Problem/Motivation

According to theme.api.php, this is the signature of hook_theme_suggestions_alter() and hook_theme_suggestions_HOOK_alter():

function hook_theme_suggestions_alter(array &$suggestions, array $variables, $hook)

Note that $variables is NOT passed by reference.

However, in ThemeManager::render(), we see something different:

    // Invoke hook_theme_suggestions_alter() and
    // hook_theme_suggestions_HOOK_alter().
    $hooks = [
      'theme_suggestions',
      'theme_suggestions_' . $base_theme_hook,
    ];
    $this->moduleHandler->alter($hooks, $suggestions, $variables, $base_theme_hook);
    $this->alter($hooks, $suggestions, $variables, $base_theme_hook);

Those alter() calls are passing $variables by reference.

Steps to reproduce

N/A

Proposed resolution

Make sure the documented function signatures are accurate, and explicitly state that $variables is passed by reference.

Remaining tasks

Fix it.

User interface changes

None.

API changes

Nope, but better documentation!

Data model changes

None.

Release notes snippet

TBD, likely none.

Comments

phenaproxima created an issue. See original summary.

Version: 9.2.x-dev » 9.3.x-dev

Drupal 9.2.0-alpha1 will be released the week of May 3, 2021, which means new developments and disruptive changes should now be targeted for the 9.3.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.3.x-dev » 9.4.x-dev

Drupal 9.3.0-rc1 was released on November 26, 2021, which means new developments and disruptive changes should now be targeted for the 9.4.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.4.x-dev » 9.5.x-dev

Drupal 9.4.0-alpha1 was released on May 6, 2022, which means new developments and disruptive changes should now be targeted for the 9.5.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.5.x-dev » 10.1.x-dev

Drupal 9.5.0-beta2 and Drupal 10.0.0-beta2 were released on September 29, 2022, which means new developments and disruptive changes should now be targeted for the 10.1.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 10.1.x-dev » 11.x-dev

Drupal core is moving towards using a “main” branch. As an interim step, a new 11.x branch has been opened, as Drupal.org infrastructure cannot currently fully support a branch named main. New developments and disruptive changes should now be targeted for the 11.x branch, which currently accepts only minor-version allowed changes. For more information, see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 11.x-dev » main

Drupal core is now using the main branch as the primary development branch. New developments and disruptive changes should now be targeted to the main branch.

Read more in the announcement.

quietone’s picture

quietone commented
Status: Active » Closed (outdated)

This was fixed in #3409982: [D10.2 regression] Theme suggestions cannot alter variables anymore

I am closing this as outdated.

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