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Lower of cost and net realizable value: prior carrying default · case 01

Newly counted items show a huge positive adjustment as if they were previously carried at zero.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

A missing prior carrying value defaults to zero instead of original cost.

VERIFIED REPAIR

Default the prior carrying value to original cost.

Unsuccessful approach: Defaulting to the current NRV makes every first-time write-down disappear.

Case contract

Input {items:[{sku,qty,cost,price,complete,sell_bp,group}], prior:{sku:carrying unit}}. NRV = price - complete - round-half-up(price*sell_bp/10000), floored at 0. Carrying unit = min(original cost, NRV). Adjustment = qty*(carrying - prior carrying), prior defaulting to original cost (reversals are thereby capped at cost). Group check: write-down per group = max(0, sum qty*cost - sum qty*NRV). Return {items:[[sku,carry,adj]], group_writedown}.

Why this case matters

Inventory valuation and cost-of-goods decisions depend on this rule.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    res = []
    groups = {}
    for it in x['items']:
        sell = (it['price'] * it['sell_bp'] + 5000) // 10000
        nrv = it['price'] - it['complete'] - sell
        if nrv < 0:
            nrv = 0
        carry = min(it['cost'], nrv)
        prior = x['prior'].get(it['sku'], 0)
        res.append([it['sku'], carry, it['qty'] * (carry - prior)])
        g = groups.setdefault(it['group'], [0, 0])
        g[0] += it['qty'] * it['cost']
        g[1] += it['qty'] * nrv
    gw = {k: max(0, v[0] - v[1]) for k, v in sorted(groups.items())}
    return {'items': res, 'group_writedown': gw}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1001, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 251, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 601}}, {'items': [['D', 800, 796]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 601, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1002, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 252, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 602}}, {'items': [['D', 800, 792]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 602, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1003, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 253, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 603}}, {'items': [['D', 800, 788]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 603, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1004, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 254, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 604}}, {'items': [['D', 800, 784]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 604, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1005, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 889, -555]], 'group_writedown': {'g1': 555}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 255, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 605}}, {'items': [['D', 800, 780]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 605, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
write down{'group_writedown': {'g1': 550}, 'items': [['A', 890, 4450]]}{'group_writedown': {'g1': 550}, 'items': [['A', 890, -550]]}Failed
no write down{'group_writedown': {'g1': 0}, 'items': [['B', 500, 1000]]}{'group_writedown': {'g1': 0}, 'items': [['B', 500, 0]]}Failed
negative nrv{'group_writedown': {'g2': 1200}, 'items': [['C', 0, 0]]}{'group_writedown': {'g2': 1200}, 'items': [['C', 0, -1200]]}Failed
reversal capped{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}Passed
partial reversal{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}Passed
group offset{'group_writedown': {'g3': 0}, 'items': [['F', 700, 700], ['G', 200, 200]]}{'group_writedown': {'g3': 0}, 'items': [['F', 700, -300], ['G', 200, 0]]}Failed
group loss{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 200]]}{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 0]]}Failed
costly completion{'group_writedown': {'g5': 250}, 'items': [['K', 50, 50]]}{'group_writedown': {'g5': 250}, 'items': [['K', 50, -250]]}Failed

SHA-256 / 310a06fa458cb5276d8097f759cfcd19c21f89e1d2cabe352187db7b1158bc48

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    res = []
    groups = {}
    for it in x['items']:
        sell = (it['price'] * it['sell_bp'] + 5000) // 10000
        nrv = it['price'] - it['complete'] - sell
        if nrv < 0:
            nrv = 0
        carry = min(it['cost'], nrv)
        prior = x['prior'].get(it['sku'], carry)
        res.append([it['sku'], carry, it['qty'] * (carry - prior)])
        g = groups.setdefault(it['group'], [0, 0])
        g[0] += it['qty'] * it['cost']
        g[1] += it['qty'] * nrv
    gw = {k: max(0, v[0] - v[1]) for k, v in sorted(groups.items())}
    return {'items': res, 'group_writedown': gw}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1001, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 251, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 601}}, {'items': [['D', 800, 796]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 601, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1002, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 252, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 602}}, {'items': [['D', 800, 792]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 602, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1003, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 253, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 603}}, {'items': [['D', 800, 788]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 603, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1004, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 254, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 604}}, {'items': [['D', 800, 784]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 604, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1005, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 889, -555]], 'group_writedown': {'g1': 555}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 255, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 605}}, {'items': [['D', 800, 780]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 605, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
write down{'group_writedown': {'g1': 550}, 'items': [['A', 890, 0]]}{'group_writedown': {'g1': 550}, 'items': [['A', 890, -550]]}Failed
no write down{'group_writedown': {'g1': 0}, 'items': [['B', 500, 0]]}{'group_writedown': {'g1': 0}, 'items': [['B', 500, 0]]}Passed
negative nrv{'group_writedown': {'g2': 1200}, 'items': [['C', 0, 0]]}{'group_writedown': {'g2': 1200}, 'items': [['C', 0, -1200]]}Failed
reversal capped{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}Passed
partial reversal{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}Passed
group offset{'group_writedown': {'g3': 0}, 'items': [['F', 700, 0], ['G', 200, 0]]}{'group_writedown': {'g3': 0}, 'items': [['F', 700, -300], ['G', 200, 0]]}Failed
group loss{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 0]]}{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 0]]}Passed
costly completion{'group_writedown': {'g5': 250}, 'items': [['K', 50, 0]]}{'group_writedown': {'g5': 250}, 'items': [['K', 50, -250]]}Failed

