Align the catalogue tests with the canonical cohort routes

[alexeygrigorev]

Goal

Unblock the Django release gate: since #320 the catalogue template emits the canonical cohort routes, but three catalogue tests still expect the legacy generic two-segment shape. The django job has been unable to run to completion on main since #320 landed (every run died earlier at the quality gate, fixed by #341), so these stale expectations surfaced only now, as the only remaining red gate.

Evidence

Main run 34189057638 (87fd3f4): quality, container, playwright and screenshots all pass; django fails with 2 failures + 1 error, all in courses/tests/test_course_list_ordering.py:

• test_catalogue_has_one_family_card_for_multiple_cohorts: asserts the literal /courses/catalogue-course/2026, but the card renders /courses/catalogue-course/cohorts/2026.
• test_featured_course_is_an_exact_homepage_catalog_cohort: expects href="/courses/de-zoomcamp/2026", page renders the /cohorts/ shape.
• test_active_and_finished_cards_link_to_their_cohort_routes: the course_card_html helper (courses/tests/course_list_base.py) locates the card via reverse("course", ...) and fails with ValueError: substring not found.

Root cause: #320 renamed the catalogue template's edition URL from {% url 'course' %} to {% url 'cohort' %}. Per the frozen route map (_docs/compatibility/shared-curriculum-route-aliases.json, decided 2026-09-07, owner PM #320), /courses/<family>/cohorts/<identifier> (route name cohort) is canonical; the generic two-segment shape remains only as a legacy alias. The product is aligned with the spec; the three tests plus the two course_list_base.py helpers still assert the legacy shape.

Scope

• Test-only: switch the two helpers and three tests in courses/tests/test_course_list_ordering.py / courses/tests/course_list_base.py to the canonical cohort route (reverse with cohort_identifier, matching the file's post-Share current Zoomcamp curriculum across live and self-paced cohorts with GitHub archives #320 style).
• No product, template, URL or spec change.

Non-goals

• No change to the route table, aliases, or any canonical route decision.
• No broader test rewrite beyond the stale route expectations.

Acceptance criteria

• uv run python manage.py test courses.tests.test_course_list_ordering --settings=website.settings.test passes.
• The complete local Django suite passes (mirrors the CI django job).
• make lint, make format-check, make typecheck stay green.
• The next main CI run is gate-green end to end (quality, django, playwright, container).

[alexeygrigorev]

Scope correction and handoff notes, after a full local reproduction on 87fd3f4 and a verified partial fix.

Corrected failure inventory for the django job (run 34189057638)

The failures split into two independent classes:

1. Route-shape staleness (this issue). Share current Zoomcamp curriculum across live and self-paced cohorts with GitHub archives #320 switched the catalogue template's edition links to the canonical cohort route and made cohort_identifier a required kwarg on the cohort-namespaced patterns, but several tests still reverse or assert the legacy generic shape:

   • courses/tests/test_course_list_ordering.py: three tests (2 failures + 1 error) plus the course_card_html / course_archive_row_html helpers in courses/tests/course_list_base.py.
   • courses/tests/test_homework_optional_fields.py (homework_url), courses/tests/test_local_question_seed.py, courses/tests/test_local_project_review_seed.py, core/tests/test_course_platform_vendor_assets.py: reverse("cohort_homework" / "cohort_project" / "cohort_project_list" / "cohort_projects_eval" / "cohort_projects_eval_submit") called without the now-required cohort_identifier. Their fixtures also predate the family+identifier scheme (bare Cohort.objects.create without identifier or family), so the fix is fixture redesign, not just kwarg insertion.

2. The archive_commit_sha NOT NULL setup errors: owned by Restore the green release matrix: Course creation hits NOT NULL on courses_course.archive_commit_sha #345, not this issue.

Verified partial fix, pushed as branch issue-347 (a693e82)

• The two base helpers and the three ordering expectations now use reverse("cohort", ...).
• The homepage expectation in test_featured_course_is_an_exact_homepage_catalog_cohort keeps the legacy alias, which is still what the homepage renders today; note the homepage therefore links the legacy alias while the catalogue links canonical, which is worth a product look once the gate is green.
• Locally green: courses.tests.test_course_list_ordering + courses.tests.test_course_list_metadata, make lint, make format-check.

If the #345 session prefers to absorb the route fixes into its pass, merging branch issue-347 as-is covers the ordering/base half; the homework/seed/vendor helper migration needs the fixture redesign sketched above. I am not merging to main to stay out of #345's way.

[alexeygrigorev]

Scope correction and handoff notes, after a full local reproduction on 87fd3f4 and a verified partial fix.

Corrected failure inventory for the django job (run 34189057638)

The failures split into two independent classes:

1. Route-shape staleness (this issue). Share current Zoomcamp curriculum across live and self-paced cohorts with GitHub archives #320 switched the catalogue template's edition links to the canonical cohort route and made cohort_identifier a required kwarg on the cohort-namespaced patterns, but several tests still reverse or assert the legacy generic shape:

   • courses/tests/test_course_list_ordering.py: three tests (2 failures + 1 error) plus the course_card_html / course_archive_row_html helpers in courses/tests/course_list_base.py.
   • courses/tests/test_homework_optional_fields.py (homework_url), courses/tests/test_local_question_seed.py, courses/tests/test_local_project_review_seed.py, core/tests/test_course_platform_vendor_assets.py: reverse("cohort_homework" / "cohort_project" / "cohort_project_list" / "cohort_projects_eval" / "cohort_projects_eval_submit") called without the now-required cohort_identifier. Their fixtures also predate the family+identifier scheme (bare Cohort.objects.create without identifier or family), so the fix is fixture redesign, not just kwarg insertion.

2. The archive_commit_sha NOT NULL setup errors: owned by Restore the green release matrix: Course creation hits NOT NULL on courses_course.archive_commit_sha #345, not this issue.

Verified partial fix, pushed as branch issue-347 (a693e82)

• The two base helpers and the three ordering expectations now use reverse("cohort", ...).
• The homepage expectation in test_featured_course_is_an_exact_homepage_catalog_cohort keeps the legacy alias, which is still what the homepage renders today; note the homepage therefore links the legacy alias while the catalogue links canonical, which is worth a product look once the gate is green.
• Locally green: courses.tests.test_course_list_ordering + courses.tests.test_course_list_metadata, make lint, make format-check.

If the #345 session prefers to absorb the route fixes into its pass, merging branch issue-347 as-is covers the ordering/base half; the homework/seed/vendor helper migration needs the fixture redesign sketched above. I am not merging to main to stay out of #345's way.