chore(typings): add EggLoader interface (#221)

* chore(typings): add EggLoader interface

* add generics constraint

Author: monkindey

index.d.ts

@@ -362,14 +362,19 @@ export interface ContextLoader {
   new (options: ContextLoaderOption): ContextLoaderBase;
 }
 
-export class EggLoader<T = EggCore, Config = any> {
+export class EggLoader<
+  T extends EggCore = EggCore,
+  Config = any,
+  Options extends EggLoaderOptions = EggLoaderOptions
+> {
   app: T;
   eggPaths: string[];
   pkg: PlainObject;
   appInfo: EggAppInfo;
   serverScope: string;
   plugins: Plugins;
   config: Config;
+  options: Options;
 
   /**
    * @constructor
@@ -429,6 +434,10 @@ export class EggLoader<T = EggCore, Config = any> {
    */
   getLoadUnits(): Array<{ path: string; type: string; }>;
 
+  getEggPaths(): string[];
+
+  getServerEnv(): string;
+
   /**
    * Load files using {@link FileLoader}, inject to {@link Application}
    * @param {String|Array} directory - see {@link FileLoader}