EPUB 3 - Intentionally Invalid (duplicate manifest id)
An intentionally invalid EPUB where two manifest items carry the same id, so the spine's references become ambiguous and one chapter can be reached twice while another cannot be reached at all. Intentionally invalid and clearly labelled - an XML ID uniqueness violation, not a container defect.
- mimetype
- container.xml
- content.opf
- nav.xhtml
- style.css
- chapter1.xhtml
- chapter2.xhtml
- chapter3.xhtml
Specifications
- Seed
- 20260807
- Epub Version
- 3.0
- Duplicated Id
- ch2
- Affected Hrefs
- chapter2.xhtml and chapter3.xhtml
- Defect
- two manifest items share the id ch2, so the spine's idrefs are ambiguous
Testing contract
Expected to fail- Scenario
- Parse the package document and resolve each spine idref to a manifest item.
- Expected result
- An XML validator reports the duplicate ID; a reader resolves each idref to the first matching item, so chapter two appears twice and chapter three never enters the reading order.
What is a .epub file?
EPUB is the open e-book standard, a ZIP archive containing XHTML content documents, CSS, images, and a package manifest describing reading order and metadata. It supports reflowable text that adapts to screen size and is supported by most e-readers except Kindle natively. It is the dominant format for distributable e-books.
How to use this file
Use an example EPUB to test e-book parsing, ZIP-package and manifest handling, reading-order and metadata extraction, and rendering in e-reader applications.
How to use this file for testing
“EPUB 3 - Intentionally Invalid (duplicate manifest id)” is a deterministic Novus Examples fixture for Error handling, Conversion testing. Deliberately corrupt and invalid files, clearly labelled, for testing how your tool fails.
Documented properties for this file: seed 20260807. 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.
E-book fixtures are structured archives documented down to their spine and manifest. Test readers and converters, and where a valid↔intentionally-invalid pair exists, assert graceful handling of the malformed container.
Code examples
ebook-convert duplicate-manifest-id.epub out.pdf # Calibre
unzip -l duplicate-manifest-id.epub # EPUB is a ZIPRelated files
- epubEPUB — Intentionally Invalid (bad OCF mimetype)An intentionally invalid EPUB: identical to the valid twin except its OCF mimetype entry is compressed and mislabelled as application/zip — a real EPUB spec violation. For testing how readers and validators handle a malformed container. Clearly labelled; harmless content.
- epubEPUB 3 - Embedded Font, Intentionally Invalid (obfuscation not declared)An intentionally invalid EPUB whose embedded font is IDPF-obfuscated while META-INF/encryption.xml is missing, so nothing in the container says the bytes were scrambled. Intentionally invalid and clearly labelled - this is the real-world failure where a book silently renders in a substitute face.
- epubEPUB 3 - Fixed Layout, Intentionally Invalid (no viewport meta)An intentionally invalid fixed-layout EPUB: rendition:layout says pre-paginated but no content document declares a viewport meta, so the canvas size is undefined. Intentionally invalid and clearly labelled - for testing validators and the fallback a reader picks when it has no dimensions to scale to.
- epubEPUB 3 - Intentionally Invalid (NCX only, no navigation document)An intentionally invalid EPUB 3 that ships only an NCX: no manifest item carries properties="nav", which EPUB 3 requires. Intentionally invalid and clearly labelled - it separates readers that fall back to the NCX from readers that refuse to open a book with no navigation document.
- epubEPUB 3 - MathML, Intentionally Invalid (mathml property missing)An intentionally invalid EPUB: the content document contains MathML while its manifest item omits properties="mathml", so the package understates what a reader needs. Intentionally invalid and clearly labelled - identical to its declared twin in every other byte of markup.
- epubEPUB 3 - Media Overlay with No media:durationA working media overlay whose package omits the required media:duration metadata entirely. Everything else is intact, so this fixture isolates one question: does the reader refuse the overlay, or fall back to measuring the audio itself?
Generated by generation/ebooks_p7.py. Free for any use, no attribution required — license.