From bf8ab2dc9c2f75d7f67f25e9ffb6880598a1012b Mon Sep 17 00:00:00 2001
From: sis0k0 <stanimira.vlaeva@gmail.com>
Date: Mon, 17 Dec 2018 17:37:29 +0200
Subject: [PATCH 1/3] refactor: export safeGet from projectHelpers

---
 projectHelpers.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/projectHelpers.js b/projectHelpers.js
index 0f61b76c..ed1ffbf4 100644
--- a/projectHelpers.js
+++ b/projectHelpers.js
@@ -110,5 +110,6 @@ module.exports = {
     isTypeScript,
     writePackageJson,
     convertSlashesInPath,
-    getIndentationCharacter
+    getIndentationCharacter,
+    safeGet,
 };
\ No newline at end of file

From 8623875b0b6af535026ff96ece34588fe195047b Mon Sep 17 00:00:00 2001
From: sis0k0 <stanimira.vlaeva@gmail.com>
Date: Mon, 17 Dec 2018 17:43:27 +0200
Subject: [PATCH 2/3] test: add unit tests for safeGet

---
 projectHelpers.spec.js | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/projectHelpers.spec.js b/projectHelpers.spec.js
index c8a83b88..36425925 100644
--- a/projectHelpers.spec.js
+++ b/projectHelpers.spec.js
@@ -1,4 +1,4 @@
-const { getIndentationCharacter, writePackageJson } = require("./projectHelpers");
+const { getIndentationCharacter, writePackageJson, safeGet } = require("./projectHelpers");
 const fs = require("fs");
 
 describe('projectHelpers', () => {
@@ -57,6 +57,28 @@ describe('projectHelpers', () => {
         });
     });
 
+    describe('safeGet', () => {
+        it('should return the correct value of existing properties', () => {
+            const obj = { a: 15 };
+            expect(safeGet(obj, 'a')).toBe(15);
+        });
+
+        it('should return undefined for unexisting properties', () => {
+            const obj = { a: 15 };
+            expect(safeGet(obj, 'random')).toBeUndefined();
+        });
+
+        it('should return undefined when the first argument is undefined', () => {
+            let obj;
+            expect(safeGet(obj, 'random')).toBeUndefined();
+        });
+
+        it('should return undefined when the first argument is not an object and does not have inherited property with the queried name', () => {
+            const num = 15;
+            expect(safeGet(num, 'random')).toBeUndefined();
+        });
+    });
+
     describe('writePackageJson', () => {
         const mockFileSystemApi = () => {
             const data = {

From 95ec9ff0664346afb0d0d5fb92a27f86b751b9a1 Mon Sep 17 00:00:00 2001
From: sis0k0 <stanimira.vlaeva@gmail.com>
Date: Mon, 17 Dec 2018 17:43:37 +0200
Subject: [PATCH 3/3] fix(Angular): add hot loader for lazy loaded NgModules

---
 lazy-ngmodule-hot-loader.js  | 17 +++++++++++++++++
 templates/webpack.angular.js |  1 +
 2 files changed, 18 insertions(+)
 create mode 100644 lazy-ngmodule-hot-loader.js

diff --git a/lazy-ngmodule-hot-loader.js b/lazy-ngmodule-hot-loader.js
new file mode 100644
index 00000000..1f168c6a
--- /dev/null
+++ b/lazy-ngmodule-hot-loader.js
@@ -0,0 +1,17 @@
+const { safeGet } = require("./projectHelpers");
+
+const LAZY_RESOURCE_CONTEXT = "$$_lazy_route_resource";
+const HOT_SELF_ACCEPT = "module.hot && module.hot.accept()";
+
+const isLazyLoadedNgModule = resource => {
+    const issuer = safeGet(resource, "issuer");
+    const issuerContext = safeGet(issuer, "context");
+
+    return issuerContext && issuerContext.endsWith(LAZY_RESOURCE_CONTEXT);
+};
+
+module.exports = function (source) {
+    return isLazyLoadedNgModule(this._module) ?
+        `${source};${HOT_SELF_ACCEPT}`:
+        source;
+};
diff --git a/templates/webpack.angular.js b/templates/webpack.angular.js
index 0bd787b3..60b51071 100644
--- a/templates/webpack.angular.js
+++ b/templates/webpack.angular.js
@@ -192,6 +192,7 @@ module.exports = env => {
                     test: /(?:\.ngfactory\.js|\.ngstyle\.js|\.ts)$/,
                     use: [
                         "nativescript-dev-webpack/moduleid-compat-loader",
+                        "nativescript-dev-webpack/lazy-ngmodule-hot-loader",
                         "@ngtools/webpack",
                     ]
                 },