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LWCIntermediatejesttestingunit-tests

Architect LWC testing with Jest and sfdx-lwc-jest

Real World Scenario

CI pipeline lacks LWC tests; regressions ship when wire adapters refactored.

Expected Answer

• Jest tests for public @api behavior and event firing • Mock @salesforce modules: apex, schema, uiRecordApi, labels • Test error and loading states not only happy path • Snapshot tests sparingly—prefer behavior assertions • Coverage gate on lwc/js files in pull requests • Integration tests in Playwright for critical user journeys supplement Jest • Test accessibility with jest-axe plugin

Follow-Up Questions & Answers

Click to expand — each follow-up includes a direct, interview-ready answer

Direct answer: Jest tests for public @api behavior and event firing Also consider: Mock @salesforce modules: apex, schema, uiRecordApi, labels In practice: Test error and loading states not only happy path Balance speed of delivery with maintainability.

Architect Perspective

LWC unit tests are fast feedback—architects mandate tests for components with Apex or LMS integration.