Problem
Documents created with python-docx's doc.add_heading() render headings as unstyled body text in SuperDoc. The headings lose their font size, weight, and spacing.
Root Cause
doc.add_heading() creates paragraphs referencing Word's built-in heading styles (<w:pStyle w:val="Heading1"/>) without adding explicit <w:style> definitions in styles.xml. This is valid OOXML — Word has ~260 built-in styles that implicitly exist.
SuperDoc's style-engine (style-engine/src/ooxml/index.ts:283-284) returns {} when a styleId is not found in translatedLinkedStyles.styles, with no fallback to Word's built-in defaults. The existing test at index.test.ts:58-62 documents this: 'MissingStyle' silently returns empty.
The latentStyles element is parsed during import (super-converter/v3/handlers/w/latentStyles/) but is never used to provide fallback definitions.
Reproduction
from docx import Document
doc = Document()
doc.add_heading('Title', level=1) # Uses built-in Heading 1 style
doc.add_heading('Subtitle', level=2) # Uses built-in Heading 2 style
doc.add_paragraph('Body text')
doc.save('test.docx')Open test.docx in SuperDoc — all three lines render identically as body text.
Expected Behavior
- Heading 1: 26pt, bold, 12pt spacing before
- Heading 2: 20pt, bold, 8pt spacing before
- Body text: 11pt, normal weight
Per ECMA-376 §17.7.4.9, applications must provide built-in style defaults for standard style IDs when not explicitly defined in the document.
Suggested Fix
Add fallback logic in resolveStyleChain() at style-engine/src/ooxml/index.ts:283-284 to return Word's built-in heading properties when styleDef is undefined but styleId matches a known built-in pattern (Heading1–Heading9).
Problem
Documents created with python-docx's
doc.add_heading()render headings as unstyled body text in SuperDoc. The headings lose their font size, weight, and spacing.Root Cause
doc.add_heading()creates paragraphs referencing Word's built-in heading styles (<w:pStyle w:val="Heading1"/>) without adding explicit<w:style>definitions instyles.xml. This is valid OOXML — Word has ~260 built-in styles that implicitly exist.SuperDoc's style-engine (
style-engine/src/ooxml/index.ts:283-284) returns{}when astyleIdis not found intranslatedLinkedStyles.styles, with no fallback to Word's built-in defaults. The existing test atindex.test.ts:58-62documents this:'MissingStyle'silently returns empty.The
latentStyleselement is parsed during import (super-converter/v3/handlers/w/latentStyles/) but is never used to provide fallback definitions.Reproduction
Open
test.docxin SuperDoc — all three lines render identically as body text.Expected Behavior
Per ECMA-376 §17.7.4.9, applications must provide built-in style defaults for standard style IDs when not explicitly defined in the document.
Suggested Fix
Add fallback logic in
resolveStyleChain()atstyle-engine/src/ooxml/index.ts:283-284to return Word's built-in heading properties whenstyleDefis undefined butstyleIdmatches a known built-in pattern (Heading1–Heading9).