Implemented {Array,%TypedArray%}.prototype.{findLast,findLastIndex}() (#444)

Co-authored-by: notsatvrn <[email protected]>

builtin_array.go

@@ -1114,6 +1114,46 @@ func (r *Runtime) arrayproto_findIndex(call FunctionCall) Value {
 	return intToValue(-1)
 }
 
+func (r *Runtime) arrayproto_findLast(call FunctionCall) Value {
+	o := call.This.ToObject(r)
+	l := toLength(o.self.getStr("length", nil))
+	predicate := r.toCallable(call.Argument(0))
+	fc := FunctionCall{
+		This:      call.Argument(1),
+		Arguments: []Value{nil, nil, o},
+	}
+	for k := int64(l - 1); k >= 0; k-- {
+		idx := valueInt(k)
+		kValue := o.self.getIdx(idx, nil)
+		fc.Arguments[0], fc.Arguments[1] = kValue, idx
+		if predicate(fc).ToBoolean() {
+			return kValue
+		}
+	}
+
+	return _undefined
+}
+
+func (r *Runtime) arrayproto_findLastIndex(call FunctionCall) Value {
+	o := call.This.ToObject(r)
+	l := toLength(o.self.getStr("length", nil))
+	predicate := r.toCallable(call.Argument(0))
+	fc := FunctionCall{
+		This:      call.Argument(1),
+		Arguments: []Value{nil, nil, o},
+	}
+	for k := int64(l - 1); k >= 0; k-- {
+		idx := valueInt(k)
+		kValue := o.self.getIdx(idx, nil)
+		fc.Arguments[0], fc.Arguments[1] = kValue, idx
+		if predicate(fc).ToBoolean() {
+			return idx
+		}
+	}
+
+	return intToValue(-1)
+}
+
 func (r *Runtime) arrayproto_flat(call FunctionCall) Value {
 	o := call.This.ToObject(r)
 	l := toLength(o.self.getStr("length", nil))
@@ -1369,6 +1409,8 @@ func (r *Runtime) createArrayProto(val *Object) objectImpl {
 	o._putProp("filter", r.newNativeFunc(r.arrayproto_filter, nil, "filter", nil, 1), true, false, true)
 	o._putProp("find", r.newNativeFunc(r.arrayproto_find, nil, "find", nil, 1), true, false, true)
 	o._putProp("findIndex", r.newNativeFunc(r.arrayproto_findIndex, nil, "findIndex", nil, 1), true, false, true)
+	o._putProp("findLast", r.newNativeFunc(r.arrayproto_findLast, nil, "findLast", nil, 1), true, false, true)
+	o._putProp("findLastIndex", r.newNativeFunc(r.arrayproto_findLastIndex, nil, "findLastIndex", nil, 1), true, false, true)
 	o._putProp("flat", r.newNativeFunc(r.arrayproto_flat, nil, "flat", nil, 0), true, false, true)
 	o._putProp("flatMap", r.newNativeFunc(r.arrayproto_flatMap, nil, "flatMap", nil, 1), true, false, true)
 	o._putProp("forEach", r.newNativeFunc(r.arrayproto_forEach, nil, "forEach", nil, 1), true, false, true)
@@ -1401,6 +1443,8 @@ func (r *Runtime) createArrayProto(val *Object) objectImpl {
 	bl.setOwnStr("fill", valueTrue, true)
 	bl.setOwnStr("find", valueTrue, true)
 	bl.setOwnStr("findIndex", valueTrue, true)
+	bl.setOwnStr("findLast", valueTrue, true)
+	bl.setOwnStr("findLastIndex", valueTrue, true)
 	bl.setOwnStr("flat", valueTrue, true)
 	bl.setOwnStr("flatMap", valueTrue, true)
 	bl.setOwnStr("includes", valueTrue, true)

builtin_typedarrays.go

@@ -574,6 +574,54 @@ func (r *Runtime) typedArrayProto_findIndex(call FunctionCall) Value {
 	panic(r.NewTypeError("Method TypedArray.prototype.findIndex called on incompatible receiver %s", r.objectproto_toString(FunctionCall{This: call.This})))
 }
 
