Update CONTRIBUTING.md

* Default process
* Test suite best practices

CONTRIBUTING.md

@@ -1 +1,38 @@
-To get started, <a href="http://www.clahub.com/agreements/jeremytregunna/ruby-trello">sign the Contributor License Agreement</a>.
+## Contributing
+
+1. To get started, please [sign the CLA]
+2. Fork the repository
+3. Run the tests.  We only accept pull request with a passing test
+   suite, so make sure you're starting from a clean slate: `bundle &&
+rake`
+4. Create a new branch for your new adjustments:
+   `features/my-new-feature`
+4. Add a test that addresses each code change (note: refactors and
+   documentation, do not require new tests).
+5. Run the test suite to make sure it's still green (passing): `bundle
+   && rake`
+6. Push the your branch to your fork, and submit a pull request
+
+[sign the CLA]: http://www.clahub.com/agreements/jeremytregunna/ruby-trello
+
+## Guides
+
+#### Test Suite
+
+For common best practices, please follow the guides found at
+http://betterspecs.org
+
+Let's highlight a few important patterns:
+
+* Use `expect` syntax over the deprecated `should` syntax (http://betterspecs.org#expect)
+* Use `allow(object).to receive(:method_name)` over the deprecated `object.stub(:method_name)` to define a stub
+* Use `expect(object).to receive(:method_name)` over the deprecated `object.should_receive(:method_name)` to define a stubbed expectation
+* Use `let` blocks over `@instance` variables to persist objects/values (http://betterspecs.org/#let)
+* Use `context` to control permutations and DRY-up duplicate stubs, mocks and override persistant objects (http://betterspecs.org/#contexts)
+* Place stubs into `before` blocks and not in the expectation block
+* Do *not* place expectations into `before` or `after` blocks
+* Utilize RSpec's support for predicate methods: `expect(object.valid?).to be(true)` should be `expect(object).to be_valid`
+
+**Additional Resources**
+
+RSpec Design Patterns Workshop at RailsConf 2014: https://youtu.be/d2gL6CYaYwQ