FA-79331 / Image orientation metadata / Open access

Embedded-first policy never falls back to the sidecar · case 01

Files without an embedded tag display unrotated even though the sidecar holds a valid orientation.

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

ROOT CAUSE

The embedded policy lists only the embedded value.

VERIFIED REPAIR

Fall back to the sidecar when the embedded value is invalid.

Unsuccessful approach: Appending None keeps the list the same length but still skips the sidecar.

Case contract

A photo manager reconciles the embedded orientation with an XMP sidecar. Values are valid if they are integers 1..8 or strings that are exactly one digit 1..8 after trimming. Policy "sidecar" prefers the sidecar, "embedded" prefers the file, and "newest" (also used for unknown policies) prefers the sidecar when both are valid and sidecar_mtime >= file_mtime; the other valid value is the fallback, then 1.

Why this case matters

Camera, phone and scanner images carry an orientation hint separately from the stored pixels; galleries, thumbnailers, editors and upload pipelines must interpret it consistently or photos appear sideways, mirrored or doubly rotated.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(d):
    def ok(v):
        if isinstance(v, str) and v.strip() in ('1', '2', '3', '4', '5', '6', '7', '8'):
            return int(v.strip())
        if isinstance(v, int) and not isinstance(v, bool) and 1 <= v <= 8:
            return v
        return None
    e = ok(d.get('embedded'))
    s = ok(d.get('sidecar'))
    pol = d.get('policy')
    if pol not in ('newest', 'sidecar', 'embedded'):
        pol = 'newest'
    if pol == 'sidecar':
        order = [s, e]
    elif pol == 'embedded':
        order = [e]
    elif s is not None and e is not None:
        order = [s, e] if d['sidecar_mtime'] >= d['file_mtime'] else [e, s]
    else:
        order = [s, e]
    for v in order:
        if v is not None:
            return v
    return 1
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': 5, 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'embedded'}, 5], [{'embedded': 5, 'sidecar': '+3', 'file_mtime': 103, 'sidecar_mtime': 108, 'policy': 'newest'}, 5], [{'embedded': 'x', 'sidecar': 'x', 'file_mtime': 109, 'sidecar_mtime': 109, 'policy': 'embedded'}, 1], [{'embedded': 8, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'newest'}, 8], [{'embedded': 9, 'sidecar': 9, 'file_mtime': 108, 'sidecar_mtime': 109, 'policy': None}, 1], [{'embedded': ' 8', 'sidecar': 5, 'file_mtime': 105, 'sidecar_mtime': 105, 'policy': 'newest'}, 5], [{'embedded': 9, 'sidecar': 3, 'file_mtime': 106, 'sidecar_mtime': 111, 'policy': 'embedded'}, 3]], [[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': None, 'file_mtime': 106, 'sidecar_mtime': 106, 'policy': 'embedded'}, 3], [{'embedded': 1, 'sidecar': '06', 'file_mtime': 104, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 1], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 107, 'sidecar_mtime': 112, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 96, 'policy': 'sidecar'}, 6], [{'embedded': 3, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'newest'}, 3], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 110, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': None, 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 109, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': '06', 'file_mtime': 110, 'sidecar_mtime': 115, 'policy': 'newest'}, 1], [{'embedded': 3, 'sidecar': '+3', 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': None}, 3], [{'embedded': ' 8', 'sidecar': 3, 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'latest'}, 3], [{'embedded': 8, 'sidecar': 1, 'file_mtime': 108, 'sidecar_mtime': 108, 'policy': None}, 1], [{'embedded': 'x', 'sidecar': ' 8', 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 5, 'sidecar': 9, 'file_mtime': 105, 'sidecar_mtime': 110, 'policy': 'latest'}, 5], [{'embedded': 'x', 'sidecar': 5, 'file_mtime': 103, 'sidecar_mtime': 98, 'policy': 'embedded'}, 5]], [[{'embedded': 0, 'sidecar': 3, 'file_mtime': 101, 'sidecar_mtime': 100, 'policy': 'embedded'}, 3], [{'embedded': '06', 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 1, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'newest'}, 1], [{'embedded': 6, 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 6], [{'embedded': 5, 'sidecar': 8, 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': 'newest'}, 8], [{'embedded': None, 'sidecar': '6', 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'latest'}, 6], [{'embedded': 'x', 'sidecar': 8, 'file_mtime': 103, 'sidecar_mtime': 102, 'policy': None}, 8], [{'embedded': 9, 'sidecar': 8, 'file_mtime': 106, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': 9, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 105, 'sidecar_mtime': 104, 'policy': 'embedded'}, 8], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 110, 'sidecar_mtime': 110, 'policy': 'embedded'}, 8], [{'embedded': 0, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 1], [{'embedded': 0, 'sidecar': 9, 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'latest'}, 1], [{'embedded': ' 8', 'sidecar': 0, 'file_mtime': 100, 'sidecar_mtime': 100, 'policy': None}, 8], [{'embedded': 8, 'sidecar': 9, 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 0, 'sidecar': '6', 'file_mtime': 108, 'sidecar_mtime': 113, 'policy': 'embedded'}, 6]]]
labels = ["regression: embedded policy fallback", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), 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 fixture	Actual	Expected	Outcome
regression: embedded policy fallback 0	`1`	`6`	Failed
repair trap 1	`1`	`5`	Failed
combined fault 2	`5`	`5`	Passed
control 3	`1`	`1`	Passed
control 4	`8`	`8`	Passed
boundary 5	`1`	`1`	Passed
boundary 6	`5`	`5`	Passed
control 7	`1`	`3`	Failed

