encouraging snake_case dynamic segments results in routes erroring upon creation

[mike-north]

Using the default lint configuration developers get from running ember new, after creating a route with the prescribed best practice of snake_case dynamic segment names (i.e., :foo_id) results in routes throwing errors immediately upon creation.

To Reproduce

ember new abc
cd abc
ember g route book --path="book/:book_id"
ember s
visit http://localhost:4200/book/42

You will get one of the following errors, depending on ember version

Error: No model was found for 'book'

or

Uncaught (in promise)
Error: Assertion Failed: You used the dynamic segment team_id in your route team,
but abc.Book did not exist and you did not override your route's `model` hook.

Suggested Solution

By encouraging developers to use snake_case dynamic segments in the lint rules, we're steering more developers into the path of the frequently-confusing default Route#model hook behavior (whereby, even in the absence of a custom model hook a snake_case dynamic segment name like :book_id, the store is queried for a record of type 'book' whose id is whatever value is found in the segment).

I think this should be an opt-in rule instead of being part of the default ruleset for the following reasons

1. We're steering people toward a highly unintuitive rough spot in the framework (aforementioned model hook default behavior)

2. The rationalization for this is rule is based on performance concerns around a router implementation detail (tbh I don't even know if this is true anymore?)

Dynamic segments in routes should use snake case, so Ember doesn't have to do extra serialization in order to resolve promises.

I haven't measured this, but I have a suspicion that even if there is a performance concern, it won't even be observable except in the very largest apps

3. Once we put the alleged performance penalty aside, this is just a stylistic choice, and we should leave this kind of thing in the hands of developers (same with tabs vs. spaces, single vs. double quotes, etc...)

4. The snake_case default clashes with the enabled-by-default camelcase eslint rule in places like this

class Route {
    model(params) {
        const { book_id } = params;
    }
}