mo-fmt

library0.13.0jsnpmunverified

A standalone CLI tool for formatting Motoko source files, built on Prettier (v2.7) and the prettier-plugin-motoko plugin. Current stable version is 0.13.0, released by DFINITY. It offers a simple command-line interface for formatting .mo files in-place or checking format compliance. The tool can be installed globally via npm or used via npx; portable executables are also available for environments without Node.js. Compared to using the underlying Prettier plugin directly, mo-fmt provides a streamlined, zero-configuration experience for Motoko developers.

devops

npm install mo-fmt

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · MO-FMT

mo-fmt

devopsjavascriptv0.13.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

mo-fmt (CLI)

✓ npx mo-fmt **/*.mo

✗ npm run mo-fmt **/*.mo

The package is a CLI tool, not a library; use npx or global install. Common mistake: running via npm script without global install.

No programmatic API

✓ Uses CLI only; no programmatic import.

✗ import { fmt } from 'mo-fmt'

This package is a standalone CLI; there is no programmatic API. Use child_process.exec to invoke it programmatically.

Plugin usage

✓ Used via CLI; no direct plugin import.

✗ const plugin = require('mo-fmt')

The format plugin is provided by prettier-plugin-motoko, not mo-fmt. This package is a wrapper CLI.

Shows global installation and basic usage: formatting .mo files and checking format compliance.

# Install globally npm install -g mo-fmt # Format all .mo files in current directory recursively mo-fmt "**/*.mo" # Check formatting without modifying files mo-fmt -c "**/*.mo"

Debug

Known issues

gotchaGlob patterns may not expand correctly on Windows without quotes

fix

Use quotes around glob patterns: mo-fmt "**/*.mo"

affects: >=0.0.0

gotchamo-fmt expects Prettier v2.7 as a peer dependency; incompatible with Prettier v3

fix

Ensure prettier@^2.7 is installed alongside mo-fmt.

affects: >=0.0.0

gotchamo-fmt is a CLI tool only; no programmatic API available

fix

Use child_process.spawn or exec to invoke mo-fmt from Node.js scripts.

affects: >=0.0.0

Errors

Common errors & fixes

Error: Cannot find module 'prettier'

Peer dependency prettier not installed.

fix

Run 'npm install prettier@^2.7' in the same project.

bash: mo-fmt: command not found

mo-fmt not installed globally or not in PATH.

fix

Install globally with 'npm install -g mo-fmt' or use 'npx mo-fmt'.

Upgrade

Version history

0.13.0latest on npm

Audit

Dependencies

prettierrequiredPeer dependency required for formatting engine; mo-fmt relies on Prettier's core and the plugin.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/dfinity/prettier-plugin-motoko ↗

packagemo-fmt ↗

homepagehttps://github.com/dfinity/prettier-plugin-motoko/tree/main/package/mo-fmt#readme ↗