Achievable Status Fix Implementation Plan

For agentic workers: REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (- [ ]) syntax for tracking.

Goal: Fix determineStatuses so specs that are infeasible alongside achieved specs show as "unreachable" instead of falsely "achievable."

Architecture: Add a feasibility check in determineStatuses() after the upper bound check passes. Uses the existing checkWithS2 helper to LP-solve whether the spec can be achieved alongside the already-achieved set.

Tech Stack: TypeScript, Vitest, javascript-lp-solver

Task 1: Write failing test for the bug scenario

Files:

Modify: app/src/solver/__tests__/optimizer.test.ts
Step 1: Add test case for LCM being falsely marked achievable

Add to the determineStatuses describe block:

it('marks spec as unreachable when infeasible alongside achieved specs due to credit sharing', () => {
  // Bug scenario: CRF+STR achieved, LCM has 10 credit upper bound but
  // shared courses (spr3, fall3) are consumed by CRF/STR
  const selectedCourses = [
    'spr1-collaboration',              // LCM, MGT
    'spr2-financial-services',         // BNK, CRF, FIN, FIM
    'spr3-mergers-acquisitions',       // CRF, FIN, LCM, STR(S1)
    'spr4-foundations-entrepreneurship', // ENT, MGT, STR(S1)
    'spr5-corporate-finance',          // CRF, FIN
    'sum1-global-immersion',           // GLB
    'sum2-business-drivers',           // STR(S1)
    'sum3-valuation',                  // BNK, CRF, FIN, FIM
    'fall1-managing-change',           // LCM, MGT, STR(S2)
    'fall2-decision-models',           // MGT, MTO
    'fall3-corporate-governance',      // LCM, MGT, SBI, STR(S1)
    'fall4-game-theory',               // MGT, STR(S1)
  ];
  const achieved = ['CRF', 'STR', 'MGT'];
  const statuses = determineStatuses(selectedCourses, [], achieved);

  // LCM upper bound is 10 (>= 9) but infeasible alongside CRF+STR+MGT
  expect(statuses['LCM']).toBe('unreachable');
});

Step 2: Run the test to verify it fails

Run: cd /home/bill/dev/emba-course-solver/app && npx vitest run src/solver/__tests__/optimizer.test.ts -t "marks spec as unreachable when infeasible alongside achieved specs"

Expected: FAIL — statuses['LCM'] is 'achievable' but expected 'unreachable'

Task 2: Implement the feasibility check in determineStatuses

Files:

Modify: app/src/solver/optimizer.ts:146-185
Step 3: Add feasibility check after the upper bound gate

In app/src/solver/optimizer.ts, in the determineStatuses function, replace:

    statuses[spec.id] = 'achievable';

(line 181) with:

    // Verify spec is actually feasible alongside already-achieved specs
    const testSet = [...achieved, spec.id];
    const feasResult = checkWithS2(selectedCourseIds, testSet);
    statuses[spec.id] = feasResult.feasible ? 'achievable' : 'unreachable';

Step 4: Run the failing test to verify it now passes

Run: cd /home/bill/dev/emba-course-solver/app && npx vitest run src/solver/__tests__/optimizer.test.ts -t "marks spec as unreachable when infeasible alongside achieved specs"

Expected: PASS

Step 5: Run the full test suite to check for regressions

Run: cd /home/bill/dev/emba-course-solver/app && npx vitest run

Expected: All tests pass

Step 6: Commit

cd /home/bill/dev/emba-course-solver
git add app/src/solver/optimizer.ts app/src/solver/__tests__/optimizer.test.ts
git commit -m "fix: mark specs as unreachable when infeasible alongside achieved specs

determineStatuses() was marking specs as 'achievable' based solely on
per-specialization upper bounds, ignoring credit sharing with achieved
specs. Now performs an LP feasibility check to verify the spec can
actually be achieved alongside the current achieved set."

3.9 KiB Raw Blame History

Achievable Status Fix Implementation Plan

Task 1: Write failing test for the bug scenario

Task 2: Implement the feasibility check in determineStatuses

3.9 KiB

Raw Blame History