SHA-256 / 76678a78a958f70a8c47c2abd542c8b737f6a51670b7a6593761e7426a615d98

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(d):
    def ok(v):
        if isinstance(v, str) and v.strip() in ('1', '2', '3', '4', '5', '6', '7', '8'):
            return int(v.strip())
        if isinstance(v, int) and not isinstance(v, bool) and 1 <= v <= 8:
            return v
        return None
    e = ok(d.get('embedded'))
    s = ok(d.get('sidecar'))
    pol = d.get('policy')
    if pol not in ('newest', 'sidecar', 'embedded'):
        pol = 'newest'
    if pol == 'sidecar':
        order = [s, e]
    elif pol == 'embedded':
        order = [e, None]
    elif s is not None and e is not None:
        order = [s, e] if d['sidecar_mtime'] >= d['file_mtime'] else [e, s]
    else:
        order = [s, e]
    for v in order:
        if v is not None:
            return v
    return 1
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': 5, 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'embedded'}, 5], [{'embedded': 5, 'sidecar': '+3', 'file_mtime': 103, 'sidecar_mtime': 108, 'policy': 'newest'}, 5], [{'embedded': 'x', 'sidecar': 'x', 'file_mtime': 109, 'sidecar_mtime': 109, 'policy': 'embedded'}, 1], [{'embedded': 8, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'newest'}, 8], [{'embedded': 9, 'sidecar': 9, 'file_mtime': 108, 'sidecar_mtime': 109, 'policy': None}, 1], [{'embedded': ' 8', 'sidecar': 5, 'file_mtime': 105, 'sidecar_mtime': 105, 'policy': 'newest'}, 5], [{'embedded': 9, 'sidecar': 3, 'file_mtime': 106, 'sidecar_mtime': 111, 'policy': 'embedded'}, 3]], [[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': None, 'file_mtime': 106, 'sidecar_mtime': 106, 'policy': 'embedded'}, 3], [{'embedded': 1, 'sidecar': '06', 'file_mtime': 104, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 1], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 107, 'sidecar_mtime': 112, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 96, 'policy': 'sidecar'}, 6], [{'embedded': 3, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'newest'}, 3], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 110, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': None, 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 109, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': '06', 'file_mtime': 110, 'sidecar_mtime': 115, 'policy': 'newest'}, 1], [{'embedded': 3, 'sidecar': '+3', 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': None}, 3], [{'embedded': ' 8', 'sidecar': 3, 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'latest'}, 3], [{'embedded': 8, 'sidecar': 1, 'file_mtime': 108, 'sidecar_mtime': 108, 'policy': None}, 1], [{'embedded': 'x', 'sidecar': ' 8', 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 5, 'sidecar': 9, 'file_mtime': 105, 'sidecar_mtime': 110, 'policy': 'latest'}, 5], [{'embedded': 'x', 'sidecar': 5, 'file_mtime': 103, 'sidecar_mtime': 98, 'policy': 'embedded'}, 5]], [[{'embedded': 0, 'sidecar': 3, 'file_mtime': 101, 'sidecar_mtime': 100, 'policy': 'embedded'}, 3], [{'embedded': '06', 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 1, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'newest'}, 1], [{'embedded': 6, 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 6], [{'embedded': 5, 'sidecar': 8, 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': 'newest'}, 8], [{'embedded': None, 'sidecar': '6', 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'latest'}, 6], [{'embedded': 'x', 'sidecar': 8, 'file_mtime': 103, 'sidecar_mtime': 102, 'policy': None}, 8], [{'embedded': 9, 'sidecar': 8, 'file_mtime': 106, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': 9, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 105, 'sidecar_mtime': 104, 'policy': 'embedded'}, 8], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 110, 'sidecar_mtime': 110, 'policy': 'embedded'}, 8], [{'embedded': 0, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 1], [{'embedded': 0, 'sidecar': 9, 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'latest'}, 1], [{'embedded': ' 8', 'sidecar': 0, 'file_mtime': 100, 'sidecar_mtime': 100, 'policy': None}, 8], [{'embedded': 8, 'sidecar': 9, 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 0, 'sidecar': '6', 'file_mtime': 108, 'sidecar_mtime': 113, 'policy': 'embedded'}, 6]]]
labels = ["regression: embedded policy fallback", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), 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 fixture	Actual	Expected	Outcome
regression: embedded policy fallback 0	`1`	`6`	Failed
repair trap 1	`1`	`5`	Failed
combined fault 2	`5`	`5`	Passed
control 3	`1`	`1`	Passed
control 4	`8`	`8`	Passed
boundary 5	`1`	`1`	Passed
boundary 6	`5`	`5`	Passed
control 7	`1`	`3`	Failed

