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cupakromer / broken_session
Created Sep 30, 2014
Bundler binstubs + standalone problem
View broken_session
# With a clean project setup
$ bundle --binstubs --standalone
$ bundle binstubs rspec-core
$ cat bin/rspec
#!/usr/bin/env ruby
# This file was generated by Bundler.
View gist:68c6ad077d5d535211f4

Some suggested updates to the slides in These suggestions are based off of the array of built-in matchers that RSpec 3 provides ( As well as the composability / compounding features now available:

Slide 24

expect(influence.relevance).to (be <= 100).and (be >= 0)

You can also just make this a range matcher:

cupakromer / gist:234e5468586c5aa3daa3
Created Aug 4, 2014
Check raise error with backtrace
View gist:234e5468586c5aa3daa3
def capture_backtrace(with_error: StandardError, &action)
rescue with_error => e
# This fails if SocketError is not raised,
# or if the message doesn't match
it "raises a socket error reporting the address info" do
cupakromer / gist:fc5ccd67714c878dd5d8
Created Jul 25, 2014
Sample model spec using RSpec 3.0 and Ruby 2.x
View gist:fc5ccd67714c878dd5d8
require 'rails_helper'
RSpec.describe User, type: :model do
def build_valid_user(opts = {})
valid_opts = {
name: "Example User",
email: "",
password: "foobar",
password_confirmation: "foobar",
cupakromer / spec-domain-exportable_widget.rb
Created Jul 18, 2014
Trying out some new RSpec `shared_example` ideas
View spec-domain-exportable_widget.rb
require 'domain/exportable_widget'
require 'support/preconditions'
RSpec.describe ExportableWidget do
# We don't know yet if we will have multiple exportable objects, but this
# is simply the documentation of our intended shared protocol if we do later.
shared_examples_for "an exportable" do
required_attribute :exportable
View gist:ad3619347b4de978e9fa
# As far as I was aware, symbol-to-proc was supposed to be roughly equivalent to:
# { |v| v.send(self) }
# However, the following produces very odd results. Why?!?
[[3, 4], [5, 6], [3, 4], [5, 6]]
# => [[], [5], [3, 4], [5, 6]]
[[3, 4], [5, 6], [3, 4], [5, 6]]{ |x| x.first }
# => [3, 5, 3, 5]
cupakromer / gist:974c6fb9d0d6de3c2a6e
Created Jul 15, 2014
Various way to test for monkey patching with RSpec 3's `instance_double`
View gist:974c6fb9d0d6de3c2a6e
class Calculator
def reduce(operator)
fail "You shouldn't be calling this directly!"
def uses_a_duck_type(calculation)
View gist:5037f32312e75413e645

Command Line Tricks

  • !! Repeat Previous Command
  • !-1 Repeat Previous Command
  • !-2 Repeat 2nd Previous Command
  • !ps Execute Previous Command STARTING WITH ps
  • !^ First Argument From Previous Command
  • !:2 2nd Argument From Previous Command
  • !$ Last Argument From Previous Command
  • !!:$ Last Argument From Previous Command
View Gemfile
gem 'jekyll', '~> 2.0.0.alpha'
gem 'nokogiri'
gem 'redcarpet'
gem 'rouge'
cupakromer / gist:023278290dddebd785a6
Last active Aug 29, 2015
"class" methods in Ruby
View gist:023278290dddebd785a6
class Book
# This is a "class" method
def Book.catch_em_all
"I'm sorry, you can't do that Dave"
# This is also a "class" method, since "self" right now is the
# Class object instance for this "class"
def self.bind_it(spell)
"We're still working on binding books with spell."
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