Update docx, pptx, and xlsx skills (#1447)

Add support for template formats (.dotx, .potx, .xltx) across validation
and the helper scripts.

Consolidate the shared office helpers into a single module, replacing the
pack/unpack pipeline with explicit zip/unzip steps. Extraction now rejects
symlink and path-traversal archive entries. Move run merging to a
standalone docx script, since it only ever applied to Word documents.

Fix the redlining validator so it compares against the original even when
a document has no tracked changes, which is when an untracked edit would
otherwise go unreported.

Provision a LibreOffice user profile per invocation so conversions work in
sandboxed environments.

Trim the skill docs to the guidance that earns its place.
This commit is contained in:
Peter Lai
2026-07-16 19:47:37 -07:00
committed by GitHub
parent 9d2f1ae187
commit fa0fa64bdc
53 changed files with 4147 additions and 4442 deletions
@@ -0,0 +1,111 @@
import os
import posixpath
import re
import stat
import tempfile
import urllib.parse
import zipfile
from pathlib import Path
OOXML_FAMILY = {
".docx": "docx",
".dotx": "docx",
".pptx": "pptx",
".potx": "pptx",
".xlsx": "xlsx",
".xltx": "xlsx",
}
_SCHEME_RE = re.compile(r"^[A-Za-z][A-Za-z0-9+.\-]*:")
SLIDE_REL_TYPE = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/slide"
def opc_target(target: str, source_part: str, target_mode: str = "") -> str | None:
if not target:
return None
if target_mode.lower() == "external":
return None
if _SCHEME_RE.match(target):
return None
target = urllib.parse.unquote(target)
if "\\" in target:
raise ValueError(f"relationship target is not a POSIX part name: {target!r}")
if target.startswith("/"):
joined = target.lstrip("/")
else:
joined = posixpath.join(posixpath.dirname(source_part), target)
parts: list[str] = []
for segment in posixpath.normpath(joined).split("/"):
if segment in ("", "."):
continue
if segment == "..":
if not parts:
raise ValueError(f"relationship target escapes the package: {target!r}")
parts.pop()
else:
parts.append(segment)
if not parts:
raise ValueError(f"relationship target resolves to nothing: {target!r}")
return "/".join(parts)
def rels_source_part(rels_file: Path, unpacked_dir: Path) -> str:
owner_dir = rels_file.parent.parent.relative_to(unpacked_dir)
return posixpath.join(owner_dir.as_posix(), rels_file.name[: -len(".rels")]).lstrip("./")
def part_text(data: bytes) -> str:
return data.decode("utf-8", "surrogateescape")
XML_SPACE = " \t\r\n"
def rendered_text(text: str, preserve: bool) -> str:
return text if preserve else text.strip(XML_SPACE)
def safe_extract(zf: zipfile.ZipFile, dest: Path) -> None:
dest = dest.resolve()
for m in zf.infolist():
if stat.S_ISLNK(m.external_attr >> 16):
raise ValueError(f"symlink archive entry not allowed: {m.filename!r}")
target = (dest / m.filename).resolve()
if not target.is_relative_to(dest):
raise ValueError(f"unsafe archive entry: {m.filename!r}")
zf.extract(m, dest)
def rezip(src_dir: Path, out_path: Path) -> None:
files = sorted(p for p in src_dir.rglob("*") if p.is_file())
ct = src_dir / "[Content_Types].xml"
fd, tmp_name = tempfile.mkstemp(
prefix=out_path.name + ".", suffix=".tmp", dir=out_path.parent
)
tmp_out = Path(tmp_name)
try:
with os.fdopen(fd, "wb") as fh:
with zipfile.ZipFile(fh, "w", zipfile.ZIP_DEFLATED) as zf:
if ct.exists():
zf.write(ct, ct.relative_to(src_dir), compress_type=zipfile.ZIP_STORED)
for f in files:
if f == ct:
continue
zf.write(f, f.relative_to(src_dir))
if out_path.exists():
mode = out_path.stat().st_mode & 0o777
else:
umask = os.umask(0)
os.umask(umask)
mode = 0o666 & ~umask
os.chmod(tmp_out, mode)
os.replace(tmp_out, out_path)
finally:
if tmp_out.exists():
tmp_out.unlink()
@@ -1,199 +0,0 @@
"""Merge adjacent runs with identical formatting in DOCX.
Merges adjacent <w:r> elements that have identical <w:rPr> properties.
