composer show --direct with a specific package should exit with an error

[soullivaneuh]

With the given composer.json:

{
    "type": "project",
    "require": {
        "slevomat/coding-standard": "^8.14"
    },
    "config": {
        "allow-plugins": {
            "dealerdirect/phpcodesniffer-composer-installer": true
        },
        "sort-packages": true
    },
    "autoload": {
        "psr-4": {
            "App\\": "src/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "App\\Tests\\": "tests/"
        }
    }
}

The compose show command displays the following:

dealerdirect/phpcodesniffer-composer-installer v1.0.0 PHP_CodeSniffer Standards Composer Installer Plugin
phpstan/phpdoc-parser                          1.24.3 PHPDoc parser with support for nullable, intersection and generic types
slevomat/coding-standard                       8.14.1 Slevomat Coding Standard for PHP_CodeSniffer complements Consistence Coding Standard by providing sniffs with a...
squizlabs/php_codesniffer                      3.7.2  PHP_CodeSniffer tokenizes PHP, JavaScript and CSS files and detects violations of a defined set of coding stand...

With the --direct option:

slevomat/coding-standard 8.14.1 Slevomat Coding Standard for PHP_CodeSniffer complements Consistence Coding Standard by providing sniffs with additional checks.

If we specify a not installed package to the composer show command, like composer show not/existent, we got the following error:

In ShowCommand.php line 300:
                                                                                                
  Package "not/existent" not found, try using --available (-a) to show all available packages.  

And the command exit with an error code.

I would like to combine this behavior in combination with the --direct option to ensure a package is installed and required by the root package itself.

However, if I try with composer show --direct squizlabs/php_codesniffer, which is installed but not explicitly required, the commands successfully display the package information instead of exiting with an error code.

I would like an option to ensure a package is directly required by the root package and make the command throwing an error otherwise, like the sample above.

What do you think about this idea?

Regards

[fredden]

@soullivaneuh you may be interested in https://github.com/maglnet/ComposerRequireChecker. It's a tool that helps ensure that dependencies are declared properly. I can't quite tell from the description you have provided if this meets your needs or not. Why are you trying to work out if a particular package is listed as a direct dependency for a project?

[Seldaek]

Sounds reasonable to me to fix this behavior. It was just not considered I believe because if the package is there we just show it, and direct is only used for listing right now, but it wouldn't hurt to check for directness when requesting a single package IMO. If you like to PR it..