fix: skip loading plugin if already loaded

src/config.ts

@@ -90,25 +90,26 @@ export interface IConfig extends Plugin.IPlugin {
 }
 
 export class Config extends Plugin.Plugin implements IConfig {
-  arch: ArchTypes
-  bin: string
-  cacheDir: string
-  configDir: string
-  dataDir: string
-  dirname: string
-  errlog: string
-  home: string
-  platform: PlatformTypes
-  shell: string
-  windows: boolean
-  userAgent: string
+  arch!: ArchTypes
+  bin!: string
+  cacheDir!: string
+  configDir!: string
+  dataDir!: string
+  dirname!: string
+  errlog!: string
+  home!: string
+  platform!: PlatformTypes
+  shell!: string
+  windows!: boolean
+  userAgent!: string
   debug: number = 0
-  npmRegistry: string
+  npmRegistry!: string
   pjson!: PJSON.CLI
   userPJSON?: PJSON.User
 
   constructor(opts: Plugin.Options) {
     super(opts)
+    if (this.alreadyLoaded) return
 
     this.arch = (os.arch() === 'ia32' ? 'x86' : os.arch() as any)
     this.platform = os.platform() as any

src/plugin.ts

@@ -94,14 +94,18 @@ export class Plugin implements IPlugin {
   hooks!: {[k: string]: string[]}
   valid!: boolean
   ignoreManifest: boolean
+  alreadyLoaded = false
 
   constructor(opts: Options) {
     this.ignoreManifest = !!opts.ignoreManifest
     this.type = opts.type || 'core'
     this.tag = opts.tag
     const root = findRoot(opts.name, opts.root)
     if (!root) throw new Error(`could not find package.json with ${inspect(opts)}`)
-    if (Plugin.loadedPlugins[root]) return Plugin.loadedPlugins[root]
+    if (Plugin.loadedPlugins[root]) {
+      this.alreadyLoaded = true
+      return Plugin.loadedPlugins[root]
+    }
     Plugin.loadedPlugins[root] = this
     this.root = root
     debug('reading plugin %s', root)