Creates add_attribute twig function

[waako]

Replicates the Drupal twig function create_attribute for patternlab https://www.drupal.org/docs/8/theming/twig/functions-in-twig-templates#create_attribute

#8 got me thinking about this, so used existing link twig function to make create_attribute work in Pattern Lab. Tested locally with:

<p{{ create_attribute({'class': ['paragraph', 'text']}) }}>{{ content }}</p>

which results in generated html:

<p class="paragraph text">Test paragraph content</p>

[waako]

Needs improving to work with any attribute though

[waako]

Function now loops through all the attributes

[piouPiouM]

Hi @waako,

I used the following to rely on Drupal's tools:

<?php
/**
 * @file
 * Add "create_attribute" function for Pattern Lab.
 */

use \Drupal\Core\Template\Attribute;

$function = new Twig_SimpleFunction('create_attribute', function ($attributes = []) {
  return new Attribute($attributes);
});

[sghoweri]

@piouPiouM @waako

We do something virtually identical in our design system in order to make sure all of Drupal’s attributes functionality makes it in there (including the setAttribute, addClass, and removeClass methods, etc)

https://github.com/bolt-design-system/bolt/blob/master/packages/core-php/src/TwigFunctions.php#L240

use \Drupal\Core\Template\Attribute;

//...

// Backport the native create_attribute function from Drupal to natively work in Pattern Lab
  public static function create_attribute() {
    return new Twig_SimpleFunction('create_attribute', function($attributes) {
      return is_array($attributes) ? new Attribute($attributes) : $attributes;
    });
  }

[waako]

@piouPiouM @sghoweri Thanks, that seems to make sense, did not realise that could use a Drupal class inside patternlab function.

[kristiaanvandeneynde]

Any way I can include this in my project already? The fix mentioned by sghoweri?