Fix notices and failure of deploy static content

[convenient]

System notes

The following is run on

• the current develop branch
• on a fresh install of m2
• on OSX
• mode set to developer
• PHP 7.0.9
• Fixes Unable to run deploy:mode:set production #7108

The Error

bin/magento setup:static-content:deploy -f
Requested languages: en_US
Requested areas: adminhtml, frontend
Requested themes: Magento/backend, Magento/blank, Magento/luma

  [Exception]
  Notice: Undefined index: arguments in /src/mtwo/lib/internal/Magento/Framework/ObjectManager/Config/Compiled.php on line 132

The problem
I think this issue was introduced with this section of code which adds a fake cache class for static content deployments: DeployStaticContentCommand.php#L493

    private function mockCache()
    {
        $this->objectManager->configure([
            'preferences' => [
                Cache::class => DummyCache::class
            ]
        ]);
    }

This calls configure on the object manager which has a constructor like

    public function __construct($data)
    {
        $this->arguments = $data['arguments'];
        $this->virtualTypes = $data['instanceTypes'];
        $this->preferences = $data['preferences'];
    }

see ObjectManager/Config/Compiled.php#L34 for more

As the fake cache command only passes in the preferences argument we get a notice for arguments and we'd get one for instanceTypes if it got that far. Even if we suppress notices things still won't work, as we'd be wiping out all the legitimate configuration for the di config.

The solution

I think the solution for this would be to do a selective update of the diConfig so that we're only mocking out the cache class and leaving the remainder untouched.

To do this I had to expose the entirety of the arguments stored in the config. This seems to allow the command to run and do its thing. After a di recompile the world seemed to be working again.

A caveat, this is my first foray into the M2 configuration and DI system, my solution could be totally whack. Feel free to say point me in the correct direction if I'm doing something silly 👍

[convenient]

The failing tests look legit, i'll get around to them tomorrow.

[PascalBrouwers]

@dthampy this one seems related to #7108

[convenient]

Good spot @PascalBrouwers, it does appear to be the same issue doesn't it.

[AVoskoboinikov]

Hi, guys this issue was already fixed in develop branch. Check this commit f6f3cf8

[convenient]

@AZVO I got there first by a few days ;)

But f6f3cf8 is by far a better solution, seems legit.

Could you cherry-pick in a42ed22 ? it's a simple typo fix.