Add reproduction of runtime decorators error

.eslintrc.js

@@ -1,5 +1,6 @@
 module.exports = {
   root: true,
+  parser: 'babel-eslint',
   parserOptions: {
     ecmaVersion: 2017,
     sourceType: 'module'

app/config/environment.d.ts

@@ -0,0 +1,16 @@
+export default config;
+
+/**
+ * Type declarations for
+ *    import config from './config/environment'
+ *
+ * For now these need to be managed by the developer
+ * since different ember addons can materialize new entries.
+ */
+declare const config: {
+  environment: any;
+  modulePrefix: string;
+  podModulePrefix: string;
+  locationType: string;
+  rootURL: string;
+};

app/controllers/application.ts

@@ -0,0 +1,16 @@
+import Controller from '@ember/controller';
+import { inject as service } from '@ember-decorators/service';
+import Router from '@ember/routing/router';
+
+export default class ApplicationController extends Controller {
+  @service
+  router!: Router;
+
+  foo(bar: string[]): void;
+  foo(bar: string): void;
+  foo() {
+    // dummy
+  }
+
+
+}

package.json

@@ -18,8 +18,18 @@
     "test": "ember test"
   },
   "devDependencies": {
+    "@ember-decorators/babel-transforms": "^3.1.0",
     "@ember/jquery": "^0.5.2",
     "@ember/optional-features": "^0.6.3",
+    "@types/ember": "^3.0.27",
+    "@types/ember-data": "^3.1.3",
+    "@types/ember-qunit": "^3.4.5",
+    "@types/ember-test-helpers": "^1.0.4",
+    "@types/ember-testing-helpers": "^0.0.3",
+    "@types/ember__test-helpers": "^0.7.7",
+    "@types/qunit": "^2.5.4",
+    "@types/rsvp": "^4.0.2",
+    "babel-eslint": "^8.0.0",
     "broccoli-asset-rev": "^2.7.0",
     "ember-ajax": "^3.1.0",
     "ember-cli": "~3.7.0",
@@ -32,8 +42,11 @@
     "ember-cli-inject-live-reload": "^1.8.2",
     "ember-cli-sri": "^2.1.1",
     "ember-cli-template-lint": "^1.0.0-beta.1",
+    "ember-cli-typescript": "^2.0.0-rc.2",
+    "ember-cli-typescript-blueprints": "^2.0.0-beta.1",
     "ember-cli-uglify": "^2.1.0",
     "ember-data": "~3.7.0",
+    "ember-decorators": "^5.1.3",
     "ember-export-application-global": "^2.0.0",
     "ember-load-initializers": "^1.1.0",
     "ember-maybe-import-regenerator": "^0.1.6",
@@ -43,7 +56,8 @@
     "ember-welcome-page": "^3.2.0",
     "eslint-plugin-ember": "^5.2.0",
     "loader.js": "^4.7.0",
-    "qunit-dom": "^0.8.0"
+    "qunit-dom": "^0.8.0",
+    "typescript": "^3.3.3333"
   },
   "engines": {
     "node": "6.* || 8.* || >= 10.*"

tsconfig.json

@@ -0,0 +1,40 @@
+{
+  "compilerOptions": {
+    "target": "es2017",
+    "allowJs": true,
+    "moduleResolution": "node",
+    "allowSyntheticDefaultImports": true,
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "strictNullChecks": true,
+    "strictPropertyInitialization": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noImplicitReturns": true,
+    "noEmitOnError": false,
+    "noEmit": true,
+    "inlineSourceMap": true,
+    "inlineSources": true,
+    "baseUrl": ".",
+    "module": "es6",
+    "experimentalDecorators": true,
+    "paths": {
+      "ember-typescript-overloads-decorators-bug/tests/*": [
+        "tests/*"
+      ],
+      "ember-typescript-overloads-decorators-bug/*": [
+        "app/*"
+      ],
+      "*": [
+        "types/*"
+      ]
+    }
+  },
+  "include": [
+    "app/**/*",
+    "tests/**/*",
+    "types/**/*"
+  ]
+}

types/ember-data/types/registries/model.d.ts

@@ -0,0 +1,6 @@
+/**
+ * Catch-all for ember-data.
+ */
+export default interface ModelRegistry {
+  [key: string]: any;
+}

types/ember-typescript-overloads-decorators-bug/index.d.ts

@@ -0,0 +1,10 @@
+
+import Ember from 'ember';
+
+declare global {
+  interface Array<T> extends Ember.ArrayPrototypeExtensions<T> {}
+  // interface Function extends Ember.FunctionPrototypeExtensions {}
+}
+
+export {};
+