Issue 14989: http.server --cgi option can enable the CGI http server.
diff --git a/Lib/http/server.py b/Lib/http/server.py
index cb66f2b..c4ac703 100644
--- a/Lib/http/server.py
+++ b/Lib/http/server.py
@@ -100,6 +100,8 @@
 import time
 import urllib.parse
 import copy
+import argparse
+
 
 # Default error message template
 DEFAULT_ERROR_MESSAGE = """\
@@ -1173,18 +1175,13 @@
 
 
 def test(HandlerClass = BaseHTTPRequestHandler,
-         ServerClass = HTTPServer, protocol="HTTP/1.0"):
+         ServerClass = HTTPServer, protocol="HTTP/1.0", port=8000):
     """Test the HTTP request handler class.
 
     This runs an HTTP server on port 8000 (or the first command line
     argument).
 
     """
-
-    if sys.argv[1:]:
-        port = int(sys.argv[1])
-    else:
-        port = 8000
     server_address = ('', port)
 
     HandlerClass.protocol_version = protocol
@@ -1200,4 +1197,15 @@
         sys.exit(0)
 
 if __name__ == '__main__':
-    test(HandlerClass=SimpleHTTPRequestHandler)
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--cgi', action='store_true',
+                       help='Run as CGI Server')
+    parser.add_argument('port', action='store',
+                        default=8000, type=int,
+                        nargs='?',
+                        help='Specify alternate port [default: 8000]')
+    args = parser.parse_args()
+    if args.cgi:
+        test(HandlerClass=CGIHTTPRequestHandler, port=args.port)
+    else:
+        test(HandlerClass=SimpleHTTPRequestHandler, port=args.port)