ExceLint is an Excel add-in that automatically finds formula errors in spreadsheets. It is a product of research from the PLASMA lab @ UMass Amherst and Microsoft Research.

by Dan Barowy (Williams College), Emery Berger (UMass Amherst / Microsoft Research), and Ben Zorn (Microsoft Research).

Talks on ExceLint

• ExceLint - Automatically Finding Spreadsheet Formula Errors, OOPSLA 2018 conference talk by Dan Barowy
• Saving the world from spreadsheets, Univ. of Washington PLSE seminar, by Emery Berger
• The next generation of developer tools for data programming, Microsoft Research Webinar Series, by Ben Zorn

Installation

ExceLint works as an add-in for all modern versions of Excel, including Mac, Windows, and online. You need to install the file manifest.xml following the appropriate instructions for each platform:

• Windows: https://docs.microsoft.com/en-us/office/dev/add-ins/testing/create-a-network-shared-folder-catalog-for-task-pane-and-content-add-ins
• on-line: https://docs.microsoft.com/en-us/office/dev/add-ins/testing/sideload-office-add-ins-for-testing
• Mac: https://docs.microsoft.com/en-us/office/dev/add-ins/testing/sideload-an-office-add-in-on-ipad-and-mac#sideload-an-add-in-in-office-on-mac

Source code

Source code for the add-in may be found at its GitHub repository.

Privacy

The ExceLint add-in does not collect personally identifiable information. See the privacy statement for more details.

Support

ExceLint is provided without any guarantee of support. However, we welcome bug reports and enhancement/feature requests.

Technical Details

The following technical paper describes how ExceLint works and includes an extensive empirical evaluation: ExceLint: Automatically Finding Spreadsheet Formula Errors, Daniel W. Barowy (Williams College), Emery D. Berger (University of Massachusetts Amherst), Benjamin Zorn (Microsoft Research). In Proceedings of the ACM on Programming Languages, Volume 2, Number OOPSLA.

Development

The ExceLint addin is written entirely in TypeScript. It is already set up to be hostable locally.

Requirements

To run ExceLint locally, you will first need to install Node and Git.

Running the ExceLint service locally

First, run the following commands to build and start the local ExceLint service (which just hosts the assets).

git clone https://github.com/plasma-umass/ExceLint-addin
cd ExceLint-addin
export NODE_OPTIONS=--no-experimental-fetch
npm install
npm run start-local

Testing

The easiest way to test the local service is to use Excel 365 (https://www.office.com/launch/excel?auth=2). Open a workbook, click the Insert menu, then click "Office Add-ins" on the ribbon. Click "Upload My Add-in" (in the upper-right hand corner), and select the file manifest-localhost.xml. If everything works as planned, you should see an icon for ExceLint on the Home ribbon. Click on it and it should open the task pane on the right-hand side of the window.

Acknowledgements

This material is based upon work supported by the National Science Foundation under Grant No. CCF-1617892. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.