Test detecting generated source maps

test/fixtures/Data/sourcemap.v1.map

@@ -0,0 +1,12 @@
+/** Begin line maps. **/{ “file”:”out.js”, "count": 2 }
+[0,0,0,0,0,0,1,1,1,1,2]
+[2,2,2,2,2,2,3,4,4,4,4,4]
+/** Begin file information. **/
+[“a.js”, “b.js”]
+[“b.js”, “c.js”, “d.js”]
+/** Begin mapping definitions. **/
+["a.js", 1, 34]
+["a.js", 5, 2]
+["b.js", 1, 3, "event"]
+["c.js", 1, 4]
+["d.js", 3, 78, "foo"]