Whitelist PHP methods for no return or arg type

See #11

Author: gmazzap

CHANGELOG.md

@@ -1,11 +1,14 @@
 # Changelog
 
+## Not released
+- Whitelist PHP core methods for not having return or argument type declaration.
+
 ## 0.12.0
 - Fix bug in `Psr4Sniff` when class has not namespace.
-- Allow @wp-hook ignore of return type for private and protected methods
-- Only check public accessors (by default)
-- Fix bug in checking return type
-- Allow filters callbacks to return `null` on purpose
+- Allow @wp-hook ignore of return type for private and protected methods.
+- Only check public accessors (by default).
+- Fix bug in checking return type.
+- Allow filters callbacks to return `null` on purpose.
 
 ## 0.11.0
 - Fix false positive in `ReturnTypeDeclarationSniff` with nullable types.
@@ -15,7 +18,7 @@
 - Added `VariablesNameSniff`.
 - Improved `PhpcsHelpers::variableIsProperty()`.
 - Improved failure handling in FixturesTest.
-- Use NeutronStandard by opting-in rules instead of opting-out
+- Use NeutronStandard by opting-in rules instead of opting-out.
 - Properly handle Generators and return types.
 
 ## 0.10.0

Inpsyde/Sniffs/CodeQuality/ArgumentTypeDeclarationSniff.php

@@ -28,6 +28,11 @@ class ArgumentTypeDeclarationSniff implements Sniff
         T_SELF,
     ];
 
+    const METHODS_WHITELIST = [
+        'unserialize',
+        'seek',
+    ];
+
     /**
      * @inheritdoc
      */
@@ -44,6 +49,10 @@ public function process(File $file, $position)
         if (PhpcsHelpers::functionIsArrayAccess($file, $position)
             || PhpcsHelpers::isHookClosure($file, $position)
             || PhpcsHelpers::isHookFunction($file, $position)
+            || (
+                PhpcsHelpers::functionIsMethod($file, $position)
+                && in_array($file->getDeclarationName($position), self::METHODS_WHITELIST, true)
+            )
         ) {
             return;
         }

Inpsyde/Sniffs/CodeQuality/ReturnTypeDeclarationSniff.php

@@ -29,6 +29,19 @@ class ReturnTypeDeclarationSniff implements Sniff
         T_SELF,
     ];
 
+    const METHODS_WHITELIST = [
+        '__to_string',
+        'serialize',
+        'jsonSerialize',
+        'getIterator',
+        'getInnerIterator',
+        'getChildren',
+        'current',
+        'key',
+        'valid',
+        'count',
+    ];
+
     /**
      * @inheritdoc
      */
@@ -144,6 +157,12 @@ private function maybeErrors(
             return;
         }
 
+        if (PhpcsHelpers::functionIsMethod($file, $position)
+            && in_array($file->getDeclarationName($position), self::METHODS_WHITELIST, true)
+        ) {
+            return;
+        }
+
         if ($hasNoReturnType) {
             $file->addWarning('Return type is missing', $position, 'NoReturnType');
         }

tests/fixtures/argument-type-declaration.php

@@ -243,3 +243,15 @@ public function offsetUnset($offset)
     {
     }
 }
+
+class SerializeTest implements \Serializable {
+
+    public function serialize()
+    {
+        return '';
+    }
+
+    public function unserialize($serialized)
+    {
+    }
+}

tests/fixtures/return-type-declaration.php

@@ -409,3 +409,20 @@ public function iReturnWrongNull(): \ArrayAccess
         return new \ArrayObject();
     }
 }
+
+class JsonSerializeTest implements \JsonSerializable, \Serializable {
+
+    public function jsonSerialize()
+    {
+        return '';
+    }
+
+    public function serialize()
+    {
+        return '';
+    }
+
+    public function unserialize($serialized)
+    {
+    }
+}