behat_config_util.php

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Utils to set Behat config
 *
 * @package    core
 * @copyright  2016 Rajesh Taneja
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

require_once(__DIR__ . '/../lib.php');
require_once(__DIR__ . '/behat_command.php');
require_once(__DIR__ . '/../../testing/classes/tests_finder.php');

/**
 * Behat configuration manager
 *
 * Creates/updates Behat config files getting tests
 * and steps from Moodle codebase
 *
 * @package    core
 * @copyright  2016 Rajesh Taneja
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class behat_config_util {

    /**
     * @var array list of features in core.
     */
    private $features;

    /**
     * @var array list of contexts in core.
     */
    private $contexts;

    /**
     * @var array list of theme specific contexts.
     */
    private $themecontexts;

    /**
     * @var array list of overridden theme contexts.
     */
    private $overriddenthemescontexts;

    /**
     * @var array list of components with tests.
     */
    private $componentswithtests;

    /**
     * @var bool keep track of theme to return suite with all core features included or not.
     */
    private $themesuitewithallfeatures = false;

    /**
     * @var string filter features which have tags.
     */
    private $tags = '';

    /**
     * @var int number of parallel runs.
     */
    private $parallelruns = 0;

    /**
     * @var int current run.
     */
    private $currentrun = 0;

    /**
     * Set value for theme suite to include all core features. This should be used if your want all core features to be
     * run with theme.
     *
     * @param bool $val
     */
    public function set_theme_suite_to_include_core_features($val) {
        $this->themesuitewithallfeatures = $val;
    }

    /**
     * Set the value for tags, so features which are returned will be using filtered by this.
     *
     * @param string $tags
     */
    public function set_tag_for_feature_filter($tags) {
        $this->tags = $tags;
    }

    /**
     * Set parallel run to be used for generating config.
     *
     * @param int $parallelruns number of parallel runs.
     * @param int $currentrun current run
     */
    public function set_parallel_run($parallelruns, $currentrun) {

        if ($parallelruns < $currentrun) {
            behat_error(BEHAT_EXITCODE_REQUIREMENT,
                'Parallel runs('.$parallelruns.') should be more then current run('.$currentrun.')');
        }

        $this->parallelruns = $parallelruns;
        $this->currentrun = $currentrun;
    }

    /**
     * Return parallel runs
     *
     * @return int number of parallel runs.
     */
    public function get_number_of_parallel_run() {
        // Get number of parallel runs if not passed.
        if (empty($this->parallelruns) && ($this->parallelruns !== false)) {
            $this->parallelruns = behat_config_manager::get_parallel_test_runs();
        }

        return $this->parallelruns;
    }

    /**
     * Return current run
     *
     * @return int current run.
     */
    public function get_current_run() {
        global $CFG;

        // Get number of parallel runs if not passed.
        if (empty($this->currentrun) && ($this->currentrun !== false) && !empty($CFG->behatrunprocess)) {
            $this->currentrun = $CFG->behatrunprocess;
        }

        return $this->currentrun;
    }

    /**
     * Return list of features.
     *
     * @param string $tags tags.
     * @return array
     */
    public function get_components_features($tags = '') {
        global $CFG;

        // If we already have a list created then just return that, as it's up-to-date.
        // If tags are passed then it's a new filter of features we need.
        if (!empty($this->features) && empty($tags)) {
            return $this->features;
        }

        // Gets all the components with features.
        $features = array();
        $featurespaths = array();
        $components = $this->get_components_with_tests();

        if ($components) {
            foreach ($components as $componentname => $path) {
                $path = $this->clean_path($path) . self::get_behat_tests_path();
                if (empty($featurespaths[$path]) && file_exists($path)) {
                    list($key, $featurepath) = $this->get_clean_feature_key_and_path($path);
                    $featurespaths[$key] = $featurepath;
                }
            }
            foreach ($featurespaths as $path) {
                $additional = glob("$path/*.feature");

                $additionalfeatures = array();
                foreach ($additional as $featurepath) {
                    list($key, $path) = $this->get_clean_feature_key_and_path($featurepath);
                    $additionalfeatures[$key] = $path;
                }

                $features = array_merge($features, $additionalfeatures);
            }
        }

        // Optionally include features from additional directories.
        if (!empty($CFG->behat_additionalfeatures)) {
            $additional = array_map("realpath", $CFG->behat_additionalfeatures);
            $additionalfeatures = array();
            foreach ($additional as $featurepath) {
                list($key, $path) = $this->get_clean_feature_key_and_path($featurepath);
                $additionalfeatures[$key] = $path;
            }
            $features = array_merge($features, $additionalfeatures);
        }

        $this->features = $features;

        return $this->filtered_features_with_tags($features, $tags);
    }

    /**
     * Return feature key for featurepath
     *
     * @param string $featurepath
     * @return array key and featurepath.
     */
    public function get_clean_feature_key_and_path($featurepath) {
        global $CFG;

