Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 1 | import unittest |
Benjamin Peterson | 2943cdb | 2013-05-11 16:10:52 -0500 | [diff] [blame] | 2 | import weakref |
| 3 | |
Zachary Ware | 38c707e | 2015-04-13 15:00:43 -0500 | [diff] [blame] | 4 | from test.support import check_syntax_error, cpython_only |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 5 | |
Jeremy Hylton | cd73836 | 2001-08-07 16:38:19 +0000 | [diff] [blame] | 6 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 7 | class ScopeTests(unittest.TestCase): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 8 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 9 | def testSimpleNesting(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 10 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 11 | def make_adder(x): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 12 | def adder(y): |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 13 | return x + y |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 14 | return adder |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 15 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 16 | inc = make_adder(1) |
| 17 | plus10 = make_adder(10) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 18 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 19 | self.assertEqual(inc(1), 2) |
| 20 | self.assertEqual(plus10(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 21 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 22 | def testExtraNesting(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 23 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 24 | def make_adder2(x): |
| 25 | def extra(): # check freevars passing through non-use scopes |
| 26 | def adder(y): |
| 27 | return x + y |
| 28 | return adder |
| 29 | return extra() |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 30 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 31 | inc = make_adder2(1) |
| 32 | plus10 = make_adder2(10) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 33 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 34 | self.assertEqual(inc(1), 2) |
| 35 | self.assertEqual(plus10(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 36 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 37 | def testSimpleAndRebinding(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 38 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 39 | def make_adder3(x): |
| 40 | def adder(y): |
| 41 | return x + y |
| 42 | x = x + 1 # check tracking of assignment to x in defining scope |
| 43 | return adder |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 44 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 45 | inc = make_adder3(0) |
| 46 | plus10 = make_adder3(9) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 47 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 48 | self.assertEqual(inc(1), 2) |
| 49 | self.assertEqual(plus10(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 50 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 51 | def testNestingGlobalNoFree(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 52 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 53 | def make_adder4(): # XXX add exta level of indirection |
| 54 | def nest(): |
| 55 | def nest(): |
| 56 | def adder(y): |
| 57 | return global_x + y # check that plain old globals work |
| 58 | return adder |
| 59 | return nest() |
| 60 | return nest() |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 61 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 62 | global_x = 1 |
| 63 | adder = make_adder4() |
| 64 | self.assertEqual(adder(1), 2) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 65 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 66 | global_x = 10 |
| 67 | self.assertEqual(adder(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 68 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 69 | def testNestingThroughClass(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 70 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 71 | def make_adder5(x): |
| 72 | class Adder: |
| 73 | def __call__(self, y): |
| 74 | return x + y |
| 75 | return Adder() |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 76 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 77 | inc = make_adder5(1) |
| 78 | plus10 = make_adder5(10) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 79 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 80 | self.assertEqual(inc(1), 2) |