SHA-256 / 7ec0050f5aa8eda2d1add29d1ee91dce1763ee75001da91a58ac3cb82b2d12b8

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(d):
    def ok(v):
        if isinstance(v, str) and v.strip() in ('1', '2', '3', '4', '5', '6', '7', '8'):
            return int(v.strip())
        if isinstance(v, int) and not isinstance(v, bool) and 1 <= v <= 8:
            return v
        return None
    e = ok(d.get('embedded'))
    s = ok(d.get('sidecar'))
    pol = d.get('policy')
    if pol not in ('newest', 'sidecar', 'embedded'):
        pol = 'newest'
    if pol == 'sidecar':
        order = [s, e]
    elif pol == 'embedded':
        order = [e, s]
    elif s is not None and e is not None:
        order = [s, e] if d['sidecar_mtime'] >= d['file_mtime'] else [e, s]
    else:
        order = [s, e]
    for v in order:
        if v is not None:
            return v
    return 1
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': 5, 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'embedded'}, 5], [{'embedded': 5, 'sidecar': '+3', 'file_mtime': 103, 'sidecar_mtime': 108, 'policy': 'newest'}, 5], [{'embedded': 'x', 'sidecar': 'x', 'file_mtime': 109, 'sidecar_mtime': 109, 'policy': 'embedded'}, 1], [{'embedded': 8, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'newest'}, 8], [{'embedded': 9, 'sidecar': 9, 'file_mtime': 108, 'sidecar_mtime': 109, 'policy': None}, 1], [{'embedded': ' 8', 'sidecar': 5, 'file_mtime': 105, 'sidecar_mtime': 105, 'policy': 'newest'}, 5], [{'embedded': 9, 'sidecar': 3, 'file_mtime': 106, 'sidecar_mtime': 111, 'policy': 'embedded'}, 3]], [[{'embedded': 'x', 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': None, 'file_mtime': 106, 'sidecar_mtime': 106, 'policy': 'embedded'}, 3], [{'embedded': 1, 'sidecar': '06', 'file_mtime': 104, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 1], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 107, 'sidecar_mtime': 112, 'policy': 'embedded'}, 8], [{'embedded': 3, 'sidecar': 6, 'file_mtime': 101, 'sidecar_mtime': 96, 'policy': 'sidecar'}, 6], [{'embedded': 3, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 103, 'policy': 'newest'}, 3], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 110, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': None, 'sidecar': 6, 'file_mtime': 104, 'sidecar_mtime': 109, 'policy': 'embedded'}, 6], [{'embedded': None, 'sidecar': '06', 'file_mtime': 110, 'sidecar_mtime': 115, 'policy': 'newest'}, 1], [{'embedded': 3, 'sidecar': '+3', 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': None}, 3], [{'embedded': ' 8', 'sidecar': 3, 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'latest'}, 3], [{'embedded': 8, 'sidecar': 1, 'file_mtime': 