Replace setImmediate with queueMicrotask.

lib/index.js

@@ -1,7 +1,5 @@
 "use strict";
 
-require(`setimmediate`);
-
 // An order represents a pending push or shift.
 const Order = (channel) => {
   let order;
@@ -249,7 +247,7 @@ const Channel = function(length = 0) {
       shift: function() {
         const { order, promise } = Order(this);
         shifts.push(order);
-        setImmediate(processOrders);
+        queueMicrotask(processOrders);
 
         // Don't freeze promise because Bluebird expects it to be mutable.
         return promise;
@@ -321,7 +319,7 @@ const Channel = function(length = 0) {
             processOrders();
 
             // Give remaining orders in flight time to resolve before returning.
-            setImmediate(resolve);
+            queueMicrotask(resolve);
           }
         }),
 
@@ -348,7 +346,7 @@ const Channel = function(length = 0) {
           order.reject(new Error(`Can't push more than one value at a time.`));
         } else {
           pushes.push(order);
-          setImmediate(processOrders);
+          queueMicrotask(processOrders);
         }
 
         // Don't freeze promise because Bluebird expects it to be mutable.

package-lock.json

@@ -2344,11 +2344,6 @@
       "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==",
       "dev": true
     },
-    "setimmediate": {
-      "version": "1.0.5",
-      "resolved": "https://registry.npmjs.org/setimmediate/-/setimmediate-1.0.5.tgz",
-      "integrity": "sha1-KQy7Iy4waULX1+qbg3Mqt4VvgoU="
-    },
     "shebang-command": {
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/shebang-command/-/shebang-command-1.2.0.tgz",

package.json

@@ -10,9 +10,7 @@
   "bugs": {
     "url": "https://gitlab.com/NodeGuy/channel/issues"
   },
-  "dependencies": {
-    "setimmediate": "1.0.5"
-  },
+  "dependencies": {},
   "devDependencies": {
     "@nodeguy/assert": "0.1.4",
     "@stryker-mutator/core": "1.1.0",