hardhat-prettier

0.0.1 verified Sat Apr 25 auth: no javascript

Hardhat plugin integrating Prettier Solidity for automatic code formatting and style checking. Current stable version 0.0.1 (pre-release) with no regular release cadence — it's experimental. Key differentiators: adds a format task and overrides the check task for Solidity files, leveraging prettier-plugin-solidity's Solidity-specific formatting rules. Minimal configuration via .prettierrc. Requires Hardhat ^2.0.0, Prettier ^2.1.0, and prettier-plugin-solidity 1.0.0-beta.1. Alternatives like solhint focus on linting; this plugin focuses solely on formatting. Active development on GitHub by a single maintainer.

Common errors

error Error: Cannot find module 'hardhat-prettier' ↓

cause Plugin not installed or missing from dependencies

fix

Run: npm install hardhat-prettier

error Error HH12: Trying to use a non-existent hardhat task: format ↓

cause Plugin not imported in hardhat config

fix

Add require('hardhat-prettier') or import 'hardhat-prettier' to your hardhat.config.js/ts

error Cannot find module 'prettier-plugin-solidity' ↓

cause Missing peer dependency

fix

Install peer: npm install prettier-plugin-solidity

Warnings

deprecated prettier-plugin-solidity version pinned to 1.0.0-beta.1 — not semver-stable and may have breaking changes ↓

fix Monitor the package for updates; consider using a more recent version of prettier-plugin-solidity if compatible

gotcha Plugin overrides the 'check' task globally — affects all Hardhat check behavior ↓

fix Be aware that 'npx hardhat check' will now also check Solidity formatting; use 'npx hardhat format' to fix issues

gotcha No custom task configuration — uses .prettierrc defaults only ↓

fix Create a .prettierrc file for any customization; cannot pass options via hardhat.config

breaking Requires Hardhat ^2.0.0 — incompatible with Hardhat v1 ↓

fix Upgrade Hardhat to v2 or later

Install

npm install hardhat-prettier

yarn add hardhat-prettier

pnpm add hardhat-prettier

Imports

hardhat-prettier (plugin)
wrong
```
import { hardhatPrettier } from 'hardhat-prettier'
```
correct
```
import 'hardhat-prettier'
```
Plugin is imported for side effects — no named exports. Must be required/imported in hardhat.config
format task
wrong
```
npx hardhat prettier
```
correct
```
npx hardhat format
```
The plugin adds a 'format' task, not a 'prettier' task. Run via Hardhat CLI
check task (overridden)
wrong
```
npx hardhat check:format
```
correct
```
npx hardhat check
```
The plugin overrides the built-in 'check' task to include formatting verification

Quickstart

Shows how to install, configure, and use hardhat-prettier for formatting Solidity files in a Hardhat project.

// Install dependencies
// npm install hardhat-prettier prettier prettier-plugin-solidity

// hardhat.config.js
require('hardhat-prettier');

// hardhat.config.ts (TypeScript)
import 'hardhat-prettier';

// .prettierrc (optional, use default settings)
{
  "plugins": ["prettier-plugin-solidity"],
  "singleQuote": true,
  "printWidth": 120
}

// Format your Solidity files
// npx hardhat format

// Check formatting without overwriting (via check task)
// npx hardhat check