FA-76446 / Email MIME structure / Open access

Resolve and de-duplicate attachment file names: dot name rejection · case 01

A filename of ".." or "." is accepted and later resolves to a directory.

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ROOT CAUSE

The dot name rejection decision evaluates `('',)` where the contract requires `('', '.', '..')`.

THE FAILURE

The dot name rejection decision evaluates `('',)` where the contract requires `('', '.', '..')`.

Unsuccessful approach: Rejecting "." but not ".." still lets the parent-directory name through. The attempted `('', '.')` still disagrees with a fixture.

Case contract

Each part has optional fstar (already decoded filename*), fname (filename) and ctname (Content-Type name) and a type. Precedence is fstar, fname, ctname. Directory components are removed (both "/" and "\" separate). An empty name, "." or ".." becomes "attachment" plus an extension by type (.pdf, .png, .txt, else .bin). Names are de-duplicated case-insensitively: the k-th copy gets " (k)" before the last extension, or at the end when there is no extension or the name starts with its only dot.

Why this case matters

Attachment names end up on disk; wrong names overwrite files, leak paths or confuse users.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(parts):
    exts = {'application/pdf': '.pdf', 'image/png': '.png', 'text/plain': '.txt'}
    used = {}
    out = []
    for p in parts:
        raw = p.get('fstar') or p.get('fname') or p.get('ctname') or ''
        base = raw.replace('\\', '/').split('/')[-1]
        if base in ('',):
            base = 'attachment' + exts.get(p['type'], '.bin')
        key = base.lower()
        used[key] = used.get(key, 0) + 1
        if used[key] > 1:
            stem, dot, ext = base.rpartition('.')
            base = (stem + ' (%d).' % used[key] + ext) if dot and stem else base + ' (%d)' % used[key]
        out.append(base)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_CASES = {1: [('extended name wins', ([{'fstar': 'résumé1.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé1.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report1.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report1.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report1.PDF', 'type': 'application/pdf'}, {'ctname': 'report1.pdf', 'type': 'application/pdf'}],), ['Report1.PDF', 'report1 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x1.png', 'type': 'image/png'}, {'fname': 'x1.png', 'type': 'image/png'}, {'fname': 'x1.png', 'type': 'image/png'}],), ['x1.png', 'x1 (2).png', 'x1 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 2: [('extended name wins', ([{'fstar': 'résumé2.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé2.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report2.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report2.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report2.PDF', 'type': 'application/pdf'}, {'ctname': 'report2.pdf', 'type': 'application/pdf'}],), ['Report2.PDF', 'report2 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x2.png', 'type': 'image/png'}, {'fname': 'x2.png', 'type': 'image/png'}, {'fname': 'x2.png', 'type': 'image/png'}],), ['x2.png', 'x2 (2).png', 'x2 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 3: [('extended name wins', ([{'fstar': 'résumé3.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé3.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report3.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report3.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report3.PDF', 'type': 'application/pdf'}, {'ctname': 'report3.pdf', 'type': 'application/pdf'}],), ['Report3.PDF', 'report3 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x3.png', 'type': 'image/png'}, {'fname': 'x3.png', 'type': 'image/png'}, {'fname': 'x3.png', 'type': 'image/png'}],), ['x3.png', 'x3 (2).png', 'x3 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 4: [('extended name wins', ([{'fstar': 'résumé4.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé4.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report4.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report4.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report4.PDF', 'type': 'application/pdf'}, {'ctname': 'report4.pdf', 'type': 'application/pdf'}],), ['Report4.PDF', 'report4 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x4.png', 'type': 'image/png'}, {'fname': 'x4.png', 'type': 'image/png'}, {'fname': 'x4.png', 'type': 'image/png'}],), ['x4.png', 'x4 (2).png', 'x4 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 5: [('extended name wins', ([{'fstar': 'résumé5.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé5.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report5.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report5.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report5.PDF', 'type': 'application/pdf'}, {'ctname': 'report5.pdf', 'type': 'application/pdf'}],), ['Report5.PDF', 'report5 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x5.png', 'type': 'image/png'}, {'fname': 'x5.png', 'type': 'image/png'}, {'fname': 'x5.png', 'type': 'image/png'}],), ['x5.png', 'x5 (2).png', 'x5 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])]}
for _label, _args, _expected in _CASES[N]:
    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 fixture	Actual	Expected	Outcome
extended name wins	`['résumé1.pdf']`	`['résumé1.pdf']`	Passed
windows path	`['report1.docx', 'passwd']`	`['report1.docx', 'passwd']`	Passed
dot names	`['..', '.']`	`['attachment.png', 'attachment.txt']`	Failed
case-insensitive duplicates	`['Report1.PDF', 'report1 (2).pdf']`	`['Report1.PDF', 'report1 (2).pdf']`	Passed
multi-dot duplicate	`['archive.tar.gz', 'archive.tar (2).gz']`	`['archive.tar.gz', 'archive.tar (2).gz']`	Passed
dotfile and short stem	`['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']`	`['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']`	Passed
third copy	`['x1.png', 'x1 (2).png', 'x1 (3).png']`	`['x1.png', 'x1 (2).png', 'x1 (3).png']`	Passed
no name at all	`['attachment.bin', 'attachment.pdf']`	`['attachment.bin', 'attachment.pdf']`	Passed

