feat: add relations option to tree queries

[TheProgrammer21]

Add possibility to load relations of tree entities

Description of change

The change adds an optional options parameter to the findTrees() function.
The only option that can currently be set is relations which is an array of all relations that should be loaded for the entities. It works the same way as the relations array for the find() method.

Example:

await connection.getTreeRepository(Category).findTrees({ relations: ["sites"] });

Results in:

[
  Category {
    pk: 1,
    title: 'Category 1',
    sites: [ [Site], [Site] ],
    childCategories: [ [Category] ]
  },
  Category {
    pk: 2,
    title: 'Category 2',
    sites: [],
    childCategories: []
  }
]

Because findTrees() is depending on the findDescendantsTree() and findRoots() functions those two also implement this new optional options parameter.

Currently it is not possible to load relations for tree entities in a single query. This is a much requested and needed feature, it would be great if it could be merged very soon!

I created test cases to ensure the functionality.

Closes: #7974 #4564

Pull-Request Checklist

• Code is up-to-date with the master branch
• npm run lint passes with this change
• npm run test passes with this change
• This pull request links relevant issues as Fixes #0000
• There are new or updated unit tests validating the change
• Documentation has been updated to reflect this change
• The new commits follow conventions explained in CONTRIBUTING.md

Could you please tell me when you are planning to merge this pull request? Thank you!

[TheProgrammer21]

I had to update the files manually because deactivating prettifier didn't change anything automatically. Could you please add the information to the development/contribution guide?

Everything should be updated as requested now!

[TheProgrammer21]

@pleerock / @imnotjames Can this functionality be merged now?

[pleerock]

Thank you for contribution! 🎉

[isabela-morais]

@pleerock / @imnotjames Do you have any prediction of when this will be released?

[spiotr12]

could the same options be added to findDescendants, findAncestors and findAncestorsTree?

[TheProgrammer21]

could the same options be added to findDescendants, findAncestors and findAncestorsTree?

findDescendantsTree also has this property since this pull request - the other 2 not. You can create an issue for those 2.

[spiotr12]

could the same options be added to findDescendants, findAncestors and findAncestorsTree?

findDescendantsTree also has this property since this pull request - the other 2 not. You can create an issue for those 2.

Created: #8076

[ab958]

there is no where and select available in .findTrees