test(habits): cover pagination arithmetic, validator boundaries, and bulk-size limits

[thomasluizon]

Closes the remaining /prod-readiness tests-audit gaps for the habit-schedule query and the bulk-habit validators (Batch 7, api tests part 2). Tests only — no source change was required to make these testable.

GetHabitScheduleQueryValidator (edges, exact ValidationFailure)

• Negative Page → single failure on Page, code GreaterThanOrEqualValidator, attempted value asserted.
• PageSize above MaxPageSize and PageSize = 0 → single failure on PageSize, code InclusiveBetweenValidator, attempted value asserted.
• PageSize at MaxPageSize and Page at minimum (1) → no error (passing boundary).

GetHabitScheduleQueryHandler (pagination correctness)

• totalCount = 0 → TotalPages = 0, Page = 1, empty items.
• totalCount exactly divisible by PageSize → exact TotalPages.
• totalCount with +1 remainder → TotalPages rounds up and the last page holds the remainder.
• A page far beyond the last clamps to the last page (with its remainder item) and correct metadata — not an error, not empty.
• Search + frequency-unit filter combined with pagination returns the correctly filtered+paged subset with correct TotalCount/TotalPages/Page.

Bulk validators (boundary at configured max)

• BulkCreate / BulkDelete / BulkLog: a near-limit (MaxBulkOperationSize) payload validates; an over-limit payload is rejected with the exact configured-max message.

All assertions can fail if the behavior breaks (no rubber-stamps). Full Orbit.Application.Tests suite green (2772 passed).

Refs thomasluizon/orbit-ui-mobile#243

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[claude]

PR Review: #380 — test(habits): cover pagination arithmetic, validator boundaries, and bulk-size limits

Recommendation: APPROVE

Severity	Count
Critical	0
High	0
Medium	0
Low / Info	0

Scope

Test-only diff, 4 files, 215 insertions, no src/ changes:

• tests/Orbit.Application.Tests/Queries/Habits/GetHabitScheduleQueryHandlerTests.cs — 5 new tests covering pagination arithmetic (zero total, exact-divisible page count, remainder rounding, page-beyond-last clamping, combined search+frequency-filter+pagination)
• tests/Orbit.Application.Tests/Validators/BulkCommandValidatorTests.cs — exact-max/over-max boundary tests for bulk create/delete
• tests/Orbit.Application.Tests/Validators/BulkLogHabitsCommandValidatorTests.cs — over-max error message test
• tests/Orbit.Application.Tests/Validators/GetHabitScheduleQueryValidatorTests.cs — error-code/attempted-value assertions for Page/PageSize boundaries

Verification performed

Independently traced every new assertion against the production code it exercises:

• src/Orbit.Application/Habits/Queries/GetHabitScheduleQuery.cs:165-166,220-221,320-321 — confirmed totalPages = (int)Math.Ceiling((double)totalCount / request.PageSize) and page = Math.Max(1, Math.Min(request.Page, Math.Max(1, totalPages))) match all 4 new pagination-boundary tests, including the Page: 999 clamp-to-last-page case.
• src/Orbit.Application/Habits/Validators/GetHabitScheduleQueryValidator.cs:31-35 — confirmed RuleFor(q => q.Page).GreaterThanOrEqualTo(1) and RuleFor(q => q.PageSize).InclusiveBetween(1, AppConstants.MaxPageSize) produce exactly the "GreaterThanOrEqualValidator" / "InclusiveBetweenValidator" FluentValidation error codes asserted in the new tests.
• src/Orbit.Application/Habits/Validators/BulkCreateHabitsCommandValidator.cs:17-18, BulkDeleteHabitsCommandValidator.cs:17-18, BulkLogHabitsCommandValidator.cs:19-20 — confirmed the exact error message strings ("Cannot create more than {N} habits at once", "Cannot delete more than {N} habits at once", "Bulk log cannot exceed {N} items") match the new test assertions verbatim.
• AppConstants.MaxBulkOperationSize = 100, AppConstants.MaxPageSize = 200 — confirmed values are referenced (not hardcoded) in all new boundary tests, so tests stay correct if the constants change.

No dead code, no comment-policy violations, no security surface touched (no src/ changes), no DTO/contract surface touched, no i18n/FEATURES.md/DESIGN.md surface touched. Cross-repo dimensions (contract-aligner, mobile parity) are N/A — this PR adds only backend unit tests.

Deferred

• dotnet build / dotnet test — not run in this session per the CI-adaptation note (Build/Unit Tests/SonarCloud run as separate required checks on this PR). Substituted with a manual line-by-line trace of the pagination arithmetic and validator rules against the actual source, detailed above.