Merge pull request #5 from abcnews/bug/types

bug: BlockMount is a div

Author: AshKyd

src/index.ts

@@ -2,8 +2,7 @@ type MountValue = string;
 type MountValuePrefix = string;
 type MountSelector = string;
 type MountSelectorTemplate = string[];
-type BlockMount = Element & {
-  tagName: 'DIV';
+type BlockMount = HTMLDivElement & {
   id: MountValue;
   dataset: {
     mount: string;
@@ -67,8 +66,8 @@ function isNode(x: unknown): x is Node {
   return typeof x === 'object' && x instanceof Node;
 }
 
-function isElement(x: unknown): x is Element {
-  return isNode(x) && x.nodeType === Node.ELEMENT_NODE;
+function isDiv(x: unknown): x is HTMLDivElement {
+  return isNode(x) && x instanceof HTMLElement && x.tagName === 'DIV';
 }
 
 export function isMount(
@@ -77,12 +76,12 @@ export function isMount(
   exact: boolean = false
 ): x is Mount {
   return (
-    isElement(x) &&
+    isDiv(x) &&
     (value === undefined
       ? x.matches(MOUNT_SELECTOR)
       : exact
-      ? x.matches(exactMountSelector(value))
-      : x.matches(prefixedMountSelector(value)))
+        ? x.matches(exactMountSelector(value))
+        : x.matches(prefixedMountSelector(value)))
   );
 }