        // Fix directory path.
        $featurepath = str_replace('\\', DIRECTORY_SEPARATOR, $featurepath);
        $featurepath = str_replace('/', DIRECTORY_SEPARATOR, $featurepath);

        if (testing_is_cygwin()) {
            $featurepath = str_replace('\\', '/', $featurepath);
        }

        $key = basename($featurepath, '.feature');

        // Get relative path.
        $featuredirname = str_replace($CFG->dirroot . DIRECTORY_SEPARATOR , '', $featurepath);
        // Get 5 levels of feature path to ensure we have a unique key.
        for ($i = 0; $i < 5; $i++) {
            if (($featuredirname = dirname($featuredirname)) && $featuredirname !== '.') {
                if ($basename = basename($featuredirname)) {
                    $key .= '_' . $basename;
                }
            }
        }

        return array($key, $featurepath);
    }

    /**
     * Get component contexts.
     *
     * @param string $component component name.
     * @return array
     */
    private function get_component_contexts($component) {

        if (empty($component)) {
            return $this->contexts;
        }

        $componentcontexts = array();
        foreach ($this->contexts as $key => $path) {
            if ($component == '' || $component === $key) {
                $componentcontexts[$key] = $path;
            }
        }

        return $componentcontexts;
    }

    /**
     * Gets the list of Moodle behat contexts
     *
     * Class name as a key and the filepath as value
     *
     * Externalized from update_config_file() to use
     * it from the steps definitions web interface
     *
     * @param  string $component Restricts the obtained steps definitions to the specified component
     * @return array
     */
    public function get_components_contexts($component = '') {

        // If we already have a list created then just return that, as it's up-to-date.
        if (!empty($this->contexts)) {
            return $this->get_component_contexts($component);
        }

        $components = $this->get_components_with_tests();

        $this->contexts = array();
        foreach ($components as $componentname => $componentpath) {
            $componentpath = self::clean_path($componentpath);

            if (!file_exists($componentpath . self::get_behat_tests_path())) {
                continue;
            }
            $diriterator = new DirectoryIterator($componentpath . self::get_behat_tests_path());
            $regite = new RegexIterator($diriterator, '|behat_.*\.php$|');

            // All behat_*.php inside self::get_behat_tests_path() are added as steps definitions files.
            foreach ($regite as $file) {
                $key = $file->getBasename('.php');
                $this->contexts[$key] = $file->getPathname();
            }
        }

        return $this->get_component_contexts($component);
    }

    /**
     * Behat config file specifing the main context class,
     * the required Behat extensions and Moodle test wwwroot.
     *
     * @param array $features The system feature files
     * @param array $contexts The system steps definitions
     * @param string $tags filter features with specified tags.
     * @param int $parallelruns number of parallel runs.
     * @param int $currentrun current run for which config file is needed.
     * @return string
     */
    public function get_config_file_contents($features = '', $contexts = '', $tags = '', $parallelruns = 0, $currentrun = 0) {
        global $CFG;

        // Set current run and parallel run.
        if (!empty($parallelruns) && !empty($currentrun)) {
            $this->set_parallel_run($parallelruns, $currentrun);
        }

        // If tags defined then use them. This is for BC.
        if (!empty($tags)) {
            $this->set_tag_for_feature_filter($tags);
        }

        // If features not passed then get it. Empty array means we don't need to include features.
        if (empty($features) && !is_array($features)) {
            $features = $this->get_components_features();
        } else {
            $this->features = $features;
        }

        // If stepdefinitions not passed then get the list.
        if (empty($contexts)) {
            $this->get_components_contexts();
        } else {
            $this->contexts = $contexts;
        }

        // We require here when we are sure behat dependencies are available.
        require_once($CFG->dirroot . '/vendor/autoload.php');

        $config = $this->build_config();

        $config = $this->merge_behat_config($config);

        $config = $this->merge_behat_profiles($config);

        return Symfony\Component\Yaml\Yaml::dump($config, 10, 2);
    }

    /**
     * Search feature files for set of tags.
     *
     * @param array $features set of feature files.
     * @param string $tags list of tags (currently support && only.)
     * @return array filtered list of feature files with tags.
     */
    public function filtered_features_with_tags($features = '', $tags = '') {

        // This is for BC. Features if not passed then we already have a list in this object.
        if (empty($features)) {
            $features = $this->features;
        }

        // If no tags defined then return full list.
        if (empty($tags) && empty($this->tags)) {
            return $features;
        }

        // If no tags passed by the caller, then it's already set.
        if (empty($tags)) {
            $tags = $this->tags;
        }

