---
sidebar_position: 5
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# Contributing

Due to the precarious nature of the Open Specifications Promise, it is very
important to ensure code is cleanroom.  [Contribution Notes](https://git.sheetjs.com/sheetjs/sheetjs/src/branch/master/CONTRIBUTING.md)

<details>
  <summary><b>File organization</b> (click to show)</summary>

Folders:

| folder       | contents                                                      |
|:-------------|:--------------------------------------------------------------|
| `bin`        | server-side bin scripts (`xlsx.njs`)                          |
| `bits`       | raw source files that make up the final script                |
| `dist`       | dist files for web browsers and nonstandard JS environments   |
| `misc`       | miscellaneous supporting scripts                              |
| `modules`    | TypeScript source files that generate some of the bits        |
| `packages`   | Support libraries and tools                                   |
| `test_files` | test files (pulled from the test files repository)            |
| `tests`      | browser tests (run `make ctest` to rebuild)                   |
| `types`      | TypeScript definitions and tests                              |

</details>

After cloning the repo, running `make help` will display a list of commands.

## Setup

These instructions will cover system configuration, cloning the source repo,
building, reproducing official releases, and running NodeJS and browser tests.

:::note

These instructions were tested on the following platforms:

| Platform                      | Test Date  |
|:------------------------------|:-----------|
| Linux (Steam Deck Holo 3.4.6) | 2023-04-04 |
| Linux (Ubuntu 18.04 aarch64)  | 2023-04-13 |
| MacOS 10.13 (x64)             | 2023-04-04 |
| MacOS 13.0 (arm64)            | 2023-04-13 |
| Windows 10 (x64) + WSL Ubuntu | 2023-01-14 |
| Windows 11 (x64) + WSL Ubuntu | 2023-04-04 |

:::

### Install dependencies

#### OS-Specific Setup

import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';

<Tabs>
  <TabItem value="wsl" label="Windows WSL">

A) Ensure WSL ("WSL 2" in Windows 10) and the Ubuntu distribution are installed.

B) Install mercurial and subversion.

```bash
# Install support programs for the build and test commands
sudo add-apt-repository ppa:mercurial-ppa/releases
sudo apt-get update
sudo apt-get install mercurial subversion
sudo add-apt-repository --remove ppa:mercurial-ppa/releases
```

C) Install NodeJS

```bash
# Install bootstrap NodeJS and NPM within the WSL
curl -fsSL https://deb.nodesource.com/setup_16.x | sudo -E bash -
sudo apt-get install -y nodejs
```

Exit the WSL window and open a new one before proceeding:

```bash
# Switch to `n`-managed NodeJS
sudo npm i -g n
sudo n 16
```

D) Build and install a version of Git with proper SSL support:

```bash
# Git does not support OpenSSL out of the box, must do this
curl -LO https://github.com/paul-nelson-baker/git-openssl-shellscript/raw/main/compile-git-with-openssl.sh
chmod +x compile-git-with-openssl.sh
./compile-git-with-openssl.sh
```

E) Set `git` config `core.autocrlf` setting to `false`. The following commands
should be run twice, once within PowerShell and once within WSL bash:

```powershell
git config --global --add core.autocrlf false
git config --global --unset core.autocrlf true
```

  </TabItem>
  <TabItem value="osx" label="MacOS">

A) Run `git`. If Xcode or the command-line tools are not installed, you will be
asked to install.  Click "Install" and run through the steps.

B) Open a terminal window and install Homebrew:

```bash
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
```

C) Close the window, open a new terminal window, and disable analytics:

```bash
brew analytics off
```

To confirm analytics are disabled, run

```bash
brew analytics state
```

It should print `Analytics are disabled.`

D) Install Mercurial and Subversion:

```bash
brew install mercurial subversion
```

E) Install NodeJS

:::note

[The official NodeJS site](https://nodejs.org/en/download/) provides installers
for "LTS" and "Current" releases.  The "LTS" version should be installed.

Older versions of macOS are not compatible with newer versions of NodeJS. In
local testing, macOS 10.13 required NodeJS version `12.22.12`

:::

  </TabItem>
  <TabItem value="l" label="Linux">

A) Install `curl`, `mercurial`, `git`, and `subversion` using the system package
manager. On Debian and Ubuntu systems, `apt-get` installs packages:

```bash
sudo apt update
sudo apt-get install curl git mercurial subversion
```

Other Linux distributions may use other package managers.

<details open><summary><b>Steam Deck</b> (click to show)</summary>

Desktop Mode on the Steam Deck uses `pacman`.  It also requires a few steps.

