fix: Linting issues and use inBrowser check for requestIdleCallback

Author: prashantpalikhe

src/index.js

@@ -1,5 +1,5 @@
 import prefetch from './prefetch'
-import { canPrefetch, supportIntersectionObserver } from './utils'
+import { canPrefetch, supportIntersectionObserver, inBrowser } from './utils'
 
 function installRouterPrefetch(Vue, { componentName = 'RouterLink' } = {}) {
   const observer =
@@ -12,17 +12,18 @@ function installRouterPrefetch(Vue, { componentName = 'RouterLink' } = {}) {
       })
     })
 
-    const requestIdleCallback = window.requestIdleCallback ||
-      function (cb) {
-        const start = Date.now()
-        return setTimeout(function () {
-          cb({
-            didTimeout: false,
-            timeRemaining: function () {
-              return Math.max(0, 50 - (Date.now() - start))
-            },
-          })
-        }, 1)
+  const requestIdleCallback =
+    (inBrowser && window.requestIdleCallback) ||
+    function(cb) {
+      const start = Date.now()
+      return setTimeout(() => {
+        cb({
+          didTimeout: false,
+          timeRemaining() {
+            return Math.max(0, 50 - (Date.now() - start))
+          }
+        })
+      }, 1)
     }
 
   const RouterLink = Vue.component('RouterLink') || Vue.component('router-link')
@@ -47,7 +48,7 @@ function installRouterPrefetch(Vue, { componentName = 'RouterLink' } = {}) {
     },
     mounted() {
       if (this.prefetch && observer && canPrefetch) {
-        requestIdleCallback(this.observe, { timeout: 1000 });
+        requestIdleCallback(this.observe, { timeout: 1000 })
       }
     },
     beforeDestory() {