The following guidelines summarize the testing policy for docker/cli.
All code changes should have unit test coverage.
Error cases should be tested with unit tests.
Bug fixes should be covered by new unit tests or additional assertions in existing unit tests.
The unit test suite follows the standard Go testing convention. Tests are located in the package directory in _test.go files.
Unit tests should be named using the convention:
Test<Function Name><Test Case Name>
Table tests should be used where appropriate, but may not be appropriate in all cases.
Assertions should be made using testify/assert and test requirements should be verified using testify/require.
Fakes, and testing utilities can be found in internal/test and gotestyourself.
The end-to-end test suite tests a cli binary against a real API backend.
Each feature (subcommand) should have a single end-to-end test for the success case. The test should include all (or most) flags/options supported by that feature.
In some rare cases a couple additional end-to-end tests may be written for a sufficiently complex and critical feature (ex: container run, service create, service update, and docker build may have ~3-5 cases each).
In some rare cases a sufficiently critical error paths may have a single end-to-end test case.
In all other cases the behaviour should be covered by unit tests.
If a code change adds a new flag, that flag should be added to the existing “success case” end-to-end test.
If a code change fixes a bug, that bug fix should be covered either by adding assertions to the existing end-to-end test, or with one or more unit test.
The end-to-end test suite is located in ./e2e. Each directory in e2e corresponds to a directory in cli/command and contains the tests for that subcommand. Files in each directory should be named <command>_test.go where command is the basename of the command (ex: the test for docker stack deploy is found in e2e/stack/deploy_test.go).
Tests should be named using the convention:
Test<Command Basename>[<Test Case Name>]
where the test case name is only required when there are multiple test cases for a single command.
End-to-end test should run the docker binary using gotestyourself/icmd and make assertions about the exit code, stdout, stderr, and local file system.
Any Docker image or registry operations should use registry:5000/<image name> to communicate with the local instance of the Docker registry. To load additional fixture images to the registry see scripts/test/e2e/run.