npm and error messages

node_modules/webpack/lib/ContextExclusionPlugin.js

@@ -0,0 +1,17 @@
+"use strict";
+
+class ContextExclusionPlugin {
+	constructor(negativeMatcher) {
+		this.negativeMatcher = negativeMatcher;
+	}
+
+	apply(compiler) {
+		compiler.plugin("context-module-factory", (cmf) => {
+			cmf.plugin("context-module-files", (files) => {
+				return files.filter(filePath => !this.negativeMatcher.test(filePath));
+			});
+		});
+	}
+}
+
+module.exports = ContextExclusionPlugin;