SHA-256 / 7abed80038c5ab570cdd1cd1ce0a163896ec419edb7ca6b92611d39cc643918d

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    res = []
    groups = {}
    for it in x['items']:
        sell = (it['price'] * it['sell_bp'] + 5000) // 10000
        nrv = it['price'] - it['complete'] - sell
        if nrv < 0:
            nrv = 0
        carry = min(it['cost'], nrv)
        prior = x['prior'].get(it['sku'], it['cost'])
        res.append([it['sku'], carry, it['qty'] * (carry - prior)])
        g = groups.setdefault(it['group'], [0, 0])
        g[0] += it['qty'] * it['cost']
        g[1] += it['qty'] * nrv
    gw = {k: max(0, v[0] - v[1]) for k, v in sorted(groups.items())}
    return {'items': res, 'group_writedown': gw}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1001, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 251, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 601}}, {'items': [['D', 800, 796]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 601, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1002, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 252, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 602}}, {'items': [['D', 800, 792]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 602, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1003, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 253, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 603}}, {'items': [['D', 800, 788]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 603, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1004, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 890, -550]], 'group_writedown': {'g1': 550}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 254, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 604}}, {'items': [['D', 800, 784]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 604, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]], [['write down', {'items': [{'sku': 'A', 'qty': 5, 'cost': 1000, 'price': 1100, 'complete': 100, 'sell_bp': 1005, 'group': 'g1'}], 'prior': {}}, {'items': [['A', 889, -555]], 'group_writedown': {'g1': 555}}], ['no write down', {'items': [{'sku': 'B', 'qty': 2, 'cost': 500, 'price': 900, 'complete': 50, 'sell_bp': 500, 'group': 'g1'}], 'prior': {}}, {'items': [['B', 500, 0]], 'group_writedown': {'g1': 0}}], ['negative nrv', {'items': [{'sku': 'C', 'qty': 3, 'cost': 400, 'price': 300, 'complete': 255, 'sell_bp': 2000, 'group': 'g2'}], 'prior': {}}, {'items': [['C', 0, -1200]], 'group_writedown': {'g2': 1200}}], ['reversal capped', {'items': [{'sku': 'D', 'qty': 4, 'cost': 800, 'price': 1500, 'complete': 0, 'sell_bp': 0, 'group': 'g2'}], 'prior': {'D': 605}}, {'items': [['D', 800, 780]], 'group_writedown': {'g2': 0}}], ['partial reversal', {'items': [{'sku': 'E', 'qty': 1, 'cost': 800, 'price': 850, 'complete': 0, 'sell_bp': 1000, 'group': 'g1'}], 'prior': {'E': 700}}, {'items': [['E', 765, 65]], 'group_writedown': {'g1': 35}}], ['group offset', {'items': [{'sku': 'F', 'qty': 1, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}, {'sku': 'G', 'qty': 1, 'cost': 200, 'price': 605, 'complete': 0, 'sell_bp': 0, 'group': 'g3'}], 'prior': {}}, {'items': [['F', 700, -300], ['G', 200, 0]], 'group_writedown': {'g3': 0}}], ['group loss', {'items': [{'sku': 'H', 'qty': 2, 'cost': 1000, 'price': 700, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}, {'sku': 'J', 'qty': 1, 'cost': 200, 'price': 250, 'complete': 0, 'sell_bp': 0, 'group': 'g4'}], 'prior': {'H': 900}}, {'items': [['H', 700, -400], ['J', 200, 0]], 'group_writedown': {'g4': 550}}], ['costly completion', {'items': [{'sku': 'K', 'qty': 1, 'cost': 300, 'price': 1000, 'complete': 900, 'sell_bp': 500, 'group': 'g5'}], 'prior': {}}, {'items': [['K', 50, -250]], 'group_writedown': {'g5': 250}}]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
write down{'group_writedown': {'g1': 550}, 'items': [['A', 890, -550]]}{'group_writedown': {'g1': 550}, 'items': [['A', 890, -550]]}Passed
no write down{'group_writedown': {'g1': 0}, 'items': [['B', 500, 0]]}{'group_writedown': {'g1': 0}, 'items': [['B', 500, 0]]}Passed
negative nrv{'group_writedown': {'g2': 1200}, 'items': [['C', 0, -1200]]}{'group_writedown': {'g2': 1200}, 'items': [['C', 0, -1200]]}Passed
reversal capped{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}{'group_writedown': {'g2': 0}, 'items': [['D', 800, 796]]}Passed
partial reversal{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}{'group_writedown': {'g1': 35}, 'items': [['E', 765, 65]]}Passed
group offset{'group_writedown': {'g3': 0}, 'items': [['F', 700, -300], ['G', 200, 0]]}{'group_writedown': {'g3': 0}, 'items': [['F', 700, -300], ['G', 200, 0]]}Passed
group loss{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 0]]}{'group_writedown': {'g4': 550}, 'items': [['H', 700, -400], ['J', 200, 0]]}Passed
costly completion{'group_writedown': {'g5': 250}, 'items': [['K', 50, -250]]}{'group_writedown': {'g5': 250}, 'items': [['K', 50, -250]]}Passed

SHA-256 / cab7615eb088898bedc5511cbbba4cef678413df4b02fa2c7e837fdbbd4b6245

Verification & scope

Stipulated bounded teaching model with explicit toy rules; not an accounting-standard implementation. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:46:41.453714+00:00.

Case digest / 846d31bda1ea3b6435ced3acffc442c95458b0782d7b75440ab393f609749c7b