add sample for microsoft/TypeScript#2784

Author: basarat

errorcases/reopenExternalModules/a.d.ts

@@ -0,0 +1,7 @@
+declare module "foo" {
+    interface Foo {
+        a: number;
+    }
+    var _:Foo;
+    export = _;
+}

errorcases/reopenExternalModules/b.d.ts

@@ -0,0 +1,7 @@
+/// <reference path="./a"/>
+
+declare module "foo" {
+    interface Foo {
+        b: number;
+    }
+}

errorcases/reopenExternalModules/test.js

@@ -0,0 +1,4 @@
+/// <reference path="./a"/>
+/// <reference path="./b"/>
+var foo = require("foo");
+foo.b = 123;

errorcases/reopenExternalModules/test.ts

@@ -0,0 +1,5 @@
+/// <reference path="./a"/>
+/// <reference path="./b"/>
+
+import foo = require("foo");
+foo.b = 123; // ERROR: Property b to not exist on type Foo

errorcases/reopenExternalModules/tsconfig.json

@@ -0,0 +1,20 @@
+{
+    "version": "1.4.1",
+    "compilerOptions": {
+        "target": "es5",
+        "module": "commonjs",
+        "declaration": false,
+        "noImplicitAny": false,
+        "removeComments": true,
+        "noLib": false
+    },
+    "filesGlob": [
+        "./**/*.ts",
+        "!./node_modules/**/*.ts"
+    ],
+    "files": [
+        "./a.d.ts",
+        "./b.d.ts",
+        "./test.ts"
+    ]
+}