test: make the LoadedTabPage streak test actually assert

[brian-smith-tcril]

Summary

Make the shows streak celebration modal case in tab-page/LoadedTabPage.test.jsx actually assert. It could not fail: the StreakModal mock rendered a bare div whatever its props, and LoadedTabPage renders StreakModal on every render, open or closed; and its fixture set celebrations on the courseware metadata factory, while the component has read celebrations from courseHomeMeta since AA-1018 (2022), which the test store fills from a separate factory with celebrations: null. Removing celebrations from the fixture left the test green. Test-only; LoadedTabPage.tsx is untouched. Stacked on #2106 as the stack top; below B2 (#2085), which rewrites this suite's data source and should land on a case that checks something. Part of #1946 as test hygiene on code the migration touches. Closes #2107.

What changed

• The fixture goes on the courseHomeMetadata factory, through the initializeTestStore option the suite's staff case already uses, so the streak reaches the model the component reads, camel-cased by the real normalizer.
• The modal is no longer mocked. Closed, StreakCelebrationModal renders nothing; open, it renders a dialog titled with the streak length. The case asserts a dialog reading "3 day streak" is on the page. Rendering it costs what its own suite pays: the analytics module mocked and an act wrapper around the render.
• renders correctly asserts the contrast: no dialog on the default fixture. A modal that is always open cannot satisfy the streak case's assertion.

Testing

npm run types and npm run lint clean; LoadedTabPage.test.jsx 3/3 with no console output. Negative checks on this layer: removing celebrations from the fixture fails the streak case (no element with role dialog); forcing the modal open in the component fails the contrast (a dialog titled "null day streak"). The full suite was not run for a one-file test change.

Provenance

The mock has been unconditional since the case was written in #354 (2021-02-22). The fixture stopped reaching the component in AA-1018 (3fe5bb1, 2022-01-14), which moved LoadedTabPage's read to courseHomeMeta and gave the test store its own courseHomeMetadata factory. Found while planning B2 (#2085), which rewrites how this suite gets its data; split out as its own layer, like #2078 / #2079 and #2100 / #2101, so B2's diff to the suite is only the data-source swap.

Decisions

Full decision log

Decisions — make the LoadedTabPage streak test actually assert (#2107)

Test-only layer between #2103 (PR #2106) and B2 (#2085). Entries 1 and 2 were
settled while reviewing the #2085 plan; the rest landed with the code.

1. A layer of its own, below B2. B2 rewrites how LoadedTabPage.test.jsx
   gets its data (the query instead of the store), so it would have had to
   touch this case anyway, and the first draft of the B2 plan fixed it there.
   Rejected in review for the Make the courseware redirect-rule tests actually assert: un-awaited waitFor and unwired mocks from #1501 #2078 / Make the useIsCourseLoaded tests actually assert: replaced mocks and unsettled checks from #2071 #2100 shape: a small issue and a tiny
   test: layer first, so B2's diff to the suite is only the data-source
   swap and the repair of a 2021 test is reviewed as what it is. It sits on
   Stop the progress tab data refetching from components under the tab #2103 because that is the stack top; nothing in it depends on Stop the progress tab data refetching from components under the tab #2103.

2. Two defects, either of which alone keeps the case green.

   • The mock rendered unconditionally. StreakCelebrationModal was
     mocked as a component returning <div data-testid="StreakModal" />
     whatever its props, and LoadedTabPage always renders StreakModal
     (LoadedTabPage.tsx:71-77), open or closed. "The mock is in the
     document" is true on every render. So since the case was written
     (2525805, [AA-304] Create three day streak celebration #354, 2021-02-22).
   • The fixture never reached the component. The case built the
     courseware metadata factory with celebrations, but LoadedTabPage has
     read celebrations from courseHomeMeta since 3fe5bb1 (AA-1018,
     2022-01-14), and initializeTestStore fills that model from a separate
     courseHomeMetadata factory built with celebrations: null
     (buildSimpleCourseAndSequenceMetadata, sequenceMetadata.factory.js).
     The case was not updated then. b3d3366 (Updated frontend-build to v12 #962, 2023) only reformatted
     the mock for a lint rule.

   Removing celebrations from the fixture left the case green, on this
   layer's base with no other change.

3. The fixture goes on the courseHomeMetadata factory, through the
   initializeTestStore option. initializeTestStore({ courseHomeMetadata })
   is the shape the suite's staff case already uses
   (original_user_is_staff: true), and the store fills courseHomeMeta
   from the mocked course_metadata endpoint through the real normalizer, so
   streak_length_to_celebrate arrives camel-cased exactly as production
   data does. The course id comes from getTestStoreIds(testStore) rather
   than a hand-built courseMetadata, since the case no longer builds one.

4. The modal is not mocked; the case asserts on the dialog. A first
   version kept a mock and made it a jest.fn component
   (UnitSuspense.test.jsx:20-21's shape), asserting on the props
   LoadedTabPage passed it — isStreakCelebrationOpen: true,
   streakLengthToCelebrate: 3. Rejected in review: that tests that
   LoadedTabPage hands a stub an open flag, not that anything is shown,
   which is what the case is named for. The real StreakCelebrationModal
   returns null when closed (StreakCelebrationModal.jsx:117-119) and
   renders a Paragon ModalDialog titled
   ${streakLengthToCelebrate} day streak when open (:143-161), so the
   case now asserts getByRole('dialog') has text 3 day streak: both the
   open flag and the length flow through the real component to what a
   learner sees. Rendering it costs what its own suite pays
   (StreakCelebrationModal.test.jsx:18-19,56): jest.mock('@edx/frontend-platform/analytics'),
   because opening fires recordStreakCelebration → sendTrackEvent, and an
   act wrapper around the render for the modal's effects. Its own
   useModel('courseHomeMeta') read (org, username) is served by the
   same store the fixture fills; its discount effect is skipped because
   streakDiscountCouponEnabled is null on the default fixture.

5. renders correctly asserts the contrast. On the default fixture
   (celebrations: null) there is no dialog on the page
   (queryByRole('dialog') is null). Without it the streak case's assertion
   could be satisfied by a modal that is always open — the mirror of
   defect 1. It also pins the !! coercion on the prop
   (LoadedTabPage.tsx:75): forcing the prop to true in the component
   renders a dialog titled "null day streak" and fails this case.

6. Test-only, one file. LoadedTabPage.tsx is untouched; the diff is
   src/tab-page/LoadedTabPage.test.jsx alone (10 insertions, 8 deletions).
   Suite 3/3 with no console output; npm run lint and npm run types
   clean. Negative checks on this layer: removing celebrations from the
   fixture fails shows streak celebration modal (no element with role
   dialog); replacing !!isStreakCelebrationOpen with a bare
   isStreakCelebrationOpen on the StreakModal prop fails renders
   correctly. The full suite was not run for a one-file test change.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.95%. Comparing base (8ffa5fe) to head (d908d76).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2108   +/-   ##
=======================================
  Coverage   93.95%   93.95%           
=======================================
  Files         367      367           
  Lines        5939     5939           
  Branches     1435     1435           
=======================================
  Hits         5580     5580           
  Misses        345      345           
  Partials       14       14           

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