Execute filtering only when a collection is passed to the data source…

[mgarciaebo]

… of a UI Component form.

Description

There should be some check in order to perform collection actions only if the data source of UI Componet forms contents and actual valid collection, and avoiding them if not. This keeps model-collections forms working as usual, and avoids crashes on stand-alone forms.

Fixed Issues (if relevant)

1. UI Component forms not related with any model throw fatal error #13573: UI Component forms not related with any model throw fatal error

Manual testing scenarios

1. Starting from a vanilla Magento, download, install and enable your own sample Form UI Component, following the instructions given at: https://github.com/magento/magento2-samples/tree/master/sample-module-form-uicomponent
2. Go to the URL provided by the extension, which is [magento2-admin-url]/sampleform
3. You should now get the expected form:
   

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

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[ghost]

@mgarciaavz unfortunately, only members of the maintainers team are allowed to assign developers to the pull request

[mgarciaebo]

This PR is a slightly different approach for this other: #13574, which didn't end up merged due to performance degradation issues (mentioned by @rogyar here: #13574 (comment)). I found no evidence of those issues here, but if any, I guess that your testing tools will end up finding them.

[m2-assistant]

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[mgarciaebo]

Hi @melnikovi @rogyar, I stepped into an error that I can't fix (or I shouldn't, at least). The phpcs is reporting this warning:

Abstract classes MUST NOT be marked as public @api.

I have fixed some other issues related with the doc blocks in the file "app/code/Magento/Ui/DataProvider/AbstractDataProvider.php", but decision about @api related issues must be taken at a higher level, so by you I guess.

Thank you!

[rogyar]

Hi @mgarciaebo. Please, check the conflicting files. Also, according to the new definition of done all changes should be covered by automated tests. I would recommend covering this case with a unit test.

Thank you!

[joshuaswarren]

Hello, @mgarciaebo - thank you so much for your involvement in the Magento community and for your work specifically on submitting this pull request!

This request has been open for a while now, and we're coming up on 3 years of no activity after a request was made to add a unit test to cover this PR. Are you still working on the Magento platform? Are you able to spend some time to move this pull request forward?

[mgarciaebo]

Hi @joshuaswarren, thanks for reaching out.

Yes, I'm still working on Magento and will take a look at this asap. It would be really nice to finally make this PR moving forward :D