Dispatch to rules using a protocol.

[lpil]

See #171

Breaking changes ahoy.

• Dogma.Rule protocol
• defrule macro
• Rule.Case test macro
• All rules using defrule
• All rules tested using Rule.Case
• Rule sets updated to use structs
• Dogma using protocol to run rules
• Config generation handles new format
• Config supports old format
• Deprecation message for old format
• Config documentation updated
• No pending tests
• Changelog

[meadsteve]

small comment but if there are no default config values maybe

defrule Dogma.Rule.CommentFormat do

would be better.

[lpil]

Yeah, I should do that.

[lpil]

@meadsteve

Care to review?

Also, do you know how to go from a module atom name to the struct for that module?

i.e.

assert transform(LineLength) == %LineLength{}

I can't work it out.

[meadsteve]

@lpil I think the kernel function struct(struct, kv \\ [])might be what you're looking for. I'll take a look at this pr today when I get a chance.

[lpil]

Ah, thanks! I didn't think to look in kernel. :)

[meadsteve]

👍 like this approach to updating the config style. Neat way of emitting deprecations and the whole method can just be removed at the next major version bump.

One thing I'd think about though is whether it'd be better to do this as a logger.warn rather than just an IO.put. As it is a warning not just a message.

[lpil]

Currently the logger isn't running. I could add it but then I need to backport ExUnit.CaptureLog, as it isn't present in 1.0 :(

[meadsteve]

ah I see. That's a shame. In any case what you've done should still be useful.

[meadsteve]

what happens if test/2 isn't defined? Does it error on compile? (please ignore all of the following if it does error). One thought is to add a rule @behaviour so this starts something like:

quote do
   defmodule unquote(name) do
      alias Dogma.Error
      alias Dogma.Script

       @behaviour Dogma.RuleBehaviour

[lpil]

It compiles and crashes at runtime. I'll add the behaviour so it compiles with a warning.

[meadsteve]

A few comments from me but generally this approach looks really good. I like that the script module got smaller and more focussed.

[lpil]

Thanks Steve!