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FA-50656 / Raster clipping / Open access

Damage history clip: failed present · case 01

Failed presentation advances history even though the backbuffer was not swapped.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Failed presentation advances history even though the backbuffer was not swapped.

VERIFIED REPAIR

Apply the documented state transition at failed present. Each frame begins with current damage and backbuffer age. Age zero requires full redraw; age k includes current damage and the last k-1 successfully presented frames. Failed presentation neither stores history nor clears accumulated damage. Bounds are applied before drawing; explicit full damage survives incremental additions.

Unsuccessful approach: Treating the first failed presentation as initialization consumes damage without a swap.

Case contract

Each frame begins with current damage and backbuffer age. Age zero requires full redraw; age k includes current damage and the last k-1 successfully presented frames. Failed presentation neither stores history nor clears accumulated damage. Bounds are applied before drawing; explicit full damage survives incremental additions.

Why this case matters

Raster clip state can leak coverage across draws even when every individual region is valid.

1 / The failure

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

N = 1
observations = []
def solve(commands, size):
    full=set(range(size))
    history=[]
    current=set()
    redraw=set()
    out=[]
    for cmd in commands:
        op=cmd[0]
        if op=='damage': current |= set(cmd[1]) & full
        elif op=='full': current=set(full)
        elif op=='begin':
            age=cmd[1]
            if age==0 or age-1>len(history): redraw=set(full)
            else:
                redraw=set(current)
                for old in history[:age-1]: redraw |= old
        elif op=='draw': out.append(sorted(redraw))
        elif op=='present':
            if True:
                history.insert(0,set(current))
                history=history[:3]
                current.clear()
        elif op=='resize':
            full=set(range(cmd[1]))
            history=[]
            current=set(full)
            redraw=set(full)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 4), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 4), [[0, 1, 2, 3], [0, 1, 2, 3]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 4), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 4), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 4), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 4), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 4), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 4), [[0, 1, 2, 3]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 4), [[3]])
if N == 2:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 5), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 5), [[0, 1, 2, 3, 4], [0, 1, 2, 3, 4]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 5), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 5), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 5), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 5), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 5), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 5), [[0, 1, 2, 3, 4]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 5), [[3]])
if N == 3:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 6), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 6), [[0, 1, 2, 3, 4, 5], [0, 1, 2, 3, 4, 5]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 6), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 6), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 6), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 6), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 6), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 6), [[3]])
if N == 4:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 7), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 7), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 7), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 7), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 7), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 7), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 7), [[3]])
if N == 5:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 8), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7], [0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 8), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 8), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 8), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 8), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 8), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 8), [[3]])
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
explicit sequence 0[[0, 1]][[0, 1]]Passed
explicit sequence 1[[0, 1, 2, 3], [0, 1, 2, 3]][[0, 1, 2, 3], [0, 1, 2, 3]]Passed
explicit sequence 2[[1, 2], [0, 1, 2]][[1, 2], [0, 1, 2]]Passed
explicit sequence 3[[0]][[0]]Passed
explicit sequence 4[[]][[0]]Failed
explicit sequence 5[[]][[]]Passed
explicit sequence 6[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 7[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 8[[2]][[2]]Passed
explicit sequence 9[[0, 1, 2, 3]][[0, 1, 2, 3]]Passed
explicit sequence 10[[3]][[3]]Passed

SHA-256 / bbcf1d38afe22a79e123905253b0c0a7881014d27fbabd959d45ade00885d6cf

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(commands, size):
    full=set(range(size))
    history=[]
    current=set()
    redraw=set()
    out=[]
    for cmd in commands:
        op=cmd[0]
        if op=='damage': current |= set(cmd[1]) & full
        elif op=='full': current=set(full)
        elif op=='begin':
            age=cmd[1]
            if age==0 or age-1>len(history): redraw=set(full)
            else:
                redraw=set(current)
                for old in history[:age-1]: redraw |= old
        elif op=='draw': out.append(sorted(redraw))
        elif op=='present':
            if cmd[1] or not history:
                history.insert(0,set(current))
                history=history[:3]
                current.clear()
        elif op=='resize':
            full=set(range(cmd[1]))
            history=[]
            current=set(full)
            redraw=set(full)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 4), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 4), [[0, 1, 2, 3], [0, 1, 2, 3]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 4), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 4), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 4), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 4), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 4), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 4), [[0, 1, 2, 3]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 4), [[3]])
if N == 2:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 5), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 5), [[0, 1, 2, 3, 4], [0, 1, 2, 3, 4]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 5), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 5), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 5), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 5), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 5), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 5), [[0, 1, 2, 3, 4]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 5), [[3]])
if N == 3:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 6), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 6), [[0, 1, 2, 3, 4, 5], [0, 1, 2, 3, 4, 5]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 6), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 6), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 6), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 6), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 6), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 6), [[3]])
if N == 4:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 7), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 7), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 7), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 7), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 7), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 7), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 7), [[3]])
if N == 5:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 8), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7], [0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 8), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 8), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 8), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 8), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 8), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 8), [[3]])
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
explicit sequence 0[[0, 1]][[0, 1]]Passed
explicit sequence 1[[0, 1, 2, 3], [0, 1, 2, 3]][[0, 1, 2, 3], [0, 1, 2, 3]]Passed
explicit sequence 2[[1, 2], [0, 1, 2]][[1, 2], [0, 1, 2]]Passed
explicit sequence 3[[0]][[0]]Passed
explicit sequence 4[[]][[0]]Failed
explicit sequence 5[[]][[]]Passed
explicit sequence 6[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 7[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 8[[2]][[2]]Passed
explicit sequence 9[[0, 1, 2, 3]][[0, 1, 2, 3]]Passed
explicit sequence 10[[3]][[3]]Passed

