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

packages/webpack/helpers/apply-css-loader.js

@@ -0,0 +1,43 @@
+const cssLoaderWarning = "The apply-css-loader expects the file to be pre-processed by css-loader. It might not work properly. Please check your webpack configuration";
+
+function checkForCssLoader(loaders, loaderIndex) {
+    if (!loaders) {
+        return false;
+    }
+
+    for (var i = loaderIndex + 1; i < loaders.length; i++) {
+        const loader = loaders[i];
+        if (loader.path && loader.path.indexOf("css-loader") > 0) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+module.exports = function (content, map) {
+    if (this.request.match(/\/app\.(css|scss|less|sass)$/)) {
+        return content;
+    }
+
+    // Emit a warning if the file was not processed by the css-loader.
+    if (!checkForCssLoader(this.loaders, this.loaderIndex)) {
+        this.emitWarning(new Error(cssLoaderWarning));
+    }
+
+    content += `
+    const nsCore = require("@nativescript/core");
+    require("@nativescript/core/ui/styling/style-scope");
+
+    if (typeof exports.forEach === "function") {
+        exports.forEach(cssExport => {
+            if (cssExport.length > 1 && cssExport[1]) {
+                // applying the second item of the export as it contains the css contents
+                nsCore.Application.addCss(cssExport[1]);
+            }
+        });
+    }
+`;
+
+    this.callback(null, content, map);
+}