Works on runs in paragraphs and inside tracked changes (<w:ins>, <w:del>).
Also:
- Removes rsid attributes from runs (revision metadata that doesn't affect rendering)
- Removes proofErr elements (spell/grammar markers that block merging)
"""
from pathlib import Path
import defusedxml.minidom
def merge_runs(input_dir: str) -> tuple[int, str]:
doc_xml = Path(input_dir) / "word" / "document.xml"
if not doc_xml.exists():
return 0, f"Error: {doc_xml} not found"
try:
dom = defusedxml.minidom.parseString(doc_xml.read_text(encoding="utf-8"))
root = dom.documentElement
_remove_elements(root, "proofErr")
_strip_run_rsid_attrs(root)
containers = {run.parentNode for run in _find_elements(root, "r")}
merge_count = 0
for container in containers:
merge_count += _merge_runs_in(container)
doc_xml.write_bytes(dom.toxml(encoding="UTF-8"))
return merge_count, f"Merged {merge_count} runs"
except Exception as e:
return 0, f"Error: {e}"
def _find_elements(root, tag: str) -> list:
results = []
def traverse(node):
if node.nodeType == node.ELEMENT_NODE:
name = node.localName or node.tagName
if name == tag or name.endswith(f":{tag}"):
results.append(node)
for child in node.childNodes:
traverse(child)
traverse(root)
return results
def _get_child(parent, tag: str):
for child in parent.childNodes:
if child.nodeType == child.ELEMENT_NODE:
name = child.localName or child.tagName
if name == tag or name.endswith(f":{tag}"):
return child
return None
def _get_children(parent, tag: str) -> list:
results = []
for child in parent.childNodes:
if child.nodeType == child.ELEMENT_NODE:
name = child.localName or child.tagName
if name == tag or name.endswith(f":{tag}"):
results.append(child)
return results
def _is_adjacent(elem1, elem2) -> bool:
node = elem1.nextSibling
while node:
if node == elem2:
return True
if node.nodeType == node.ELEMENT_NODE:
return False
if node.nodeType == node.TEXT_NODE and node.data.strip():
return False
node = node.nextSibling
return False
def _remove_elements(root, tag: str):
for elem in _find_elements(root, tag):
if elem.parentNode:
elem.parentNode.removeChild(elem)
def _strip_run_rsid_attrs(root):
for run in _find_elements(root, "r"):
for attr in list(run.attributes.values()):
if "rsid" in attr.name.lower():
run.removeAttribute(attr.name)
def _merge_runs_in(container) -> int:
merge_count = 0
run = _first_child_run(container)
while run:
while True:
next_elem = _next_element_sibling(run)
if next_elem and _is_run(next_elem) and _can_merge(run, next_elem):
_merge_run_content(run, next_elem)
container.removeChild(next_elem)
merge_count += 1
else:
break
_consolidate_text(run)
run = _next_sibling_run(run)
return merge_count
def _first_child_run(container):
for child in container.childNodes:
if child.nodeType == child.ELEMENT_NODE and _is_run(child):
return child
return None
def _next_element_sibling(node):
sibling = node.nextSibling
while sibling:
if sibling.nodeType == sibling.ELEMENT_NODE:
return sibling
sibling = sibling.nextSibling
return None
def _next_sibling_run(node):
sibling = node.nextSibling
while sibling:
if sibling.nodeType == sibling.ELEMENT_NODE:
if _is_run(sibling):
return sibling
sibling = sibling.nextSibling
return None
def _is_run(node) -> bool:
name = node.localName or node.tagName
return name == "r" or name.endswith(":r")
def _can_merge(run1, run2) -> bool:
rpr1 = _get_child(run1, "rPr")
rpr2 = _get_child(run2, "rPr")
if (rpr1 is None) != (rpr2 is None):
return False
if rpr1 is None:
return True
return rpr1.toxml() == rpr2.toxml()
def _merge_run_content(target, source):
for child in list(source.childNodes):
if child.nodeType == child.ELEMENT_NODE:
name = child.localName or child.tagName
if name != "rPr" and not name.endswith(":rPr"):
target.appendChild(child)
def _consolidate_text(run):
t_elements = _get_children(run, "t")
for i in range(len(t_elements) - 1, 0, -1):
curr, prev = t_elements[i], t_elements[i - 1]
if _is_adjacent(prev, curr):
prev_text = prev.firstChild.data if prev.firstChild else ""
curr_text = curr.firstChild.data if curr.firstChild else ""
merged = prev_text + curr_text
if prev.firstChild:
prev.firstChild.data = merged
else:
prev.appendChild(run.ownerDocument.createTextNode(merged))
if merged.startswith(" ") or merged.endswith(" "):
prev.setAttribute("xml:space", "preserve")
elif prev.hasAttribute("xml:space"):
prev.removeAttribute("xml:space")
run.removeChild(curr)
@@ -0,0 +1,170 @@
"""Find chart XML that PowerPoint refuses but the schema accepts.
