Flex: ParallelDownloader suddenly crashes (v1.0.81)

[ro0NL]

To reproduce:

composer create-project symfony/skeleton foo && cd foo && composer require orm

Result:

Installing symfony/skeleton (v4.1.0)
  - Installing symfony/skeleton (v4.1.0): Downloading (100%)         
Created project in foo
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 21 installs, 0 updates, 0 removals
  - Installing symfony/flex (v1.0.81): Downloading (100%)         

Prefetching 20 packages 🎶
  - Downloading (100%)

  - Installing symfony/polyfill-mbstring (v1.8.0): Loading from cache
  - Installing symfony/console (v4.1.1): Loading from cache
  - Installing symfony/routing (v4.1.1): Loading from cache
  - Installing symfony/yaml (v4.1.1): Loading from cache
  - Installing symfony/framework-bundle (v4.1.1): Loading from cache
  - Installing symfony/http-kernel (v4.1.1): Loading from cache
  - Installing symfony/http-foundation (v4.1.1): Loading from cache
  - Installing symfony/event-dispatcher (v4.1.1): Loading from cache
  - Installing psr/log (1.0.2): Loading from cache
  - Installing symfony/debug (v4.1.1): Loading from cache
  - Installing symfony/finder (v4.1.1): Loading from cache
  - Installing symfony/filesystem (v4.1.1): Loading from cache
  - Installing psr/container (1.0.0): Loading from cache
  - Installing symfony/dependency-injection (v4.1.1): Loading from cache
  - Installing symfony/config (v4.1.1): Loading from cache
  - Installing psr/simple-cache (1.0.1): Loading from cache
  - Installing psr/cache (1.0.1): Loading from cache
  - Installing symfony/cache (v4.1.1): Loading from cache
  - Installing symfony/dotenv (v4.1.1): Loading from cache
Writing lock file
Generating autoload files
Symfony operations: 4 recipes (04c4a9fa1a98c2ae2e3cb3994af56bd7)
  - Configuring symfony/flex (>=1.0): From github.com/symfony/recipes:master
  - Configuring symfony/framework-bundle (>=3.3): From github.com/symfony/recipes:master
  - Configuring symfony/console (>=3.3): From github.com/symfony/recipes:master
  - Configuring symfony/routing (>=4.0): From github.com/symfony/recipes:master
Executing script cache:clear [OK]
Executing script assets:install public [OK]

Some files may have been created or updated to configure your new packages.
Please review, edit and commit them: these files are yours.


 What's next? 


  * Run your application:
    1. Change to the project directory
    2. Create your code repository with the git init command
    3. Execute the php -S 127.0.0.1:8000 -t public command
    4. Browse to the http://localhost:8000/ URL.

       Quit the server with CTRL-C.
       Run composer require server --dev for a better web server.

  * Read the documentation at https://symfony.com/doc

/app/foo
Using version ^1.0 for symfony/orm-pack
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)

Fatal error: Uncaught Error: Function name must be a string in /app/vendor/symfony/flex/src/ParallelDownloader.php:246
Stack trace:
#0 /app/vendor/symfony/flex/src/ParallelDownloader.php(84): Symfony\Flex\ParallelDownloader->getNext()
#1 phar:///usr/bin/composer/src/Composer/Plugin/PluginManager.php(195) : eval()'d code(452): Symfony\Flex\ParallelDownloader->download(Array, Object(Closure))
#2 [internal function]: Symfony\Flex\Flex_composer_tmp0->populateProvidersCacheDir(Object(Composer\Installer\InstallerEvent))
#3 phar:///usr/bin/composer/src/Composer/EventDispatcher/EventDispatcher.php(171): call_user_func(Array, Object(Composer\Installer\InstallerEvent))
#4 phar:///usr/bin/composer/src/Composer/EventDispatcher/EventDispatcher.php(135): Composer\EventDispatcher\EventDispatcher->doDispatch(Object(Composer\Installer\InstallerEvent))
#5 phar:///usr/bin/composer/src/Composer/Installer.php(470): Composer\EventDispatcher\EventDispatcher->dispatchInstallerEvent('pre-dependencie...', true, Object(Composer\DependencyResolver\D in /app/vendor/symfony/flex/src/ParallelDownloader.php on line 246

[sstok]

Note (re)running composer require orm produces the same error. nextCallback is NULL for some reason, but this is a bit to complex for my mind 🤪🧙🏼‍♂️

[renanbr]

Same error for me. I have Composer 1.6.5, PHP version: 7.2.7-0ubuntu0.18.04.2, hirak/prestissimo 0.3.7 and phpstan/phpstan 0.10.1 installed.

[lpj145]

Omg.... i wake and code.... broken on this error.....

[xabbuh]

Does it work again when you downgrade to Flex 1.0.80?

[Macavity]

For us it does work after fixating on flex version 1.0.80.

[andre-qup]

Same here, 1.0.81 came with 2 bugs: this one and #382.

It seems that if you have private repos, #382 will affect you. If you don't use private repos, #381 will affect you: tested by removing all my private repo dependencies. Locking to 1.0.80 does fix both problems.

[hotrush]

Same here, 1.0.80 works

[fabpot]

I've just released 1.0.82 (which is the same as 1.0.80) as a hotfix.

[xabbuh]

I think this could as well be fixed by #384.

[fabpot]

v1.0.83 is out with a fix, can you test and report?

[ArjenMiedema]

Seems like the issue was fixed in 1.0.87, but is reintroduced in 1.0.88. Getting the error right away after I added a custom repository to my composer.json file.

[fabpot]

@nicolas-grekas

[nicolas-grekas]

OK, I reproduce, I'm on it.