SHA-256 / 959ba0efd6a4742d6dcf88bb27858e3819390b339a51866198fda7d7c3469ae1

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(parts):
    exts = {'application/pdf': '.pdf', 'image/png': '.png', 'text/plain': '.txt'}
    used = {}
    out = []
    for p in parts:
        raw = p.get('fstar') or p.get('fname') or p.get('ctname') or ''
        base = raw.replace('\\', '/').split('/')[-1]
        if base in ('', '.'):
            base = 'attachment' + exts.get(p['type'], '.bin')
        key = base.lower()
        used[key] = used.get(key, 0) + 1
        if used[key] > 1:
            stem, dot, ext = base.rpartition('.')
            base = (stem + ' (%d).' % used[key] + ext) if dot and stem else base + ' (%d)' % used[key]
        out.append(base)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_CASES = {1: [('extended name wins', ([{'fstar': 'résumé1.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé1.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report1.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report1.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report1.PDF', 'type': 'application/pdf'}, {'ctname': 'report1.pdf', 'type': 'application/pdf'}],), ['Report1.PDF', 'report1 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x1.png', 'type': 'image/png'}, {'fname': 'x1.png', 'type': 'image/png'}, {'fname': 'x1.png', 'type': 'image/png'}],), ['x1.png', 'x1 (2).png', 'x1 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 2: [('extended name wins', ([{'fstar': 'résumé2.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé2.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report2.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report2.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report2.PDF', 'type': 'application/pdf'}, {'ctname': 'report2.pdf', 'type': 'application/pdf'}],), ['Report2.PDF', 'report2 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x2.png', 'type': 'image/png'}, {'fname': 'x2.png', 'type': 'image/png'}, {'fname': 'x2.png', 'type': 'image/png'}],), ['x2.png', 'x2 (2).png', 'x2 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 3: [('extended name wins', ([{'fstar': 'résumé3.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé3.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report3.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report3.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report3.PDF', 'type': 'application/pdf'}, {'ctname': 'report3.pdf', 'type': 'application/pdf'}],), ['Report3.PDF', 'report3 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x3.png', 'type': 'image/png'}, {'fname': 'x3.png', 'type': 'image/png'}, {'fname': 'x3.png', 'type': 'image/png'}],), ['x3.png', 'x3 (2).png', 'x3 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 4: [('extended name wins', ([{'fstar': 'résumé4.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé4.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report4.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report4.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report4.PDF', 'type': 'application/pdf'}, {'ctname': 'report4.pdf', 'type': 'application/pdf'}],), ['Report4.PDF', 'report4 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x4.png', 'type': 'image/png'}, {'fname': 'x4.png', 'type': 'image/png'}, {'fname': 'x4.png', 'type': 'image/png'}],), ['x4.png', 'x4 (2).png', 'x4 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])], 5: [('extended name wins', ([{'fstar': 'résumé5.pdf', 'fname': 'resume.pdf', 'ctname': 'r.pdf', 'type': 'application/pdf'}],), ['résumé5.pdf']), ('windows path', ([{'fname': 'C:\\Users\\bo\\report5.docx', 'type': 'application/msword'}, {'fname': '../../etc/passwd', 'type': 'text/plain'}],), ['report5.docx', 'passwd']), ('dot names', ([{'fname': '..', 'type': 'image/png'}, {'fname': '.', 'type': 'text/plain'}],), ['attachment.png', 'attachment.txt']), ('case-insensitive duplicates', ([{'fname': 'Report5.PDF', 'type': 'application/pdf'}, {'ctname': 'report5.pdf', 'type': 'application/pdf'}],), ['Report5.PDF', 'report5 (2).pdf']), ('multi-dot duplicate', ([{'fname': 'archive.tar.gz', 'type': 'application/gzip'}, {'fname': 'archive.tar.gz', 'type': 'application/gzip'}],), ['archive.tar.gz', 'archive.tar (2).gz']), ('dotfile and short stem', ([{'fname': '.profile', 'type': 'text/plain'}, {'fname': '.profile', 'type': 'text/plain'}, {'fname': 'a.pdf', 'type': 'application/pdf'}, {'fname': 'a.pdf', 'type': 'application/pdf'}],), ['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']), ('third copy', ([{'fname': 'x5.png', 'type': 'image/png'}, {'fname': 'x5.png', 'type': 'image/png'}, {'fname': 'x5.png', 'type': 'image/png'}],), ['x5.png', 'x5 (2).png', 'x5 (3).png']), ('no name at all', ([{'type': 'application/zip'}, {'type': 'application/pdf'}],), ['attachment.bin', 'attachment.pdf'])]}
for _label, _args, _expected in _CASES[N]:
    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 fixture	Actual	Expected	Outcome
extended name wins	`['résumé1.pdf']`	`['résumé1.pdf']`	Passed
windows path	`['report1.docx', 'passwd']`	`['report1.docx', 'passwd']`	Passed
dot names	`['..', 'attachment.txt']`	`['attachment.png', 'attachment.txt']`	Failed
case-insensitive duplicates	`['Report1.PDF', 'report1 (2).pdf']`	`['Report1.PDF', 'report1 (2).pdf']`	Passed
multi-dot duplicate	`['archive.tar.gz', 'archive.tar (2).gz']`	`['archive.tar.gz', 'archive.tar (2).gz']`	Passed
dotfile and short stem	`['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']`	`['.profile', '.profile (2)', 'a.pdf', 'a (2).pdf']`	Passed
third copy	`['x1.png', 'x1 (2).png', 'x1 (3).png']`	`['x1.png', 'x1 (2).png', 'x1 (3).png']`	Passed
no name at all	`['attachment.bin', 'attachment.pdf']`	`['attachment.bin', 'attachment.pdf']`	Passed

SHA-256 / 1b983c48275eb45575ebaf207527489532e99b6e36b5712596188231022b2472

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 8 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

Stipulated offline model over pre-parsed MIME dictionaries; not a conforming MIME parser, generator or mail client. 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 2026-09-29T14:49:16.552420+00:00.

Case digest / f09488fb882b1c93d0c4e28e63d1f87431797664d825ee5cbe03d3c7ff375088