Parse "enum-like" fields as string, then implement API for matching it

[joao-paulo-parity]

As discussed in #219, decoding the "enum-like" fields from the API types has some problems

• Incurs unwarranted parsing errors due to untracked variants
• Adds extra burden to keep up with the API variants whenever Github decides to change it

#244 suggests a less error-prone interface like the following

enum EventAction {
  Foo
}

struct Event {
  action: String // String instead of EventAction; purposefully private
}

impl Event {
  pub fn is_action(&self, action: EventAction) -> bool {
    self.action == action.to_string()
  }
}

Using [variant].to_string() is less error-prone than working with literal strings since the latter is subject to typos.

[ordian]

I have an alternative suggestion, that doesn't require a string allocation: #244 (comment)

[joao-paulo-parity]

I have an alternative suggestion, that doesn't require a string allocation: #244 (comment)

Seems good, although I'd argue it's more error-prone since it requires the implementer to track if those annotations are put in the right places. Let's go with that, though.

[ordian]

I have an alternative suggestion, that doesn't require a string allocation: #244 (comment)

Seems good, although I'd argue it's more error-prone since it requires the implementer to track if those annotations are put in the right places. Let's go with that, though.

Yes, we need more tests ;)