diff --git a/lib/index.js b/lib/index.js
index 625ee6e..0761e0f 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -8,16 +8,30 @@
* @typedef {HastParent['children'][number]} HastChild
* @typedef {HastChild|HastRoot} HastNode
*
+ * @callback AfterTransform
+ * Function called when a hast node is transformed into a DOM node
+ * @param {HastNode} hastNode
+ * The hast node that was handled
+ * @param {Node} domNode
+ * The corresponding DOM node
+ * @returns {void}
+ *
* @typedef Options
- * @property {boolean} [fragment=false] Whether a DOM fragment should be returned
- * @property {Document} [document] Document interface to use (default: `globalThis.document`)
- * @property {string} [namespace] `namespace` to use to create elements
+ * @property {boolean} [fragment=false]
+ * Whether a DOM fragment should be returned
+ * @property {Document} [document]
+ * Document interface to use (default: `globalThis.document`)
+ * @property {string} [namespace]
+ * `namespace` to use to create elements
+ * @property {AfterTransform} [afterTransform]
+ * Callback invoked after each node transformation
*
* @typedef Context
* @property {Document} doc
* @property {boolean} [fragment=false]
* @property {string} [namespace]
* @property {string} [impliedNamespace]
+ * @property {AfterTransform} [afterTransform]
*/
import {webNamespaces} from 'web-namespaces'
@@ -30,6 +44,16 @@ import {find, html, svg} from 'property-information'
* @param {Context} ctx
*/
function transform(node, ctx) {
+ const transformed = one(node, ctx)
+ if (ctx.afterTransform) ctx.afterTransform(node, transformed)
+ return transformed
+}
+
+/**
+ * @param {HastNode} node
+ * @param {Context} ctx
+ */
+function one(node, ctx) {
switch (node.type) {
case 'root':
return root(node, ctx)
diff --git a/readme.md b/readme.md
index ba487b4..eb05134 100644
--- a/readme.md
+++ b/readme.md
@@ -88,6 +88,12 @@ Document interface to use (default: `globalThis.document`).
`namespace` to use to create [*elements*][element].
+###### `options.afterTransform`
+
+Function called when a hast node is transformed into a DOM node (`Function?`).
+Given the hast node that was handled as the first parameter and the
+corresponding DOM node as the second parameter.
+
## Security
Use of `hast-util-to-dom` can open you up to a
diff --git a/test/index.js b/test/index.js
index cb00e96..23adafc 100644
--- a/test/index.js
+++ b/test/index.js
@@ -359,6 +359,25 @@ test('hast-util-to-dom', (t) => {
'encodes data properties when string'
)
+ t.deepEqual(
+ (() => {
+ /** @type {Array<[HastNode, string]>} */
+ const calls = []
+ toDom(h('html', [h('title', 'Hi')]), {
+ afterTransform: (node, transformed) => {
+ calls.push([node, serializeNodeToHtmlString(transformed)])
+ }
+ })
+ return calls
+ })(),
+ [
+ [{type: 'text', value: 'Hi'}, 'Hi'],
+ [h('title', 'Hi'), 'Hi'],
+ [h('html', [h('title', 'Hi')]), 'Hi']
+ ],
+ 'should invoke afterTransform'
+ )
+
t.end()
})