LibJS: Add %TypedArray%.prototype.indexOf

Userland/Libraries/LibJS/Runtime/TypedArrayPrototype.cpp

@@ -35,6 +35,7 @@ void TypedArrayPrototype::initialize(GlobalObject& object)
     define_native_function(vm.names.findIndex, find_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);
     define_native_function(vm.names.some, some, 1, attr);
     define_native_function(vm.names.join, join, 1, attr);
     define_native_function(vm.names.keys, keys, 0, attr);
@@ -308,6 +309,52 @@ JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::includes)
     return Value(false);
 }
 
+// 23.2.3.14 %TypedArray%.prototype.indexOf ( searchElement [ , fromIndex ] ), https://tc39.es/ecma262/#sec-%typedarray%.prototype.indexof
+JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::index_of)
+{
+    auto typed_array = typed_array_from(vm, global_object);
+    if (!typed_array)
+        return {};
+
+    auto length = typed_array->array_length();
+
+    if (length == 0)
+        return Value(-1);
+
+    auto n = vm.argument(1).to_integer_or_infinity(global_object);
+    if (vm.exception())
+        return {};
+
+    auto value_n = Value(n);
+    if (value_n.is_positive_infinity())
+        return Value(-1);
+    else if (value_n.is_negative_infinity())
+        n = 0;
+
+    u32 k;
+    if (n >= 0) {
+        k = n;
+    } else {
+        auto relative_k = length + n;
+        if (relative_k < 0)
+            relative_k = 0;
+        k = relative_k;
+    }
+
+    auto search_element = vm.argument(0);
+    for (; k < length; ++k) {
+        auto k_present = typed_array->has_property(k);
+        if (k_present) {
+            auto element_k = typed_array->get(k);
+
+            if (strict_eq(search_element, element_k))
+                return Value(k);
+        }
+    }
+
+    return Value(-1);
+}
+
 // 23.2.3.25 %TypedArray%.prototype.some ( callbackfn [ , thisArg ] ), https://tc39.es/ecma262/#sec-%typedarray%.prototype.some
 JS_DEFINE_NATIVE_FUNCTION(TypedArrayPrototype::some)
 {

Userland/Libraries/LibJS/Runtime/TypedArrayPrototype.h

@@ -32,6 +32,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(find_index);
     JS_DECLARE_NATIVE_FUNCTION(for_each);
     JS_DECLARE_NATIVE_FUNCTION(includes);
+    JS_DECLARE_NATIVE_FUNCTION(index_of);
     JS_DECLARE_NATIVE_FUNCTION(some);
     JS_DECLARE_NATIVE_FUNCTION(join);
     JS_DECLARE_NATIVE_FUNCTION(keys);

Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.indexOf.js

@@ -0,0 +1,44 @@
+const TYPED_ARRAYS = [
+    Uint8Array,
+    Uint8ClampedArray,
+    Uint16Array,
+    Uint32Array,
+    Int8Array,
+    Int16Array,
+    Int32Array,
+    Float32Array,
+    Float64Array,
+];
+
+const BIGINT_TYPED_ARRAYS = [BigUint64Array, BigInt64Array];
+
+test("basic functionality", () => {
+    TYPED_ARRAYS.forEach(T => {
+        expect(T.prototype.indexOf).toHaveLength(1);
+
+        const typedArray = new T(3);
+        typedArray[0] = 1;
+        typedArray[1] = 2;
+        typedArray[2] = 3;
+
+        expect(typedArray.indexOf(2)).toBe(1);
+        expect(typedArray.indexOf(-1)).toBe(-1);
+        expect(typedArray.indexOf(Infinity)).toBe(-1);
+        expect(typedArray.indexOf(2, 2)).toBe(-1);
+        expect(typedArray.indexOf(2, -2)).toBe(1);
+    });
+
+    BIGINT_TYPED_ARRAYS.forEach(T => {
+        expect(T.prototype.indexOf).toHaveLength(1);
+
+        const typedArray = new T(3);
+        typedArray[0] = 1n;
+        typedArray[1] = 2n;
+        typedArray[2] = 3n;
+
+        expect(typedArray.indexOf(2n)).toBe(1);
+        expect(typedArray.indexOf(-1n)).toBe(-1);
+        expect(typedArray.indexOf(2n, 2)).toBe(-1);
+        expect(typedArray.indexOf(2n, -2)).toBe(1);
+    });
+});