Added ability for mdxJSX elements to not be stripped out, and also added the ability for attributes whitelisted on those elements to not be stripped

Author: cobbvanth

lib/index.js

@@ -288,6 +288,62 @@ function transform(state, node) {
         return text(state, unsafe)
       }
 
+      case 'mdxJsxFlowElement': {
+        // Map the attributes array into name/value pairs
+        const attributesMap = {}
+        if (Array.isArray(unsafe.attributes)) {
+          unsafe.attributes.forEach((attr) => {
+            if (
+              attr &&
+              typeof attr === 'object' &&
+              'name' in attr &&
+              'value' in attr
+            ) {
+              attributesMap[attr.name] = attr.value
+            }
+          })
+        }
+
+        const mdxProps = {
+          ...unsafe,
+          tagName: unsafe.name,
+          properties: {
+            ...unsafe.properties,
+            ...attributesMap // Spread the mapped attributes directly into properties
+          }
+        }
+
+        return element(state, mdxProps)
+      }
+
+      case 'mdxJsxTextElement': {
+        // Handle text elements the same way
+        const attributesMap = {}
+        if (Array.isArray(unsafe.attributes)) {
+          unsafe.attributes.forEach((attr) => {
+            if (
+              attr &&
+              typeof attr === 'object' &&
+              'name' in attr &&
+              'value' in attr
+            ) {
+              attributesMap[attr.name] = attr.value
+            }
+          })
+        }
+
+        const mdxProps = {
+          ...unsafe,
+          tagName: unsafe.name,
+          properties: {
+            ...unsafe.properties,
+            ...attributesMap
+          }
+        }
+
+        return element(state, mdxProps)
+      }
+
       default:
     }
   }
@@ -503,15 +559,18 @@ function properties(state, properties) {
       : undefined
   const defaults =
     attributes && own.call(attributes, '*') ? attributes['*'] : undefined
+
+  // Handle both traditional properties and MDX attributes
   const properties_ =
-    /** @type {Readonly<Record<string, Readonly<unknown>>>} */ (
-      properties && typeof properties === 'object' ? properties : {}
-    )
+    properties && typeof properties === 'object' ? properties : {}
+  const mdxAttributes = properties_?.attributes || {} // Add support for MDX attributes
+
   /** @type {Properties} */
   const result = {}
   /** @type {string} */
   let key
 
+  // Process traditional properties
   for (key in properties_) {
     if (own.call(properties_, key)) {
       const unsafe = properties_[key]
@@ -532,9 +591,30 @@ function properties(state, properties) {
     }
   }
 
+  // Process MDX attributes
+  for (key in mdxAttributes) {
+    if (own.call(mdxAttributes, key)) {
+      const unsafe = mdxAttributes[key]
+      let safe = propertyValue(
+        state,
+        findDefinition(specific, key),
+        key,
+        unsafe
+      )
+
+      if (safe === null || safe === undefined) {
+        safe = propertyValue(state, findDefinition(defaults, key), key, unsafe)
+      }
+
+      if (safe !== null && safe !== undefined) {
+        result[key] = safe
+      }
+    }
+  }
+
+  // Handle required properties
   if (required && own.call(required, tagName)) {
     const properties = required[tagName]
-
     for (key in properties) {
       if (own.call(properties, key) && !own.call(result, key)) {
         result[key] = properties[key]