EML — References Folded Before Every Message-ID
An eight-deep References chain folded so each Message-ID sits on its own line. There is no comma between msg-ids in this header, so a parser that splits on the line break rather than unfolding first ends up with ids that carry a leading space.
From: Maya Chen <maya@brightside.example>
To: Sam Rivera <sam@meridiansupply.example>
Subject: Re: Standing order (folded References)
Date: Sat, 14 Feb 2026 08:10:00 -0800
Message-ID: <p7-fold-ref-09@brightside.example>
In-Reply-To: <p7-fold-ref-08@brightside.example>
References: <p7-fold-ref-01@brightside.example>
<p7-fold-ref-02@brightside.example>
<p7-fold-ref-03@brightside.example>
<p7-fold-ref-04@brightside.example>
<p7-fold-ref-05@brightside.example>
<p7-fold-ref-06@brightside.example>
<p7-fold-ref-07@brightside.example>
<p7-fold-ref-08@brightside.example>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
The header block is the fixture here; the body is deliberately short.
Every folded header's unfolded value is recorded in this file's specs.
Specifications
- Wave
- p7
- Seed
- 20260807
- Reference Count
- 8
- Continuation Lines
- 7
- Separator
- fold whitespace only (no comma)
- Line Endings
- CRLF (RFC 5322)
Testing contract
Expected to pass- Scenario
- Unfold a References header whose msg-ids are separated only by folding whitespace and extract the ancestry chain.
- Expected result
- Eight Message-IDs parse in order, each bounded by angle brackets with no embedded whitespace or newline.
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 — References Folded Before Every Message-ID” is a deterministic Novus Examples fixture for Email parsing, Conversion testing. 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 · 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("folding-references-per-line.eml", "rb"))
print(msg["subject"], msg["from"])Related files
- emlEML — Encoded-Word With an Unregistered CharsetAn encoded-word naming a charset no registry knows. The payload happens to be UTF-8, so a decoder has a choice: fall back and show readable text, or leave the raw encoded-word visible. What it must not do is raise and drop the whole header.
- emlEML — Threaded References HeadersA reply carrying In-Reply-To and References headers — for email thread reconstructors.
- emlBounce / Non-Delivery Report (EML)A bounce / non-delivery report (NDR) — a multipart/report message with a human-readable notice, a message/delivery-status part, and the original headers — for testing bounce parsing and delivery-status extraction.
- emlEmail with Attachment (EML)A multipart/mixed email with a base64-encoded CSV file attachment — for testing attachment detection, decoding, and extraction from an EML message.
- emlEML — Attachment With No Filename At AllAn attachment with a bare Content-Disposition: attachment and no name in either header. A client has to invent a filename, and the extension it invents decides whether the saved file opens as a spreadsheet or as unknown binary.
- emlEML — Base64: Accented UTF-8 BodyA base64 text/plain message in utf-8 carrying the identical body to the quoted-printable twin beside it. Base64 is opaque to whitespace and line-start characters, so it is the reference side of the pair when a QP decoder is suspect.
Generated by generation/email_p7.py. Free for any use, no attribution required — license.