Notify about double serialization. - 62483

[apermo]

Added _doing_it_wrong() to maybe_serialize to notify about double serialization.

Trac ticket: https://core.trac.wordpress.org/ticket/62483#ticket

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[audrasjb]

@apermo PHP Unit Tests are failing, this changeset will require some test case update.

[apermo]

@audrasjb I'll try to figure out how to fix them. In case I need help I'll reach out.

[apermo]

@audrasjb

The actual error message generated is:

Double serialization detected, serialized data is likely sent to update_option(), add_option(), update_*_meta(), add_*_meta() and similar functions. These functions will automatically serialize if needed. (This message was added in version 3.6.1.)

I assumed that the third parameter of _doing_it_wrong() expected the WP version, where the behavior was added, but reading the message, this looks like it should be the version where the message is added, so possibly 6.8?

Your thought?

[apermo]

@audrasjb That recent push should fix all but one test error, and I'm unsure how to handle that one.

That is thrown in tests/phpunit/tests/privacy/wpPrivacyGeneratePersonalDataExportFile.php test_doing_it_wrong_for_export_data_grouped_invalid_type()

The Data provider will return value that will trigger the double serialization.

wordpress-develop/tests/phpunit/tests/privacy/wpPrivacyGeneratePersonalDataExportFile.php

Line 237 in 12eaef1

array( serialize( array( 10, 'WordPress', null, true, false ) ) ),

My best guess would be to remove that single line, that did fix the remaining error locally.

It was added by @SergeyBiryukov in https://core.trac.wordpress.org/changeset/50613

Happy to discuss this, maybe Sergey can provide an idea.

[apermo]

Added a condition to the test, instead of altering the dataset, so the test is not weakened.