php:S2014 ("$this" should not be used in a static context) is issued when I use $this within a anonymous function which is used within a static method.
For example:
static function someStaticMethod()
{
// Some code
SomeClass::someStaticMethod(function() {
return $this->getName(); // php:S2014 reported
});
// More code
}
This is possibly issued because someStaticMethod() is static, and thus the $this variable is believed to be unavailable. This message would normally be correct.
However, in this case, the $this variable appears within an anonymous function, which has the runtime type of a Closure class. $this bound when the closure is executed, rendering $this valid. This has been implemented since PHP 5.4.
The report can be reproduced with the following code.
<?php
class SonarTest {
public static function phpS2014() {
$person = new Person(7, 'Jack');
return Utils::map($person, function() { // Closure
return $this->name; // $this refers to a Person object, and
// not to anything from the SonarTest
// class
});
}
}
class Utils {
public static function map(Person $p, \Closure $mappingFunction) {
return $mappingFunction->call($p);
// The passed Person object is the $newThis. That means that if
// the given closure uses the $this variable, it refers to the
// Person object passed to this map() function.
}
}
class Person {
public $id;
public $name;
public function __construct(int $id, string $name) {
$this->id = $id;
$this->name = $name;
}
}
var_dump(SonarTest::phpS2014());
The above code will print
string(4) "Jack"
I’m running on PHP 7.1.
I’m using SonarCloud.