--- a/testing/marionette/mach_commands.py
+++ b/testing/marionette/mach_commands.py
@@ -140,22 +140,24 @@ class Marionette(MachCommandBase):
 
         srcs = [f for f in os.listdir(
             self.srcdir) if is_marionette_source_file(f)]
 
         proc = subprocess.Popen(
             ["jsdoc", "-c", ".jsdoc.js"] + srcs, cwd=self.srcdir)
         proc.wait()
 
-        if http:
+        if http and proc.returncode == 0:
             import SimpleHTTPServer
             import SocketServer
 
             host, port = http.split(":")
             host = host or "127.0.0.1"
             port = int(port)
 
             handler = SimpleHTTPServer.SimpleHTTPRequestHandler
             httpd = SocketServer.TCPServer((host, int(port)), handler)
 
             print "serving at %s:%s" % (host, port)
             os.chdir(os.path.join(self.srcdir, "doc"))
             httpd.serve_forever()
+
+        return proc.returncode