Deprecate DiffEngine and replace with sebastian/diff

The Needs Review Queue Bot → tested this issue. It either no longer applies to Drupal core, or fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

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Rebased.

Unhappy PHPStan :/

The proposed approach looks pretty neat while keeping us within the constraints of the interface to the existing Diff component.

Adding some tags for things that we still need; we also should add an explicit dependency on sebastian/diff to the core composer.json and also the component's composer.json.

Added a draft CR and reflected in the deprecation messages, fixed PHPStan errors.

Updated IS and issue title

drupal:10.0.0 needs update to 10.1.0

A comment that I think can be removed now, plus we also need to add the dependency to core/lib/Drupal/Component/Diff/composer.json.

Thanks for the review @longwave, commented inline.

Removed change record as one was added.

This was a near perfect think I think. Issue summary was clear with problem, steps, and tasks.

Reviewing the PR everything looks good, not sure what more can be looked at.

The change record is only a placeholder and has no detail, also we need a dependency evaluation.

Fleshed out the CR.

Added dependency evaluation

Rebased.

This looks good to me, we might want to look at the Diff component itself later, but no need to do that to make the switch here and the bc layer is tidy.

Since I opened this, probably better if another committer commits it, or at least will give it a few days if no-one else does.

Committed and pushed ce28a42738 to 10.1.x. Thanks!

mondrake → closed merge request !2543

Published the CR

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

Unfortunately this change has resulted in a regression in the update_helper module (and also the config_update module) see 🐛 DiffOpOutputBuilder does not correctly match the 10.0.x implementation and produces unexpected output Fixed .

Turns out we need one more fix for update_helper... 🐛 DiffOpOutputBuilder does not correctly match the 10.0.x implementation and produces unexpected output (part 2) Needs review

This has also introduced a regression in the diff contrib module when content in revisions have different line endings.

🐛 Old content with different line endings can break diff entirely Active