ejs-lint

2.0.1 verified Fri May 01 auth: no javascript

Linter and syntax checker for EJS templates. Version 2.0.1 released September 2022. ESM-only since v2, requires Node 14+. Parses scriptlet and expression tags, replacing template output with whitespace to retain line/column numbers, then validates resulting JavaScript with acorn via node-syntax-error. Distinguishes itself from EJS core by providing meaningful syntax error messages with line context, supporting custom delimiters, CLI and API usage. Does not check for unclosed EJS tags but helps detect malformed scriptlets. Alternatives exist (e.g., eslint-plugin-ejs) but ejs-lint is the standalone, lightweight option.

Common errors

error Error [ERR_REQUIRE_ESM]: require() of ES Module not supported ↓

cause Using CommonJS require() on EJS-Lint v2+

fix

Switch to import or use dynamic import: const ejsLint = (await import('ejs-lint')).default;

error SyntaxError: Unexpected token (1:5) - line doesn't contain any scriptlets ↓

cause Forgot to close an EJS tag earlier in the template

fix

Double-check all <% and %> tags are properly closed.

Warnings

breaking v2.0.0 switched to ESM-only; CommonJS require() will fail ↓

fix Update code to use import statements or use dynamic import().

breaking v2.0.0 dropped Node 12 support; requires Node 14+ ↓

fix Upgrade Node.js to version 14 or higher.

breaking v1.0.0 removed deprecated .lint() alias; use ejsLint() instead ↓

fix Replace .lint(text, options) with ejsLint(text, options).

breaking v0.3.0 removed parse() method and --parse CLI option ↓

fix Use ejsLint() API or ejslint CLI only.

gotcha Does not detect unclosed EJS tags; will show confusing errors on lines without scriptlets ↓

fix Manually check for unclosed <% or %> before blaming the linter.

Install

npm install ejs-lint

yarn add ejs-lint

pnpm add ejs-lint

Imports

default
wrong
```
const ejsLint = require('ejs-lint')
```
correct
```
import ejsLint from 'ejs-lint'
```
ESM-only since v2; use dynamic import or upgrade to Node 14+.

cli

wrong

import { ejslint } from 'ejs-lint'

correct

import { execSync } from 'child_process'; execSync('npx ejslint file.ejs', {stdio: 'inherit'})

CLI is invoked via the 'ejslint' command, not as a programmatic export.

types

wrong

import type { EjsLintError } from 'ejs-lint'

correct

import type { SyntaxError } from 'node-syntax-error'

ejs-lint does not export its own error type; returns node-syntax-error objects.

Quickstart

Shows how to use the ejsLint API to check an EJS template for syntax errors.

import ejsLint from 'ejs-lint';

const template = `<% if (user) { %>
  <h1><%= user.name %></h1>
<% } else { %>
  <h1>No user</h1>
<% } %>`;

const err = ejsLint(template, { delimiter: '%' });
if (err) {
  console.error(`Syntax error at line ${err.line}, column ${err.column}: ${err.message}`);
} else {
  console.log('Template is valid');
}