Parse command arguments using a decorator and make things more consistent

Avoid surprises with some commands accepting quoted arguments and some other
not.

fix #2555

1 files changed, 92 insertions, 0 deletions

diff --git a/src/decorators.py b/src/decorators.py
index 251d8749..627d8f59 100644
--- a/src/decorators.py
+++ b/src/decorators.py
@@ -2,6 +2,8 @@
 Module containing various decorators
 """
 
+import common
+
 class RefreshWrapper(object):
     def __init__(self):
         self.core = None
@@ -41,3 +43,93 @@ class RefreshWrapper(object):
         return wrap
 
 refresh_wrapper = RefreshWrapper()
+
+class CommandArgParser(object):
+    """Modify the string argument of the function into a list of strings
+    containing the right number of extracted arguments, or None if we don’t
+    have enough.
+    """
+    @staticmethod
+    def raw(func):
+        """Just call the function with a single string, which is the original string
+        untouched
+        """
+        def wrap(self, args, *a, **kw):
+            return func(self, args, *a, **kw)
+        return wrap
+
+    @staticmethod
+    def ignored(func):
+        """
+        Call the function without any argument
+        """
+        def wrap(self, args, *a, **kw):
+            return func(self, *a, **kw)
+        return wrap
+
+    @staticmethod
+    def quoted(mandatory, optional=0, defaults=[],
+               ignore_trailing_arguments=False):
+
+        """The function receives a list with a number of arguments that is between
+        the numbers `mandatory` and `optional`.
+
+        If the string doesn’t contain at least `mandatory` arguments, we return
+        None because the given arguments  are invalid.
+
+        If there are any remaining arguments after `mandatory` and `optional`
+        arguments have been found (and “ignore_trailing_arguments" is not True),
+        we happen them to the last argument of the list.
+
+        An argument is a string (with or without whitespaces) between to quotes
+        ("), or a whitespace separated word (if not inside quotes).
+
+        The argument `defaults` is a list of strings that are used when an
+        optional argument is missing.  For example if we accept one optional
+        argument, zero is available but we have one value in the `defaults`
+        list, we use that string inplace. The `defaults` list can only
+        replace missing optional arguments, not mandatory ones. And it
+        should not contain more than `mandatory` values. Also you cannot
+
+        Example:
+        This method needs at least one argument, and accepts up to 3
+        arguments
+
+        >> @command_args_parser.quoted(1, 2, ['default for first arg'], False)
+        >> def f(args):
+        >>     print(args)
+
+        >> f('coucou les amis') # We have one mandatory and two optional
+        ['coucou', 'les', 'amis']
+        >> f('"coucou les amis" "PROUT PROUT"') # One mandator and only one optional,
+                                                # no default for the second
+        ['coucou les amis', 'PROUT PROUT']
+        >> f('')                # Not enough args for mandatory number
+        None
+        >> f('"coucou les potes"') # One mandatory, and use the default value
+                                   # for the first optional
+        ['coucou les potes, 'default for first arg']
+        >> f('"un et demi" deux trois quatre cinq six') # We have three trailing arguments
+        ['un et demi', 'deux', 'trois quatre cinq six']
+
+        """
+        def first(func):
+            def second(self, args, *a, **kw):
+                default_args = defaults
+                args = common.shell_split(args)
+                if len(args) < mandatory:
+                    return func(self, None, *a, **kw)
+                res, args = args[:mandatory], args[mandatory:]
+                opt_args = args[:optional]
+                if opt_args:
+                    res += opt_args
+                    args = args[len(opt_args):]
+                    default_args = default_args[len(opt_args):]
+                res += default_args
+                if args and res and not ignore_trailing_arguments:
+                    res[-1] += " " + " ".join(args)
+                return func(self, res, *a, **kw)
+            return second
+        return first
+
+command_args_parser = CommandArgParser()