refactor(core): adjust directory structure:

src/core/init/index.js

@@ -0,0 +1,27 @@
+import config from '../config'
+import { initLifecycle, callHook } from './lifecycle'
+import { initRender } from '../render'
+import { initRoute } from '../route'
+import { initEvent } from '../event'
+import { initFetch } from '../fetch'
+import { isFn } from '../util/core'
+
+export function initMixin (Docsify) {
+  Docsify.prototype._init = function () {
+    const vm = this
+    vm._config = config || {}
+
+    initLifecycle(vm) // Init hooks
+    initPlugin(vm) // Install plugins
+    callHook(vm, 'init')
+    initRender(vm) // Render base DOM
+    initEvent(vm) // Bind events
+    initRoute(vm) // Add hashchange eventListener
+    initFetch(vm) // Fetch data
+    callHook(vm, 'ready')
+  }
+}
+
+function initPlugin (vm) {
+  [].concat(vm.config.plugins).forEach(fn => isFn(fn) && fn(vm.bindHook))
+}

src/core/init/lifecycle.js

@@ -0,0 +1,41 @@
+import { noop } from '../util/core'
+
+export function initLifecycle (vm) {
+  const hooks = ['init', 'beforeEach', 'afterEach', 'doneEach', 'ready']
+
+  vm._hooks = {}
+  vm.bindHook = {}
+  hooks.forEach(hook => {
+    const arr = vm._hooks[hook] = []
+    vm._bindHook[hook] = fn => arr.push(fn)
+  })
+}
+
+export function callHook (vm, hook, data, next = noop) {
+  let newData = data
+  const queue = vm._hooks[hook]
+
+  const step = function (index) {
+    const hook = queue[index]
+    if (index >= queue.length) {
+      next(newData)
+    } else {
+      if (typeof hook === 'function') {
+        if (hook.length === 2) {
+          hook(data, result => {
+            newData = result
+            step(index + 1)
+          })
+        } else {
+          const result = hook(data)
+          newData = result !== undefined ? result : newData
+          step(index + 1)
+        }
+      } else {
+        step(index + 1)
+      }
+    }
+  }
+
+  step(0)
+}