Embed Sinatra

[lopopolo]

This branch is an ongoing effort to get the following code to parse and return a Rack app:

require 'sinatra/base'

class MyApp < Sinatra::Base
  set :sessions, true
  set :foo, 'bar'

  get '/' do
    'Hello world!'
  end
end

This branch is a top-down approach to implementing core and the standard library in contrast to the bottom up approach I've been taking with Regexp.

The supplied main function in the ditty crate will return MrbError until the code parses and compiles. Address errors as they come up.

Some things I've had to do so far:

• Import Ruby sources for standard library components from Ruby 2.6.3.
• Modify Ruby standard library components for the mruby VM (e.g. Thread, Monitor, Mutex).
• Patch gem sources to work around mruby limitations.

I anticipate needing to implement more of core and standard library in Rust.

[felipecsl]

solid

[lopopolo]

uri depends on String#scan, which depends on Regexp#match.

Once I get a working Regexp matcher, I can implement scan in pure Ruby, using a string pointer. Here is the prototype:

https://github.com/lopopolo/ferrocarril/blob/37034d455d75d39eae4be5ffdd458de98713e42b/mruby-sys/vendor/mruby-c078758/mrblib/string.rb#L108-L116

[lopopolo]

GH-89 and GH-92 were extracted from this PR and added Thread, Mutex, and Monitor implementations.

[lopopolo]

As of 6368f9f, Sinatra is able to successfully load the mustermann gem. This requires a stub implementation of StringScanner. Implementing the required methods on StringScanner is tracked in GH-91.

[lopopolo]

As of this most recent push, the ditty crate successfully initializes a Sinatra::Base Rack application and returns a 404 page.

(Showing the 404 page is a bug, but expected given the amount of stubbing going on.)

[lopopolo]

leak tests fail locally for me but seem to pass in CI. Will dig into this later.

[lopopolo]

Got an echo server running that outputs a JSON response containing the Rack request.

http://localhost:8000/boom succeeds
http://localhost:8000/boom?foo=bar blows up

[lopopolo]

It works!