Detection only: for either fault more than one repair is valid, and only the
author knows which was meant.
"""
from __future__ import annotations
import re
from typing import Mapping
from . import part_text
_CHART_PART_RE = re.compile(r"ppt/charts/chart\d+\.xml")
_GROUPING_RE = re.compile(r"""<c:grouping\b[^>]*?\bval=["'](\w+)["']""")
_DLBL_POS_RE = re.compile(r"""<c:dLblPos\b[^>]*?\bval=["'](\w+)["']""")
def _strip_ext_lst(text: str) -> str:
out, cursor = [], 0
for lo, hi in _ext_lst_spans(text):
out.append(text[cursor:lo])
cursor = hi
out.append(text[cursor:])
return "".join(out)
_BAR_GROUP_RE = re.compile(r"<c:(bar3DChart|barChart)\b[^>]*(?<!/)>.*?</c:\1\s*>", re.DOTALL)
STACKED_GROUPINGS = frozenset({"stacked", "percentStacked"})
ILLEGAL_ON_STACKED = frozenset({"outEnd"})
LEGAL_ON_STACKED = ("ctr", "inEnd", "inBase")
def _check_stacked_label_positions(part: str, xml: str) -> list[str]:
problems: list[str] = []
for match in _BAR_GROUP_RE.finditer(xml):
block = _strip_ext_lst(match.group(0))
group = match.group(1)
grouping = _GROUPING_RE.search(block)
if grouping is None or grouping.group(1) not in STACKED_GROUPINGS:
continue
bad = [p for p in _DLBL_POS_RE.findall(block) if p in ILLEGAL_ON_STACKED]
for pos in sorted(set(bad)):
problems.append(
f'{part}: {bad.count(pos)} data label(s) use dLblPos="{pos}" on a '
f"{grouping.group(1)} {group}; PowerPoint allows only "
f"{', '.join(LEGAL_ON_STACKED)} there"
)
return problems
_ANY_CHART_GROUP_RE = re.compile(r"<c:(\w+Chart)\b[^>]*(?<!/)>.*?</c:\1\s*>", re.DOTALL)
_AXID_RE = re.compile(
r"""\s*<c:axId\b[^>]*?\bval=["'](-?\d+)["']\s*(?:/>|>\s*</c:axId\s*>)"""
)
_AXIS_DECL_RE = re.compile(
r"""<c:(catAx|valAx|serAx|dateAx)\b[^>]*(?<!/)>\s*<c:axId\b[^>]*?\bval=["'](-?\d+)["']"""
)
AXID_LIMIT = {
"barChart": 2, "lineChart": 2, "areaChart": 2, "scatterChart": 2,
"bubbleChart": 2, "radarChart": 2, "stockChart": 2,
"bar3DChart": 3, "line3DChart": 3, "area3DChart": 3,
"surfaceChart": 3, "surface3DChart": 3,
}
AXID_MINIMUM = {
"barChart": 2, "lineChart": 2, "areaChart": 2, "scatterChart": 2,
"bubbleChart": 2, "radarChart": 2, "stockChart": 2,
"bar3DChart": 2, "area3DChart": 2, "surfaceChart": 2,
"line3DChart": 3, "surface3DChart": 3,
}
def _declared_axes(xml: str) -> dict[str, list[str]]:
axes: dict[str, list[str]] = {}
for kind, axid in _AXIS_DECL_RE.findall(xml):
axes.setdefault(kind, []).append(axid)
return axes
def _canonical_ids(axes: dict[str, list[str]], limit: int) -> list[str] | None:
category = axes.get("catAx", []) + axes.get("dateAx", [])
value = axes.get("valAx", [])
series = axes.get("serAx", [])
if len(category) != 1 or len(value) != 1 or len(series) > 1:
return None
ids = [category[0], value[0]]
if limit >= 3 and series:
ids.append(series[0])
return ids
def _undeclared_axes(kind: str, block: str, axes: dict[str, list[str]]) -> list[str] | None:
if kind not in AXID_LIMIT:
return None
ids = _AXID_RE.findall(block)
declared = {i for group in axes.values() for i in group}
if len([i for i in ids if i in declared]) >= 2:
return None
return ids
def _check_chart_axis_references(part: str, xml: str) -> list[str]:
axes = _declared_axes(xml)
problems: list[str] = []
declared = {i for group in axes.values() for i in group}
for match in _ANY_CHART_GROUP_RE.finditer(xml):
