#
#
-# Copyright (C) 2010, 2011 Google Inc.
+# Copyright (C) 2010, 2011, 2012 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
return "(%s)" % text
-class _DescWrapper(object):
+class _WrapperBase(object):
__slots__ = [
"_fn",
"_text",
@param fn: Wrapped function
"""
+ assert text.strip()
+
self._text = text
self._fn = fn
def __call__(self, *args):
return self._fn(*args)
+
+class _DescWrapper(_WrapperBase):
+ """Wrapper class for description text.
+
+ """
def __str__(self):
return self._text
+class _CommentWrapper(_WrapperBase):
+ """Wrapper class for comment.
+
+ """
+ def __str__(self):
+ return "%s [%s]" % (self._fn, self._text)
+
+
def WithDesc(text):
"""Builds wrapper class with description text.
return compat.partial(_DescWrapper, text)
+def Comment(text):
+ """Builds wrapper for adding comment to description text.
+
+ @type text: string
+ @param text: Comment text
+ @return: Callable class
+
+ """
+ assert not frozenset(text).intersection("[]")
+
+ return compat.partial(_CommentWrapper, text)
+
+
def CombinationDesc(op, args, fn):
"""Build description for combinating operator.
@param fn: Wrapped function
"""
+ # Some type descriptions are rather long. If "None" is listed at the
+ # end or somewhere in between it is easily missed. Therefore it should
+ # be at the beginning, e.g. "None or (long description)".
+ if __debug__ and TNone in args and args.index(TNone) > 0:
+ raise Exception("TNone must be listed first")
+
if len(args) == 1:
descr = str(args[0])
else:
return val is None
+@WithDesc("ValueNone")
+def TValueNone(val):
+ """Checks if the given value is L{constants.VALUE_NONE}.
+
+ """
+ return val == constants.VALUE_NONE
+
+
@WithDesc("Boolean")
def TBool(val):
"""Checks if the given value is a boolean.
return isinstance(val, list)
+@WithDesc("Tuple")
+def TTuple(val):
+ """Checks if the given value is a tuple.
+
+ """
+ return isinstance(val, tuple)
+
+
@WithDesc("Dictionary")
def TDict(val):
"""Checks if the given value is a dictionary.
return desc(TAnd(TString, pobj.match))
+def TMaybe(test):
+ """Wrap a test in a TOr(TNone, test).
+
+ This makes it easier to define TMaybe* types.
+
+ """
+ return TOr(TNone, test)
+
+
+def TMaybeValueNone(test):
+ """Used for unsetting values.
+
+ """
+ return TMaybe(TOr(TValueNone, test))
+
+
# Type aliases
#: a non-empty string
TNonEmptyString = WithDesc("NonEmptyString")(TAnd(TString, TTrue))
#: a maybe non-empty string
-TMaybeString = TOr(TNonEmptyString, TNone)
+TMaybeString = TMaybe(TNonEmptyString)
#: a maybe boolean (bool or none)
-TMaybeBool = TOr(TBool, TNone)
+TMaybeBool = TMaybe(TBool)
#: Maybe a dictionary (dict or None)
-TMaybeDict = TOr(TDict, TNone)
+TMaybeDict = TMaybe(TDict)
-#: a positive integer
-TPositiveInt = \
- TAnd(TInt, WithDesc("EqualGreaterZero")(lambda v: v >= 0))
+#: a non-negative integer (value >= 0)
+TNonNegativeInt = \
+ TAnd(TInt, WithDesc("EqualOrGreaterThanZero")(lambda v: v >= 0))
-#: a strictly positive integer
-TStrictPositiveInt = \
+#: a positive integer (value > 0)
+TPositiveInt = \
TAnd(TInt, WithDesc("GreaterThanZero")(lambda v: v > 0))
-#: a strictly negative integer (0 > value)
-TStrictNegativeInt = \
+#: a maybe positive integer (positive integer or None)
+TMaybePositiveInt = TMaybe(TPositiveInt)
+
+#: a negative integer (value < 0)
+TNegativeInt = \
TAnd(TInt, WithDesc("LessThanZero")(compat.partial(operator.gt, 0)))
#: a positive float
-TPositiveFloat = \
- TAnd(TFloat, WithDesc("EqualGreaterZero")(lambda v: v >= 0.0))
+TNonNegativeFloat = \
+ TAnd(TFloat, WithDesc("EqualOrGreaterThanZero")(lambda v: v >= 0.0))
#: Job ID
-TJobId = TOr(TPositiveInt,
- TRegex(re.compile("^%s$" % constants.JOB_ID_TEMPLATE)))
+TJobId = WithDesc("JobId")(TOr(TNonNegativeInt,
+ TRegex(re.compile("^%s$" %
+ constants.JOB_ID_TEMPLATE))))
#: Number
TNumber = TOr(TInt, TFloat)
#: Relative job ID
-TRelativeJobId = WithDesc("RelativeJobId")(TStrictNegativeInt)
+TRelativeJobId = WithDesc("RelativeJobId")(TNegativeInt)
+
+
+def TInstanceOf(cls):
+ """Checks if a given value is an instance of C{cls}.
+
+ @type cls: class
+ @param cls: Class object
+
+ """
+ name = "%s.%s" % (cls.__module__, cls.__name__)
+
+ desc = WithDesc("Instance of %s" % (Parens(name), ))
+
+ return desc(lambda val: isinstance(val, cls))
def TListOf(my_type):
return desc(TAnd(TList, lambda lst: compat.all(my_type(v) for v in lst)))
+TMaybeListOf = lambda item_type: TMaybe(TListOf(item_type))
+
+
def TDictOf(key_type, val_type):
"""Checks a dict type for the type of its key/values.