From 0929ff03ced70be879ac3e2a8f66618199bea4ee Mon Sep 17 00:00:00 2001
From: Jon Koops <jonkoops@gmail.com>
Date: Tue, 5 Jul 2022 13:01:23 +0200
Subject: [PATCH] Add utilty function to check for defined values (#2923)

---
 src/utils/isDefined.test.ts     | 14 ++++++++++++++
 src/utils/isDefined.ts          |  3 +++
 src/utils/useRequiredContext.ts |  7 ++++---
 3 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 src/utils/isDefined.test.ts
 create mode 100644 src/utils/isDefined.ts

diff --git a/src/utils/isDefined.test.ts b/src/utils/isDefined.test.ts
new file mode 100644
index 0000000000..5c4af1f830
--- /dev/null
+++ b/src/utils/isDefined.test.ts
@@ -0,0 +1,14 @@
+import { isDefined } from "./isDefined";
+
+describe("isDefined", () => {
+  it("detects defined values", () => {
+    expect(isDefined(0)).toBe(true);
+    expect(isDefined(false)).toBe(true);
+    expect(isDefined("")).toBe(true);
+  });
+
+  it("detects undefined values", () => {
+    expect(isDefined(undefined)).toBe(false);
+    expect(isDefined(null)).toBe(false);
+  });
+});
diff --git a/src/utils/isDefined.ts b/src/utils/isDefined.ts
new file mode 100644
index 0000000000..ef5e00ab26
--- /dev/null
+++ b/src/utils/isDefined.ts
@@ -0,0 +1,3 @@
+export function isDefined<T>(value: T): value is NonNullable<T> {
+  return value !== undefined && value !== null;
+}
diff --git a/src/utils/useRequiredContext.ts b/src/utils/useRequiredContext.ts
index 63adb9d3b5..aa6e6b9649 100644
--- a/src/utils/useRequiredContext.ts
+++ b/src/utils/useRequiredContext.ts
@@ -1,5 +1,6 @@
-import { useContext } from "react";
 import type { Context } from "react";
+import { useContext } from "react";
+import { isDefined } from "./isDefined";
 
 /**
  * Passes the call to `useContext` and throw an exception if the resolved value is either `null` or `undefined`.
@@ -13,8 +14,8 @@ export default function useRequiredContext<T>(
 ): NonNullable<T> {
   const resolved = useContext(context);
 
-  if (resolved !== undefined && resolved !== null) {
-    return resolved as NonNullable<T>;
+  if (isDefined(resolved)) {
+    return resolved;
   }
 
   throw new Error(