diff --git a/test/function/handles-stringified-sourcemaps/_config.js b/test/function/handles-stringified-sourcemaps/_config.js
new file mode 100644
index 0000000..a0220e9
--- /dev/null
+++ b/test/function/handles-stringified-sourcemaps/_config.js
@@ -0,0 +1,18 @@
+module.exports = {
+	options: {
+		plugins: [
+			{
+				transform: function ( code ) {
+					return {
+						code: code,
+						map: JSON.stringify({ mappings: '' })
+					};
+				}
+			}
+		]
+	},
+
+	bundleOptions: {
+		sourceMap: true
+	}
+};
diff --git a/test/function/handles-stringified-sourcemaps/main.js b/test/function/handles-stringified-sourcemaps/main.js
new file mode 100644
index 0000000..7a4e8a7
--- /dev/null
+++ b/test/function/handles-stringified-sourcemaps/main.js
@@ -0,0 +1 @@
+export default 42;