        $newfeaturelist = array();
        // Split tags in and and or.
        $tags = explode('&&', $tags);
        $andtags = array();
        $ortags = array();
        foreach ($tags as $tag) {
            // Explode all tags seperated by , and add it to ortags.
            $ortags = array_merge($ortags, explode(',', $tag));
            // And tags will be the first one before comma(,).
            $andtags[] = preg_replace('/,.*/', '', $tag);
        }

        foreach ($features as $featurefile) {
            $contents = file_get_contents($featurefile);
            $includefeature = true;
            foreach ($andtags as $tag) {
                // If negitive tag, then ensure it don't exist.
                if (strpos($tag, '~') !== false) {
                    $tag = substr($tag, 1);
                    if ($contents && strpos($contents, $tag) !== false) {
                        $includefeature = false;
                        break;
                    }
                } else if ($contents && strpos($contents, $tag) === false) {
                    $includefeature = false;
                    break;
                }
            }

            // If feature not included then check or tags.
            if (!$includefeature && !empty($ortags)) {
                foreach ($ortags as $tag) {
                    if ($contents && (strpos($tag, '~') === false) && (strpos($contents, $tag) !== false)) {
                        $includefeature = true;
                        break;
                    }
                }
            }

            if ($includefeature) {
                $newfeaturelist[] = $featurefile;
            }
        }
        return $newfeaturelist;
    }

    /**
     * Build config for behat.yml.
     *
     * @param int $parallelruns how many parallel runs feature needs to be divided.
     * @param int $currentrun current run for which features should be returned.
     * @return array
     */
    protected function build_config($parallelruns = 0, $currentrun = 0) {
        global $CFG;

        if (!empty($parallelruns) && !empty($currentrun)) {
            $this->set_parallel_run($parallelruns, $currentrun);
        } else {
            $currentrun = $this->get_current_run();
            $parallelruns = $this->get_number_of_parallel_run();
        }

        $selenium2wdhost = array('wd_host' => 'http://localhost:4444/wd/hub');
        // If parallel run, then set wd_host if specified.
        if (!empty($currentrun) && !empty($parallelruns)) {
            // Set proper selenium2 wd_host if defined.
            if (!empty($CFG->behat_parallel_run[$currentrun - 1]['wd_host'])) {
                $selenium2wdhost = array('wd_host' => $CFG->behat_parallel_run[$currentrun - 1]['wd_host']);
            }
        }

        // It is possible that it has no value as we don't require a full behat setup to list the step definitions.
        if (empty($CFG->behat_wwwroot)) {
            $CFG->behat_wwwroot = 'http://itwillnotbeused.com';
        }

        $suites = $this->get_behat_suites($parallelruns, $currentrun);

        $overriddenthemescontexts = $this->get_overridden_theme_contexts();
        if (!empty($overriddenthemescontexts)) {
            $allcontexts = array_merge($this->contexts, $overriddenthemescontexts);
        } else {
            $allcontexts = $this->contexts;
        }

        // Remove selectors from step definitions.
        $themes = $this->get_list_of_themes();
        foreach ($themes as $theme) {
            $selectorclass = self::get_behat_theme_selector_override_classname($theme);
            if (isset($allcontexts[$selectorclass])) {
                unset($allcontexts[$selectorclass]);
            }
        }

        // Comments use black color, so failure path is not visible. Using color other then black/white is safer.
        // https://github.com/Behat/Behat/pull/628.
        $config = array(
            'default' => array(
                'formatters' => array(
                    'moodle_progress' => array(
                        'output_styles' => array(
                            'comment' => array('magenta'))
                    )
                ),
                'suites' => $suites,
                'extensions' => array(
                    'Behat\MinkExtension' => array(
                        'base_url' => $CFG->behat_wwwroot,
                        'goutte' => null,
                        'selenium2' => $selenium2wdhost
                    ),
                    'Moodle\BehatExtension' => array(
                        'moodledirroot' => $CFG->dirroot,
                        'steps_definitions' => $allcontexts,
                    )
                )
            )
        );

        return $config;
    }

    /**
     * Divide features between the runs and return list.
     *
     * @param array $features list of features to be divided.
     * @param int $parallelruns how many parallel runs feature needs to be divided.
     * @param int $currentrun current run for which features should be returned.
     * @return array
     */
    protected function get_features_for_the_run($features, $parallelruns, $currentrun) {

        // If no features are passed then just return.
        if (empty($features)) {
            return $features;
        }

        $allocatedfeatures = $features;

        // If parallel run, then only divide features.
        if (!empty($currentrun) && !empty($parallelruns)) {
            // Attempt to split into weighted buckets using timing information, if available.
            if ($alloc = $this->profile_guided_allocate($features, max(1, $parallelruns), $currentrun)) {
                $allocatedfeatures = $alloc;
            } else {
                // Divide the list of feature files amongst the parallel runners.
                // Pull out the features for just this worker.
                if (count($features)) {
                    $features = array_chunk($features, ceil(count($features) / max(1, $parallelruns)));

