MAGETWO-61422 Respect Category Top Navigation Max Depth setting

[arnoudhgz]

Description

The setting Stores > Configuration > Catalog > Catalog > Category Top Navigation > Maximal Depth was actually never being used to limit the top menu maximum depth.

Now the setting will be used as a condition for the category collection when it is fetched.

Fixed Issues

1. Category Top Navigation / Maximal Depth configuration not working #7543: Category Top Navigation / Maximal Depth configuration not working

Manual testing scenarios

1. Change the setting in the backend
2. Refresh the invalidated cache
3. See that the setting actually is being used

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-cicd2]

All committers have signed the CLA.

[arnoudhgz]

@lenlorijn can you sign the 'Contributor License Agreement'?

[lenlorijn]

I signed the Contributor License Agreement :)

[mzeis]

FYI: I will fix the Travis error regarding maximum line length after the holidays. Suppressing CouplingBetweenObjects in this case is ok because it would mean a major refactoring for the frequently used parent classes.

[mzeis]

@arnoudhgz I hope you had a good start into the new year! I finally got around to check your PR and think there might be a change necessary to make this work as intended.

Please can you have a look at the code review?

Thanks!

[mzeis]

In my test, this looks like it doesn't work as intended. If I set a maximum depth of 1, no category is shown. If I set the value to 2, the top level category is displayed. If we add 1 to $navigationMaxDepth like $this->addLevelFilter($navigationMaxDepth + 1), it works like I would expect it to. I guess that's because the root category level also has to be considered.

[arnoudhgz]

No, that seems not like a good solution to me. I think we should adhere to the levels on http://docs.magento.com/m2/ee/user_guide/catalog/navigation-top.html

So in the admin configuration you have to use 2 for the first level.

[mzeis]

You are absolutely right. Thank you for pointing this out. The PR works as intended.

[mzeis]

Thanks for your contribution @arnoudhgz! It has been merged into 2.3-develop.