SHA-256 / f31038668e6fc7924ba7d8c8a3a169a73aae07d23fe4d82a9bf9d56b607a2b8a

3 / The verified repair

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

N = 1
observations = []
def solve(commands, size):
    full=set(range(size))
    history=[]
    current=set()
    redraw=set()
    out=[]
    for cmd in commands:
        op=cmd[0]
        if op=='damage': current |= set(cmd[1]) & full
        elif op=='full': current=set(full)
        elif op=='begin':
            age=cmd[1]
            if age==0 or age-1>len(history): redraw=set(full)
            else:
                redraw=set(current)
                for old in history[:age-1]: redraw |= old
        elif op=='draw': out.append(sorted(redraw))
        elif op=='present':
            if cmd[1]:
                history.insert(0,set(current))
                history=history[:3]
                current.clear()
        elif op=='resize':
            full=set(range(cmd[1]))
            history=[]
            current=set(full)
            redraw=set(full)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 4), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 4), [[0, 1, 2, 3], [0, 1, 2, 3]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 4), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 4), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 4), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 4), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 4), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 4), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 4), [[0, 1, 2, 3]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 4), [[3]])
if N == 2:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 5), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 5), [[0, 1, 2, 3, 4], [0, 1, 2, 3, 4]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 5), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 5), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 5), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 5), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 5), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 5), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 5), [[0, 1, 2, 3, 4]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 5), [[3]])
if N == 3:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 6), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 6), [[0, 1, 2, 3, 4, 5], [0, 1, 2, 3, 4, 5]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 6), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 6), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 6), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 6), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 6), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 6), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 6), [[3]])
if N == 4:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 7), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 7), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 7), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 7), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 7), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 7), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 7), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 7), [[3]])
if N == 5:
    check('explicit sequence 0', solve([['damage', [0]], ['damage', [1]], ['begin', 1], ['draw']], 8), [[0, 1]])
    check('explicit sequence 1', solve([['damage', [0]], ['begin', 0], ['draw'], ['begin', 3], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7], [0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 2', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['begin', 2], ['draw'], ['begin', 3], ['draw']], 8), [[1, 2], [0, 1, 2]])
    check('explicit sequence 3', solve([['damage', [0]], ['present', True], ['begin', 2], ['draw']], 8), [[0]])
    check('explicit sequence 4', solve([['damage', [0]], ['present', False], ['begin', 1], ['draw']], 8), [[0]])
    check('explicit sequence 5', solve([['damage', [0]], ['present', True], ['begin', 1], ['draw']], 8), [[]])
    check('explicit sequence 6', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['resize', 3], ['present', True], ['begin', 3], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 7', solve([['damage', [0]], ['present', True], ['resize', 3], ['begin', 1], ['draw']], 8), [[0, 1, 2]])
    check('explicit sequence 8', solve([['damage', [99, -1, 2]], ['begin', 1], ['draw']], 8), [[2]])
    check('explicit sequence 9', solve([['full'], ['damage', [0]], ['begin', 1], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
    check('explicit sequence 10', solve([['damage', [0]], ['present', True], ['damage', [1]], ['present', True], ['damage', [2]], ['present', True], ['damage', [3]], ['present', True], ['begin', 2], ['draw']], 8), [[3]])
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
explicit sequence 0[[0, 1]][[0, 1]]Passed
explicit sequence 1[[0, 1, 2, 3], [0, 1, 2, 3]][[0, 1, 2, 3], [0, 1, 2, 3]]Passed
explicit sequence 2[[1, 2], [0, 1, 2]][[1, 2], [0, 1, 2]]Passed
explicit sequence 3[[0]][[0]]Passed
explicit sequence 4[[0]][[0]]Passed
explicit sequence 5[[]][[]]Passed
explicit sequence 6[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 7[[0, 1, 2]][[0, 1, 2]]Passed
explicit sequence 8[[2]][[2]]Passed
explicit sequence 9[[0, 1, 2, 3]][[0, 1, 2, 3]]Passed
explicit sequence 10[[3]][[3]]Passed

SHA-256 / 7ec690be30151a596ece31e87973b4ace88fcb56e8eedaee96039ad3bc7be497

Verification & scope

Finite one-dimensional integer sample sets model coverage state only; no geometric intersection, memory layout, GPU or graphics-standard conformance is claimed. 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 2026-09-29T14:45:11.289735+00:00.

Case digest / 35ea7f525ac9549da63d6a7b538b4874b43e3b013bfb6a8bb2411451cc8e72f0