kind, block = match.group(1), match.group(0)
ids = _undeclared_axes(kind, block, axes)
if ids is None:
continue
if not ids:
problems.append(
f"{part}: <c:{kind}> declares no <c:axId> this part can resolve; a chart "
f"group needs {AXID_MINIMUM[kind]}, and PowerPoint discards one with fewer"
)
continue
dead = [i for i in ids if i not in declared]
canonical = _canonical_ids(axes, AXID_LIMIT[kind])
if canonical is not None and len(canonical) >= AXID_MINIMUM[kind]:
hint = f"Fix: point them at the axes this part declares ({', '.join(canonical)})"
else:
hint = ("Fix: the part declares several axes of a kind -- declare the "
"secondary axes the series expects, or drop them")
detail = (f"of which {', '.join(dead)} name no declared axis"
if dead else f"only {len(ids)} of which this part declares")
problems.append(
f"{part}: <c:{kind}> references axId {', '.join(ids)}, {detail}, "
f"leaving fewer than two live axes; PowerPoint discards the chart. {hint}"
)
return problems
def _ext_lst_spans(text: str) -> list[tuple[int, int]]:
spans: list[tuple[int, int]] = []
depth = 0
start = 0
for match in re.finditer(r"<(/?)c:extLst\b[^>]*?(/?)>", text):
closing, self_closing = match.group(1), match.group(2)
if self_closing:
continue
if closing:
depth -= 1
if depth == 0:
spans.append((start, match.end()))
else:
if depth == 0:
start = match.start()
depth += 1
return spans
CHART_CHECKS = (_check_stacked_label_positions, _check_chart_axis_references)
def find_chart_problems(files: Mapping[str, bytes]) -> list[str]:
problems: list[str] = []
for part in sorted(n for n in files if _CHART_PART_RE.fullmatch(n)):
xml = part_text(files[part])
for check in CHART_CHECKS:
problems.extend(check(part, xml))
return problems
@@ -0,0 +1,60 @@
"""Pick the slide-XML schema errors PowerPoint refuses the file over.
A denylist over lxml's messages, so an unrecognised error class is a miss rather
than a false alarm.
"""
from __future__ import annotations
import re
SLIDE_PART_RE = re.compile(
r"ppt/(slides|slideLayouts|slideMasters|notesSlides|notesMasters|handoutMasters)"
r"/[^/]+\.xml"
)
FATAL_SLIDE_ERRORS: tuple[tuple[re.Pattern[str], str], ...] = (
(
re.compile(r"\}tableStyleId': This element is not expected"),
"two <a:tableStyleId> in one <a:tblPr> (the schema allows one)",
),
(
re.compile(r"\}srgbClr', attribute 'val'"),
"a colour that is not six hex digits",
),
(
re.compile(r"\}txBody': Missing child element"),
"a <p:txBody> with no children",
),
(
re.compile(r"\}miter', attribute 'lim'"),
'a line join with lim="NaN"',
),
(
re.compile(r"\}uLnTx': This element is not expected"),
"<a:uLnTx> in a position the schema forbids",
),
(
re.compile(r"\}overrideClrMapping': This element is not expected"),
"<p:overrideClrMapping> in a position the schema forbids",
),
(
re.compile(r"\}nvGrpSpPr': Missing child element"),
"a <p:nvGrpSpPr> with no children",
),
)
def is_schema_verdict(error: str) -> bool:
return error.startswith("Element ")
def fatal_slide_errors(errors: set[str]) -> list[str]:
out = []
for error in sorted(errors):
for pattern, meaning in FATAL_SLIDE_ERRORS:
if pattern.search(error):
out.append(f"{meaning}: {error}")
break
return out
@@ -0,0 +1,114 @@
"""Find masters sharing a theme part in the way PowerPoint refuses to open.
