Select2Context.php

<?php
class Select2Context{
  
    public function iCompleteSelect2($term, $field, $entry)
    {
        if (!($driver = $this->getDriver()) instanceof Selenium2Driver) {
            throw new \InvalidArgumentException('Don\'t use select2 in non-selenium env');
        }
        $this->openField($field);
        $this->fillSearchField($field, $term);
        $this->selectValue($field, $entry);
    }

    /**
     *
     * @param string $field
     * @throws \Exception
     */
    private function openField($field)
    {
        $this->getDriver()->evaluateScript(sprintf('$("#%s").select2("open");', $field));
    }

    /**
     * Fill Select2 search field
     *
     * @param string $field
     * @param string $value
     * @throws \Exception
     */
    private function fillSearchField($field, $value)
    {
        $driver = $this->getDriver();
        // Can't use `$this->getSession()->getPage()->find()` because of https://github.com/minkphp/MinkSelenium2Driver/issues/188
        $select2Input = $driver->getWebDriverSession()->element(LocatorStrategy::CSS_SELECTOR, ".select2-container--open .select2-search__field");
        if (!$select2Input) {
            throw new \Exception(sprintf('No field "%s" found', $field));
        }
        $chars = str_split($value);
        foreach($chars as $char){
            $select2Input->postValue(['value' => [$char]]);
        }
        //so async
        sleep('5');
        //$this->getSession()->wait(10000, '(0 === jQuery.active)');
    }

    /**
     * @param string $field
     * @param string $value
     * @throws \Exception
     */
    private function selectValue($field, $value)
    {
        $chosenResults = $this->findElements('.select2-results__option--highlighted');
        foreach ($chosenResults as $result) {
            if ($result->getText() == $value) {
                $result->click();
                return;
            }
        }

        throw new \Exception(sprintf('Value "%s" not found for "%s"', $value, $field));
    }
}