                    // Check if there is any feature file for this process.
                    if (!empty($features[$currentrun - 1])) {
                        $allocatedfeatures = $features[$currentrun - 1];
                    } else {
                        $allocatedfeatures = array();
                    }
                }
            }
        }

        return $allocatedfeatures;
    }

    /**
     * Parse $CFG->behat_profile and return the array with required config structure for behat.yml.
     *
     * $CFG->behat_profiles = array(
     *     'profile' = array(
     *         'browser' => 'firefox',
     *         'tags' => '@javascript',
     *         'wd_host' => 'http://127.0.0.1:4444/wd/hub',
     *         'capabilities' => array(
     *             'platform' => 'Linux',
     *             'version' => 44
     *         )
     *     )
     * );
     *
     * @param string $profile profile name
     * @param array $values values for profile.
     * @return array
     */
    protected function get_behat_profile($profile, $values) {
        // Values should be an array.
        if (!is_array($values)) {
            return array();
        }

        // Check suite values.
        $behatprofilesuites = array();
        // Fill tags information.
        if (isset($values['tags'])) {
            $behatprofilesuites = array(
                'suites' => array(
                    'default' => array(
                        'filters' => array(
                            'tags' => $values['tags'],
                        )
                    )
                )
            );
        }

        // Selenium2 config values.
        $behatprofileextension = array();
        $seleniumconfig = array();
        if (isset($values['browser'])) {
            $seleniumconfig['browser'] = $values['browser'];
        }
        if (isset($values['wd_host'])) {
            $seleniumconfig['wd_host'] = $values['wd_host'];
        }
        if (isset($values['capabilities'])) {
            $seleniumconfig['capabilities'] = $values['capabilities'];
        }
        if (!empty($seleniumconfig)) {
            $behatprofileextension = array(
                'extensions' => array(
                    'Behat\MinkExtension' => array(
                        'selenium2' => $seleniumconfig,
                    )
                )
            );
        }

        return array($profile => array_merge($behatprofilesuites, $behatprofileextension));
    }

    /**
     * Attempt to split feature list into fairish buckets using timing information, if available.
     * Simply add each one to lightest buckets until all files allocated.
     * PGA = Profile Guided Allocation. I made it up just now.
     * CAUTION: workers must agree on allocation, do not be random anywhere!
     *
     * @param array $features Behat feature files array
     * @param int $nbuckets Number of buckets to divide into
     * @param int $instance Index number of this instance
     * @return array|bool Feature files array, sorted into allocations
     */
    public function profile_guided_allocate($features, $nbuckets, $instance) {

        $behattimingfile = defined('BEHAT_FEATURE_TIMING_FILE') &&
        @filesize(BEHAT_FEATURE_TIMING_FILE) ? BEHAT_FEATURE_TIMING_FILE : false;

        if (!$behattimingfile || !$behattimingdata = @json_decode(file_get_contents($behattimingfile), true)) {
            // No data available, fall back to relying on steps data.
            $stepfile = "";
            if (defined('BEHAT_FEATURE_STEP_FILE') && BEHAT_FEATURE_STEP_FILE) {
                $stepfile = BEHAT_FEATURE_STEP_FILE;
            }
            // We should never get this. But in case we can't do this then fall back on simple splitting.
            if (empty($stepfile) || !$behattimingdata = @json_decode(file_get_contents($stepfile), true)) {
                return false;
            }
        }

        arsort($behattimingdata); // Ensure most expensive is first.

        $realroot = realpath(__DIR__.'/../../../').'/';
        $defaultweight = array_sum($behattimingdata) / count($behattimingdata);
        $weights = array_fill(0, $nbuckets, 0);
        $buckets = array_fill(0, $nbuckets, array());
        $totalweight = 0;

        // Re-key the features list to match timing data.
        foreach ($features as $k => $file) {
            $key = str_replace($realroot, '', $file);
            $features[$key] = $file;
            unset($features[$k]);
            if (!isset($behattimingdata[$key])) {
                $behattimingdata[$key] = $defaultweight;
            }
        }

        // Sort features by known weights; largest ones should be allocated first.
        $behattimingorder = array();
        foreach ($features as $key => $file) {
            $behattimingorder[$key] = $behattimingdata[$key];
        }
        arsort($behattimingorder);

