Major new features 🚀

• Support for PHP 8.1 Enums - RFC
  • Thanks to @kukulich for custom Enum rules!
• Upgraded Roave/BetterReflection to 5.0.0
  • PHP 7.1+ is still supported because the dependency is downgraded automatically in our own fork
  • This brings plenty of bugfixes, for example PHP 8.0 Attributes can now be read in static reflection context
• PHPStan now works when OPCache is enabled!
  • Thanks to this commit: phpstan/phpstan-src@e30f446
• The development repository phpstan/phpstan-src is now PHP 8.0+ only, while the distribution package phpstan/phpstan still supports PHP 7.1+.
  • This is achieved thanks to automatic downgrade of source code using Rector during PHAR compilation
  • PHPStan now ships with Symfony PHP polyfills for PHP 7.2-8.0.

Improvements 🔧

• Update nikic/php-parser to 4.13.2 (phpstan/phpstan-src@8939964)
• Update to Symfony 5.4 (#863)
• CLI option --allow-empty-baseline to allow generating empty baseline (#776), thanks @Lctrs!
• Support for @phpstan-property, @phpstan-property-read, and @phpstan-property-write (#775), thanks @mad-briller!
• Add support for the key-of<...> and value-of<...> types (#800), thanks @ste93cry!
• GithubErrorFormatter > Allow any ErrorFormatter (#854), thanks @ruudk!
• Array unpacking support for string-keyed arrays (#803), thanks @canvural!
• Moved some classes from ClassBlacklistReflectionProvider to staticReflectionClassNamePatterns config so that they are in effect for ClassBlacklistSourceLocator too (phpstan/phpstan-src@e40ba15)
• PHPStanTestCase: Added a helper method to assert no errors happend (#894), thanks @staabm!

Bugfixes 🐛

• Resolve deprecated tag also from parents (#792), thanks @eiriksm!
• echo isn't callable either. (#777), thanks @johnbillion!
• Resolve object type by class const fetch in switch statement (#745), thanks @marmichalski!
• Allow also $object::class with Identical (#745), thanks @marmichalski!
• Fixed ErrorFormatter tests in terminals with console support (#805), thanks @kukulich!
• Copy all environment variables when running PHPStan Pro (phpstan/phpstan-src@e61ad95), #5433
• Allow destructuring of objects implementing ArrayAccess (#819), thanks @herndlm!
• Spreading of general arrays should not lead to a non-empty-array (#818), thanks @herndlm!
• Simplify FileTypeMapper (phpstan/phpstan-src@256d11b)
• Make FileTypeMapper more deterministic (phpstan/phpstan-src@ae6dca5)
• Fix normal vs. stub PHPDoc (phpstan/phpstan-src@e9dd3a3)
• ReflectionAttribute is no longer final class (phpstan/phpstan-src@97e153c)
• ReflectionAttribute stub - IS_INSTANCEOF constant (phpstan/phpstan-src@cfb6fad)
• DependencyResolver - cause autoloading less often when looking at literal arrays (phpstan/phpstan-src@b927c87), #6187, #6096
• MemoizingReflectionProvider - cache hasClass() as case-sensitive (phpstan/phpstan-src@792ce0a), #6096
• XdebugHandler - setPersistent (#726), #5809, thanks @fsmoak!
• Simplify AutoloadSourceLocator - let it actually autoload the file (phpstan/phpstan-src@e30f446)
• AutoloadSourceLocator - filter classes by startLine only if there are multiple of them (#882)
• ComposerJsonAndInstalledJsonSourceLocatorMaker - fix for autoload-dev section (#882)
• TestCaseSourceLocatorFactory - skip invalid Composer locations (#882)
• Fix ReturnTypeRule (#882)
• Silent @ operator should use & $errno check (#889), thanks @samsonasik!
• ClassTemplateTypeRule should not be executed for interfaces (phpstan/phpstan-src@9adf6bf)
• MixinRule - check interfaces and enums (phpstan/phpstan-src@8519cca)

Function signature fixes 🤖

• Added DynamicReturnTypeExtension for trigger_error (#766), thanks @staabm!
• The array returned by array_count_values() can never contain a zero. (#773), thanks @johnbillion!
• Add ThrowableReturnTypeExtension (#795), thanks @herndlm!
• Update functionMap for XSLTProcessor (#797), thanks @hbrecht!
• imap_delete / imap_undelete: correction (#799), thanks @hbrecht!
• Fix the signature of the value returned from the date_parse and date_parse_from_format functions (#807), thanks @ste93cry!
• Fix the signature of get_resources() (#837), thanks @MidnightDesign!
• Fix preg_filter function signature (#826), thanks @johnstevenson!
• Fix ldap_set_rebind_proc signature (#851), thanks @villfa!
• restore_error_handler and restore_exception_handler always return boolean true. (#850), thanks @johnbillion!
• More specific return types for some DateTimeZone methods (#857), thanks @johnbillion!
• Add missing Set::map() method to ext-ds stub (#855), thanks @simPod!
• Support variable constant flags in preg_split (phpstan/phpstan-src@a16c7ae), thanks @clxmstaab!