[FEATURE] Add rector/type-perfect PHPStan rules (#1599)

This package provides some opiniated PHPStan rules to make
our code more explicit and easier to read.

https://github.com/rectorphp/type-perfect

As our code already is in pretty good shape, the new rules do
not create any new warnings.

Also add some blank lines to the PHPStan configuration file to
make it more readable.

Fixes #1335

composer.json

@@ -59,6 +59,7 @@
 		"phpstan/phpstan-phpunit": "1.4.2",
 		"phpstan/phpstan-strict-rules": "1.6.1",
 		"phpunit/phpunit": "9.6.22",
+		"rector/type-perfect": "1.0.0",
 		"saschaegerer/phpstan-typo3": "1.10.2",
 		"seld/jsonlint": "1.11.0",
 		"spaze/phpstan-disallowed-calls": "4.3.1",

phpstan.neon

@@ -30,6 +30,13 @@ parameters:
     class: 10
     function: 5
 
+  type_perfect:
+    no_mixed_property: true
+    no_mixed_caller: true
+    null_over_false: true
+    narrow_param: true
+    narrow_return: true
+
   disallowedFunctionCalls:
     -
       function:
@@ -40,12 +47,14 @@ parameters:
     -
       function: 'header()'
       message: 'Use PSR-7 API instead'
+
   disallowedStaticCalls:
     -
       method:
         - 'TYPO3\CMS\Extbase\Utility\DebuggerUtility::var_dump()'
         - 'TYPO3\CMS\Core\Utility\DebugUtility::debug()'
       message: 'Use logging instead or remove if it was for debugging purposes.'
+
   disallowedSuperglobals:
     -
       superglobal:
@@ -54,6 +63,7 @@ parameters:
         - '$_FILES'
         - '$_SERVER'
       message: 'Use PSR-7 API instead'
+
   ignoreErrors:
     -
       message: '#Out of 1 possible constant types#'