        // Finally, add each feature one by one to the lightest bucket.
        foreach ($behattimingorder as $key => $weight) {
            $file = $features[$key];
            $lightbucket = array_search(min($weights), $weights);
            $weights[$lightbucket] += $weight;
            $buckets[$lightbucket][] = $file;
            $totalweight += $weight;
        }

        if ($totalweight && !defined('BEHAT_DISABLE_HISTOGRAM') && $instance == $nbuckets && !defined('PHPUNIT_TEST')) {
            echo "Bucket weightings:\n";
            foreach ($weights as $k => $weight) {
                echo $k + 1 . ": " . str_repeat('*', 70 * $nbuckets * $weight / $totalweight) . PHP_EOL;
            }
        }

        // Return the features for this worker.
        return $buckets[$instance - 1];
    }

    /**
     * Overrides default config with local config values
     *
     * array_merge does not merge completely the array's values
     *
     * @param mixed $config The node of the default config
     * @param mixed $localconfig The node of the local config
     * @return mixed The merge result
     */
    public function merge_config($config, $localconfig) {

        if (!is_array($config) && !is_array($localconfig)) {
            return $localconfig;
        }

        // Local overrides also deeper default values.
        if (is_array($config) && !is_array($localconfig)) {
            return $localconfig;
        }

        foreach ($localconfig as $key => $value) {

            // If defaults are not as deep as local values let locals override.
            if (!is_array($config)) {
                unset($config);
            }

            // Add the param if it doesn't exists or merge branches.
            if (empty($config[$key])) {
                $config[$key] = $value;
            } else {
                $config[$key] = $this->merge_config($config[$key], $localconfig[$key]);
            }
        }

        return $config;
    }

    /**
     * Merges $CFG->behat_config with the one passed.
     *
     * @param array $config existing config.
     * @return array merged config with $CFG->behat_config
     */
    public function merge_behat_config($config) {
        global $CFG;

        // In case user defined overrides respect them over our default ones.
        if (!empty($CFG->behat_config)) {
            foreach ($CFG->behat_config as $profile => $values) {
                $config = $this->merge_config($config, $this->get_behat_config_for_profile($profile, $values));
            }
        }

        return $config;
    }

    /**
     * Parse $CFG->behat_config and return the array with required config structure for behat.yml
     *
     * @param string $profile profile name
     * @param array $values values for profile
     * @return array
     */
    public function get_behat_config_for_profile($profile, $values) {
        // Only add profile which are compatible with Behat 3.x
        // Just check if any of Bheat 2.5 config is set. Not checking for 3.x as it might have some other configs
        // Like : rerun_cache etc.
        if (!isset($values['filters']['tags']) && !isset($values['extensions']['Behat\MinkExtension\Extension'])) {
            return array($profile => $values);
        }

        // Parse 2.5 format and get related values.
        $oldconfigvalues = array();
        if (isset($values['extensions']['Behat\MinkExtension\Extension'])) {
            $extensionvalues = $values['extensions']['Behat\MinkExtension\Extension'];
            if (isset($extensionvalues['selenium2']['browser'])) {
                $oldconfigvalues['browser'] = $extensionvalues['selenium2']['browser'];
            }
            if (isset($extensionvalues['selenium2']['wd_host'])) {
                $oldconfigvalues['wd_host'] = $extensionvalues['selenium2']['wd_host'];
            }
            if (isset($extensionvalues['capabilities'])) {
                $oldconfigvalues['capabilities'] = $extensionvalues['capabilities'];
            }
        }

        if (isset($values['filters']['tags'])) {
            $oldconfigvalues['tags'] = $values['filters']['tags'];
        }

        if (!empty($oldconfigvalues)) {
            behat_config_manager::$autoprofileconversion = true;
            return $this->get_behat_profile($profile, $oldconfigvalues);
        }

        // If nothing set above then return empty array.
        return array();
    }

    /**
     * Merges $CFG->behat_profiles with the one passed.
     *
     * @param array $config existing config.
     * @return array merged config with $CFG->behat_profiles
     */
    public function merge_behat_profiles($config) {
        global $CFG;

        // Check for Moodle custom ones.
        if (!empty($CFG->behat_profiles) && is_array($CFG->behat_profiles)) {
            foreach ($CFG->behat_profiles as $profile => $values) {
                $config = $this->merge_config($config, $this->get_behat_profile($profile, $values));
            }
        }

        return $config;
    }

    /**
     * Cleans the path returned by get_components_with_tests() to standarize it
     *
     * @see tests_finder::get_all_directories_with_tests() it returns the path including /tests/
     * @param string $path
     * @return string The string without the last /tests part
     */
    public final function clean_path($path) {

        $path = rtrim($path, DIRECTORY_SEPARATOR);

        $parttoremove = DIRECTORY_SEPARATOR . 'tests';

        $substr = substr($path, strlen($path) - strlen($parttoremove));
        if ($substr == $parttoremove) {
            $path = substr($path, 0, strlen($path) - strlen($parttoremove));
        }

        return rtrim($path, DIRECTORY_SEPARATOR);
    }

    /**
     * The relative path where components stores their behat tests
     *
     * @return string
     */
    public static final function get_behat_tests_path() {
        return DIRECTORY_SEPARATOR . 'tests' . DIRECTORY_SEPARATOR . 'behat';
    }

