Demo content module triggers many "error" messages during install process

[budda]

Enabling the demo content module on a site with some content already added spat out a long list of warnings on the "Some required modules must be enabled" page.

Error message
Deprecated function: Return type of RRule\RRule::current() should either be compatible with Iterator::current(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in include() (line 92 of /var/www/html/vendor/rlanvin/php-rrule/src/RRule.php).
include('/var/www/html/vendor/rlanvin/php-rrule/src/RRule.php') (Line: 571)
Composer\Autoload\includeFile('/var/www/html/vendor/composer/../rlanvin/php-rrule/src/RRule.php') (Line: 428)
Composer\Autoload\ClassLoader->loadClass('RRule\RRule')
class_exists('\RRule\RRule') (Line: 25)
date_recur_requirements('install')
call_user_func_array('date_recur_requirements', Array) (Line: 392)
Drupal\Core\Extension\ModuleHandler->invoke('date_recur', 'requirements', Array) (Line: 1032)
drupal_check_module('date_recur') (Line: 437)
Drupal\system\Form\ModulesListForm->buildModuleList(Object) (Line: 455)
Drupal\system\Form\ModulesListForm->submitForm(Array, Object)
call_user_func_array(Array, Array) (Line: 114)
Drupal\Core\Form\FormSubmitter->executeSubmitHandlers(Array, Object) (Line: 52)
Drupal\Core\Form\FormSubmitter->doSubmitForm(Array, Object) (Line: 592)
Drupal\Core\Form\FormBuilder->processForm('system_modules', Array, Object) (Line: 320)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object) (Line: 73)
Drupal\Core\Controller\FormController->getContentResult(Object, Object)
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 564)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 158)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 80)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 708)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)
Deprecated function: Return type of RRule\RRule::next() should either be compatible with Iterator::next(): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in include() (line 92 of /var/www/html/vendor/rlanvin/php-rrule/src/RRule.php).
include('/var/www/html/vendor/rlanvin/php-rrule/src/RRule.php') (Line: 571)
Composer\Autoload\includeFile('/var/www/html/vendor/composer/../rlanvin/php-rrule/src/RRule.php') (Line: 428)
Composer\Autoload\ClassLoader->loadClass('RRule\RRule')
class_exists('\RRule\RRule') (Line: 25)
date_recur_requirements('install')
call_user_func_array('date_recur_requirements', Array) (Line: 392)
Drupal\Core\Extension\ModuleHandler->invoke('date_recur', 'requirements', Array) (Line: 1032)
drupal_check_module('date_recur') (Line: 437)
Drupal\system\Form\ModulesListForm->buildModuleList(Object) (Line: 455)
Drupal\system\Form\ModulesListForm->submitForm(Array, Object)
call_user_func_array(Array, Array) (Line: 114)
Drupal\Core\Form\FormSubmitter->executeSubmitHandlers(Array, Object) (Line: 52)
Drupal\Core\Form\FormSubmitter->doSubmitForm(Array, Object) (Line: 592)
Drupal\Core\Form\FormBuilder->processForm('system_modules', Array, Object) (Line: 320)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object) (Line: 73)
Drupal\Core\Controller\FormController->getContentResult(Object, Object)
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 564)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 158)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 80)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 708)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)

After agreeing to install the dependencies nothing seemed to happen with demo content. Re-visiting the module list showed the module was still not enabled. Repeating the process a second time did not generate any of the above warnings.

All the dependency modules appear to have been enabled okay. Again, re-visiting the module list showed the module was still not enabled. Tried 3 times with no chance to enable the demo content.

Running on PHP 8.1.0

[budda]

Moved to https://github.com/localgovdrupal/localgov_demo/issues/74