Reports only; the fix is to move <p:notesMasterIdLst> back to directly after
<p:sldIdLst> in ppt/presentation.xml.
"""
from __future__ import annotations
import posixpath
import re
from typing import Mapping
from . import part_text
THEME_REL_TYPE = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/theme"
_MASTER_RE = re.compile(
r"^ppt/(?P<group>slideMasters|notesMasters|handoutMasters)/"
r"(?:slide|notes|handout)Master(?P<num>\d+)\.xml$"
)
_GROUP_ORDER = {"slideMasters": 0, "notesMasters": 1, "handoutMasters": 2}
_RELATIONSHIP_RE = re.compile(
r"<Relationship\b[^>]*?(?:/>|>.*?</Relationship\s*>)", re.DOTALL
)
def _sort_key(name: str) -> tuple[int, int]:
m = _MASTER_RE.match(name)
assert m is not None
return (_GROUP_ORDER[m.group("group")], int(m.group("num")))
def _rels_path(part: str) -> str:
directory, base = posixpath.split(part)
return f"{directory}/_rels/{base}.rels"
def _resolve(rels_path: str, target: str) -> str:
if target.startswith("/"):
return target.lstrip("/")
part_dir = posixpath.dirname(posixpath.dirname(rels_path))
return posixpath.normpath(posixpath.join(part_dir, target))
def _theme_rel(files: Mapping[str, bytes], master: str):
rels_path = _rels_path(master)
rels = files.get(rels_path)
if rels is None:
return None
for element in _RELATIONSHIP_RE.findall(part_text(rels)):
if f'Type="{THEME_REL_TYPE}"' not in element:
continue
target = re.search(r'\bTarget="([^"]+)"', element)
if target is None:
continue
return rels_path, element, _resolve(rels_path, target.group(1))
return None
def _masters(files: Mapping[str, bytes]) -> list[str]:
return sorted((n for n in files if _MASTER_RE.match(n)), key=_sort_key)
_PRESENTATION = "ppt/presentation.xml"
_NOTES_MASTERS = "ppt/notesMasters/"
_IGNORABLE_RE = re.compile(r"<!--.*?-->|<\?.*?\?>", re.DOTALL)
_AFTER_SLDIDLST_RE = re.compile(
r"<p:sldIdLst\b(?:[^>]*/>|[^>]*>.*?</p:sldIdLst\s*>)\s*(<[^>\s/]+)", re.DOTALL
)
def _notes_master_share_is_inert(files: Mapping[str, bytes]) -> bool:
data = files.get(_PRESENTATION)
if data is None:
return False
match = _AFTER_SLDIDLST_RE.search(_IGNORABLE_RE.sub("", part_text(data)))
return match is not None and match.group(1) == "<p:notesMasterIdLst"
def _shares(files: Mapping[str, bytes]):
owner: dict[str, str] = {}
for master in _masters(files):
found = _theme_rel(files, master)
if found is None:
continue
rels_path, element, theme = found
if theme not in files:
continue
if theme in owner:
yield master, rels_path, element, theme, owner[theme]
else:
owner[theme] = master
def _is_inert(master: str, inert_notes: bool) -> bool:
return inert_notes and master.startswith(_NOTES_MASTERS)
def find_shared_master_themes(files: Mapping[str, bytes]) -> list[str]:
return [
f"{master} shares {theme} with {first}"
for master, _, _, theme, first in _shares(files)
]
def live_shared_master_themes(files: Mapping[str, bytes]) -> list[str]:
inert_notes = _notes_master_share_is_inert(files)
return [
f"{master} shares {theme} with {first}"
for master, _, _, theme, first in _shares(files)
if not _is_inert(master, inert_notes)
]
@@ -1,197 +0,0 @@
"""Simplify tracked changes by merging adjacent w:ins or w:del elements.
Merges adjacent <w:ins> elements from the same author into a single element.
Same for <w:del> elements. This makes heavily-redlined documents easier to
work with by reducing the number of tracked change wrappers.
