@@ -1,5 +1,5 @@
 package com.hubspot.jinjava.objects.collections;
 
-public interface ArrayBacked<T> {
-  T[] backingArray();
+public interface ArrayBacked {
+  Object backingArray();
 }

src/main/java/com/hubspot/jinjava/util/EagerExpressionResolver.java

@@ -329,7 +329,7 @@ private static boolean isResolvableObjectRec(
     if (isPrimitive(val)) {
       return true;
     }
-    if (val instanceof ArrayBacked<?> arrayBacked) {
+    if (val instanceof ArrayBacked arrayBacked) {
       val = arrayBacked.backingArray();
     }
     try {

src/test/java/com/hubspot/jinjava/lib/filter/ReverseFilterTest.java

@@ -0,0 +1,31 @@
+package com.hubspot.jinjava.lib.filter;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.hubspot.jinjava.BaseJinjavaTest;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.Test;
+
+public class ReverseFilterTest extends BaseJinjavaTest {
+
+  @Test
+  public void itReversesPrimitiveIntArray() {
+    Map<String, Object> context = new HashMap<>();
+    context.put("arr", new int[] { 1, 2, 3 });
+    assertThat(
+      jinjava.render("{% for item in arr|reverse %}{{ item }}{% endfor %}", context)
+    )
+      .isEqualTo("321");
+  }
+
+  @Test
+  public void itReversesObjectArray() {
+    Map<String, Object> context = new HashMap<>();
+    context.put("arr", new String[] { "a", "b", "c" });
+    assertThat(
+      jinjava.render("{% for item in arr|reverse %}{{ item }}{% endfor %}", context)
+    )
+      .isEqualTo("cba");
+  }
+}