elixcee

Run and test a practical subset of Excel VBA without Microsoft Excel. The core is Rust, with a Python API (PyO3), a standalone CLI, and an experimental @elixcee/xlsx JavaScript/WASM package.

Current release: 0.28.0.

elixcee is intended for data-processing macros. It is not a replacement for the Excel desktop application: UI features such as charts, dialogs, and screen updates are skipped, modeled, or reported according to the operation.

Install

pip install elixcee

Pre-built CLI binaries are published on the GitHub Releases page.

For a source build:

python3 -m venv .venv
source .venv/bin/activate
pip install maturin
maturin develop

CLI

elixcee <file.bas>... <MacroName> [--file input.xlsx] [--sheet Sheet1]
                         [--output result.xlsx] [--json]
elixcee check <file.bas>... [--entry MacroName] [--json]
elixcee snapshot <workbook.xlsx|ods> [--json]
elixcee test-workbook fixture.toml [--json] [--seed N] [--case N]
elixcee diagnose <file.bas>... <MacroName> --file input.xlsx [--json]
elixcee diagnose-workbook fixture.toml [--json] [--seed N] [--case N] [--cases N]

The run command accepts one or more standard VBA modules (.bas, .vbs, or .txt). Use Module.Sub for a qualified entry point in a multi-module run. --json emits one stable JSON object on stdout; see docs/agent-contract.md for the contract.

Python quick start

import elixcee

vm = elixcee.Vm()
vm.set_cell(1, 1, 10)          # coordinates are 1-based, like Excel
vm.run("""
Sub DoubleIt()
    Cells(1, 2).Value = Cells(1, 1).Value * 2
End Sub
""", "DoubleIt")
print(vm.get_cell(1, 2))       # 20

vm = elixcee.load_workbook("input.xlsx")
vm.run(vba_code, "ProcessData")
vm.save_workbook("output.xlsx")

The Python API also provides formula evaluation, ranges, sorting, merges, hidden rows/columns, sheet management, styles, tables, data validation, AutoFilter, defined-name inspection, pandas export, and .xlsx/.xlsm/.ods workbook I/O. See elixcee.pyi for signatures and behavior.

For large XLSX/XLSM files, open_stream(path, sheet=None) yields rows without materializing the whole workbook. Set include_row_numbers=True to receive (row_number, values) tuples, or max_rows=N/max_row_bytes=N/max_columns=N to bound a read. create_stream(path) provides an append-only XLSX row writer. Set max_rows=N and/or max_pending_bytes=N to bound pending output.

Vm(on_msgbox="skip") is the default. Use on_msgbox="error" to make a MsgBox call raise an error.

Supported VBA and formulas

The interpreter supports common data-processing constructs including Sub/Function, variables and arrays, If, For, For Each, Do, Select Case, With, On Error, user-defined types, named ranges, multiple sheets, and Excel-style Range/Cells operations. Formula support includes arithmetic, comparisons, criteria functions, lookup functions, date/time, text, statistical, financial, logical, and dynamic-array functions.

The maintained coverage list is FUNCTIONS.md. Unsupported or intentional no-op behavior is documented there and in the diagnostic contract.

Workbook compatibility

The Rust reader/writer preserves supported cell data, formulas, styles, merges, hidden rows/columns, and many unknown OOXML parts. Macro projects in .xlsm files are preserved during supported round trips. Features not modeled by the writer can still be lost or disconnected; tables, drawings, comments, hyperlinks, and other OOXML objects should be treated as compatibility gaps unless covered by tests for the version in use.

The project runs Rust tests, property tests, compatibility fixtures, and differential tests for the JavaScript package in CI. Compatibility with Excel's VBA execution semantics is not claimed for every macro, and post-save macro execution has not been fully validated against desktop Excel.

Development

cargo test --workspace
cargo fmt --check
cargo clippy --all-targets --all-features -- -D warnings

The short-term plan is in ROADMAP.md. Public design and policy documents are in docs/.

License: MIT. See THIRD_PARTY_NOTICES.md.