Fix: satisfy pyrefly in test_pdf_ops and clarify pdf_ops docstrings

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/documents/pdf_ops.py

@@ -39,7 +39,10 @@ def _require_positive(pages: Iterable[int]) -> None:
 
 
 def rotate_pdf(src: Path, dst: Path, degrees: int) -> None:
-    """Rotate every page relatively, in place, keeping document-level data."""
+    """
+    Rotate every page relatively on the opened document, not a rebuild, so Info,
+    XMP and outlines are kept. ``src`` is not modified.
+    """
     with pikepdf.open(src) as pdf:
         for page in pdf.pages:
             page.rotate(degrees, relative=True)
@@ -49,7 +52,8 @@ def rotate_pdf(src: Path, dst: Path, degrees: int) -> None:
 
 def remove_pages(src: Path, dst: Path, pages: Iterable[int]) -> None:
     """
-    Remove 1-indexed pages in place, keeping document-level data.
+    Remove 1-indexed pages from the opened document, not a rebuild, so Info, XMP
+    and outlines are kept. ``src`` is not modified.
 
     Duplicates are ignored. Pages are removed highest first so earlier removals
     never shift the index of later ones.

src/documents/tests/test_pdf_ops.py

@@ -27,6 +27,7 @@ SIGNED = SRC_ROOT / "paperless" / "tests" / "samples" / "tesseract" / "signed.pd
 
 def _page_fingerprint(page: pikepdf.Page) -> str:
     contents = page.obj.get("/Contents")
+    assert contents is not None, "sample page has no /Contents"
     streams = list(contents) if isinstance(contents, pikepdf.Array) else [contents]
     return hashlib.sha1(b"".join(s.read_bytes() for s in streams)).hexdigest()