fix($core): remove smoothing scroll (close: #1071) (#1075)

packages/@vuepress/core/lib/app/app.js

@@ -62,7 +62,15 @@ export function createApp (isServer) {
     base: siteData.base,
     mode: 'history',
     fallback: false,
-    routes
+    routes,
+    scrollBehavior (to, from, savedPosition) {
+      if (savedPosition) {
+        return savedPosition
+      }
+      if (to.path !== from.path) {
+        return { x: 0, y: 0 }
+      }
+    }
   })
 
   // redirect /foo to /foo/

packages/@vuepress/core/lib/app/root-mixins/updateLoadingState.js

-import SmoothScroll from 'smooth-scroll/dist/smooth-scroll.js'
-
 export default {
   created () {
     this.$vuepress.$on('AsyncMarkdownContentMounted', () => {
       this.$vuepress.$set('contentMounted', true)
-
-      this.$smoothScroll = new SmoothScroll('a[href*="#"]', {
-        speed: 1,
-        speedAsDuration: true,
-        easing: 'easeInOutCubic'
-      })
-
-      if (this.$route.hash) {
-        const hash = decodeURIComponent(this.$route.hash)
-        try {
-          const anchor = document.getElementById(hash.slice(1))
-          const anchorLink = anchor.querySelector('a.header-anchor')
-          setTimeout(() => {
-            window.scroll({
-              top: anchorLink.offsetTop - 70,
-              left: 0,
-              behavior: 'auto'
-            })
-          })
-        } catch (e) {
-          console.error(e)
-        }
-      }
     })
   },
 
   watch: {
     '$route.path' () {
       this.$vuepress.$set('contentMounted', false)
-      this.$smoothScroll.destroy()
     }
-  },
-
-  beforeDestroy () {
-    this.$smoothScroll.destroy()
   }
 }

packages/@vuepress/core/package.json

@@ -55,7 +55,6 @@
     "optimize-css-assets-webpack-plugin": "^4.0.0",
     "portfinder": "^1.0.13",
     "postcss-loader": "^2.1.5",
-    "smooth-scroll": "^15.0.0",
     "toml": "^2.3.3",
     "url-loader": "^1.0.1",
     "vue": "^2.5.16",

yarn.lock

@@ -7606,10 +7606,6 @@ slice-ansi@1.0.0:
   dependencies:
     is-fullwidth-code-point "^2.0.0"
 
-smooth-scroll@^15.0.0:
-  version "15.0.0"
-  resolved "https://registry.yarnpkg.com/smooth-scroll/-/smooth-scroll-15.0.0.tgz#be4f9cb2cc4952d80db6736e5656ed5849305272"
-
 snapdragon-node@^2.0.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/snapdragon-node/-/snapdragon-node-2.1.1.tgz#6c175f86ff14bdb0724563e8f3c1b021a286853b"