# Testing
 
 This document contains the Moby code testing guidelines. It should answer any 
 questions you may have as an aspiring Moby contributor.
 
 ## Test suites
 
 Moby has two test suites (and one legacy test suite):
 
 * Unit tests - use standard `go test` and
   [testify](https://github.com/stretchr/testify) assertions. They are located in
   the package they test. Unit tests should be fast and test only their own 
   package.
 * API integration tests - use standard `go test` and
   [testify](https://github.com/stretchr/testify) assertions. They are located in
   `./integration/<component>` directories, where `component` is: container,
   image, volume, etc. These tests perform HTTP requests to an API endpoint and
   check the HTTP response and daemon state after the call.
 
 The legacy test suite `integration-cli/` is deprecated. No new tests will be 
 added to this suite. Any tests in this suite which require updates should be 
 ported to either the unit test suite or the new API integration test suite.
 
 ## Writing new tests
 
 Most code changes will fall into one of the following categories.
 
 ### Writing tests for new features
 
 New code should be covered by unit tests. If the code is difficult to test with
 a unit tests then that is a good sign that it should be refactored to make it
 easier to reuse and maintain. Consider accepting unexported interfaces instead
 of structs so that fakes can be provided for dependencies.
 
 If the new feature includes a completely new API endpoint then a new API 
 integration test should be added to cover the success case of that endpoint.
 
 If the new feature does not include a completely new API endpoint consider 
 adding the new API fields to the existing test for that endpoint. A new 
 integration test should **not** be added for every new API field or API error 
 case. Error cases should be handled by unit tests.
 
 ### Writing tests for bug fixes
 
 Bugs fixes should include a unit test case which exercises the bug.
 
 A bug fix may also include new assertions in an existing integration tests for the
 API endpoint.
 
 ## Running tests
 
 To run the unit test suite:
 
 ```
 make test-unit
 ```
 
 or `hack/test/unit` from inside a `BINDDIR=. make shell` container or properly
 configured environment.
 
 The following environment variables may be used to run a subset of tests:
 
 * `TESTDIRS` - paths to directories to be tested, defaults to `./...`
 * `TESTFLAGS` - flags passed to `go test`, to run tests which match a pattern
   use `TESTFLAGS="-test.run TestNameOrPrefix"`
 
 To run the integration test suite:
 
 ```
 make test-integration
 ```