feat: add options validator

src/helpers/index.js

@@ -1,7 +1,9 @@
 const createRefreshTemplate = require('./createRefreshTemplate');
 const injectRefreshEntry = require('./injectRefreshEntry');
+const validateOptions = require('./validateOptions');
 
 module.exports = {
   createRefreshTemplate,
   injectRefreshEntry,
+  validateOptions,
 };

src/helpers/validateOptions.js

@@ -0,0 +1,41 @@
+/** @type {import('../types').ReactRefreshPluginOptions} */
+const defaultOptions = {
+  disableRefreshCheck: false,
+  forceEnable: false,
+  useLegacyWDSSockets: false,
+};
+
+/** @type {import('../types').ErrorOverlayOptions} */
+const defaultOverlayOptions = {
+  entry: require.resolve('../runtime/ErrorOverlayEntry'),
+  overlay: require.resolve('../overlay'),
+};
+
+/**
+ * Validates the options for the plugin.
+ * @param {import('../types').ReactRefreshPluginOptions} options Non-validated plugin options object.
+ * @returns {import('../types').ReactRefreshPluginOptions} Validated plugin options.
+ */
+module.exports = function validateOptions(options) {
+  const validatedOptions = Object.assign(defaultOptions, options);
+
+  if (typeof validatedOptions.overlay !== 'boolean') {
+    if (typeof validatedOptions.overlay.module !== 'string') {
+      throw new Error(
+        `To use the "overlay" option, a string must be provided in the "module" property. Instead, the provided value has type: "${typeof options
+          .overlay.module}".`
+      );
+    }
+
+    validatedOptions.overlay = {
+      entry: options.overlay.entry || defaultOverlayOptions.entry,
+      module: options.overlay.module,
+    };
+  } else {
+    validatedOptions.overlay =
+      (typeof validatedOptions.overlay === 'undefined' || validatedOptions.overlay) &&
+      defaultOverlayOptions;
+  }
+
+  return validatedOptions;
+};

src/index.js

@@ -9,7 +9,7 @@ class ReactRefreshPlugin {
    * @returns {void}
    */
   constructor(options) {
-    this.options = Object.assign(defaultOptions, options);
+    this.options = validateOptions(options);
   }
 
   /**