Typechecker allows require_once $nullable_string

[fredemmott]

[fredemmott@devbig076 ~/hhtest] hh_client
No errors!
[fredemmott@devbig076 ~/hhtest] cat test.php
<?hh

function foo(?string $bar) {
  require_once $bar;
}

[jwatzman]

I assume from the context that require_once cannot take null?

[jwatzman]

Oof this is going to be obnoxious, our AST totally drops requires at the parse level.

[fredemmott]

Nope, require_once must take a string.

Couldn't the parser just rewrite it to require_once($foo) ? then we could just add an hhi

[lexidor]

I am going over old issues against this repository to reduce the amount of open issues.

The issue of require_once's "first argument" not being typechecked is still true in hhvm today.
It joins the other statement keywords in being untyped echo f.e.

However, because of changes in the ecosystem, this is becoming less and less relevant. When this issue was made hhvm-autoload did not exist yet, so require_once's in application code were far more common. These days, most Hack applications only require an autoloader vendor/autoload.hack and invoke Facebook\AutoloadMap\initialize(). Since top-level code (with the exception of declarations) was banned (even in partial mode), requiring a file for its side effects is no longer a thing. The only thing you can achieve using a require call, it bringing named entities into the request. However, because of autoloading, this is rarely if ever needed.