npm and error messages

node_modules/css-loader/lib/url/escape.js

@@ -0,0 +1,16 @@
+module.exports = function escape(url) {
+    if (typeof url !== 'string') {
+        return url
+    }
+    // If url is already wrapped in quotes, remove them
+    if (/^['"].*['"]$/.test(url)) {
+        url = url.slice(1, -1);
+    }
+    // Should url be wrapped?
+    // See https://drafts.csswg.org/css-values-3/#urls
+    if (/["'() \t\n]/.test(url)) {
+        return '"' + url.replace(/"/g, '\\"').replace(/\n/g, '\\n') + '"'
+    }
+
+    return url
+}