WordPress’ core code block does not wrap text. This is ok most of the time but sometimes it’s nice for long lines to wrap. We could set white space to pre-wrap
on .wp-block-code > code
but this will affect all code blocks. Let’s create a code block style so we can toggle text wrapping only when we need it.
First create a JavaScript file and register the wrap block style on the core/code block.
wp.domReady(() => {
wp.blocks.registerBlockStyle('core/code', {
name: 'wrap',
label: 'Wrap',
});
});
The “name” will get appended to is-style
creating the class .is-style-wrap
which is added to the code block when the style is selected in the block sidebar.
<pre class="wp-block-code is-style-wrap">
<code>...</code>
</pre>
Next enqueue the JavaScript in your theme’s functions.php
using the enqueue_block_editor_assets
hook. You can enqueue it individually or built with the rest of your editor JavaScript.
You should now see the style in the block sidebar when a code block is selected. The “Default” style will remove classes added by this or any other block styles.
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Finally write and enqueue the CSS that will actually make the text wrap. We need !important
to override WordPress core’s rule which also uses !important
.
.wp-block-code {
&.is-style-wrap {
code {
white-space: pre-wrap !important;
}
}
}
See the official Block Styles API Reference documentation for more.