PHP 8.0 support

[julienfalque]

Syntax changes that require new tests to make sure the tool is compatible with PHP 8.0:

• Named Arguments
  • update existing code => integration test in Add PHP8 integration test #5399
  • new feature
• Nullsafe operator
  • update existing code => integration test in Add PHP8 integration test #5399
  • new feature
• Attributes (Attributes v2, Attribute Amendments, Shorter Attribute Syntax and Shorter Attribute Syntax Change)
  • update existing code (PHP8 - Attribute support #5284)
  • new feature
• Union Types 2.0
  • update existing code => integration test in Add PHP8 integration test #5399
  • new feature
• Allow ::class on objects
  • update existing code (PHP8 #5166)
  • new feature
• Static return type
  • update existing code (PHP8 #5177, [FinalStaticAccessFixer] Handle new static() in final class #5184)
  • new feature (PHP8 #5177, [FinalStaticAccessFixer] Handle new static() in final class #5184)
• Variable Syntax Tweaks
  • update existing code
  • new feature
• Allow trailing comma in parameter list
  • update existing code (PHP8 - Allow trailing comma in parameter list support #5240 PHP8 - Allow trailing comma in parameter list support #5239)
  • new feature
• Allow trailing comma in closure use lists
  • update existing code
  • new feature
• Mixed Type v2
  • update existing code (PHP8 - mixed type support #5254)
  • new feature
• throw expression
  • update existing code (PHP8 - throw expression support #5232)
  • new feature
• non-capturing catches
  • update existing code
  • new feature (WIP NoUnusedCapturingCatchFixer - introduction #5175)
• Constructor Property Promotion
  • update existing code (PHP8 - Constructor Property Promotion support #5277)
  • new feature
• Match expression v2
  • update existing code (PHP8 - match support #5251)
  • new feature
• Add str_starts_with() and str_ends_with() functions
  • update existing code
  • new feature
• Add str_contains() function
  • new feature
• Deprecate curly brace syntax for accessing array elements and string offsets
  • update existing code
  • new feature (already implemented)
• Change the precedence of the concatenation operator
  • update existing code
  • new feature
• Remove inappropriate inheritance signature checks on private methods
  • update existing code
  • new feature (already implemented)
• Deprecate left-associative ternary operator
  • update existing code
  • new feature
• Add Stringable interface
  • update existing code (PHP8 #5166)
  • new feature
• Date: mktime() and gmmktime() now require at least one argument. time() can be used to get the current timestamp.
  • update existing code
  • new feature (PHP8 #5166)
• Exif: Removed read_exif_data(). exif_read_data() should be used instead.
  • update existing code
  • new feature (PHP8 #5166)
• The imap_header() function which is an alias of imap_headerinfo() has been removed.
  • update existing code
  • new feature (already implemented)
• parse_str() can no longer be used without specifying a result array.
  • update existing code
  • new feature (not we can do)
• Calling implode() with parameters in a reverse order ($pieces, $glue) is no longer supported.
  • update existing code
  • new feature (already implemented)
• Mbstring A number of deprecated mbregex aliases have been removed.
  • update existing code
  • new feature (already implemented)
• Namespaced names can no longer contain whitespace (nor comments)
  • update existing code
  • new feature (CleanNamespaceFixer - Introduction #5264)
• PHP 8.0 migration rule set (PHP8 #5166)
• PHP 8.0 integration test (tests/Fixtures/Integration/misc/PHP8_0.test) ensuring all new syntaxes are passing complex ruleset like @Symfony or @PhpCsFixer:risky) (Add PHP8 integration test #5399)
• Update Travis GitHub Actions with dedicated PHP8 job

- GMP:
  . gmp_random() has been removed. One of gmp_random_range() or
    gmp_random_bits() should be used instead.

- OCI8:
  . The OCI-Lob class is now called OCILob, and the OCI-Collection class is now
    called OCICollection for name compliance enforced by PHP 8 arginfo
    type annotation tooling.
  . Several alias functions have been marked as deprecated.

- Reflection:
  . The method signatures
        ReflectionClass::newInstance($args)
        ReflectionFunction::invoke($args)
        ReflectionMethod::invoke($object, $args)

    have been changed to:
        ReflectionClass::newInstance(...$args)
        ReflectionFunction::invoke(...$args)
        ReflectionMethod::invoke($object, ...$args)

    Code that must be compatible with both PHP 7 and PHP 8 can use the following
    signatures to be compatible with both versions:
        ReflectionClass::newInstance($arg = null, ...$args)
        ReflectionFunction::invoke($arg = null, ...$args)
        ReflectionMethod::invoke($object, $arg = null, ...$args)

Other changes that might require fixing existing tests and/or adding new ones:

• Object-based token_get_all() alternative
• Treat namespaced names as single token (PHP8 #5166)
• Don't include trailing newline in comment token
• SPL: SplFixedArray is now an IteratorAggregate and not an Iterator. (PHP8 #5166)

Additional source: https://github.com/php/php-src/blob/php-8.0.0rc1/UPGRADING

Note

• From now we only accept PR's that are compatible with PHP8
• Updating composer.json of the project will be done after all current functionality has been made compatible (new feature support can wait)
• We will keep the build step nightly as allowed to fail. When there is a dedicated Travis target for PHP8 we will add it to the steps

[mvorisek]

Union Types rule should definitely support sorting to prevent !n possible orders. Probably based on phpdoc rules where there is alrady option for it.

