Update documentation for table.html.twig around table cells

I have done some debugging and determined what is happening.

The Twig template states:

tag: The HTML tag name to use; either 'th' or 'td'.

From within the context of the Twig template, this is correct. However, the template does not document how to set this variable.

In theme, inc. I can see that the tag type is set here: https://git.drupalcode.org/project/drupal/-/blob/11.x/core/includes/them...
With the $is_header value being set here: https://git.drupalcode.org/project/drupal/-/blob/11.x/core/includes/them...

So, to set a table cell to use a TH tag, the header attribute for the cell must be set. Here is a simple example:

$table = [
  '#theme' => 'table',
  '#rows' => [
    [
      [
        'data' => 'Header cell',
        // Setting header to TRUE will cause this cell
        // to be a <th/> rather than the default <td/>.
        'header' => TRUE,
      ],
      [
        'data' => 'Normal cell',
      ],
    ],
  ],
];

Maybe an update to the table.html.twig documentation to indicate how to set a table cell as a header, would be beneficial to developers.

Utkarsh_33 → changed the visibility of the branch 3437166-rendering-engine-disregards to hidden.

Updated the docs stating the use of header flag to identify whether a cell can be used a

Updated the title to more lineup with the solution but seems straight forward.

The updated documentation listed the header attribute as a child of a header cell, but it is not. It is a sibling to data</data>. Also, there are multiple instances of <code>table.html.twig in core, and each instance needs to be updated.

Can the MR be updated to point to 11.x vs 11.0.x

'header' is an key of the 'cells' array, so I think the documentation should set it as a child of that array.

Feedback appears to be addressed. Thanks @Utkarsh_33 for updating that target

Can someone update the comment so that it wraps at 80 chars? after that it's good to go.

Wrapped to 80

nod_ → closed merge request !8049

Committed and pushed 8778ac1801 to 11.x and 8a300d4337 to 11.0.x and 34abc72b52 to 10.4.x and 3923915994 to 10.3.x. Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.