VersionPress\VersionPress::isActive PHP Method

    public static function isActive()
    {
        return defined('VERSIONPRESS_ACTIVATION_FILE') && file_exists(VERSIONPRESS_ACTIVATION_FILE);
    }

 /**
  * Commits all changes made by Composer.
  *
  * @subcommand commit-composer-changes
  */
 public function commitComposerChanges($args, $assoc_args)
 {
     if (!VersionPress::isActive()) {
         WP_CLI::error('VersionPress is not active. Changes will be not committed.');
     }
     $pluginsAndThemesBeforeUpdate = get_transient($this->pluginsThemesTransient);
     delete_transient($this->pluginsThemesTransient);
     $currentPluginsAndThemes = $this->getPackages();
     $plugins = array_merge($pluginsAndThemesBeforeUpdate['plugins'], $currentPluginsAndThemes['plugins']);
     $themes = array_merge($pluginsAndThemesBeforeUpdate['themes'], $currentPluginsAndThemes['themes']);
     $changes = $this->detectChanges();
     $installedPackages = $changes['installed'];
     $removedPackages = $changes['removed'];
     $updatedPackages = $changes['updated'];
     $this->forceRelatedActions('install', $installedPackages, $plugins, $themes);
     $this->forceRelatedActions('delete', $removedPackages, $plugins, $themes);
     $this->forceRelatedActions('update', $updatedPackages, $plugins, $themes);
 }