Implement debug object indexed elements type function

cli/src/debug/object.rs

@@ -1,6 +1,7 @@
 use boa_engine::{
-    js_string, object::ObjectInitializer, Context, JsNativeError, JsObject, JsResult, JsValue,
-    NativeFunction,
+    js_string,
+    object::{IndexProperties, ObjectInitializer},
+    Context, JsNativeError, JsObject, JsResult, JsValue, NativeFunction,
 };
 
 /// Returns objects pointer in memory.
@@ -21,8 +22,36 @@ fn id(_: &JsValue, args: &[JsValue], _: &mut Context) -> JsResult<JsValue> {
     Ok(js_string!(format!("0x{:X}", ptr.cast::<()>() as usize)).into())
 }
 
+/// Returns objects pointer in memory.
+fn indexed_elements_type(_: &JsValue, args: &[JsValue], _: &mut Context) -> JsResult<JsValue> {
+    let Some(value) = args.first() else {
+        return Err(JsNativeError::typ()
+            .with_message("expected object argument")
+            .into());
+    };
+
+    let Some(object) = value.as_object() else {
+        return Err(JsNativeError::typ()
+            .with_message(format!("expected object, got {}", value.type_of()))
+            .into());
+    };
+
+    let typ = match object.borrow().properties().index_properties() {
+        IndexProperties::DenseI32(_) => "DenseI32",
+        IndexProperties::DenseF64(_) => "DenseF64",
+        IndexProperties::DenseElement(_) => "DenseElement",
+        IndexProperties::Sparse(_) => "SparseElement",
+    };
+    Ok(js_string!(typ).into())
+}
+
 pub(super) fn create_object(context: &mut Context) -> JsObject {
     ObjectInitializer::new(context)
         .function(NativeFunction::from_fn_ptr(id), js_string!("id"), 1)
+        .function(
+            NativeFunction::from_fn_ptr(indexed_elements_type),
+            js_string!("indexedElementsType"),
+            1,
+        )
         .build()
 }

core/engine/src/object/property_map.rs

@@ -943,6 +943,7 @@ impl FusedIterator for IndexPropertyKeys<'_> {}
 
 /// An iterator over the index values (`Property`) of an `Object`.
 #[derive(Debug, Clone)]
+#[allow(variant_size_differences)]
 pub enum IndexPropertyValues<'a> {
     /// An iterator over dense, Vec backed indexed property entries of an `Object`.
     DenseI32(std::slice::Iter<'a, i32>),

docs/boa_object.md

@@ -163,6 +163,30 @@ $boa.object.id(o)    // '0x7F5B3251B718'
 $boa.object.id($boa) // '0x7F5B3251B5D8'
 ```
 
+## Function `$boa.object.indexedStorageType(object)`
+
+This function returns indexed storage type.
+
+Example:
+
+```JavaScript
+let a = [1, 2]
+
+$boa.object.indexedStorageType(a) // 'DenseI32'
+
+a.push(0xdeadbeef)
+$boa.object.indexedStorageType(a) // 'DenseI32'
+
+a.push(0.5)
+$boa.object.indexedStorageType(a) // 'DenseF64'
+
+a.push("Hello")
+$boa.object.indexedStorageType(a) // 'DenseElement'
+
+a[100] = 100 // Make a hole
+$boa.object.indexedStorageType(a) // 'SparseElement'
+```
+
 ## Module `$boa.optimizer`
 
 This modules contains getters and setters for enabling and disabling optimizations.