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eml554 B

EML — RFC 2047 Subject: ISO-8859-1 'B' Encoding

The ISO-8859-1 Subject again, base64-encoded instead of Q-encoded. Base64 hides the charset entirely, so this is the fixture that catches a decoder guessing the charset from the octets instead of reading the encoded-word's charset token.

Preview — first 13 lineseml
From: Maya Chen <maya@brightside.example>
To: Sam Rivera <sam@meridiansupply.example>
Subject: =?ISO-8859-1?B?Uvxja2ZyYWdlIHp1ciBCZXN0ZWxsdW5nIE5yLiA0NzExIChHcvbfZTogZ3Jv3yk=?=
Date: Mon, 09 Feb 2026 09:03:00 -0800
Message-ID: <p7-ew-latin1-b@brightside.example>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit

This message exists for its Subject header, not its body.
The decoded subject is recorded in the file's specs, so a header decoder
can be checked against a published expected string.

Specifications

Wave
p7
Seed
20260807
Charset
ISO-8859-1
Encoding
B (base64)
Decoded Subject
Rückfrage zur Bestellung Nr. 4711 (Größe: groß)
Bytes Per Character
1
Line Endings
CRLF (RFC 5322)

Testing contract

Expected to pass
Scenario
Decode an ISO-8859-1 'B' Subject where nothing in the base64 payload hints at the charset.
Expected result
Subject decodes to "Rückfrage zur Bestellung Nr. 4711 (Größe: groß)", matching the 'Q' twin exactly once decoded.

What is a .eml file?

An EML file is a single email message stored in the RFC 822 / MIME format — plain-text headers (From, To, Subject, Date, Message-ID) followed by the body, which may be plain text, HTML, or a multipart structure with alternative bodies and file attachments encoded in base64.

How to use this file

Use an example EML to test email header parsing, MIME decoding, HTML-part handling, attachment extraction, and EML-to-other-format conversion.

How to use this file for testing

“EML — RFC 2047 Subject: ISO-8859-1 'B' Encoding” is a deterministic Novus Examples fixture for Email parsing, Encoding detection, Internationalization. Standards-compliant RFC 822 messages — plain, multipart text+HTML, and with an attachment — plus an MBOX mailbox, for testing header parsing, MIME decoding, attachment extraction, and mailbox splitting.

Documented properties for this file: seed 20260807 · B (base64) · CRLF (RFC 5322). Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.

Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.

Email fixtures use fixed dates, message IDs, and MIME boundaries so runs are reproducible, and every address is fictional. Test header parsing, MIME decoding, attachment extraction, and EML/MBOX conversion against the documented structure.

Code examples

from email import policy
from email.parser import BytesParser

msg = BytesParser(policy=policy.default).parse(open("ew-iso8859-1-b.eml", "rb"))
print(msg["subject"], msg["from"])

Generated by generation/email_p7.py. Free for any use, no attribution required — license.