| 81 | self.assertEqual(plus10(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 82 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 83 | def testNestingPlusFreeRefToGlobal(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 84 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 85 | def make_adder6(x): |
| 86 | global global_nest_x |
| 87 | def adder(y): |
| 88 | return global_nest_x + y |
| 89 | global_nest_x = x |
| 90 | return adder |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 91 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 92 | inc = make_adder6(1) |
| 93 | plus10 = make_adder6(10) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 94 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 95 | self.assertEqual(inc(1), 11) # there's only one global |
| 96 | self.assertEqual(plus10(-2), 8) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 97 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 98 | def testNearestEnclosingScope(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 99 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 100 | def f(x): |
| 101 | def g(y): |
| 102 | x = 42 # check that this masks binding in f() |
| 103 | def h(z): |
| 104 | return x + z |
| 105 | return h |
| 106 | return g(2) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 107 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 108 | test_func = f(10) |
| 109 | self.assertEqual(test_func(5), 47) |
| 110 | |
| 111 | def testMixedFreevarsAndCellvars(self): |
| 112 | |
| 113 | def identity(x): |
| 114 | return x |
| 115 | |
| 116 | def f(x, y, z): |
| 117 | def g(a, b, c): |
| 118 | a = a + x # 3 |
| 119 | def h(): |
| 120 | # z * (4 + 9) |
| 121 | # 3 * 13 |
| 122 | return identity(z * (b + y)) |
| 123 | y = c + z # 9 |
| 124 | return h |
| 125 | return g |
| 126 | |
| 127 | g = f(1, 2, 3) |
| 128 | h = g(2, 4, 6) |
| 129 | self.assertEqual(h(), 39) |
| 130 | |
| 131 | def testFreeVarInMethod(self): |
| 132 | |
| 133 | def test(): |
| 134 | method_and_var = "var" |
| 135 | class Test: |
| 136 | def method_and_var(self): |
| 137 | return "method" |
| 138 | def test(self): |
| 139 | return method_and_var |
| 140 | def actual_global(self): |
| 141 | return str("global") |
| 142 | def str(self): |
| 143 | return str(self) |
| 144 | return Test() |
| 145 | |
| 146 | t = test() |
| 147 | self.assertEqual(t.test(), "var") |
| 148 | self.assertEqual(t.method_and_var(), "method") |
| 149 | self.assertEqual(t.actual_global(), "global") |
| 150 | |
| 151 | method_and_var = "var" |
| 152 | class Test: |
| 153 | # this class is not nested, so the rules are different |
| 154 | def method_and_var(self): |
| 155 | return "method" |
| 156 | def test(self): |
| 157 | return method_and_var |
| 158 | def actual_global(self): |
| 159 | return str("global") |
| 160 | def str(self): |
| 161 | return str(self) |
| 162 | |
| 163 | t = Test() |
| 164 | self.assertEqual(t.test(), "var") |
| 165 | self.assertEqual(t.method_and_var(), "method") |
| 166 | self.assertEqual(t.actual_global(), "global") |
| 167 | |
Amaury Forgeot d'Arc | e670bd4 | 2007-11-24 00:29:24 +0000 | [diff] [blame] | 168 | def testCellIsKwonlyArg(self): |
| 169 | # Issue 1409: Initialisation of a cell value, |
| 170 | # when it comes from a keyword-only parameter |
| 171 | def foo(*, a=17): |
| 172 | def bar(): |
| 173 | return a + 5 |
| 174 | return bar() + 3 |
| 175 | |
| 176 | self.assertEqual(foo(a=42), 50) |
| 177 | self.assertEqual(foo(), 25) |
| 178 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 179 | def testRecursion(self): |
| 180 | |
| 181 | def f(x): |
| 182 | def fact(n): |
| 183 | if n == 0: |
| 184 | return 1 |
| 185 | else: |
| 186 | return n * fact(n - 1) |
| 187 | if x >= 0: |
| 188 | return fact(x) |
| 189 | else: |
Collin Winter | 3add4d7 | 2007-08-29 23:37:32 +0000 | [diff] [blame] | 190 | raise ValueError("x must be >= 0") |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 191 | |
| 192 | self.assertEqual(f(6), 720) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 193 | |
| 194 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 195 | def testUnoptimizedNamespaces(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 196 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 197 | check_syntax_error(self, """if 1: |
| 198 | def unoptimized_clash1(strip): |
| 199 | def f(s): |
| 200 | from sys import * |
| 201 | return getrefcount(s) # ambiguity: free or local |
| 202 | return f |
| 203 | """) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 204 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 205 | check_syntax_error(self, """if 1: |
| 206 | def unoptimized_clash2(): |
| 207 | from sys import * |
| 208 | def f(s): |
| 209 | return getrefcount(s) # ambiguity: global or local |
| 210 | return f |
