Selective testing

Selective testing {#selective-testing}

::: warning REQUIREMENTS

A generated project
A Tuist account and project

:::

To run tests selectively with your generated project, use the tuist test command. The command hashes your Xcode project the same way it does for warming the cache, and on success, it persists the hashes on to determine what has changed in future runs.

In future runs tuist test transparently uses the hashes to filter down the tests to run only the ones that have changed since the last successful test run.

For example, assuming the following dependency graph:

FeatureA has tests FeatureATests, and depends on Core
FeatureB has tests FeatureBTests, and depends on Core
Core has tests CoreTests

tuist test will behave as such:

Action	Description	Internal state
`tuist test` invocation	Runs the tests in `CoreTests`, `FeatureATests`, and `FeatureBTests`	The hashes of `FeatureATests`, `FeatureBTests` and `CoreTests` are persisted
`FeatureA` is updated	The developer modifies the code of a target	Same as before
`tuist test` invocation	Runs the tests in `FeatureATests` because it hash has changed	The new hash of `FeatureATests` is persisted
`Core` is updated	The developer modifies the code of a target	Same as before
`tuist test` invocation	Runs the tests in `CoreTests`, `FeatureATests`, and `FeatureBTests`	The new hash of `FeatureATests` `FeatureBTests`, and `CoreTests` are persisted

tuist test integrates directly with binary caching to use as many binaries from your local or remote storage to improve the build time when running your test suite. The combination of selective testing with binary caching can dramatically reduce the time it takes to run tests on your CI.

UI Tests {#ui-tests}

Tuist supports selective testing of UI tests. However, Tuist needs to know the destination in advance. Only if you specify the destination parameter, Tuist will run the UI tests selectively, such as:

tuist test --device 'iPhone 14 Pro'
# or
tuist test -- -destination 'name=iPhone 14 Pro'
# or
tuist test -- -destination 'id=SIMULATOR_ID'