Add Check If An Object Is Empty With Zod as a JavaScript TIL

javascript/check-if-an-object-is-empty-with-zod.md

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+# Check If An Object Is Empty With Zod
+
+Zod is a schema validation library. It can be used to check all sorts of
+properties about the data moving through our system.
+
+Let's look at how to implement a common type of check -- is this object empty?
+
+```javascript
+import {z} from 'zod';
+
+const emptyObjectSchema = z.object({}).strict();
+const isEmpty = (obj: object): boolean => {
+  const result = emptyObjectSchema.safeParse(obj);
+  return result.success;
+}
+
+isEmpty({});
+//=> true
+
+isEmpty({ hello: 'world' });
+//=> false
+```
+
+This `emptyObjectSchema` _strictly_ defines the schema as an empty object
+(`{}`). Without the [`strict()`](https://github.com/colinhacks/zod#strict)
+part, we'd be allowing an object with key-value pairs to quietly pass the
+validation.
+
+[source](https://twitter.com/jbrancha/status/1565728882082385920)