+func (r *Runtime) typedArrayProto_findLast(call FunctionCall) Value {
+	if ta, ok := r.toObject(call.This).self.(*typedArrayObject); ok {
+		ta.viewedArrayBuf.ensureNotDetached(true)
+		predicate := r.toCallable(call.Argument(0))
+		fc := FunctionCall{
+			This:      call.Argument(1),
+			Arguments: []Value{nil, nil, call.This},
+		}
+		for k := ta.length - 1; k >= 0; k-- {
+			var val Value
+			if ta.isValidIntegerIndex(k) {
+				val = ta.typedArray.get(ta.offset + k)
+			}
+			fc.Arguments[0] = val
+			fc.Arguments[1] = intToValue(int64(k))
+			if predicate(fc).ToBoolean() {
+				return val
+			}
+		}
+		return _undefined
+	}
+	panic(r.NewTypeError("Method TypedArray.prototype.findLast called on incompatible receiver %s", r.objectproto_toString(FunctionCall{This: call.This})))
+}
+
+func (r *Runtime) typedArrayProto_findLastIndex(call FunctionCall) Value {
+	if ta, ok := r.toObject(call.This).self.(*typedArrayObject); ok {
+		ta.viewedArrayBuf.ensureNotDetached(true)
+		predicate := r.toCallable(call.Argument(0))
+		fc := FunctionCall{
+			This:      call.Argument(1),
+			Arguments: []Value{nil, nil, call.This},
+		}
+		for k := ta.length - 1; k >= 0; k-- {
+			if ta.isValidIntegerIndex(k) {
+				fc.Arguments[0] = ta.typedArray.get(ta.offset + k)
+			} else {
+				fc.Arguments[0] = _undefined
+			}
+			fc.Arguments[1] = intToValue(int64(k))
+			if predicate(fc).ToBoolean() {
+				return fc.Arguments[1]
+			}
+		}
+		return intToValue(-1)
+	}
+	panic(r.NewTypeError("Method TypedArray.prototype.findLastIndex called on incompatible receiver %s", r.objectproto_toString(FunctionCall{This: call.This})))
+}
+
 func (r *Runtime) typedArrayProto_forEach(call FunctionCall) Value {
 	if ta, ok := r.toObject(call.This).self.(*typedArrayObject); ok {
 		ta.viewedArrayBuf.ensureNotDetached(true)
@@ -1447,6 +1495,8 @@ func (r *Runtime) createTypedArrayProto(val *Object) objectImpl {
 	b._putProp("filter", r.newNativeFunc(r.typedArrayProto_filter, nil, "filter", nil, 1), true, false, true)
 	b._putProp("find", r.newNativeFunc(r.typedArrayProto_find, nil, "find", nil, 1), true, false, true)
 	b._putProp("findIndex", r.newNativeFunc(r.typedArrayProto_findIndex, nil, "findIndex", nil, 1), true, false, true)
+	b._putProp("findLast", r.newNativeFunc(r.typedArrayProto_findLast, nil, "findLast", nil, 1), true, false, true)
+	b._putProp("findLastIndex", r.newNativeFunc(r.typedArrayProto_findLastIndex, nil, "findLastIndex", nil, 1), true, false, true)
 	b._putProp("forEach", r.newNativeFunc(r.typedArrayProto_forEach, nil, "forEach", nil, 1), true, false, true)
 	b._putProp("includes", r.newNativeFunc(r.typedArrayProto_includes, nil, "includes", nil, 1), true, false, true)
 	b._putProp("indexOf", r.newNativeFunc(r.typedArrayProto_indexOf, nil, "indexOf", nil, 1), true, false, true)

tc39_test.go

@@ -265,7 +265,6 @@ var (
 		"generators",
 		"String.prototype.replaceAll",
 		"resizable-arraybuffer",
-		"array-find-from-last",
 		"regexp-named-groups",
 		"regexp-dotall",
 		"regexp-unicode-property-escapes",