1 files changed, 142 insertions, 0 deletions
diff --git a/node_modules/vue/src/core/instance/events.js b/node_modules/vue/src/core/instance/events.js
new file mode 100644
index 00000000..58779996
--- /dev/null
+++ b/node_modules/vue/src/core/instance/events.js
@@ -0,0 +1,142 @@
+/* @flow */
+
+import {
+  tip,
+  toArray,
+  hyphenate,
+  handleError,
+  formatComponentName
+} from '../util/index'
+import { updateListeners } from '../vdom/helpers/index'
+
+export function initEvents (vm: Component) {
+  vm._events = Object.create(null)
+  vm._hasHookEvent = false
+  // init parent attached events
+  const listeners = vm.$options._parentListeners
+  if (listeners) {
+    updateComponentListeners(vm, listeners)
+  }
+}
+
+let target: any
+
+function add (event, fn, once) {
+  if (once) {
+    target.$once(event, fn)
+  } else {
+    target.$on(event, fn)
+  }
+}
+
+function remove (event, fn) {
+  target.$off(event, fn)
+}
+
+export function updateComponentListeners (
+  vm: Component,
+  listeners: Object,
+  oldListeners: ?Object
+) {
+  target = vm
+  updateListeners(listeners, oldListeners || {}, add, remove, vm)
+  target = undefined
+}
+
+export function eventsMixin (Vue: Class<Component>) {
+  const hookRE = /^hook:/
+  Vue.prototype.$on = function (event: string | Array<string>, fn: Function): Component {
+    const vm: Component = this
+    if (Array.isArray(event)) {
+      for (let i = 0, l = event.length; i < l; i++) {
+        this.$on(event[i], fn)
+      }
+    } else {
+      (vm._events[event] || (vm._events[event] = [])).push(fn)
+      // optimize hook:event cost by using a boolean flag marked at registration
+      // instead of a hash lookup
+      if (hookRE.test(event)) {
+        vm._hasHookEvent = true
+      }
+    }
+    return vm
+  }
+
+  Vue.prototype.$once = function (event: string, fn: Function): Component {
+    const vm: Component = this
+    function on () {
+      vm.$off(event, on)
+      fn.apply(vm, arguments)
+    }
+    on.fn = fn
+    vm.$on(event, on)
+    return vm
+  }
+
+  Vue.prototype.$off = function (event?: string | Array<string>, fn?: Function): Component {
+    const vm: Component = this
+    // all
+    if (!arguments.length) {
+      vm._events = Object.create(null)
+      return vm
+    }
+    // array of events
+    if (Array.isArray(event)) {
+      for (let i = 0, l = event.length; i < l; i++) {
+        this.$off(event[i], fn)
+      }
+      return vm
+    }
+    // specific event
+    const cbs = vm._events[event]
+    if (!cbs) {
+      return vm
+    }
+    if (!fn) {
+      vm._events[event] = null
+      return vm
+    }
+    if (fn) {
+      // specific handler
+      let cb
+      let i = cbs.length
+      while (i--) {
+        cb = cbs[i]
+        if (cb === fn || cb.fn === fn) {
+          cbs.splice(i, 1)
+          break
+        }
+      }
+    }
+    return vm
+  }
+
+  Vue.prototype.$emit = function (event: string): Component {
+    const vm: Component = this
+    if (process.env.NODE_ENV !== 'production') {
+      const lowerCaseEvent = event.toLowerCase()
+      if (lowerCaseEvent !== event && vm._events[lowerCaseEvent]) {
+        tip(
+          `Event "${lowerCaseEvent}" is emitted in component ` +
+          `${formatComponentName(vm)} but the handler is registered for "${event}". ` +
+          `Note that HTML attributes are case-insensitive and you cannot use ` +
+          `v-on to listen to camelCase events when using in-DOM templates. ` +
+          `You should probably use "${hyphenate(event)}" instead of "${event}".`
+        )
+      }
+    }
+    let cbs = vm._events[event]
+    if (cbs) {
+      cbs = cbs.length > 1 ? toArray(cbs) : cbs
+      const args = toArray(arguments, 1)
+      for (let i = 0, l = cbs.length; i < l; i++) {
+        try {
+          cbs[i].apply(vm, args)
+        } catch (e) {
+          handleError(e, vm, `event handler for "${event}"`)
+        }
+      }
+    }
+    return vm
+  }
+}