tagHandler - Add tagHandler, handles only h1 now

src/tagHandler.ts

@@ -0,0 +1,30 @@
+import { heading } from 'mdast-builder';
+// tslint:disable-next-line: no-implicit-dependencies
+import { Node as MDASTNode, Parent as MDASTParent } from 'unist';
+import { IReactElementSubset } from './helpers';
+
+export default function handleTag(
+  node: IReactElementSubset,
+  parentASTNode: MDASTParent
+) {
+  const { type: tagType } = node;
+
+  let childASTNode: MDASTNode | undefined;
+  let newParentASTNode: MDASTParent | undefined;
+
+  switch (tagType) {
+    case 'h1':
+      newParentASTNode = childASTNode = heading(1);
+      break;
+
+    default:
+      newParentASTNode = parentASTNode;
+      break;
+  }
+
+  if (childASTNode !== undefined) {
+    parentASTNode.children.push(childASTNode);
+  }
+
+  return newParentASTNode;
+}