[julienfalque]

Note that this issue is not about implementing new rules but making sure that existing rules do not break with new PHP 8.0 syntax changes. Nice suggestion though 👍

[GrahamCampbell]

More changes to the lexer: sebastianbergmann/php-token-stream#95. (php/php-src#5182)

[GrahamCampbell]

@SpacePossum that RFC has been rejected. Voting closed yesterday, and they failed to get a 2/3 majority (only managed 58.9%).

[hamdrew]

@GrahamCampbell can you link the RFC? php/php-src#5182 appears to be accepted and merged (despite the closed PR status).

[hamdrew]

Would a dedicated Travis CI job for PHP 8.0 be a part of the definition of done for this issue? I know there is a nightly builds job, but that differs from pointing to a release of PHP 8.0 (even if it is beta).

[julienfalque]

Would a dedicated Travis CI job for PHP 8.0 be a part of the definition of done for this issue?

If Travis CI supports dedicated PHP 8.0 jobs, I would say yes.

[GrahamCampbell]

#5114 gets us started with some stuff. If anyone could work out why that\s not working, that'd be a help.

[hamdrew]

PHP 8.0 Wiki Page and Timetable - GA Release 11/26/2020

PHP 8.0.0RC1 Upgrade Notes - information on new features and backwards-incompatible changes.

Implemented RFCs for 8.0 - a good place to learn of language changes that would most affect this project

[hamdrew]

I took some time to review all the core changes in the upgrade notes and their respective RFCs. I picked out the ones that had syntax changes, or I otherwise felt might break a rule.

I created a Google Sheet to track these potentially rule-breaking changes. Anyone can comment on this sheet. Please request edit permissions if desired:

removed link to avoid confusion

This is just a quick-and-dirty organization technique for myself that I thought would be useful; if there is a better place to organize this (like in this GitHub issue description?) let me know.

Edit: PHPCompatibility has a nice checklist of changes as well. I also like how they organized the tasks.

[julienfalque]

@hamdrew To be honest I prefer tracking PHP changes here, I updated the description. Hopefully I didn't forget anything important.

[hamdrew]

@julienfalque I agree! I removed the link to avoid confusion.

Last night I set up a PHP 8 docker environment to develop from. I share it here if anyone finds it useful: https://github.com/hamdrew/PHP-CS-Fixer-Docker

I didn't want to contribute a docker development environment directly to this project because that is a large discussion that doesn't need to happen right now.

[hamdrew]

I addressed the SplFixedArray issue first in #5167, since it was prohibiting a lot of tests from running.

@SpacePossum To what branch would you like php8-related PRs to be targeted? I chose master for now.

[SpacePossum]

Thanks @hamdrew for the work in the PR!
Currently I'm working in PHP8 support as well in #5166 , for now I picked 2.15 to see what we can do for as many as branches we support.

[hamdrew]

@SpacePossum Cool, I'll target the same branch in my PRs to be consistent.

[GrahamCampbell]

Related: PHP-CS-Fixer/diff#19.

[SanderSander]

Based on the reasoning to not allow usage of the tool in #5341

The result running PHP CS Fixer on code with it is not known, currently.
We already had a case when PHP 8 code was parsed, changed by fixer and produced valid PHP syntax, but with different meaning. We don't want to offer that to users of the tool. In our opinion it's better to not offer the tool than offer the tool and break the code logic.

Would it be an idea to give the user a warning when someone uses ./vendor/bin/php-cs-fixer with PHP 8.0 instead of terminating execution?

[keradus]

or at least the info how to use PHP_IGNORE_ENV.
would you mind to add that note, @SanderSander ?

[SanderSander]

@keradus Ah sorry guess I'm getting tired that would be way better 😅 I will add some documentation about PHP_CS_FIXER_IGNORE_ENV

[keradus]

2.18 with PHP8 enabled was released. If you would spot any issues with it, raise a new ticket.

I'm leaving this meta-ticket open, as it still contains plenty of ideas for new rules.

[SpacePossum]

I'm going to close here as a lot of work has been done and having new dedicated issues for each item will be much easier to track going forward. Thanks all for sharing information, thoughts and options, great work 👍 : )