Add prompt strategy

docs/keyring.rst

@@ -6,8 +6,7 @@ Storing passwords
 
    Password configuration got completely overhauled.
 
-Vdirsyncer can fetch passwords from a custom command or your system keyring if
-the keyring_ Python package is installed.
+Vdirsyncer can fetch passwords from several sources other than the config file.
 
 Command
 =======
@@ -53,3 +52,14 @@ Given that you have the keyring_ Python library installed, you can use::
     password.fetch = ["keyring", "myservicename", "myusername"]
 
 .. _keyring: https://pypi.python.org/pypi/keyring
+
+
+Password Prompt
+===============
+
+You can also simply prompt for the password::
+
+    [storage foo]
+    type = caldav
+    username = myusername
+    password.fetch = ["prompt", "Password for CalDAV"]

tests/cli/test_fetchparams.py

@@ -30,7 +30,7 @@ def test_get_password_from_command(tmpdir, runner):
         [storage bar]
         type = filesystem
         path = {base}/bar/
-        fileext.fetch = ["command", "echo", ".asdf"]
+        fileext.fetch = ["prompt", "Fileext for bar"]
     '''.format(base=str(tmpdir))))
 
     foo = tmpdir.ensure('foo', dir=True)
@@ -42,7 +42,7 @@ def test_get_password_from_command(tmpdir, runner):
     bar.ensure('b', dir=True)
     bar.ensure('c', dir=True)
 
-    result = runner.invoke(['discover'])
+    result = runner.invoke(['discover'], input='.asdf\n')
     assert not result.exception
     status = tmpdir.join('status').join('foobar.collections').read()
     assert 'foo' in status
@@ -50,5 +50,7 @@ def test_get_password_from_command(tmpdir, runner):
     assert 'asdf' not in status
     assert 'txt' not in status
 
-    result = runner.invoke(['sync'])
+    foo.join('a').join('foo.txt').write('BEGIN:VCARD\nUID:foo\nEND:VCARD')
+    result = runner.invoke(['sync'], input='.asdf\n')
     assert not result.exception
+    assert [x.basename for x in bar.join('a').listdir()] == ['foo.asdf']

vdirsyncer/cli/fetchparams.py

@@ -85,7 +85,12 @@ def _strategy_command(*command):
                                    .format(' '.join(command), str(e)))
 
 
+def _strategy_prompt(text):
+    return click.prompt(text, hide_input=True)
+
+
 STRATEGIES = {
     'keyring': _strategy_keyring,
-    'command': _strategy_command
+    'command': _strategy_command,
+    'prompt': _strategy_prompt,
 }