RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-27 13:27:35 +00:00
Code Issues Activity Actions

LibJS: Implement proposed TypedArray.prototype.findLast{,Index}

Browse source 
Proposal: https://tc39.es/proposal-array-find-from-last/
This commit is contained in:
davidot 2021-08-06 15:39:25 +02:00 • committed by Linus Groh
parent b6523906b3
commit 871a29884d
4 changed files with 302 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

58
Userland/Libraries/LibJS/Runtime/TypedArrayPrototype.cpp
View file

@ -34,6 +34,8 @@ void TypedArrayPrototype::initialize(GlobalObject& object)
define_native_function(vm.names.fill, fill, 1, attr);
define_native_function(vm.names.find, find, 1, attr);
define_native_function(vm.names.findIndex, find_index, 1, attr);
define_native_function(vm.names.findLast, find_last, 1, attr);
define_native_function(vm.names.findLastIndex, find_last_index, 1, attr);
define_native_function(vm.names.forEach, for_each, 1, attr);
define_native_function(vm.names.includes, includes, 1, attr);
define_native_function(vm.names.indexOf, index_of, 1, attr);
@ -129,6 +131,34 @@ static void for_each_item(VM& vm, GlobalObject& global_object, const String& nam
}
}
static void for_each_item_from_last(VM& vm, GlobalObject& global_object, const String& name, Function<IterationDecision(size_t index, Value value, Value callback_result)> callback)
{
auto* typed_array = validate_typed_array_from_this(global_object);
if (!typed_array)
return;
auto initial_length = typed_array->array_length();
auto* callback_function = callback_from_args(global_object, name);
if (!callback_function)
return;
auto this_value = vm.argument(1);
for (ssize_t i = (ssize_t)initial_length - 1; i >= 0; --i) {
auto value = typed_array->get(i);
if (vm.exception())
return;
auto callback_result = vm.call(*callback_function, this_value, value, Value((i32)i), typed_array);
if (vm.exception())
return;
if (callback(i, value, callback_result) == IterationDecision::Break)
break;
}
}
// 23.2.4.1 TypedArraySpeciesCreate ( exemplar, argumentList ), https://tc39.es/ecma262/#typedarray-species-create
static TypedArrayBase* typed_array_species_create(GlobalObject& global_object, TypedArrayBase const& exemplar, MarkedValueList arguments)
{
@ -303,6 +333,34 @@ JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::find_index)
return Value(result_index);
}
// 4 %TypedArray%.prototype.findLast ( predicate [ , thisArg ] ), https://tc39.es/proposal-array-find-from-last/index.html#sec-%typedarray%.prototype.findlast
JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::find_last)
{
auto result = js_undefined();
for_each_item_from_last(vm, global_object, "findLast", [&](auto, auto value, auto callback_result) {
if (callback_result.to_boolean()) {
result = value;
return IterationDecision::Break;
}
return IterationDecision::Continue;
});
return result;
}
// 5 %TypedArray%.prototype.findLastIndex ( predicate [ , thisArg ] ), https://tc39.es/proposal-array-find-from-last/index.html#sec-%typedarray%.prototype.findlastindex
JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::find_last_index)
{
auto result_index = -1;
for_each_item_from_last(vm, global_object, "findLastIndex", [&](auto index, auto, auto callback_result) {
if (callback_result.to_boolean()) {
result_index = index;
return IterationDecision::Break;
}
return IterationDecision::Continue;
});
return Value(result_index);
}
// 23.2.3.12 %TypedArray%.prototype.forEach ( callbackfn [ , thisArg ] ), https://tc39.es/ecma262/#sec-%typedarray%.prototype.foreach
JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::for_each)
{

2
Userland/Libraries/LibJS/Runtime/TypedArrayPrototype.h
View file

@ -30,6 +30,8 @@ private:
JS_DECLARE_NATIVE_FUNCTION(fill);
JS_DECLARE_NATIVE_FUNCTION(find);
JS_DECLARE_NATIVE_FUNCTION(find_index);
JS_DECLARE_NATIVE_FUNCTION(find_last);
JS_DECLARE_NATIVE_FUNCTION(find_last_index);
JS_DECLARE_NATIVE_FUNCTION(for_each);
JS_DECLARE_NATIVE_FUNCTION(includes);
JS_DECLARE_NATIVE_FUNCTION(index_of);