diff --git a/lib/create-runner.js b/lib/create-runner.js
index <HASH>..<HASH> 100644
--- a/lib/create-runner.js
+++ b/lib/create-runner.js
@@ -104,8 +104,8 @@ export default function createRunner(options = {}, configFunc) {
 			const atomHome = temp.mkdirSync({ prefix: "atom-test-home-" });
 			if (options.testPackages.length > 0) {
 				let { testPackages } = options;
-				if (typeof options.testPackages === "string") {
-					testPackages = options.testPackage.split(/\s+/);
+				if (typeof testPackages === "string") {
+					testPackages = testPackages.split(/\s+/);
 				}
 				// eslint-disable-next-line no-sync
 				fs.makeTreeSync(path.join(atomHome, "packages"));
fix(testPackages): Fix `testPackages` as string