108, 'sidecar_mtime': 108, 'policy': None}, 1], [{'embedded': 'x', 'sidecar': ' 8', 'file_mtime': 101, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 5, 'sidecar': 9, 'file_mtime': 105, 'sidecar_mtime': 110, 'policy': 'latest'}, 5], [{'embedded': 'x', 'sidecar': 5, 'file_mtime': 103, 'sidecar_mtime': 98, 'policy': 'embedded'}, 5]], [[{'embedded': 0, 'sidecar': 3, 'file_mtime': 101, 'sidecar_mtime': 100, 'policy': 'embedded'}, 3], [{'embedded': '06', 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 1, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'newest'}, 1], [{'embedded': 6, 'sidecar': 6, 'file_mtime': 100, 'sidecar_mtime': 105, 'policy': 'sidecar'}, 6], [{'embedded': 5, 'sidecar': 8, 'file_mtime': 109, 'sidecar_mtime': 114, 'policy': 'newest'}, 8], [{'embedded': None, 'sidecar': '6', 'file_mtime': 104, 'sidecar_mtime': 104, 'policy': 'latest'}, 6], [{'embedded': 'x', 'sidecar': 8, 'file_mtime': 103, 'sidecar_mtime': 102, 'policy': None}, 8], [{'embedded': 9, 'sidecar': 8, 'file_mtime': 106, 'sidecar_mtime': 105, 'policy': 'embedded'}, 8]], [[{'embedded': 9, 'sidecar': '6', 'file_mtime': 100, 'sidecar_mtime': 95, 'policy': 'embedded'}, 6], [{'embedded': 9, 'sidecar': ' 8', 'file_mtime': 105, 'sidecar_mtime': 104, 'policy': 'embedded'}, 8], [{'embedded': ' 8', 'sidecar': 8, 'file_mtime': 110, 'sidecar_mtime': 110, 'policy': 'embedded'}, 8], [{'embedded': 0, 'sidecar': 'x', 'file_mtime': 102, 'sidecar_mtime': 102, 'policy': 'embedded'}, 1], [{'embedded': 0, 'sidecar': 9, 'file_mtime': 100, 'sidecar_mtime': 99, 'policy': 'latest'}, 1], [{'embedded': ' 8', 'sidecar': 0, 'file_mtime': 100, 'sidecar_mtime': 100, 'policy': None}, 8], [{'embedded': 8, 'sidecar': 9, 'file_mtime': 102, 'sidecar_mtime': 101, 'policy': 'sidecar'}, 8], [{'embedded': 0, 'sidecar': '6', 'file_mtime': 108, 'sidecar_mtime': 113, 'policy': 'embedded'}, 6]]]
labels = ["regression: embedded policy fallback", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), 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 fixture	Actual	Expected	Outcome
regression: embedded policy fallback 0	`6`	`6`	Passed
repair trap 1	`5`	`5`	Passed
combined fault 2	`5`	`5`	Passed
control 3	`1`	`1`	Passed
control 4	`8`	`8`	Passed
boundary 5	`1`	`1`	Passed
boundary 6	`5`	`5`	Passed
control 7	`3`	`3`	Passed

SHA-256 / e756cb91b38d23bd46b05c3800105414940372177e77af67c7d2b486f252fa08

Verification & scope

A deterministic bounded teaching model with a stipulated contract; it makes no claim of conformance to any published specification. 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 2026-09-29T14:49:43.714328+00:00.

Case digest / 88b84dcc78f9699a4e2b1c4c795950dc93d3cfd008971913a06c515512faff94