"""Unit tests for the keyword only argument specified in PEP 3102."""
__author__ = "Jiwon Seo"
__email__ = "seojiwon at gmail dot com"
import unittest
def posonly_sum(pos_arg1, *arg, **kwarg):
return pos_arg1 + sum(arg) + sum(kwarg.values())
def keywordonly_sum(*, k1=0, k2):
return k1 + k2
def keywordonly_nodefaults_sum(*, k1, k2):
return k1 + k2
def keywordonly_and_kwarg_sum(*, k1, k2, **kwarg):
return k1 + k2 + sum(kwarg.values())
def mixedargs_sum(a, b=0, *arg, k1, k2=0):
return a + b + k1 + k2 + sum(arg)
def mixedargs_sum2(a, b=0, *arg, k1, k2=0, **kwargs):
return a + b + k1 + k2 + sum(arg) + sum(kwargs.values())
def sortnum(*nums, reverse=False):
return sorted(list(nums), reverse=reverse)
def sortwords(*words, reverse=False, **kwargs):
return sorted(list(words), reverse=reverse)
class Foo:
def __init__(self, *, k1, k2=0):
self.k1 = k1
self.k2 = k2
def set(self, p1, *, k1, k2):
self.k1 = k1
self.k2 = k2
def sum(self):
return self.k1 + self.k2
class KeywordOnlyArgTestCase(unittest.TestCase):
def assertRaisesSyntaxError(self, codestr):
def shouldRaiseSyntaxError(s):
compile(s, "<test>", "single")
self.assertRaises(SyntaxError, shouldRaiseSyntaxError, codestr)
def testSyntaxErrorForFunctionDefinition(self):
self.assertRaisesSyntaxError("def f(p, *):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *, p1=100):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *k1, k1=100):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *, k1, k1=100):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *, **k1):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *, k1, **k1):\n pass\n")
self.assertRaisesSyntaxError("def f(p1, *, None, **k1):\n pass\n")
self.assertRaisesSyntaxError("def f(p, *, (k1, k2), **kw):\n pass\n")
def testSyntaxForManyArguments(self):
fundef = "def f("
for i in range(255):
fundef += "i%d, "%i
fundef += "*, key=100):\n pass\n"
self.assertRaisesSyntaxError(fundef)
fundef2 = "def foo(i,*,"
for i in range(255):
fundef2 += "i%d, "%i
fundef2 += "lastarg):\n pass\n"
self.assertRaisesSyntaxError(fundef2)
# exactly 255 arguments, should compile ok
fundef3 = "def f(i,*,"
for i in range(253):
fundef3 += "i%d, "%i
fundef3 += "lastarg):\n pass\n"
compile(fundef3, "<test>", "single")
def testTooManyPositionalErrorMessage(self):
def f(a, b=None, *, c=None):
pass
with self.assertRaises(TypeError) as exc:
f(1, 2, 3)
expected = "f() takes from 1 to 2 positional arguments but 3 were given"
self.assertEqual(str(exc.exception), expected)
def testSyntaxErrorForFunctionCall(self):
self.assertRaisesSyntaxError("f(p, k=1, p2)")
self.assertRaisesSyntaxError("f(p, k1=50, *(1,2), k1=100)")
def testRaiseErrorFuncallWithUnexpectedKeywordArgument(self):
self.assertRaises(TypeError, keywordonly_sum, ())
self.assertRaises(TypeError, keywordonly_nodefaults_sum, ())
self.assertRaises(TypeError, Foo, ())
try:
keywordonly_sum(k2=100, non_existing_arg=200)
self.fail("should raise TypeError")
except TypeError:
pass
try:
