From 3ae7e7044d06daa2ea76e24af15358c5764b9887 Mon Sep 17 00:00:00 2001
From: Shigma <1700011071@pku.edu.cn>
Date: Mon, 20 Jan 2020 16:10:07 +0800
Subject: [PATCH] fix(core): create major context at demand

---
 packages/koishi-core/src/app.ts     | 35 ++++++++++++++++++++---------
 packages/koishi-core/src/context.ts |  6 ++---
 2 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/packages/koishi-core/src/app.ts b/packages/koishi-core/src/app.ts
index f3eabb4b22..239a4a0b48 100644
--- a/packages/koishi-core/src/app.ts
+++ b/packages/koishi-core/src/app.ts
@@ -85,9 +85,7 @@ export class App extends Context {
   atMeRE: RegExp
   prefixRE: RegExp
   nicknameRE: RegExp
-  users: MajorContext
-  groups: MajorContext
-  discusses: MajorContext
+  status = Status.closed
 
   _commands: Command[] = []
   _commandMap: Record<string, Command> = {}
@@ -95,7 +93,9 @@ export class App extends Context {
   _shortcutMap: Record<string, Command> = {}
   _middlewares: [Context, Middleware][] = []
 
-  private status = Status.closed
+  private _users: MajorContext
+  private _groups: MajorContext
+  private _discusses: MajorContext
   private _isReady = false
   private _middlewareCounter = 0
   private _middlewareSet = new Set<number>()
@@ -126,14 +126,27 @@ export class App extends Context {
     this.receiver.on('before-user', Command.attachUserFields)
     this.receiver.on('before-group', Command.attachGroupFields)
     this.middleware(this._preprocess)
+  }
+
+  get users () {
+    if (this._users) return this._users
+    const users = this.createContext([[null, []], [[], null], [[], null]]) as MajorContext
+    users.except = (...ids) => this.createContext([[null, ids], [[], null], [[], null]])
+    return this._users = users
+  }
+
+  get groups () {
+    if (this._groups) return this._groups
+    const groups = this.createContext([[[], null], [null, []], [[], null]]) as MajorContext
+    groups.except = (...ids) => this.createContext([[[], null], [null, ids], [[], null]])
+    return this._groups = groups
+  }
 
-    // create built-in contexts
-    this.users = this.createContext([[null, []], [[], null], [[], null]]) as MajorContext
-    this.groups = this.createContext([[[], null], [null, []], [[], null]]) as MajorContext
-    this.discusses = this.createContext([[[], null], [[], null], [null, []]]) as MajorContext
-    this.users.except = (...ids) => this.createContext([[null, ids], [[], null], [[], null]])
-    this.groups.except = (...ids) => this.createContext([[[], null], [null, ids], [[], null]])
-    this.discusses.except = (...ids) => this.createContext([[[], null], [[], null], [null, ids]])
+  get discusses () {
+    if (this._discusses) return this._discusses
+    const discusses = this.createContext([[[], null], [[], null], [null, []]]) as MajorContext
+    discusses.except = (...ids) => this.createContext([[[], null], [[], null], [null, ids]])
+    return this._discusses = discusses
   }
 
   get selfId () {
diff --git a/packages/koishi-core/src/context.ts b/packages/koishi-core/src/context.ts
index 9cde0e2c11..18c616e773 100644
--- a/packages/koishi-core/src/context.ts
+++ b/packages/koishi-core/src/context.ts
@@ -131,11 +131,11 @@ export class Context {
   plugin <U> (plugin: PluginObject<this, U>, options?: U): this
   plugin <U> (plugin: Plugin<this, U>, options: any) {
     if (options === false) return
-    const app = Object.create(this)
+    const ctx = Object.create(this)
     if (typeof plugin === 'function') {
-      plugin(app, options)
+      plugin(ctx, options)
     } else if (plugin && typeof plugin === 'object' && typeof plugin.apply === 'function') {
-      plugin.apply(app, options)
+      plugin.apply(ctx, options)
     } else {
       throw new Error(errors.INVALID_PLUGIN)
     }