myronmarston

defmodule Registry do
  # ...

  def handle_call({:execute_against_shard, campaign_id, fun}, from, state) do
    {shard_process, state} = find_or_create_shard(campaign_id, state)
    ShardProcess.execute_and_reply(shard_process, fun, from)
    {:noreply, state}
  end
  
  # ...

myronmarston

require 'rspec/core/rake_task'

RSpec::Core::RakeTask.new(:specs_prep) do |t|
  t.rspec_opts = "--out tmp/specs_task.out"
end

task :specs => :specs_prep do
  results = File.read("tmp/specs_task.out")
  # do something with results
end

myronmarston

RSpec.configure do |config|
  # Either put conditional logic in the hook...
  config.around(:example) do |ex|
    unless ex.metadata[:slow]
      puts "Not tagged slow"
    end

    ex.run
  end

myronmarston

A group of examples
  passes
  is pending (PENDING: not yet passing)
  fails (FAILED - 1)
  fails with a diff (FAILED - 2)
  fails with a multiline snippet in order to show off syntax highlighting (FAILED - 3)

Pending: (Failures listed here are expected and do not affect your suite's status)

myronmarston

HTTP/1.1 400 Bad Request
connection: close
server: Cowboy
date: Tue, 24 Nov 2015 20:24:58 GMT
content-length: 0

myronmarston

Using OTP's observer (appmon replacement) remotely

$ ssh remote-host "epmd -names"
epmd: up and running on port 4369 with data:
name some_node at port 58769

Note the running on port for epmd itself and the port of the node you're interested in debugging. Reconnect to the remote host with these ports forwarded:

$ ssh -L 4369:localhost:4369 -L 58769:localhost:58769 remote-host

myronmarston

defmodule Delorean.RankingsShardRepository.RunningShard.Supervisor do
  use Supervisor

  def start_link(opts) do
    Supervisor.start_link(__MODULE__, opts, [])
  end

  def start_shard(supervisor, shard_opts) do
    Supervisor.start_child(supervisor, shard_opts)
  end

myronmarston

defmodule MyApp.SnapshotRepositoryTest do
  use ExUnit.Case, async: true
  doctest MyApp.SnapshotRepository
  alias MyApp.SnapshotRepository.SnapshotOptions

  test "queries S3 with a prefix and returns the matched keys" do
    options = %SnapshotOptions{ campaign_id: "prod.0.1", backend: "SomeBackend", cycle_type: "week" }
    prefix  = SnapshotOptions.to_key_prefix(options)
    key_1   = "#{prefix}0/2013-03-19T15:04:50Z/mtoken.json.gz"
    key_2   = "#{prefix}1/2013-03-19T15:04:50Z/mtoken.json.gz"

myronmarston

defmodule Delorean.Parallel do
  def map(list, fun) do
    list
      |> Enum.map(fn(item) -> Task.async(fn -> fun.(item) end) end)
      |> Enum.map(&Task.await/1)
  end
end

myronmarston

# to get the name, you can use `instance_variable_get`:
tweet = double("Twitter::Tweet")
tweet.instance_variable_get(:@name) # => "Twitter::Tweet"

# that's clearly violating the public API, though. Another way is to pass it as a stub:
tweet = double("Twitter::Tweet", name: "Twitter::Tweet")
tweet.name # => "Twitter::Tweet"

# If you like that approach, you could create a new `named_double`
# helper method: