add deno checker

Author: behnammodi

readme.md

@@ -11,7 +11,7 @@ if (isBrowser) {
 More thoroughly:
 
 ```js
-import { isJsDom, isNode, isBrowser } from "is-in-browser";
+import { isJsDom, isNode, isBrowser, isDeno } from "is-in-browser";
 
 if (isBrowser) {
   // you're in the browser
@@ -25,6 +25,10 @@ if (isJsDom) {
 if (isNode) {
   // you're in the Node
 }
+
+if (isDeno) {
+  // you're in the Deno
+}
 ```
 
 ## CommonJS

src/index.ts

@@ -11,4 +11,8 @@ export const isBrowser =
   typeof document === "object" &&
   document.nodeType === 9;
 
+export const isDeno =
+  typeof window === "object" &&
+  typeof window.Deno === "object"
+
 export default isBrowser;

src/node.check.ts

@@ -1,8 +1,10 @@
-import { isBrowser, isNode, isJsDom } from "./index";
+import { isBrowser, isNode, isJsDom, isDeno } from "./index";
 
 console.log(isBrowser ? "❌" : "✅", "browser:", isBrowser);
 console.log(isNode ? "✅" : "❌", "node:", isNode);
 console.log(isBrowser ? "❌" : "✅", "js-dom:", isJsDom);
+console.log(isDeno ? "❌" : "✅", "deno:", isDeno);
+
 
 if (isBrowser || !isNode || isJsDom) {
   process.exit(1);

src/test.ts

@@ -1,4 +1,4 @@
-import isInBrowser, { isBrowser, isJsDom, isNode } from ".";
+import isInBrowser, { isBrowser, isDeno, isJsDom, isNode } from ".";
 
 test("isInBrowser", () => {
   // jest runs jsdom, so true
@@ -13,5 +13,8 @@ test("isInBrowser", () => {
   // jest runs on Node, so true
   expect(isNode).toBe(true);
 
+  // jest runs on Deno, so true
+  expect(isDeno).toBe(true);
+
   // jest runs JSDOm, so true
 });