    /**
     * Return context name of behat_theme selector to use.
     *
     * @param string $themename name of the theme.
     * @param bool $includeclass if class should be included.
     * @return string
     */
    public static final function get_behat_theme_selector_override_classname($themename, $includeclass = false) {
        global $CFG;

        $overridebehatclassname = 'behat_theme_'.$themename.'_behat_selectors';

        if ($includeclass) {
            $themeoverrideselector = $CFG->dirroot . DIRECTORY_SEPARATOR . 'theme' . DIRECTORY_SEPARATOR . $themename .
                self::get_behat_tests_path() . DIRECTORY_SEPARATOR . $overridebehatclassname . '.php';

            if (file_exists($themeoverrideselector)) {
                require_once($themeoverrideselector);
            }
        }

        return $overridebehatclassname;
    }

    /**
     * List of components which contain behat context or features.
     *
     * @return array
     */
    private function get_components_with_tests() {
        if (empty($this->componentswithtests)) {
            $this->componentswithtests = tests_finder::get_components_with_tests('behat');
        }

        return $this->componentswithtests;
    }

    /**
     * Remove list of blacklisted features from the feature list.
     *
     * @param array $features list of original features.
     * @param array|string $blacklist list of features which needs to be removed.
     * @return array features - blacklisted features.
     */
    protected function remove_blacklisted_features_from_list($features, $blacklist) {

        // If no blacklist passed then return.
        if (empty($blacklist)) {
            return $features;
        }

        // If there is no feature in suite then just return what was passed.
        if (empty($features)) {
            return $features;
        }

        if (!is_array($blacklist)) {
            $blacklist = array($blacklist);
        }

        // Remove blacklisted features.
        foreach ($blacklist as $blacklistpath) {

            list($key, $featurepath) = $this->get_clean_feature_key_and_path($blacklistpath);

            if (isset($features[$key])) {
                $features[$key] = null;
                unset($features[$key]);
            } else if (empty($this->tags)) {
                // If tags not set, then ensure we have a blacklisted feature in core. Else, let user know that
                // blacklisted feature is invalid.
                $featurestocheck = $this->get_components_features();
                if (!isset($featurestocheck[$key]) && !defined('PHPUNIT_TEST')) {
                    behat_error(BEHAT_EXITCODE_REQUIREMENT, 'Blacklisted feature "' . $blacklistpath . '" not found.');
                }
            }
        }

        return $features;
    }

    /**
     * Return list of behat suites. Multiple suites are returned if theme
     * overrides default step definitions/features.
     *
     * @param int $parallelruns number of parallel runs
     * @param int $currentrun current run.
     * @return array list of suites.
     */
    protected function get_behat_suites($parallelruns = 0, $currentrun = 0) {
        $features = $this->get_components_features();
        $contexts = $this->get_components_contexts();

        // Get number of parallel runs and current run.
        if (!empty($parallelruns) && !empty($currentrun)) {
            $this->set_parallel_run($parallelruns, $currentrun);
        } else {
            $parallelruns = $this->get_number_of_parallel_run();
            $currentrun = $this->get_current_run();;
        }

        $blacklistedfeatures = array();
        $themefeatures = array();
        $themesuitecontexts = array();
        $themecontexts = array();

        $themes = $this->get_list_of_themes();

        // Create list of theme suite features and contexts.
        foreach ($themes as $theme) {
            // Get theme features.
            list($blacklistedfeatures[$theme], $themefeatures[$theme]) = $this->get_behat_features_for_theme($theme);

            list($themecontexts[$theme], $themesuitecontexts[$theme]) = $this->get_behat_contexts_for_theme($theme);
        }

        // Remove list of theme features for default suite, as default suite should not run theme specific features.
        foreach ($themefeatures as $removethemefeatures) {
            $features = $this->remove_blacklisted_features_from_list($features, $removethemefeatures);
        }

        // Remove list of theme features for default suite, as default suite should not run theme specific features.
        foreach ($themecontexts as $theme => $themeblacklistcontexts) {
            if ($themeblacklistcontexts) {
                foreach ($themeblacklistcontexts as $c) {
                    // Remove theme specific contexts from default contexts.
                    unset($contexts[$c]);

                    // Remove theme specific contexts from other themes.
                    foreach ($themes as $currenttheme) {
                        if (($currenttheme != $theme) && isset($themesuitecontexts[$currenttheme][$c])) {
                            unset($themesuitecontexts[$currenttheme][$c]);
                        }
                    }
                }
            }
        }

        // Return sub-set of features if parallel run.
        $featuresforrun = $this->get_features_for_the_run($features, $parallelruns, $currentrun);

