Method checkArguments

checker/checker.go:1050–1173

(
	name string,
	fn Nature,
	arguments []ast.Node,
	node ast.Node,
)

}

func (v *Checker) checkArguments(
	name string,
	fn Nature,
	arguments []ast.Node,
	node ast.Node,
) (Nature, *file.Error) {
	if fn.IsUnknown(&v.config.NtCache) {
		return Nature{}, nil
	}

	numOut := fn.NumOut()
	if numOut == 0 {
		return Nature{}, &file.Error{
			Location: node.Location(),
			Message:  fmt.Sprintf("func %v doesn't return value", name),
		}
	}
	if numOut > 2 {
		return Nature{}, &file.Error{
			Location: node.Location(),
			Message:  fmt.Sprintf("func %v returns more then two values", name),
		}
	}

	// If func is method on an env, first argument should be a receiver,
	// and actual arguments less than fnNumIn by one.
	fnNumIn := fn.NumIn()
	if fn.Method { // TODO: Move subtraction to the Nature.NumIn() and Nature.In() methods.
		fnNumIn--
	}
	// Skip first argument in case of the receiver.
	fnInOffset := 0
	if fn.Method {
		fnInOffset = 1
	}

	var err *file.Error
	isVariadic := fn.IsVariadic()
	if isVariadic {
		if len(arguments) < fnNumIn-1 {
			err = &file.Error{
				Location: node.Location(),
				Message:  fmt.Sprintf("not enough arguments to call %v", name),
			}
		}
	} else {
		if len(arguments) > fnNumIn {
			err = &file.Error{
				Location: node.Location(),
				Message:  fmt.Sprintf("too many arguments to call %v", name),
			}
		}
		if len(arguments) < fnNumIn {
			err = &file.Error{
				Location: node.Location(),
				Message:  fmt.Sprintf("not enough arguments to call %v", name),
			}
		}