keywordonly_nodefaults_sum(k2=2)
self.fail("should raise TypeError")
except TypeError:
pass
def testFunctionCall(self):
self.assertEqual(1, posonly_sum(1))
self.assertEqual(1+2, posonly_sum(1,**{"2":2}))
self.assertEqual(1+2+3, posonly_sum(1,*(2,3)))
self.assertEqual(1+2+3+4, posonly_sum(1,*(2,3),**{"4":4}))
self.assertEqual(1, keywordonly_sum(k2=1))
self.assertEqual(1+2, keywordonly_sum(k1=1, k2=2))
self.assertEqual(1+2, keywordonly_and_kwarg_sum(k1=1, k2=2))
self.assertEqual(1+2+3, keywordonly_and_kwarg_sum(k1=1, k2=2, k3=3))
self.assertEqual(1+2+3+4,
keywordonly_and_kwarg_sum(k1=1, k2=2,
**{"a":3,"b":4}))
self.assertEqual(1+2, mixedargs_sum(1, k1=2))
self.assertEqual(1+2+3, mixedargs_sum(1, 2, k1=3))
self.assertEqual(1+2+3+4, mixedargs_sum(1, 2, k1=3, k2=4))
self.assertEqual(1+2+3+4+5, mixedargs_sum(1, 2, 3, k1=4, k2=5))
self.assertEqual(1+2, mixedargs_sum2(1, k1=2))
self.assertEqual(1+2+3, mixedargs_sum2(1, 2, k1=3))
self.assertEqual(1+2+3+4, mixedargs_sum2(1, 2, k1=3, k2=4))
self.assertEqual(1+2+3+4+5, mixedargs_sum2(1, 2, 3, k1=4, k2=5))
self.assertEqual(1+2+3+4+5+6,
mixedargs_sum2(1, 2, 3, k1=4, k2=5, k3=6))
self.assertEqual(1+2+3+4+5+6,
mixedargs_sum2(1, 2, 3, k1=4, **{'k2':5, 'k3':6}))
self.assertEqual(1, Foo(k1=1).sum())
self.assertEqual(1+2, Foo(k1=1,k2=2).sum())
self.assertEqual([1,2,3], sortnum(3,2,1))
self.assertEqual([3,2,1], sortnum(1,2,3, reverse=True))
self.assertEqual(['a','b','c'], sortwords('a','c','b'))
self.assertEqual(['c','b','a'], sortwords('a','c','b', reverse=True))
self.assertEqual(['c','b','a'],
sortwords('a','c','b', reverse=True, ignore='ignore'))
def testKwDefaults(self):
def foo(p1,p2=0, *, k1, k2=0):
return p1 + p2 + k1 + k2
self.assertEqual(2, foo.__code__.co_kwonlyargcount)
self.assertEqual({"k2":0}, foo.__kwdefaults__)
foo.__kwdefaults__ = {"k1":0}
try:
foo(1,k1=10)
self.fail("__kwdefaults__ is not properly changed")
except TypeError:
pass
def test_kwonly_methods(self):
class Example:
def f(self, *, k1=1, k2=2):
return k1, k2
self.assertEqual(Example().f(k1=1, k2=2), (1, 2))
self.assertEqual(Example.f(Example(), k1=1, k2=2), (1, 2))
self.assertRaises(TypeError, Example.f, k1=1, k2=2)
def test_issue13343(self):
# The Python compiler must scan all symbols of a function to
# determine their scope: global, local, cell...
# This was not done for the default values of keyword
# arguments in a lambda definition, and the following line
# used to fail with a SystemError.
lambda *, k1=unittest: None
def test_mangling(self):
class X:
def f(self, *, __a=42):
return __a
self.assertEqual(X().f(), 42)
def test_default_evaluation_order(self):
# See issue 16967
a = 42
with self.assertRaises(NameError) as err:
def f(v=a, x=b, *, y=c, z=d):
pass
self.assertEqual(str(err.exception), "name 'b' is not defined")
with self.assertRaises(NameError) as err:
f = lambda v=a, x=b, *, y=c, z=d: None
self.assertEqual(str(err.exception), "name 'b' is not defined")
if __name__ == "__main__":
unittest.main()