bpo-28707: Add the directory parameter to http.server.SimpleHTTPRequestHandler and http.server module (#1776)

* bpo-28707: call the constructor of SimpleHTTPRequestHandler in the test with a mock object

* bpo-28707: Add the directory parameter to http.server.SimpleHTTPRequestHandler and http.server module

Doc/library/http.server.rst

@@ -299,7 +299,7 @@ of which this module provides three different variants:
          delays, it now always returns the IP address.
 
 
-.. class:: SimpleHTTPRequestHandler(request, client_address, server)
+.. class:: SimpleHTTPRequestHandler(request, client_address, server, directory=None)
 
    This class serves files from the current directory and below, directly
    mapping the directory structure to HTTP requests.
@@ -323,6 +323,10 @@ of which this module provides three different variants:
       ``application/octet-stream``. The mapping is used case-insensitively,
       and so should contain only lower-cased keys.
 
+   .. attribute:: directory
+
+      If not specified, the directory to serve is the current working directory.
+
    The :class:`SimpleHTTPRequestHandler` class defines the following methods:
 
    .. method:: do_HEAD()
@@ -397,6 +401,14 @@ following command causes the server to bind to localhost only::
 .. versionadded:: 3.4
     ``--bind`` argument was introduced.
 
+By default, server uses the current directory. The option ``-d/--directory``
+specifies a directory to which it should serve the files. For example,
+the following command uses a specific directory::
+
+        python -m http.server --directory /tmp/
+
+.. versionadded:: 3.7
+    ``--directory`` specify alternate directory
 
 .. class:: CGIHTTPRequestHandler(request, client_address, server)
 
@@ -442,4 +454,3 @@ following command causes the server to bind to localhost only::
 the ``--cgi`` option::
 
         python -m http.server --cgi 8000
-