src/Utils/DatePicker.php
public function isDateSelected()
    {
        $value = $this->datePicker(['getDate']);
        $initial = $this->execute($this->date);

        // By some reasons DatePicker could not return a date using "getDate" method
        // and we'll try to use it from input value directly. An issue could occur
        // after saving the form and/or reloading the page.
        if (empty($value)) {
            $value = $this->execute(self::jsDate($this->element->getValue()));
        }

        self::debug(['Comparing "%s" with "%s".'], [$value, $initial]);

        if ($value !== $initial) {
            throw new \Exception(sprintf('DatePicker contains the "%s" but should "%s".', $value, $initial));
        }

        return $this;
    }
public function isDateSelected()
    {
        $value = $this->datePicker(['getDate']);
        $initial = $this->execute($this->date);

        // By some reasons DatePicker could not return a date using "getDate" method
        // and we'll try to use it from input value directly. An issue could occur
        // after saving the form and/or reloading the page.
        if (empty($value)) {
            $value = $this->execute(self::jsDate($this->element->getValue()));
        }

        self::debug(['Comparing "%s" with "%s".'], [$value, $initial]);

        if ($value !== $initial) {
            throw new \Exception(sprintf('DatePicker contains the "%s" but should "%s".', $value, $initial));
        }

        return $this;
    }
@throws \Exception

@return self