Use random username in tests

[anuragsoni]

This is a first pass at using randomly generated user id's in tests

closes #121

[anuragsoni]

@mujx @jimmycuadra I haven't changed all occurrences of user_id's in tests yet. Updates will be required in all tests and I figured i'd do that if the approach that i've take here is agreeable to you guys.

[anuragsoni]

updated by removing create_access_token, create_access_token_with_username, and by returning the new user struct (by using the new create_user method) in create_fixtures instead of returning just a token.

[mujx]

Turns out there is already a random id generator in ruma-identifiers so we can use that. It is used in registration if a username isn't provided. The other option is to omit the username field and get a random one back.

[anuragsoni]

@mujx Ah, I hadn't seen ruma-identifiers. It looks to be the same thing that I had done in this PR so I replace my function with a call to the one from ruma-identifiers. As for the username, I find it nicer to have in the TestUser. I was generating the username randomly, but there are tests where we need both the username and the id. This field helps for that.

[mujx]

Yes we need to keep it inside TestUser. The registration endpoint will return a random username. So you can do json().find('username') to get it, if you want. Here is the response.

[anuragsoni]

that returns only the user_id?

#[derive(Debug, Serialize)]
struct RegistrationResponse {
    pub access_token: String,
    pub home_server: String,
    pub user_id: String,
}

[mujx]

That will return the fully qualified Matrix ID, ie @zikuoafjyyrh:ruma.test

[anuragsoni]

exactly. My point being that we need the id => @zikuoafjyyrh:ruma.test and the username: zikuoafjyyrh. If I register without the username, I'd need to access the random username that ruma_identifier creates. But I do not see it being returned in the RegistrationResponse struct? Maybe i'm missing something?

[mujx]

There is a helper method for UserId to get the localpart that you are reffering to. You can parse the returned UserId and call user_id.localpart() to the get the username you want. Another way to go is to store the id as UserId instead of String in the TestUser and call alice.localpart() in the tests.

[jimmycuadra]

This should be easier now with #158 merged!

[anuragsoni]

Updated to use the UserId from ruma_identifier, and squashed commits for cleanup

[jimmycuadra]

One minor thing to fix that I just noticed: We organize imports into three sections, separated by blank lines: 1) stdlib imports 2) external crate imports 3) internal imports. The two imports added to src/test.rs should be resorted accordingly. Go ahead and squash the commits again after that and I'll merge this. Thanks very much for doing this work—that was a lot of little things to change!

[anuragsoni]

@jimmycuadra I will keep that in mind for any change I work on in future! Updated with the imports re-ordered.

[jimmycuadra]

We'll probably add some minor style guide information to CONTRIBUTING.md soon, and eventually rustfmt will fix all of this nonsense.