diff --git a/webpack/webpack-env-tests.ts b/webpack/webpack-env-tests.ts
index 25ec177d69..f219a3e740 100644
--- a/webpack/webpack-env-tests.ts
+++ b/webpack/webpack-env-tests.ts
@@ -37,6 +37,44 @@ if(module.hot) {
     });
 }
 
+class ModuleData {
+    updated: boolean;
+}
+
+if (module.hot) {
+    module.hot.accept((err: Error) => {
+       //...
+    });
+
+    module.hot.decline("./someModule");
+
+    module.hot.dispose((data: ModuleData) => {
+        data.updated = true;
+        // ...
+    });
+
+    let disposeHandler: ((data: ModuleData) => void) = data => {
+        // ...
+    };
+    module.hot.addDisposeHandler(disposeHandler);
+    module.hot.removeDisposeHandler(disposeHandler);
+
+    module.hot.check(true, (err: Error, outdatedModules: (string|number)[]) => {
+       // ...
+    });
+
+    module.hot.apply({ ignoreUnaccepted: true }, (err: Error, outdatedModules: (string|number)[]) => {
+        // ...
+    });
+
+    var status: string = module.hot.status();
+    let statusHandler: ((status: string) => void) = status => {
+        // ...
+    };
+    module.hot.status(statusHandler);
+    module.hot.addStatusHandler(statusHandler);
+    module.hot.removeStatusHandler(statusHandler);
+}
+
 
-var status: string = module.hot.status();
 
diff --git a/webpack/webpack-env.d.ts b/webpack/webpack-env.d.ts
index 72022c16e4..04580949b4 100644
--- a/webpack/webpack-env.d.ts
+++ b/webpack/webpack-env.d.ts
@@ -172,11 +172,11 @@ declare namespace __WebpackModuleApi {
         /**
          * If true the update process continues even if some modules are not accepted (and would bubble to the entry point).
          */
-        ignoreUnaccepted: boolean;
+        ignoreUnaccepted?: boolean;
         /**
          * Indicates that apply() is automatically called by check function
          */
-        autoApply: boolean;
+        autoApply?: boolean;
   }
 }