suites/
|---- public-api/
      |---- captureMessage/
            |---- test.ts [assertions]
            |---- scenario.ts [Sentry initialization and test subject]
      |---- customTest/
            |---- test.ts [assertions]
            |---- scenario_1.ts [optional extra test scenario]
            |---- scenario_2.ts [optional extra test scenario]
            |---- server_with_mongo.ts [optional custom server]
            |---- server_with_postgres.ts [optional custom server]
utils/
|---- defaults/
      |---- server.ts [default Express server configuration]

The tests are grouped by their scopes, such as public-api or tracing. In every group of tests, there are multiple folders containing test scenarios and assertions.

Tests run on Express servers (a server instance per test). By default, a simple server template inside utils/defaults/server.ts is used. Every server instance runs on a different port.

A custom server configuration can be used, supplying a script that exports a valid express server instance as default. runServer utility function accepts an optional serverPath argument for this purpose.

scenario.ts contains the initialization logic and the test subject. By default, {TEST_DIR}/scenario.ts is used, but runServer also accepts an optional scenarioPath argument for non-standard usage.

test.ts is required for each test case, and contains the server runner logic, request interceptors for Sentry requests, and assertions. Test server, interceptors and assertions are all run on the same Jest thread.

utils/ contains helpers and Sentry-specific assertions that can be used in (test.ts).

TestEnv class contains methods to create and execute requests on a test server instance. TestEnv.init() which starts a test server and returns a TestEnv instance must be called by each test. The test server is automatically shut down after each test, if a data collection helper method such as getEnvelopeRequest and getAPIResponse is used. Tests that do not use those helper methods will need to end the server manually.

TestEnv instance has two public properties: url and server. The url property is the base URL for the server. The http.Server instance is used to finish the server eventually.

Nock interceptors are internally used to capture envelope requests by getEnvelopeRequest and getMultipleEnvelopeRequest helpers. After capturing required requests, the interceptors are removed. Nock can manually be used inside the test cases to intercept requests but should be removed before the test ends, as not to cause flakiness.

Tests can be run locally with:

yarn test

To run tests with Jest's watch mode:

yarn test:watch

To filter tests by their title:

yarn test -t "set different properties of a scope"

You can refer to Jest documentation for other CLI options.