| 211 | """) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 212 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 213 | check_syntax_error(self, """if 1: |
| 214 | def unoptimized_clash2(): |
| 215 | from sys import * |
| 216 | def g(): |
| 217 | def f(s): |
| 218 | return getrefcount(s) # ambiguity: global or local |
| 219 | return f |
| 220 | """) |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 221 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 222 | check_syntax_error(self, """if 1: |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 223 | def f(): |
| 224 | def g(): |
| 225 | from sys import * |
| 226 | return getrefcount # global or local? |
| 227 | """) |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 228 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 229 | def testLambdas(self): |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 230 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 231 | f1 = lambda x: lambda y: x + y |
| 232 | inc = f1(1) |
| 233 | plus10 = f1(10) |
| 234 | self.assertEqual(inc(1), 2) |
| 235 | self.assertEqual(plus10(5), 15) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 236 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 237 | f2 = lambda x: (lambda : lambda y: x + y)() |
| 238 | inc = f2(1) |
| 239 | plus10 = f2(10) |
| 240 | self.assertEqual(inc(1), 2) |
| 241 | self.assertEqual(plus10(5), 15) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 242 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 243 | f3 = lambda x: lambda y: global_x + y |
| 244 | global_x = 1 |
| 245 | inc = f3(None) |
| 246 | self.assertEqual(inc(2), 3) |
Jeremy Hylton | 4588c78 | 2001-01-25 20:11:23 +0000 | [diff] [blame] | 247 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 248 | f8 = lambda x, y, z: lambda a, b, c: lambda : z * (b + y) |
| 249 | g = f8(1, 2, 3) |
| 250 | h = g(2, 4, 6) |
| 251 | self.assertEqual(h(), 18) |
Jeremy Hylton | de60248 | 2001-02-05 17:35:20 +0000 | [diff] [blame] | 252 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 253 | def testUnboundLocal(self): |
Jeremy Hylton | de60248 | 2001-02-05 17:35:20 +0000 | [diff] [blame] | 254 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 255 | def errorInOuter(): |
Guido van Rossum | be19ed7 | 2007-02-09 05:37:30 +0000 | [diff] [blame] | 256 | print(y) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 257 | def inner(): |
| 258 | return y |
| 259 | y = 1 |
Jeremy Hylton | de60248 | 2001-02-05 17:35:20 +0000 | [diff] [blame] | 260 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 261 | def errorInInner(): |
| 262 | def inner(): |
| 263 | return y |
| 264 | inner() |
| 265 | y = 1 |
Jeremy Hylton | de60248 | 2001-02-05 17:35:20 +0000 | [diff] [blame] | 266 | |
Alexandre Vassalotti | 6f82818 | 2009-07-21 02:51:58 +0000 | [diff] [blame] | 267 | self.assertRaises(UnboundLocalError, errorInOuter) |
| 268 | self.assertRaises(NameError, errorInInner) |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 269 | |
Amaury Forgeot d'Arc | ba117ef | 2010-09-10 21:39:53 +0000 | [diff] [blame] | 270 | def testUnboundLocal_AfterDel(self): |
| 271 | # #4617: It is now legal to delete a cell variable. |
| 272 | # The following functions must obviously compile, |
| 273 | # and give the correct error when accessing the deleted name. |
| 274 | def errorInOuter(): |
| 275 | y = 1 |
| 276 | del y |
| 277 | print(y) |
| 278 | def inner(): |
| 279 | return y |
| 280 | |
| 281 | def errorInInner(): |
| 282 | def inner(): |
| 283 | return y |
| 284 | y = 1 |
| 285 | del y |
| 286 | inner() |
| 287 | |
| 288 | self.assertRaises(UnboundLocalError, errorInOuter) |
| 289 | self.assertRaises(NameError, errorInInner) |
| 290 | |
| 291 | def testUnboundLocal_AugAssign(self): |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 292 | # test for bug #1501934: incorrect LOAD/STORE_GLOBAL generation |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 293 | exec("""if 1: |
| 294 | global_x = 1 |
| 295 | def f(): |
| 296 | global_x += 1 |
| 297 | try: |
| 298 | f() |
| 299 | except UnboundLocalError: |
| 300 | pass |
| 301 | else: |
| 302 | fail('scope of global_x not correctly determined') |
| 303 | """, {'fail': self.fail}) |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 304 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 305 | def testComplexDefinitions(self): |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 306 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 307 | def makeReturner(*lst): |
| 308 | def returner(): |
| 309 | return lst |
| 310 | return returner |