        // Default suite.
        $suites = array(
            'default' => array(
                'paths' => array_values($featuresforrun),
                'contexts' => array_keys($contexts),
            )
        );

        // Set suite for each theme.
        foreach ($themes as $theme) {
            // Get list of features which will be included in theme.
            // If theme suite with all features is set, then we want all core features to be part of theme suite.
            if ($this->themesuitewithallfeatures) {
                // If there is no theme specific feature. Then it's just core features.
                if (empty($themefeatures[$theme])) {
                    $themesuitefeatures = $features;
                } else {
                    $themesuitefeatures = array_merge($features, $themefeatures[$theme]);
                }
            } else {
                $themesuitefeatures = $themefeatures[$theme];
            }

            // Remove blacklisted features.
            $themesuitefeatures = $this->remove_blacklisted_features_from_list($themesuitefeatures, $blacklistedfeatures[$theme]);

            // Return sub-set of features if parallel run.
            $themesuitefeatures = $this->get_features_for_the_run($themesuitefeatures, $parallelruns, $currentrun);

            // Add suite no matter what. If there is no feature in suite then it will just exist successfully with no
            // scenarios. But if we don't set this then the user has to know which run doesn't have suite and which run do.
            $suites = array_merge($suites, array(
                $theme => array(
                    'paths'    => array_values($themesuitefeatures),
                    'contexts' => array_keys($themesuitecontexts[$theme]),
                )
            ));
        }

        return $suites;
    }

    /**
     * Return list of themes which can be set in moodle.
     *
     * @return array list of themes with tests.
     */
    protected function get_list_of_themes() {
        $selectablethemes = array();

        // Get all themes installed on site.
        $themes = core_component::get_plugin_list('theme');
        ksort($themes);

        foreach ($themes as $themename => $themedir) {
            // Load the theme config.
            try {
                $theme = theme_config::load($themename);
            } catch (Exception $e) {
                // Bad theme, just skip it for now.
                continue;
            }
            if ($themename !== $theme->name) {
                // Obsoleted or broken theme, just skip for now.
                continue;
            }
            if ($theme->hidefromselector) {
                // The theme doesn't want to be shown in the theme selector and as theme
                // designer mode is switched off we will respect that decision.
                continue;
            }
            if ($themename == theme_config::DEFAULT_THEME) {
                // Don't include default theme, as default suite will be running with this theme.
                continue;
            }
            $selectablethemes[] = $themename;
        }

        return $selectablethemes;
    }

    /**
     * Returns all the directories having overridden tests.
     *
     * @param string $theme name of theme
     * @param string $testtype The kind of test we are looking for
     * @return array all directories having tests
     */
    protected function get_test_directories_overridden_for_theme($theme, $testtype) {
        global $CFG;

        $testtypes = array(
            'contexts' => '|behat_.*\.php$|',
            'features' => '|.*\.feature$|',
        );
        $themetestdir = "/theme/" . $theme . '/tests/behat';
        $themetestdirfullpath = $CFG->dirroot . $themetestdir;

        // If test directory doesn't exist then return.
        if (!is_dir($themetestdirfullpath)) {
            return array();
        }

        $directoriestosearch = glob($themetestdirfullpath . DIRECTORY_SEPARATOR . '*' , GLOB_ONLYDIR);

        // Include theme directory to find tests.
        $dirs[realpath($themetestdirfullpath)] = trim(str_replace('/', '_', $themetestdir), '_');

        // Search for tests in valid directories.
        foreach ($directoriestosearch as $dir) {
            $dirite = new RecursiveDirectoryIterator($dir);
            $iteite = new RecursiveIteratorIterator($dirite);
            $regexp = $testtypes[$testtype];
            $regite = new RegexIterator($iteite, $regexp);
            foreach ($regite as $path => $element) {
                $key = dirname($path);
                $value = trim(str_replace(DIRECTORY_SEPARATOR, '_', str_replace($CFG->dirroot, '', $key)), '_');
                $dirs[$key] = $value;
            }
        }
        ksort($dirs);

        return array_flip($dirs);
    }

    /**
     * Return blacklisted contexts or features for a theme, as defined in blacklist.json.
     *
     * @param string $theme themename
     * @param string $testtype test type (contexts|features)
     * @return array list of blacklisted contexts or features
     */
    protected function get_blacklisted_tests_for_theme($theme, $testtype) {
        global $CFG;

        $themetestpath = $CFG->dirroot . DIRECTORY_SEPARATOR . "theme" . DIRECTORY_SEPARATOR . $theme .
            self::get_behat_tests_path();

        if (file_exists($themetestpath . DIRECTORY_SEPARATOR . 'blacklist.json')) {
            // Blacklist file exist. Leave it for last to clear the feature and contexts.
            $blacklisttests = @json_decode(file_get_contents($themetestpath . DIRECTORY_SEPARATOR . 'blacklist.json'), true);
            if (empty($blacklisttests)) {
                behat_error(BEHAT_EXITCODE_REQUIREMENT, $themetestpath . DIRECTORY_SEPARATOR . 'blacklist.json is empty');
            }