Rules:
- Only merges w:ins with w:ins, w:del with w:del (same element type)
- Only merges if same author (ignores timestamp differences)
- Only merges if truly adjacent (only whitespace between them)
"""
import xml.etree.ElementTree as ET
import zipfile
from pathlib import Path
import defusedxml.minidom
WORD_NS = "http://schemas.openxmlformats.org/wordprocessingml/2006/main"
def simplify_redlines(input_dir: str) -> tuple[int, str]:
doc_xml = Path(input_dir) / "word" / "document.xml"
if not doc_xml.exists():
return 0, f"Error: {doc_xml} not found"
try:
dom = defusedxml.minidom.parseString(doc_xml.read_text(encoding="utf-8"))
root = dom.documentElement
merge_count = 0
containers = _find_elements(root, "p") + _find_elements(root, "tc")
for container in containers:
merge_count += _merge_tracked_changes_in(container, "ins")
merge_count += _merge_tracked_changes_in(container, "del")
doc_xml.write_bytes(dom.toxml(encoding="UTF-8"))
return merge_count, f"Simplified {merge_count} tracked changes"
except Exception as e:
return 0, f"Error: {e}"
def _merge_tracked_changes_in(container, tag: str) -> int:
merge_count = 0
tracked = [
child
for child in container.childNodes
if child.nodeType == child.ELEMENT_NODE and _is_element(child, tag)
]
if len(tracked) < 2:
return 0
i = 0
while i < len(tracked) - 1:
curr = tracked[i]
next_elem = tracked[i + 1]
if _can_merge_tracked(curr, next_elem):
_merge_tracked_content(curr, next_elem)
container.removeChild(next_elem)
tracked.pop(i + 1)
merge_count += 1
else:
i += 1
return merge_count
def _is_element(node, tag: str) -> bool:
name = node.localName or node.tagName
return name == tag or name.endswith(f":{tag}")
def _get_author(elem) -> str:
author = elem.getAttribute("w:author")
if not author:
for attr in elem.attributes.values():
if attr.localName == "author" or attr.name.endswith(":author"):
return attr.value
return author
def _can_merge_tracked(elem1, elem2) -> bool:
if _get_author(elem1) != _get_author(elem2):
return False
node = elem1.nextSibling
while node and node != elem2:
if node.nodeType == node.ELEMENT_NODE:
return False
if node.nodeType == node.TEXT_NODE and node.data.strip():
return False
node = node.nextSibling
return True
def _merge_tracked_content(target, source):
while source.firstChild:
child = source.firstChild
source.removeChild(child)
target.appendChild(child)
def _find_elements(root, tag: str) -> list:
results = []
def traverse(node):
if node.nodeType == node.ELEMENT_NODE:
name = node.localName or node.tagName
if name == tag or name.endswith(f":{tag}"):
results.append(node)
for child in node.childNodes:
traverse(child)
traverse(root)
return results
def get_tracked_change_authors(doc_xml_path: Path) -> dict[str, int]:
if not doc_xml_path.exists():
return {}
try:
tree = ET.parse(doc_xml_path)
root = tree.getroot()
except ET.ParseError:
return {}
namespaces = {"w": WORD_NS}
author_attr = f"{{{WORD_NS}}}author"
authors: dict[str, int] = {}
for tag in ["ins", "del"]:
for elem in root.findall(f".//w:{tag}", namespaces):
author = elem.get(author_attr)
if author:
authors[author] = authors.get(author, 0) + 1
return authors
def _get_authors_from_docx(docx_path: Path) -> dict[str, int]:
try:
with zipfile.ZipFile(docx_path, "r") as zf:
if "word/document.xml" not in zf.namelist():
return {}
with zf.open("word/document.xml") as f:
tree = ET.parse(f)
root = tree.getroot()
namespaces = {"w": WORD_NS}
author_attr = f"{{{WORD_NS}}}author"
authors: dict[str, int] = {}
for tag in ["ins", "del"]:
for elem in root.findall(f".//w:{tag}", namespaces):
author = elem.get(author_attr)
if author:
authors[author] = authors.get(author, 0) + 1
return authors
except (zipfile.BadZipFile, ET.ParseError):
return {}
def infer_author(modified_dir: Path, original_docx: Path, default: str = "Claude") -> str:
modified_xml = modified_dir / "word" / "document.xml"
modified_authors = get_tracked_change_authors(modified_xml)
if not modified_authors:
return default
original_authors = _get_authors_from_docx(original_docx)
new_changes: dict[str, int] = {}
for author, count in modified_authors.items():
original_count = original_authors.get(author, 0)
diff = count - original_count
if diff > 0:
new_changes[author] = diff
if not new_changes:
return default
if len(new_changes) == 1:
return next(iter(new_changes))
raise ValueError(
f"Multiple authors added new changes: {new_changes}. "
"Cannot infer which author to validate."
)