pptx/package-thumbnail-dropped

Metadata

XPath assertions

Render assertions

No render assertions declared.

Generator source

scripts/gen_pptx_package_thumbnail_dropped.py

#!/usr/bin/env python3
"""Generate ``fixtures/pptx/package-thumbnail-dropped.pptx``.

Sibling of ``gen_package_thumbnail_dropped.py`` (docx) but for
python-pptx. As of 2026.05 python-pptx does NOT drop the template
thumbnail on save, so the generated fixture still ships
``docProps/thumbnail.jpeg`` and the conformance manifest fails
deliberately — the failure is the tombstone motivating a future
port of python-docx's `_drop_unused_package_rels` to python-pptx.
"""

from __future__ import annotations

from pathlib import Path

from pptx import Presentation

_REPO_ROOT = Path(__file__).resolve().parent.parent
_OUT = _REPO_ROOT / "fixtures" / "pptx" / "package-thumbnail-dropped.pptx"


def main() -> int:
    prs = Presentation()
    prs.slides.add_slide(prs.slide_layouts[0])
    _OUT.parent.mkdir(parents=True, exist_ok=True)
    prs.save(_OUT)
    print(_OUT)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())

Manifest (expanded)

{
  "$schema": "../manifest.schema.json",
  "id": "pptx/package-thumbnail-dropped",
  "title": "Package thumbnail dropped on save",
  "format": "pptx",
  "category": "packaging",
  "summary": "Authoring library should drop the template thumbnail so the saved package never ships a stale preview image.",
  "roles": [
    "authoring"
  ],
  "spec": {
    "source": "ecma-376-5-part-2",
    "clause": "10.1.10",
    "notes": "The python-pptx default template (src/pptx/templates/default.pptx) carries a rendered `docProps/thumbnail.jpeg`. As of 2026.05 python-pptx does NOT drop it on save, so the generated fixture still contains the stale template preview and the assertion FAILS. That failure is the tombstone: the fix is to port python-docx's `_drop_unused_package_rels` pattern into python-pptx. Tracked by a future wave — this manifest is the known-failing marker that will flip green when the port lands."
  },
  "fixtures": {
    "machine": "pptx/package-thumbnail-dropped"
  },
  "generator": {
    "python": "scripts/gen_pptx_package_thumbnail_dropped.py"
  },
  "assertions": [
    {
      "id": "thumbnail-part-absent",
      "kind": "zip_contains_path",
      "path": "docProps/thumbnail.jpeg",
      "must": "absent",
      "description": "`docProps/thumbnail.jpeg` SHOULD NOT appear in the output package. Currently expected to fail for python-pptx until the drop is implemented."
    }
  ]
}