WilliamSmithEdward/pyOpenVBA

v1.0.1 Feature

This release adds 2 notable features for engineering teams evaluating rollout.

Published 12d Developer Productivity

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✓ No known CVEs patched in this version

Topics

compound-file deterministic excel file-format macro-extraction ms-cfb

+13 more

ms-ovba office-automation openxml pure-python python roundtrip vba vba-macros xlam xls xlsb xlsm zero-dependencies

Summary

AI summary

Fixed Excel rejection of multi‑chunk VBA modules and duplicate PROJECT entries after delete.

Changes in this release

Type	Severity	Summary	CVE
Feature
Feature	Low	Added demo/ folder with runnable end‑to‑end VBA module demo (`push_demo_module.py`, `test_macro_workbook.xlsm`, `demo.md`). Added demo/ folder with runnable end‑to‑end VBA module demo (`push_demo_module.py`, `test_macro_workbook.xlsm`, `demo.md`). Source: llm_adapter@2026-05-27 Confidence: high	—
Feature	Low	Added new regression tests for chunk compression and duplicate PROJECT handling. Added new regression tests for chunk compression and duplicate PROJECT handling. Source: llm_adapter@2026-05-27 Confidence: high	—
Feature	Low	Added `tests/live_excel_testing/large_vba_module.xlsm` fixture for multi‑chunk module validation. Added `tests/live_excel_testing/large_vba_module.xlsm` fixture for multi‑chunk module validation. Source: llm_adapter@2026-05-27 Confidence: high	—
Bugfix	Medium	Always emit token‑compressed chunks for VBA module source, fixing Excel rejection of multi‑chunk modules. Always emit token‑compressed chunks for VBA module source, fixing Excel rejection of multi‑chunk modules. Source: llm_adapter@2026-05-27 Confidence: high	—
Bugfix	Medium	Prevent duplicate `PROJECT` entries when re‑adding a deleted module, avoiding Excel corruption. Prevent duplicate `PROJECT` entries when re‑adding a deleted module, avoiding Excel corruption. Source: llm_adapter@2026-05-27 Confidence: high	—

Full changelog

Fixed

Excel rejected modules whose source spanned more than one 4 KB chunk with "An error occurred while loading ". The MS-OVBA compressor was emitting raw (CompressedChunkFlag = 0) chunks for full 4096-byte blocks. Although spec-legal, Office itself never writes raw chunks for module source streams -- empirically confirmed against an Excel-authored workbook containing a 16,881-byte module (all five of its chunks were token-compressed). The compressor now always emits token-compressed (flag = 1) chunks for module source; raw chunks remain only as a fallback for adversarial 4096-byte high-entropy input that overflows LZ encoding.
Re-running an add-module workflow after a delete produced duplicate PROJECT entries, which Excel treats as corruption. Calling add_module(name, ...) after delete_module(name) in the same save now cancels the pending delete and treats the operation as a source rewrite, matching Excel's own behaviour. serialize_project_stream additionally scrubs duplicate Module= and workspace declarations on every structural save, healing files that were corrupted by earlier versions.

Added

demo/ folder containing a runnable end-to-end demo (push_demo_module.py + test_macro_workbook.xlsm + demo.md).
New regression tests:
- TestCompress.test_full_chunk_emitted_as_token_compressed_not_raw and TestCompress.test_long_module_round_trip_through_excel_save verify that no raw chunks are produced for realistic VBA source.
- TestLargeModuleFixture uses an Excel-authored 16 KB module as an empirical anchor and round-trips it through pyOpenVBA's saver.
- test_delete_then_readd_same_name_does_not_duplicate_project_decl and test_save_heals_preexisting_duplicate_project_declarations cover the PROJECT-stream fix.
tests/live_excel_testing/large_vba_module.xlsm fixture (Excel-authored reference for multi-chunk module compression).

Full changelog: https://github.com/WilliamSmithEdward/pyOpenVBA/blob/main/docs/changelog.md
Compare: https://github.com/WilliamSmithEdward/pyOpenVBA/compare/v1.0.0...v1.0.1

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Earlier breaking changes

v3.0.0 Renamed the `AccessFile` class to `AccessReader`.
v3.0.0 Renamed `pyopenvba.access` module to `pyopenvba.access_read`.
v1.1.1 `add_module(kind=other)` now requires an explicit attribute header; automatic synthesis is disabled.