[ci skip] document test suite

docs/development/testing.md

@@ -0,0 +1,36 @@
+# Dokku test suite
+
+Dokku now has a full test suite to assist in quick iterating development. These tests include a linter using [shellcheck](https://github.com/koalaman/shellcheck), functional unit tests using the [bats testing framework](https://github.com/sstephenson/bats), and a deployment suite of example apps that use the most popular languages and frameworks.
+
+Bats tests can be found here:
+  ```
+  tests/unit/*.bats
+  ```
+
+Example apps can be found here:
+  ```
+  tests/apps/
+  ```
+
+### Executing tests locally
+
+- Setup dokku in a [vagrant vm](http://progrium.viewdocs.io/dokku/getting-started/install/vagrant)
+- Test setup and execution
+
+  ```shell
+  $ vagrant ssh
+  $ sudo su -
+  $ cd ~/dokku
+  $ make ci-dependencies setup-deploy-tests
+  $ make test  # run the entire test suite (linter, bats tests, and app deployment tests)
+  $
+  $ make lint  # linter
+  $ make unit-tests  # bats tests
+  $ make deploy-tests  # app deployment tests
+  ```
+- Additionally you may run a specific app deployment tests with a target similar to:
+
+  ```shell
+  make deploy-test-nodejs-express
+  ```
+- For a full list of test make targets check out `tests.mk` in the root of the dokku repository.