5 files changed, 119 insertions, 7 deletions

diff --git a/src/mailman/commands/cli_withlist.py b/src/mailman/commands/cli_withlist.py
index 7e64e921a..79dc3b966 100644
--- a/src/mailman/commands/cli_withlist.py
+++ b/src/mailman/commands/cli_withlist.py
@@ -20,6 +20,7 @@
 import re
 import sys
 
+from contextlib import ExitStack
 from functools import partial
 from lazr.config import as_boolean
 from mailman import public
@@ -29,6 +30,7 @@ from mailman.interfaces.command import ICLISubCommand
 from mailman.interfaces.listmanager import IListManager
 from mailman.utilities.interact import DEFAULT_BANNER, interact
 from mailman.utilities.modules import call_name
+from string import Template
 from traceback import print_exc
 from zope.component import getUtility
 from zope.interface import implementer
@@ -164,7 +166,16 @@ class Withlist:
                 commit=config.db.commit,
                 abort=config.db.abort,
                 config=config,
+                getUtility=getUtility
                 )
+            # Bootstrap some useful names into the namespace, mostly to make
+            # the component architecture and interfaces easily available.
+            for module_name in sys.modules:
+                if not module_name.startswith('mailman.interfaces.'):
+                    continue
+                module = sys.modules[module_name]
+                for name in module.__all__:
+                    overrides[name] = getattr(module, name)
             banner = config.shell.banner + '\n' + (
                 banner if isinstance(banner, str) else '')
             try:
@@ -194,13 +205,32 @@ class Withlist:
 
     def _start_python(self, overrides, banner):
         # Set the tab completion.
-        try:
-            import readline, rlcompleter            # noqa
-            readline.parse_and_bind('tab: complete')
-        except ImportError:
-            pass
-        sys.ps1 = config.shell.prompt + ' '
-        interact(upframe=False, banner=banner, overrides=overrides)
+        with ExitStack() as resources:
+            try:                                    # pragma: no cover
+                import readline, rlcompleter        # noqa
+            except ImportError:                     # pragma: no cover
+                print(_('readline not available'), file=sys.stderr)
+                pass
+            else:
+                readline.parse_and_bind('tab: complete')
+                history_file_template = config.shell.history_file.strip()
+                if len(history_file_template) > 0:
+                    # Expand substitutions.
+                    substitutions = {
+                        key.lower(): getattr(config, key)
+                        for key in dir(config) if key.endswith('_DIR')
+                        }
+                    history_file = Template(
+                        history_file_template).safe_substitute(substitutions)
+                    try:
+                        readline.read_history_file(history_file)
+                    except FileNotFoundError:
+                        pass
+                    resources.callback(
+                        readline.write_history_file,
+                        history_file)
+            sys.ps1 = config.shell.prompt + ' '
+            interact(upframe=False, banner=banner, overrides=overrides)
 
     def _details(self):
         """Print detailed usage."""
diff --git a/src/mailman/commands/docs/conf.rst b/src/mailman/commands/docs/conf.rst
index 1db85918f..f465aab53 100644
--- a/src/mailman/commands/docs/conf.rst
+++ b/src/mailman/commands/docs/conf.rst
@@ -33,6 +33,7 @@ You can list all the key-value pairs of a specific section.
     >>> FakeArgs.section = 'shell'
     >>> command.process(FakeArgs)
     [shell] banner: Welcome to the GNU Mailman shell
+    [shell] history_file:
     [shell] prompt: >>>
     [shell] use_ipython: no
 
diff --git a/src/mailman/commands/tests/test_shell.py b/src/mailman/commands/tests/test_shell.py
new file mode 100644
index 000000000..153591f5a
--- /dev/null
+++ b/src/mailman/commands/tests/test_shell.py
@@ -0,0 +1,74 @@
+# Copyright (C) 2016 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Test the withlist/shell command."""
+
+import os
+import unittest
+
+from mailman.commands.cli_withlist import Withlist
+from mailman.config import config
+from mailman.interfaces.usermanager import IUserManager
+from mailman.testing.helpers import configuration
+from mailman.testing.layers import ConfigLayer
+from unittest.mock import patch
+
+
+class FakeArgs:
+    interactive = None
+    run = None
+    details = False
+    listname = None
+
+
+class TestShell(unittest.TestCase):
+    layer = ConfigLayer
+
+    def setUp(self):
+        self._shell = Withlist()
+
+    def test_namespace(self):
+        args = FakeArgs()
+        args.interactive = True
+        with patch.object(self._shell, '_start_python') as mock:
+            self._shell.process(args)
+        self.assertEqual(mock.call_count, 1)
+        # Don't test that all names are available, just a few choice ones.
+        positional, keywords = mock.call_args
+        namespace = positional[0]
+        self.assertIn('getUtility', namespace)
+        self.assertIn('IArchiver', namespace)
+        self.assertEqual(namespace['IUserManager'], IUserManager)
+
+    @configuration('shell', banner='my banner')
+    def test_banner(self):
+        args = FakeArgs()
+        args.interactive = True
+        with patch('mailman.commands.cli_withlist.interact') as mock:
+            self._shell.process(args)
+        self.assertEqual(mock.call_count, 1)
+        positional, keywords = mock.call_args
+        self.assertEqual(keywords['banner'], 'my banner\n')
+
+    @configuration('shell', history_file='$var_dir/history.py')
+    def test_history_file(self):
+        args = FakeArgs()
+        args.interactive = True
+        with patch('mailman.commands.cli_withlist.interact'):
+            self._shell.process(args)
+        history_file = os.path.join(config.VAR_DIR, 'history.py')
+        self.assertTrue(os.path.exists(history_file))
diff --git a/src/mailman/config/schema.cfg b/src/mailman/config/schema.cfg
index f00cc5e29..1cc209e73 100644
--- a/src/mailman/config/schema.cfg
+++ b/src/mailman/config/schema.cfg
@@ -89,6 +89,10 @@ banner: Welcome to the GNU Mailman shell
 # that any import errors will be displayed to stderr.
 use_ipython: no
 
+# Set this to allow for command line history if readline is available.  This
+# can be as simple as $var_dir/history.py to put the file in the var directory.
+history_file:
+
 
 [paths.master]
 # Important directories for Mailman operation.  These are defined here so that
diff --git a/src/mailman/docs/NEWS.rst b/src/mailman/docs/NEWS.rst
index b8362048d..ec71afc9f 100644
--- a/src/mailman/docs/NEWS.rst
+++ b/src/mailman/docs/NEWS.rst
@@ -97,6 +97,9 @@ Command line
  * ``mailman`` subcommands now properly commit any outstanding transactions.
    (Closes #223)
  * ``mailman digests`` has grown ``--verbose`` and ``-dry-run`` options.
+ * ``mailman shell`` now supports readline history if you set the
+   ``[shell]history_file`` variable in mailman.cfg.  Also, many useful names
+   are pre-populated in the namespace of the shell.  (Closes: #228)
 
 Interfaces
 ----------