Allow patterns files to be organized in sub-folders.

[juanfra]

Trac ticket: https://core.trac.wordpress.org/ticket/62378
Gutenberg issue: WordPress/gutenberg#50144

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

Description

I'm changing the initial $dirpath to avoid having the trailing slash, as the file exist can behave differently in different file systems.

Then, I'm making use of the static method scandir to check for php files in the directory recursively. Finally, adding the trailing slash so that this str_replace leaves only the required slashes in the $pattern_data array.

Testing Instructions

1. Use a block theme.
2. Add a pattern in your theme, for example, /patterns/subfolder/my-pattern.php
3. Open a post or page.
4. Confirm that 'my-pattern' shows up

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Props juanfra, poena.

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[github-actions]

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[carolinan]

I followed the testing instructions and the update works well for me.
In addition, I moved some existing patterns to different nested subfolders, without issues.

• Templates or other patterns that includes the patterns that were moved still works
• The patterns are listed in the inserter
• The patterns are listed in the pattern DataViews
• The patterns can be duplicated from the pattern DataViews

[bgardner]

I would love to see this PR get merged!

[bgardner]

Any updates here? This seems to be a lightweight feature to be added, one that theme developers would love.

[carolinan]

@bgardner All the reviews and commits etc are public, if you don't see any updates then there are none :)