Coding standard to enforce backslash on function calls outside of a namespace

Added a very basic line of what we need to add. Should be refined.

Attaching screenshot of Drupal Core (11.x) code search. Looks like many things have been fixed already between Drupal 9/10 to 11 as I can find many more occurrences in our projects (might come from patches as well of course).

Thanks for opening this!

The current documentation on reads:

Classes and interfaces without a backslash \ inside their fully-qualified name (for example, the built-in PHP Exception class) must be fully qualified when used in a namespaced file. For example: new \Exception();. Do not use global classes.

It seems we’d just need to remove the “when used in a namespaced file” part?

Adding myself as a supporter. Also fixing the title – this is not about function calls but about references to classes (for static method calls, constructing new objects or just the ::class reference).

It seems we’d just need to remove the “when used in a namespaced file” part?

Probably yes, and update coder/phpcs to check for this.

This comes up in our pull requests a lot as well. My preference is to not include the backslash but I think I'm in the minority.

My preference is for a coding standard and consistency. It looks like the precedent generally is to include the backslash, so lending my support for this change.