chore(core): monorepo, esm targeting, improved management (#8707)

packages/webpack/helpers/lazy-ngmodule-hot-loader.js

@@ -0,0 +1,30 @@
+const { safeGet } = require("./projectHelpers");
+
+const LAZY_RESOURCE_CONTEXT = "$$_lazy_route_resource";
+const HOT_SELF_ACCEPT = "module.hot.accept();";
+const HOT_DISPOSE = `
+        module.hot.dispose(() => {
+            // Currently the context is needed only for application style modules.
+            const moduleContext = {};
+            global.hmrRefresh(moduleContext);
+        });`;
+const HMR_HANDLER = `
+    if (module.hot) {
+        ${HOT_SELF_ACCEPT}${HOT_DISPOSE}
+    }
+`;
+
+const isLazyLoadedNgModule = resource => {
+    const issuer = safeGet(resource, "issuer");
+    const issuerContext = safeGet(issuer, "context");
+
+    return issuerContext && issuerContext.endsWith(LAZY_RESOURCE_CONTEXT);
+};
+
+module.exports = function (source, map) {
+    const modifiedSource = isLazyLoadedNgModule(this._module) ?
+        `${source};${HMR_HANDLER}`:
+        source;
+
+    this.callback(null, modifiedSource, map);
+};