"""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, "", "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, "", "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()