TypeScript: Migrate is-shallow-equal package to TypeScript (#70407)

* refactor: migrate is-shallow-equal package from js to ts for type safety

* docs: remove jsDoc types as used ts

Author: kushagra-goyal-14

packages/is-shallow-equal/src/arrays.js renamed to packages/is-shallow-equal/src/arrays.ts

@@ -1,12 +1,15 @@
 /**
  * Returns true if the two arrays are shallow equal, or false otherwise.
  *
- * @param {any[]} a First array to compare.
- * @param {any[]} b Second array to compare.
+ * @param a First array to compare.
+ * @param b Second array to compare.
  *
- * @return {boolean} Whether the two arrays are shallow equal.
+ * @return Whether the two arrays are shallow equal.
  */
-export default function isShallowEqualArrays( a, b ) {
+export default function isShallowEqualArrays(
+	a: unknown[],
+	b: unknown[]
+): boolean {
 	if ( a === b ) {
 		return true;
 	}

packages/is-shallow-equal/src/index.js renamed to packages/is-shallow-equal/src/index.ts

@@ -7,20 +7,18 @@ import isShallowEqualArrays from './arrays';
 export { default as isShallowEqualObjects } from './objects';
 export { default as isShallowEqualArrays } from './arrays';
 
-/**
- * @typedef {Record<string, any>} ComparableObject
- */
+export type ComparableObject = Record< string, any >;
 
 /**
  * Returns true if the two arrays or objects are shallow equal, or false
  * otherwise. Also handles primitive values, just in case.
  *
- * @param {unknown} a First object or array to compare.
- * @param {unknown} b Second object or array to compare.
+ * @param a First object or array to compare.
+ * @param b Second object or array to compare.
  *
- * @return {boolean} Whether the two values are shallow equal.
+ * @return Whether the two values are shallow equal.
  */
-export default function isShallowEqual( a, b ) {
+export default function isShallowEqual( a: unknown, b: unknown ): boolean {
 	if ( a && b ) {
 		if ( a.constructor === Object && b.constructor === Object ) {
 			return isShallowEqualObjects( a, b );

packages/is-shallow-equal/src/objects.js renamed to packages/is-shallow-equal/src/objects.ts

@@ -1,12 +1,20 @@
+/**
+ * Internal dependencies
+ */
+import type { ComparableObject } from '.';
+
 /**
  * Returns true if the two objects are shallow equal, or false otherwise.
  *
- * @param {import('.').ComparableObject} a First object to compare.
- * @param {import('.').ComparableObject} b Second object to compare.
+ * @param a First object to compare.
+ * @param b Second object to compare.
  *
- * @return {boolean} Whether the two objects are shallow equal.
+ * @return Whether the two objects are shallow equal.
  */
-export default function isShallowEqualObjects( a, b ) {
+export default function isShallowEqualObjects(
+	a: ComparableObject,
+	b: ComparableObject
+): boolean {
 	if ( a === b ) {
 		return true;
 	}