Model SNAP student employment & training and work incentive placement exemptions

[hua7450]

Summary

Models the two SNAP higher-education student exemptions that turn on being placed in or enrolled in an institution of higher education through an employment-and-training or work-incentive program. Both were previously flagged "Not modeled" in is_snap_ineligible_student.

Closes #8750

Regulatory authority

Exemption	Statute	Regulation
Exception 3 — placed through an employment & training program (WIOA Title I, a SNAP E&T program limited to career/technical or remedial coursework, the Trade Act §236, or a state/local E&T program)	7 USC 2015(e)(3)	7 CFR 273.5(b)(11)
Exception 7 — enrolled as a result of participation in a title-IV work incentive program (JOBS / its TANF-work-program successor)	7 USC 2015(e)(7)	7 CFR 273.5(b)(4)

Citation note: the SNAP student TANF-receipt exemption is (b)(3) / (e)(6) — a separate provision — and is already modeled via tanf_person > 0. The two exemptions here are (b)(11)/(e)(3) and (b)(4)/(e)(7).

What changed

Variable	Entity / Period	Role
is_snap_employment_training_student (new)	Person / YEAR	Bare input for Exception 3. (b)(11) / (e)(3).
is_snap_work_incentive_student (new)	Person / YEAR	Bare input for Exception 7. (b)(4) / (e)(7).
is_snap_employment_training_or_work_incentive_student (new)	Person / YEAR	Formula OR of the two inputs — a single override point for partners.
is_snap_ineligible_student (modified)	Person / YEAR	Consumes the combined variable; the two "Not modeled" stubs are removed.
meets_snap_parent_exception (fix)	Person / YEAR	Corrected a malformed reference (a missing comma had concatenated its two URLs into one string).

is_snap_employment_training_student ──┐  (e)(3)/(b)(11)
                                      ├─► is_snap_employment_training_or_work_incentive_student ──► is_snap_ineligible_student
is_snap_work_incentive_student      ──┘  (e)(7)/(b)(4)

Design notes

• Faithful to the statute's causal requirement. Both exemptions require the school enrollment to come through the program, not mere participation/enrollment. Each input's documentation states this explicitly, so a screener maps only the affirmative "placed-through-program" fact.
• One input per statutory provision (distinct citations preserved), plus a combined formula variable so a partner can override a single variable for the whole placement exemption, or set the two granular inputs for citation-precise data.
• Pure inputs. The two inputs have no formula/defined_for and default to False; the half-time-or-more higher-education gate stays on the consumer (is_snap_ineligible_student is defined_for = "is_snap_higher_ed_student").
• Non-breaking. Default-False inputs leave is_snap_ineligible_student unchanged everywhere until a data source populates them, so existing behavior and partner contract tests are unaffected.

Partner context

An API partner (MyFriendBen) currently overrides is_snap_ineligible_student directly. With this change they can instead feed inputs — either overriding is_snap_employment_training_or_work_incentive_student at one point, or mapping their student_job_training_program flag to is_snap_employment_training_student.

Tests

• New unit test for the combined variable — 4 cases (neither / E&T only / work-incentive only / both).
• Integration flow-through in is_snap_ineligible_student.yaml: E&T placement, work-incentive placement, plus the previously-untested exemptions (age 50+, disability, 20 hours/week, work-study) so every modeled exemption is now exercised end-to-end.
• Input-purity tests (test_input_variable_definitions.py) confirm the two new inputs are pure data inputs.

Test plan

• SNAP student YAML tests pass (44 cases)
• Input-purity + SNAP-student-TANF core tests pass
• CI passes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (2615e68) to head (a553313).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #8793   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            8         5    -3     
  Lines          104        65   -39     
=========================================
- Hits           104        65   -39     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[PavelMakarchuk]

Approve ✅

Verified against the verbatim 7 CFR 273.5(b) and 7 USC 2015(e) text — this is a faithful adoption of the enacted federal law:

• is_snap_employment_training_student → 273.5(b)(11) / 2015(e)(3) (E&T / WIOA / Trade Act §236 / state-local placement) ✅
• is_snap_work_incentive_student → 273.5(b)(4) / 2015(e)(7) (title-IV work-incentive) ✅
• The separate TANF-receipt exception (b)(3)/(e)(6) is correctly left as tanf_person — not conflated.

Citations aren't swapped, the exemption correctly removes ineligibility (~(… | exception)), nothing is reinvented, and the code/test/reference checks are clean (full truth-table coverage). The one nuance — CFR still names the repealed JTPA/JOBS while the statute names WIOA/generic successors — is handled correctly by using the current WIOA framing.

Minor, non-blocking follow-ups (optional): add the 7 CFR 273.5(b) half to is_snap_ineligible_student's reference, and a downstream test asserting the exemption flips a SNAP eligibility outcome.

🤖 Review generated with Claude Code