add test for #893

test/function/tracks-alias-mutations-b/_config.js

@@ -0,0 +1,13 @@
+const assert = require( 'assert' );
+
+const foo = {};
+
+module.exports = {
+	description: 'tracks mutations of aliased objects',
+	context: {
+		foo
+	},
+	exports () {
+		assert.equal( foo.x, 42 );
+	}
+};

test/function/tracks-alias-mutations-b/main.js

@@ -0,0 +1,2 @@
+var _foo = foo;
+_foo.x = 42;