LibWeb/IDB: Implement IDBIndex::get

Author: https://github.com/stelar7
Commit: e74e571b56
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4727
Reviewed-by: https://github.com/gmta ✅
Reviewed-by: https://github.com/shannonbooth

Libraries/LibWeb/IndexedDB/Internal/Algorithms.cpp

@@ -1929,4 +1929,21 @@ GC::Ref<JS::Array> retrieve_multiple_keys_from_an_object_store(JS::Realm& realm,
     return list;
 }
 
+// https://w3c.github.io/IndexedDB/#retrieve-a-referenced-value-from-an-index
+JS::Value retrieve_a_referenced_value_from_an_index(JS::Realm& realm, GC::Ref<Index> index, GC::Ref<IDBKeyRange> range)
+{
+    // 1. Let record be the first record in index’s list of records whose key is in range, if any.
+    auto record = index->first_in_range(range);
+
+    // 2. If record was not found, return undefined.
+    if (!record.has_value())
+        return JS::js_undefined();
+
+    // 3. Let serialized be record’s referenced value.
+    auto serialized = index->referenced_value(*record);
+
+    // 4. Return ! StructuredDeserialize(serialized, targetRealm).
+    return MUST(HTML::structured_deserialize(realm.vm(), serialized, realm));
+}
+
 }

Libraries/LibWeb/IndexedDB/Internal/Algorithms.h

@@ -9,6 +9,7 @@
 #include <AK/Variant.h>
 #include <LibJS/Runtime/Realm.h>
 #include <LibWeb/HTML/DOMStringList.h>
+#include <LibWeb/IndexedDB/IDBKeyRange.h>
 #include <LibWeb/IndexedDB/IDBRequest.h>
 #include <LibWeb/IndexedDB/Internal/Key.h>
 #include <LibWeb/StorageAPI/StorageKey.h>
@@ -50,5 +51,6 @@ JS::Value clear_an_object_store(GC::Ref<ObjectStore>);
 JS::Value retrieve_a_key_from_an_object_store(JS::Realm&, GC::Ref<ObjectStore>, GC::Ref<IDBKeyRange>);
 GC::Ref<JS::Array> retrieve_multiple_values_from_an_object_store(JS::Realm&, GC::Ref<ObjectStore>, GC::Ref<IDBKeyRange>, Optional<WebIDL::UnsignedLong>);
 GC::Ref<JS::Array> retrieve_multiple_keys_from_an_object_store(JS::Realm&, GC::Ref<ObjectStore>, GC::Ref<IDBKeyRange>, Optional<WebIDL::UnsignedLong>);
+JS::Value retrieve_a_referenced_value_from_an_index(JS::Realm&, GC::Ref<Index>, GC::Ref<IDBKeyRange>);
 
 }

Libraries/LibWeb/IndexedDB/Internal/Index.cpp

@@ -76,4 +76,11 @@ void Index::clear_records()
     m_records.clear();
 }
 
+Optional<IndexRecord&> Index::first_in_range(GC::Ref<IDBKeyRange> range)
+{
+    return m_records.first_matching([&](auto const& record) {
+        return range->is_in_range(record.key);
+    });
+}
+
 }

Libraries/LibWeb/IndexedDB/Internal/Index.h

@@ -41,6 +41,7 @@ public:
 
     [[nodiscard]] bool has_record_with_key(GC::Ref<Key> key);
     void clear_records();
+    Optional<IndexRecord&> first_in_range(GC::Ref<IDBKeyRange> range);
 
     HTML::SerializationRecord referenced_value(IndexRecord const& index_record) const;