THIS PROJECT IS NO LONGER ACTIVE; it is not needed with HHVM 3.25 and later.

Unless the hhvm.hack.lang.look_for_typechecker ini setting is set to false, by default HHVM will try to run the typechecker when loading any Hack files, and raise a catchable runtime fatal error.

This is a PHP library that makes it convenient to temporarily disable this behavior.

HHVM's behavior is problematic when:

• HHVM can't work out where the project root is - for example, if you're trying to run Hack code from a composer plugin
• If your Hack code needs to operate on an incomplete project - for example, if you wish to write Hack code to fetch dependencies
• If your Hack code needs to operate on known-bad projects - for example, when updating generated code, the code may be inconsistent while your codegen is in process

It's probably not appropriate if any of these are true:

• it's used outside of a build/install or codegen process
• it's used when using generated code
• it's called during normal use of your software, rather than just by developers
• it's used outside of the CLI

Typechecker errors are real problems with code, and mean that things are broken; ignoring enforcement is only a good idea if you are expecting your code to be running on a temporarily-broken codebase, and your code fixes it.

$ composer require fredemmott/hack-error-suppressor

You must enable error suppression before any Hack code is loaded.

You can explicitly enable and disable the suppression:

<?php
use FredEmmott\HackErrorSuppressor;

$it = new HackErrorSuppressor();
$it->enable();
call_some_hack_code();
$it->disable();

You can also enable the suppression with a scope:

<?php

use FredEmmott\ScopedHackErrorSuppressor;

function do_unsafe_stuff() {
  $suppressor = new ScopedHackErrorSuppressor();
  call_some_hack_code(); // this works
}

do_unsafe_stuff();
call_some_hack_code(); // this fails, as we're out of scope

This is disallowed by default; if you're absolutely certain you need to do this (keeping in mind that typechecker errors are real problems with your code, not just lint) you can disable the check:

FredEmmott\HackErrorSuppressor::allowRealRequestsAgainstBrokenCode();