From: Evan You <yyx990803@gmail.com>
Date: Tue, 5 Nov 2019 15:49:00 +0000 (-0500)
Subject: feat: warn duplicate plugin installations
X-Git-Tag: v3.0.0-alpha.0~237
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c61e5463fa77a56c4271db958e4a8e48bb2ae233;p=thirdparty%2Fvuejs%2Fcore.git

feat: warn duplicate plugin installations
---

diff --git a/packages/runtime-core/__tests__/apiApp.spec.ts b/packages/runtime-core/__tests__/apiApp.spec.ts
index c78d9157e9..417cb77245 100644
--- a/packages/runtime-core/__tests__/apiApp.spec.ts
+++ b/packages/runtime-core/__tests__/apiApp.spec.ts
@@ -259,6 +259,11 @@ describe('api: createApp', () => {
     const root = nodeOps.createElement('div')
     app.mount(Root, root)
     expect(serializeInner(root)).toBe(`1,2`)
+
+    app.use(PluginA)
+    expect(
+      `Plugin has already been applied to target app`
+    ).toHaveBeenWarnedTimes(1)
   })
 
   test('config.errorHandler', () => {
diff --git a/packages/runtime-core/src/apiApp.ts b/packages/runtime-core/src/apiApp.ts
index e431945c78..7b757240ea 100644
--- a/packages/runtime-core/src/apiApp.ts
+++ b/packages/runtime-core/src/apiApp.ts
@@ -79,6 +79,7 @@ export function createAppAPI<HostNode, HostElement>(
 ): () => App<HostElement> {
   return function createApp(): App {
     const context = createAppContext()
+    const installedPlugins = new Set()
 
     let isMounted = false
 
@@ -96,9 +97,13 @@ export function createAppAPI<HostNode, HostElement>(
       },
 
       use(plugin: Plugin) {
-        if (isFunction(plugin)) {
+        if (installedPlugins.has(plugin)) {
+          __DEV__ && warn(`Plugin has already been applied to target app.`)
+        } else if (isFunction(plugin)) {
+          installedPlugins.add(plugin)
           plugin(app)
         } else if (isFunction(plugin.install)) {
+          installedPlugins.add(plugin)
           plugin.install(app)
         } else if (__DEV__) {
           warn(