            // If features or contexts not defined then no problem.
            if (!isset($blacklisttests[$testtype])) {
                $blacklisttests[$testtype] = array();
            }
            return $blacklisttests[$testtype];
        }

        return array();
    }

    /**
     * Return list of features and step definitions in theme.
     *
     * @param string $theme theme name
     * @param string $testtype test type, either features or contexts
     * @return array list of contexts $contexts or $features
     */
    protected function get_tests_for_theme($theme, $testtype) {

        $tests = array();
        $testtypes = array(
            'contexts' => '|behat_.*\.php$|',
            'features' => '|.*\.feature$|',
        );

        // Get all the directories having overridden tests.
        $directories = $this->get_test_directories_overridden_for_theme($theme, $testtype);

        // Get overridden test contexts.
        foreach ($directories as $dirpath) {
            // All behat_*.php inside overridden directory.
            $diriterator = new DirectoryIterator($dirpath);
            $regite = new RegexIterator($diriterator, $testtypes[$testtype]);

            // All behat_*.php inside behat_config_manager::get_behat_tests_path() are added as steps definitions files.
            foreach ($regite as $file) {
                $key = $file->getBasename('.php');
                $tests[$key] = $file->getPathname();
            }
        }

        return $tests;
    }

    /**
     * Return list of blacklisted behat features for theme and features defined by theme only.
     *
     * @param string $theme theme name.
     * @return array ($themeblacklistfeatures, $themefeatures)
     */
    protected function get_behat_features_for_theme($theme) {

        // Get list of features defined by theme.
        $themefeatures = $this->get_tests_for_theme($theme, 'features');
        $themeblacklistfeatures = $this->get_blacklisted_tests_for_theme($theme, 'features');

        // If tags are specified then we just want features with specified tags.
        if (!empty($this->tags)) {
            if (!empty($themefeatures)) {
                $themefeatures = $this->filtered_features_with_tags($themefeatures);
            }
        }

        return array($themeblacklistfeatures, $themefeatures);
    }

    /**
     * Return list of contexts overridden by themes.
     *
     * @return array.
     */
    protected function get_overridden_theme_contexts() {
        if (empty($this->overriddenthemescontexts)) {
            $this->overriddenthemescontexts = array();
        }

        return $this->overriddenthemescontexts;
    }

    /**
     * Return list of behat contexts for theme and update $this->stepdefinitions list.
     *
     * @param string $theme theme name.
     * @return array list($themecontexts, $themesuitecontexts)
     */
    protected function get_behat_contexts_for_theme($theme) {

        // If we already have this list then just return. This will not change by run.
        if (!empty($this->themecontexts[$theme])) {
            return $this->themecontexts[$theme];
        }

        if (empty($this->overriddenthemescontexts)) {
            $this->overriddenthemescontexts = array();
        }

        $contexts = $this->get_components_contexts();

        // Create list of contexts used by theme suite.
        $themecontexts = $this->get_tests_for_theme($theme, 'contexts');
        $blacklistedcontexts = $this->get_blacklisted_tests_for_theme($theme, 'contexts');

        // Theme suite will use all core contexts, except the one overridden by theme.
        $themesuitecontexts = $contexts;

        foreach ($themecontexts as $context => $path) {

            // If a context in theme starts with behat_theme_{themename}_behat_* then it's overriding core context.
            if (preg_match('/^behat_theme_'.$theme.'_(\w+)$/', $context, $match)) {

                if (!empty($themesuitecontexts[$match[1]])) {
                    unset($themesuitecontexts[$match[1]]);
                }

                // Add this to the list of overridden paths, so it can be added to final contexts list for class resolver.
                $this->overriddenthemescontexts[$context] = $path;
            }

            // Don't include behat_selectors.
            if ($context === self::get_behat_theme_selector_override_classname($theme)) {
                unset($this->contexts[$context]);
                unset($themesuitecontexts[$context]);
                continue;
            }

            // Add theme specific contexts with suffix to steps definitions.
            $themesuitecontexts[$context] = $path;
        }

        // Remove blacklisted contexts.
        foreach ($blacklistedcontexts as $blacklistpath) {
            $blacklistcontext = basename($blacklistpath, '.php');

            unset($themesuitecontexts[$blacklistcontext]);
        }

        // We are only interested in the class name of context.
        $this->themecontexts[$theme] = $themesuitecontexts;

        return array(array_keys($themecontexts), $themesuitecontexts);
    }
}