Coming from https://github.com/ramsey/uuid/pull/603, this is an attempt
to fix the errors raised by the current phpstan settings.
I went through each of the errors raised by phpstan with the following
approach.
- If a method is part of an `@immutable` class, we can consider it pure,
assuming it only affects internal variables.
- If a potentially pure method is calling a class's method that is only
swapped during testing (and not during normal usage), then we can
consider the calling method pure.
- If a class is marked deprecated, don't bother with attempting to mark
it pure or immutable.
As documented in https://wiki.php.net/rfc/use_global_elements, the engine (by default) does a local namespace
lookup, then falls back to global namespace when first calling a global function referenced in namespaced code,
unless that function is referenced via fully qualified name (FQN).
By using the FQN, the actual symbol can be looked up at compile-time, both by the PHP engine and by static analysis
tooling, allowing for compiler (in particular) optimizations to replace known hot-path functions with specialized opcodes.
Sadly, no actual benchmark at hand: the improvements can be minimal or massive, depending on where this library is
used (tight loops being most relevant).
Ben Ramsey
Brandon Morrison
Ben Ramsey
Marco Pivetta