0) Switch to Desktop mode and open `Konsole`

1) Set a password for the user by running `passwd` and following instructions.

2) Disable read-only mode:

```bash
sudo steamos-readonly disable
```

(When prompted, enter the password assigned in step 1)

3) Configure keyring:

```bash
sudo sh -c 'echo "keyserver hkps://keyserver.ubuntu.com" >> /etc/pacman.d/gnupg/gpg.conf'
sudo pacman-key --init
sudo pacman-key --populate
sudo pacman-key --refresh-keys
```

4) Install dependencies:

```bash
sudo pacman -S base-devel mercurial subversion
```

</details>

After installing mercurial and subversion, install NodeJS.

:::note

[The official NodeJS site](https://nodejs.org/en/download/) provides installers
for "LTS" and "Current" releases.  The "LTS" version should be installed.

After installing, if running `node` in the terminal fails with a `glibc` error,
an older version of NodeJS should be installed.  For example, Ubuntu 18.04 does
not support Node 18 support Node 16.20.0.

:::

  </TabItem>
</Tabs>

### Build from source tree

0) Clone the project:

```bash
git clone https://git.sheetjs.com/sheetjs/sheetjs
cd sheetjs
```

1) Install NodeJS modules for building the scripts

```bash
# Install dev dependencies
npm install

# Install global dependencies
sudo npm i -g mocha@2.5.3 voc @sheetjs/uglify-js
```

:::note Older Versions of Dependencies

Some of the dependencies are wildly out of date.  While SheetJS aims to run in
older versions of NodeJS and browsers, some libraries have chosen to break
backwards compatibility.  The specific versions are used because they are known
to work and known to produce consistent results.

:::

2) Initialize the test files:

```bash
make init
```

This step may take a while as it will be downloading a number of test files.

3) Run a short test, then run a build

```bash
# Short test
make test_misc

# Full Build
cd modules; make clean; make; cd ..
make dist

# Reset repo
git checkout -- .
```

### Reproduce official builds

4) Run `git log` and search for the commit that matches a particular release
version.  For example, version `0.19.3` can be found with:

```bash
git log | grep -B4 "version bump 0.19.3"
```

The output should look like:

```bash
$ git log | grep -B4 "version bump 0.19.3"
# highlight-next-line
commit 333e4e40f9c5603bd22a811f54c61c20bc9e17ab <-- this is the commit hash
Author: SheetJS <dev@sheetjs.com>
Date:   Mon Apr 17 23:39:28 2023 -0400

    version bump 0.19.3
```

5) Switch to that commit:

```bash
git checkout 333e4e40f9c5603bd22a811f54c61c20bc9e17ab
```

6) Run the full build sequence

```bash
make clean
cd modules; make clean; make; cd ..
make
make dist
```

7) To verify that the files are intact, use `md5sum` (`md5` on MacOS).

The local checksum for the browser script can be computed with:

```bash
$ md5sum dist/xlsx.full.min.js
f5c73b5ddc4b431c909d11c2e1d7a8e0  dist/xlsx.full.min.js
```

The checksum for the CDN version can be computed with:

```bash
$ curl -L https://cdn.sheetjs.com/xlsx-0.19.3/package/dist/xlsx.full.min.js | md5sum -
f5c73b5ddc4b431c909d11c2e1d7a8e0  -
```

The two hashes should match.

8) To return to the HEAD commit, run

```bash
git checkout master
```

### Test in web browsers

9) Start local server:

```bash
make ctestserv
```

The terminal will display a port number.  For example:

```
Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/)
```

10) Open a browser window and access `http://localhost:8000`, replacing `8000`
with the port number from the terminal window.

## Development

The `xlsx.js` and `xlsx.mjs` files are constructed from the files in the `bits`
subfolder. The build script (run `make`) will concatenate the individual bits
to produce the scripts.

To produce the dist files, run `make dist`.  The dist files are updated in each
version release and *should not be committed between versions*.

## Tests

The `test_misc` target runs the targeted feature tests.  It should take 5-10
seconds to perform feature tests without testing against the full test battery.
New features should be accompanied with tests for the relevant file formats.

For tests involving the read side, an appropriate feature test would involve
reading an existing file and checking the resulting workbook object.  If a
parameter is involved, files should be read with different values to verify that
the feature is working as expected.

For tests involving a new write feature which can already be parsed, appropriate
feature tests would involve writing a workbook with the feature and then opening
and verifying that the feature is preserved.

For tests involving a new write feature without an existing read ability, please
add a feature test to the kitchen sink `tests/write.js`.