Tim Peters | 0e6d213 | 2001-02-15 23:56:39 +0000 | [diff] [blame] | 311 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 312 | self.assertEqual(makeReturner(1,2,3)(), (1,2,3)) |
Tim Peters | 0e6d213 | 2001-02-15 23:56:39 +0000 | [diff] [blame] | 313 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 314 | def makeReturner2(**kwargs): |
| 315 | def returner(): |
| 316 | return kwargs |
| 317 | return returner |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 318 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 319 | self.assertEqual(makeReturner2(a=11)()['a'], 11) |
Jeremy Hylton | 97a0167 | 2001-02-09 22:56:46 +0000 | [diff] [blame] | 320 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 321 | def testScopeOfGlobalStmt(self): |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 322 | # Examples posted by Samuele Pedroni to python-dev on 3/1/2001 |
Guido van Rossum | 9aa643c | 2001-03-01 20:35:45 +0000 | [diff] [blame] | 323 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 324 | exec("""if 1: |
| 325 | # I |
| 326 | x = 7 |
| 327 | def f(): |
| 328 | x = 1 |
| 329 | def g(): |
| 330 | global x |
| 331 | def i(): |
| 332 | def h(): |
| 333 | return x |
| 334 | return h() |
| 335 | return i() |
| 336 | return g() |
| 337 | self.assertEqual(f(), 7) |
| 338 | self.assertEqual(x, 7) |
Guido van Rossum | 9aa643c | 2001-03-01 20:35:45 +0000 | [diff] [blame] | 339 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 340 | # II |
| 341 | x = 7 |
| 342 | def f(): |
| 343 | x = 1 |
| 344 | def g(): |
| 345 | x = 2 |
| 346 | def i(): |
| 347 | def h(): |
| 348 | return x |
| 349 | return h() |
| 350 | return i() |
| 351 | return g() |
| 352 | self.assertEqual(f(), 2) |
| 353 | self.assertEqual(x, 7) |
Guido van Rossum | 9aa643c | 2001-03-01 20:35:45 +0000 | [diff] [blame] | 354 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 355 | # III |
| 356 | x = 7 |
| 357 | def f(): |
| 358 | x = 1 |
| 359 | def g(): |
| 360 | global x |
| 361 | x = 2 |
| 362 | def i(): |
| 363 | def h(): |
| 364 | return x |
| 365 | return h() |
| 366 | return i() |
| 367 | return g() |
| 368 | self.assertEqual(f(), 2) |
| 369 | self.assertEqual(x, 2) |
Guido van Rossum | 9aa643c | 2001-03-01 20:35:45 +0000 | [diff] [blame] | 370 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 371 | # IV |
| 372 | x = 7 |
| 373 | def f(): |
| 374 | x = 3 |
| 375 | def g(): |
| 376 | global x |
| 377 | x = 2 |
| 378 | def i(): |
| 379 | def h(): |
| 380 | return x |
| 381 | return h() |
| 382 | return i() |
| 383 | return g() |
| 384 | self.assertEqual(f(), 2) |
| 385 | self.assertEqual(x, 2) |
Jeremy Hylton | 3e0055f | 2005-10-20 19:59:25 +0000 | [diff] [blame] | 386 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 387 | # XXX what about global statements in class blocks? |
| 388 | # do they affect methods? |
Jeremy Hylton | 3e0055f | 2005-10-20 19:59:25 +0000 | [diff] [blame] | 389 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 390 | x = 12 |
| 391 | class Global: |
| 392 | global x |
| 393 | x = 13 |
| 394 | def set(self, val): |
| 395 | x = val |
| 396 | def get(self): |
| 397 | return x |
Jeremy Hylton | 3e0055f | 2005-10-20 19:59:25 +0000 | [diff] [blame] | 398 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 399 | g = Global() |
| 400 | self.assertEqual(g.get(), 13) |
| 401 | g.set(15) |
| 402 | self.assertEqual(g.get(), 13) |
| 403 | """) |
Jeremy Hylton | 5b44a67 | 2001-03-13 02:01:12 +0000 | [diff] [blame] | 404 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 405 | def testLeaks(self): |
Jeremy Hylton | 5b44a67 | 2001-03-13 02:01:12 +0000 | [diff] [blame] | 406 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 407 | class Foo: |
| 408 | count = 0 |
Tim Peters | 30edd23 | 2001-03-16 08:29:48 +0000 | [diff] [blame] | 409 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 410 | def __init__(self): |
| 411 | Foo.count += 1 |
Jeremy Hylton | 5b44a67 | 2001-03-13 02:01:12 +0000 | [diff] [blame] | 412 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 413 | def __del__(self): |
| 414 | Foo.count -= 1 |
Jeremy Hylton | 5b44a67 | 2001-03-13 02:01:12 +0000 | [diff] [blame] | 415 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 416 | def f1(): |
| 417 | x = Foo() |
| 418 | def f2(): |
| 419 | return x |
| 420 | f2() |
Tim Peters | 30edd23 | 2001-03-16 08:29:48 +0000 | [diff] [blame] | 421 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 422 | for i in range(100): |
| 423 | f1() |
