[andresvillenas]

Summary

Fixes #25.

The administration client had no JavaScript test runner, so request building, validation and preview invalidation could only be checked by hand in a running admin. #22, #24 and #26 were all client-side bugs that the .NET tests couldn't catch.

Setup: Vitest with React Testing Library, jsdom and jest-dom matchers. All four are dev dependencies only.

• npm test runs src/**/*.test.tsx, which sit next to each component.
• The Kentico admin packages only run inside the Xperience admin, so vitest.config.mts points @kentico/xperience-admin-base and @kentico/xperience-admin-components at small test doubles in Client/test/kentico:
  • usePageCommand records every payload in pageCommandCalls and returns responses set per test with mockPageCommand. Like the real hook, execute keeps the same identity across renders.
  • The admin components (Dialog, Input, Select, DateTimeInput, …) render plain HTML with proper labels, so tests query by role and label text.
• The webpack build is unaffected: the bundle hash didn't change. The NuGet package still contains only Client/dist.

Tests (17):

• FormSubmissionRemovalComponent:
  • Preview sends no boundary. Export these first and Delete send the same filters, including the record limit ([Bug]: Export these first ignores Number of records limit #22) and the preview's upperSubmissionId ([Bug]: Advanced delete can remove submissions created after the preview #24).
  • The export starts the download.
  • Delete shows the snackbar and closes the dialog.
  • Delete is disabled until a preview exists.
  • Changing any of the four filters invalidates the preview.
  • Only the exact phrase DELETE enables Delete.
  • An invalid record limit is rejected without calling the server.
  • Server errors are shown in the dialog.
• FormCloneComponent:
  • The default name is loaded for the row's form, and Clone sends the trimmed name.
  • The display name limit is measured after trimming, like the server does ([Bug]: Client type check fails and is not run in CI #26).
  • Clone is disabled for a blank name.
  • An invalid row form ID shows an error without calling the server.
  • Server errors are shown.

CI and docs: CI runs npm test after npm run typecheck in the minimum-compatibility job. CONTRIBUTING.md and docs/Contributing-Setup.md now list both commands and explain the test doubles.

The Advanced export and Export selected dialogs are not covered yet. They can reuse the same test doubles.

Test plan

• The CI client steps pass from a clean npm ci: npm run typecheck, then npm test (17/17), then npm run build. The rebuilt dist matches the committed bundle.

• With each fixed bug put back temporarily, exactly the test aimed at it fails:

  Reintroduced bug	Failing test
  [Bug]: Export these first ignores Number of records limit #22: export sends numberOfRecords: null	previews without a boundary and uses the returned boundary for export and delete
  [Bug]: Advanced delete can remove submissions created after the preview #24: export/delete ignore the preview boundary	same test
  [Bug]: Client type check fails and is not run in CI #26: clone ignores the length limit	blocks names longer than the server's limit, measured after trimming

• No React act() warnings or console errors during the run.

• dotnet pack output contains no test files.

• npm audit reports 11 findings (fast-uri, qs, react-router, uuid). The same 11 exist on main; these dependencies add none. Out of scope here.