Editor: Switch from Esprima to Espree for JavaScript validation.

westonruter · gemini-code-assist[bot] · westonruter · commit ee2b6bdb7d89 · 2026-01-23T00:07:57.000-08:00
Replaces the outdated `esprima` parser with `espree` to provide support for modern JavaScript (ES6+) validation in the code editor. A new `espree` script handle is registered, and the `fakejshint` wrapper is updated to use it while maintaining the `esprima` handle for backward compatibility.

- Adds `espree` to `package.json`.
- Creates `tools/vendors/espree-entry.js` and adds a new Webpack entry point to bundle `espree`.
- Updates `fakejshint.js` to utilize `window.espree.parse` with ES6+ support.
- Registers `espree` in `script-loader.php` and updates `jshint` handle dependencies.
- Updates PHPUnit test data provider to include `espree`.

Co-authored-by: gemini-code-assist[bot] &lt;176961590+gemini-code-assist[bot]@users.noreply.github.com&gt;
diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -79,6 +79,7 @@
 		"core-js-url-browser": "3.6.4",
 		"csslint": "1.0.5",
 		"element-closest": "3.0.2",
+		"espree": "9.6.1",
 		"esprima": "4.0.1",
 		"formdata-polyfill": "4.0.10",
 		"hoverintent": "2.2.1",
diff --git a/src/js/_enqueues/vendor/codemirror/fakejshint.js b/src/js/_enqueues/vendor/codemirror/fakejshint.js
@@ -1,4 +1,4 @@
-// JSHINT has some GPL Compatability issues, so we are faking it out and using esprima for validation
+// JSHINT has some GPL Compatability issues, so we are faking it out and using espree for validation
 // Based on https://github.com/jquery/esprima/blob/gh-pages/demo/validate.js which is MIT licensed
 
 var fakeJSHINT = new function() {
@@ -15,9 +15,13 @@ var fakeJSHINT = new function() {
 	};
 	this.parse = function( code ){
 		try {
-			syntax = window.esprima.parse(code, { tolerant: true, loc: true });
+			syntax = window.espree.parse(code, {
+				ecmaVersion: 'latest',
+				loc: true,
+				sourceType: 'module'
+			});
 			errors = syntax.errors;
-			if ( errors.length > 0 ) {
+			if ( errors && errors.length > 0 ) {
 				for ( var i = 0; i < errors.length; i++) {
 					var error = errors[i];
 					that.data.push( that.convertError( error ) );
diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
@@ -1197,8 +1197,9 @@ function wp_default_scripts( $scripts ) {
 
 	$scripts->add( 'wp-codemirror', '/wp-includes/js/codemirror/codemirror.min.js', array(), '5.65.20' );
 	$scripts->add( 'csslint', '/wp-includes/js/codemirror/csslint.js', array(), '1.0.5' );
-	$scripts->add( 'esprima', '/wp-includes/js/codemirror/esprima.js', array(), '4.0.1' );
-	$scripts->add( 'jshint', '/wp-includes/js/codemirror/fakejshint.js', array( 'esprima' ), '2.9.5' );
+	$scripts->add( 'esprima', '/wp-includes/js/codemirror/esprima.js', array(), '4.0.1' ); // Deprecated. Use 'espree' instead.
+	$scripts->add( 'espree', '/wp-includes/js/codemirror/espree.min.js', array(), '9.6.1' );
+	$scripts->add( 'jshint', '/wp-includes/js/codemirror/fakejshint.js', array( 'espree' ), '2.9.5' );
 	$scripts->add( 'jsonlint', '/wp-includes/js/codemirror/jsonlint.js', array(), '1.6.3' );
 	$scripts->add( 'htmlhint', '/wp-includes/js/codemirror/htmlhint.js', array(), '1.8.0' );
 	$scripts->add( 'htmlhint-kses', '/wp-includes/js/codemirror/htmlhint-kses.js', array( 'htmlhint' ) );
diff --git a/tests/phpunit/tests/dependencies/scripts.php b/tests/phpunit/tests/dependencies/scripts.php
@@ -3859,6 +3859,7 @@ public function data_vendor_script_versions_registered_manually() {
 			'csslint'                          => array( 'csslint' ),
 			'element-closest'                  => array( 'element-closest', 'wp-polyfill-element-closest' ),
 			'esprima'                          => array( 'esprima' ),
+			'espree'                           => array( 'espree' ),
 			'formdata-polyfill'                => array( 'formdata-polyfill', 'wp-polyfill-formdata' ),
 			'imagesloaded'                     => array( 'imagesloaded' ),
 			'jquery-color'                     => array( 'jquery-color' ),
diff --git a/tools/vendors/espree-entry.js b/tools/vendors/espree-entry.js
@@ -0,0 +1,2 @@
+/* jshint node:true */
+window.espree = require( 'espree' );
diff --git a/tools/webpack/codemirror.config.js b/tools/webpack/codemirror.config.js
@@ -11,10 +11,13 @@ module.exports = ( env = { buildTarget: 'src/' } ) => {
 	return {
 		target: 'browserslist',
 		mode: 'production',
-		entry: './tools/vendors/codemirror-entry.js',
+		entry: {
+			'codemirror.min': './tools/vendors/codemirror-entry.js',
+			'espree.min': './tools/vendors/espree-entry.js',
+		},
 		output: {
 			path: path.resolve( __dirname, '../../', buildTarget, 'wp-includes/js/codemirror' ),
-			filename: 'codemirror.min.js',
+			filename: '[name].js',
 		},
 		optimization: {
 			minimize: true,

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+/* jshint node:true */`
	`2`	`+window.espree = require( 'espree' );`