PHP 7.0 coding standards revision

Problem/Motivation

PHP 7.0 will bring some new features that need some coding standard decisions. How we want to format anonymous classes is the largest among them. There are also some gray areas in the current standards that aren't significant enough to warrant tightening on their own, but could be included in a larger sweep. Creating this ticket now to allow some time (over a year) for debate. The decisions around this issue ticket should be finalized before the first version of Drupal that does not support PHP 5, else any code written to use newer PHP 7 features will be doing so without coding standard guidelines.

Note:I'm not proposing changing any existing code standard - this is an expansion.

Proposed resolution

These are the current items on discussion.

#Function Declarations

There is no current rule on multiple arguments, especially multiple type hinted arguments. Consider the following out of the DrupalKernel class

public static function createFromRequest(Request $request, $class_loader, $environment, $allow_dumping = TRUE, $app_root = NULL) {

This is already over 80 characters by a long shot, and under PHP 7.0 we would want to enforce the scalar types and return as follows:

public static function createFromRequest(Request $request, $class_loader, string $environment, bool $allow_dumping = TRUE, string $app_root = NULL) : DrupalKernel {

Consider the following alternatives:

// Function with argument list less than 80 characters.
public static function createFromRequest( Request $request ) : DrupalKernel {
}
// Function with argument list more than 80 characters, with return type.
public static function createFromRequest(
  Request $request, 
  $class_loader, 
  string $environment, 
  bool $allow_dumping = TRUE, 
  string $app_root = NULL
) : DrupalKernel {
}
// Without return type
public function foo (
  $a,
  $b
) {

Note the above mimics the existing coding standards for arrays.

#Anonymous Classes

Here's the PHP page example.

$app->setLogger(new class implements Logger {
    public function log(string $msg) {
        echo $msg;
    }
});

This seems in line with what we already do, and it's similar enough to anonymous functions that we might just add an example and not actually change anything.