1 files changed, 47 insertions, 0 deletions
diff --git a/src/frontend/render/utils.ts b/src/frontend/render/utils.ts
new file mode 100644
index 000000000..7001a7f95
--- /dev/null
+++ b/src/frontend/render/utils.ts
@@ -0,0 +1,47 @@
+import unified from 'unified';
+import parse from 'rehype-parse';
+import toH from 'hast-to-hyperscript';
+import { ComponentRenderer } from '../../@types/renderer';
+import moize from 'moize';
+
+/** @internal */
+function childrenToTree(children: string[]) {
+    return children.map(child => (unified().use(parse, { fragment: true }).parse(child) as any).children.pop());
+}
+
+/**
+ * Converts an HTML fragment string into vnodes for rendering via provided framework
+ * @param h framework's `createElement` function
+ * @param children the HTML string children
+ */
+export const childrenToVnodes = moize.deep(function childrenToVnodes(h: any, children: string[]) {
+    const tree = childrenToTree(children);
+    const vnodes = tree.map(subtree => toH(h, subtree));
+    return vnodes;
+})
+
+/**
+ * Converts an HTML fragment string into h function calls as a string
+ * @param h framework's `createElement` function
+ * @param children the HTML string children
+ */
+export const childrenToH = moize.deep(function childrenToH(renderer: ComponentRenderer<any>, children: string[]): any {
+    if (!renderer.jsxPragma) return;
+    const tree = childrenToTree(children);
+    const innerH = (name: any, attrs: Record<string, any>|null = null, _children: string[]|null = null) => {
+        const vnode = renderer.jsxPragma?.(name, attrs, _children);
+        const childStr = _children ? `, [${_children.map(child => serializeChild(child)).join(',')}]` : '';
+        /* fix(react): avoid hard-coding keys into the serialized tree */
+        if (attrs && attrs.key) attrs.key = undefined;
+        const __SERIALIZED = `${renderer.jsxPragmaName}("${name}", ${attrs ? JSON.stringify(attrs) : 'null'}${childStr})` as string;
+        return { ...vnode, __SERIALIZED }
+    }
+    const serializeChild = (child: unknown) => {
+        if (typeof child === 'string') return `\`${child}\``;
+        if (typeof child === 'number' || typeof child === 'boolean') return `${child}`;
+        if (child === null) return `null`;
+        if ((child as any).__SERIALIZED) return (child as any).__SERIALIZED;
+        return innerH(child).__SERIALIZED;
+    }
+    return tree.map(subtree => toH(innerH, subtree).__SERIALIZED);
+})