Registry / web-framework / prettier-plugin-eex

prettier-plugin-eex

library0.6.0jsnpmunverified

A Prettier plugin that formats .html.eex and .html.leex files used in Elixir/Phoenix projects. Current stable version is 0.6.0. This plugin leverages Prettier's parsing and formatting capabilities to handle Elixir's EEx templates, preserving embedded Elixir expressions while formatting the surrounding HTML. It requires a minimum of Elixir 1.10 and Erlang OTP 22. Key differentiators include support for LiveView .leex files, configurable multiline expression formatting, and seamless integration with Phoenix projects via mix aliases. The plugin is actively maintained with regular bug fixes and breaking changes between major versions.

web-framework devops

npm install prettier-plugin-eex

github ↗package ↗

INSTALL

IMPORT

SIG · PRETTIER-PLUGIN-EE

prettier-plugin-eex

web-frameworkjavascriptv0.6.0

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

default

✓ // Automatically loaded by Prettier when placed in project root or in .prettierrc plugins

✗ import prettierPluginEex from 'prettier-plugin-eex'

No explicit import needed; Prettier auto-discovers plugins in node_modules or via plugins config.

Configuration in .prettierrc

✓ { "plugins": ["prettier-plugin-eex"], "overrides": [{"files": "*.html.eex", "options": { "parser": "html-eex" }}] }

✗ { "plugins": ["prettier-plugin-eex"], "parser": "html-eex" }

Set parser only in overrides for specific file extensions to avoid conflicts with other file types.

use with require

✓ const prettier = require('prettier'); prettier.format(code, { parser: 'html-eex', plugins: [require('prettier-plugin-eex')] });

✗ const prettierPluginEex = require('prettier-plugin-eex');

Plugin should be passed to prettier's format/check options, not used directly.

Installation and basic usage of prettier-plugin-eex: setting up .prettierrc, formatting EEx files via CLI and programmatic API.

// 1. Install // yarn add -D prettier prettier-plugin-eex // 2. Create .prettierrc.js in project root module.exports = { plugins: ['prettier-plugin-eex'], overrides: [ { files: ['*.html.eex', '*.html.leex'], options: { parser: 'html-eex', printWidth: 120, eexMultilineLineLength: 100, eexMultilineNoParens: ['link', 'form_for'] } } ] }; // 3. Format a file // npx prettier --write app/**/*.html.eex // 4. Or use programmatically const prettier = require('prettier'); const code = `<%= form_for @changeset, @action, fn f -> %>\n <%= text_input f, :name %>\n<% end %>`; const formatted = prettier.format(code, { parser: 'html-eex', plugins: [require('prettier-plugin-eex')], printWidth: 80 }); console.log(formatted);

Debug

Known issues

breakingMinimum Elixir version raised to 1.10 and Erlang OTP to 22 in v0.6.0.

fix

Update your Elixir to >=1.10 and Erlang OTP to >=22.

affects: >=0.6.0

breakingChanged from using 'embed' to 'print' function in v0.5.0 to fix error logging. Plugins relying on custom embed behavior may break.

fix

If you have a custom Prettier integration that relies on the embed method, update your code to work with the 'print' method.

affects: 0.4.0 to 0.5.0

breakingNon-zero exit status code returned when formatting errors occur (v0.5.0).

fix

Update CI scripts to expect non-zero exit on formatting errors.

affects: >=0.5.0

gotchaPlugin auto-discovery may not work if prettier is installed globally or in a different node_modules path. Common in Phoenix projects with assets directory.

fix

Set 'prettierPath' in VS Code settings to './assets/node_modules/prettier' or use explicit plugins array in .prettierrc with absolute/relative path.

affects: >=0.1.0

deprecatedNo deprecation warnings currently, but be aware that the plugin may require updating prettier peer dependency in future major versions.

fix

Keep an eye on releases and update prettier as needed.

affects: >=0.6.0

Errors

Common errors & fixes

Error: Cannot find module 'prettier-plugin-eex'

Plugin not installed or not in node_modules path where Prettier looks.

fix

Install the plugin: yarn add -D prettier prettier-plugin-eex. Ensure you are running prettier from the directory containing node_modules.

Error: No parser and no filepath given, couldn't infer a parser.

Prettier unable to determine parser for the file. Commonly occurs when using the plugin without specifying parser in overrides.

fix

Add an override in .prettierrc for *.html.eex files with parser: 'html-eex'.

TypeError: Cannot read properties of undefined (reading 'trim')

Plugin encounters malformed EEx expression or unsupported Elixir version.

fix

Check your Elixir version (>=1.10) and ensure the EEx templates are syntactically valid.

SyntaxError: Unexpected token (1:1)

File is not recognized as EEx/LEEx; possibly wrong file extension or misconfigured parser.

fix

Verify the file has .html.eex or .html.leex extension and your .prettierrc overrides match that pattern.

Upgrade

Version history

0.6.0latest on npm

Audit

Dependencies

prettierrequiredPeer dependency; the plugin requires Prettier to function.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/adamzapasnik/prettier-plugin-eex ↗

packagehttps://www.npmjs.com/package/prettier-plugin-eex ↗