Fall back to current working directory when no entry file is specified for some reason

src/phase-streams/dedupe-bundle-css.js

@@ -16,8 +16,11 @@ module.exports = function createDedupeBundleCssStream(options) {
 	let allCss = "";
 	let loaderItem;
 
-	// Get the (absolute!) path of the folder containing the initial entry file, as a reference point for relative paths in the output
-	let entryPoint = path.dirname(path.resolve(options._flags.entries[0]));
+	let entryPoint = (options._flags.entries != null)
+		// Get the (absolute!) path of the folder containing the initial entry file, as a reference point for relative paths in the output
+		? path.dirname(path.resolve(options._flags.entries[0]))
+		// ... or, if no entry file is specified, go off the current working directory
+		: process.cwd()
 
 	return stream((item) => {
 		// And the same for the loader shim path. All this relative-path stuff is to prevent absolute filesystem URLs from leaking into the output, as those might contain sensitive information.