Jeremy Hylton | 5b44a67 | 2001-03-13 02:01:12 +0000 | [diff] [blame] | 424 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 425 | self.assertEqual(Foo.count, 0) |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 426 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 427 | def testClassAndGlobal(self): |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 428 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 429 | exec("""if 1: |
| 430 | def test(x): |
| 431 | class Foo: |
| 432 | global x |
| 433 | def __call__(self, y): |
| 434 | return x + y |
| 435 | return Foo() |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 436 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 437 | x = 0 |
| 438 | self.assertEqual(test(6)(2), 8) |
| 439 | x = -1 |
| 440 | self.assertEqual(test(3)(2), 5) |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 441 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 442 | looked_up_by_load_name = False |
| 443 | class X: |
| 444 | # Implicit globals inside classes are be looked up by LOAD_NAME, not |
| 445 | # LOAD_GLOBAL. |
| 446 | locals()['looked_up_by_load_name'] = True |
| 447 | passed = looked_up_by_load_name |
Neil Schemenauer | d403c45 | 2005-10-23 04:24:49 +0000 | [diff] [blame] | 448 | |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 449 | self.assertTrue(X.passed) |
| 450 | """) |
Neil Schemenauer | d403c45 | 2005-10-23 04:24:49 +0000 | [diff] [blame] | 451 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 452 | def testLocalsFunction(self): |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 453 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 454 | def f(x): |
| 455 | def g(y): |
| 456 | def h(z): |
| 457 | return y + z |
| 458 | w = x + y |
| 459 | y += 3 |
| 460 | return locals() |
| 461 | return g |
Jeremy Hylton | 5c7a251 | 2001-03-21 16:44:39 +0000 | [diff] [blame] | 462 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 463 | d = f(2)(4) |
Benjamin Peterson | 577473f | 2010-01-19 00:09:57 +0000 | [diff] [blame] | 464 | self.assertIn('h', d) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 465 | del d['h'] |
| 466 | self.assertEqual(d, {'x': 2, 'y': 7, 'w': 6}) |
Jeremy Hylton | c76770c | 2001-04-13 16:51:46 +0000 | [diff] [blame] | 467 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 468 | def testLocalsClass(self): |
| 469 | # This test verifies that calling locals() does not pollute |
| 470 | # the local namespace of the class with free variables. Old |
| 471 | # versions of Python had a bug, where a free variable being |
| 472 | # passed through a class namespace would be inserted into |
| 473 | # locals() by locals() or exec or a trace function. |
| 474 | # |
| 475 | # The real bug lies in frame code that copies variables |
| 476 | # between fast locals and the locals dict, e.g. when executing |
| 477 | # a trace function. |
| 478 | |
| 479 | def f(x): |
| 480 | class C: |
| 481 | x = 12 |
| 482 | def m(self): |
| 483 | return x |
| 484 | locals() |
| 485 | return C |
| 486 | |
| 487 | self.assertEqual(f(1).x, 12) |
| 488 | |
| 489 | def f(x): |
| 490 | class C: |
| 491 | y = x |
| 492 | def m(self): |
| 493 | return x |
| 494 | z = list(locals()) |
| 495 | return C |
| 496 | |
| 497 | varnames = f(1).z |
Benjamin Peterson | 577473f | 2010-01-19 00:09:57 +0000 | [diff] [blame] | 498 | self.assertNotIn("x", varnames) |
| 499 | self.assertIn("y", varnames) |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 500 | |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 501 | @cpython_only |
Georg Brandl | 3dbca81 | 2008-07-23 16:10:53 +0000 | [diff] [blame] | 502 | def testLocalsClass_WithTrace(self): |
| 503 | # Issue23728: after the trace function returns, the locals() |
| 504 | # dictionary is used to update all variables, this used to |
| 505 | # include free variables. But in class statements, free |
| 506 | # variables are not inserted... |
| 507 | import sys |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 508 | self.addCleanup(sys.settrace, sys.gettrace()) |
Georg Brandl | 3dbca81 | 2008-07-23 16:10:53 +0000 | [diff] [blame] | 509 | sys.settrace(lambda a,b,c:None) |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 510 | x = 12 |
Georg Brandl | 3dbca81 | 2008-07-23 16:10:53 +0000 | [diff] [blame] | 511 | |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 512 | class C: |
| 513 | def f(self): |
| 514 | return x |
Georg Brandl | 3dbca81 | 2008-07-23 16:10:53 +0000 | [diff] [blame] | 515 | |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 516 | self.assertEqual(x, 12) # Used to raise UnboundLocalError |
Georg Brandl | 3dbca81 | 2008-07-23 16:10:53 +0000 | [diff] [blame] | 517 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 518 | def testBoundAndFree(self): |
| 519 | # var is bound and free in class |
Jeremy Hylton | ddc4fd0 | 2001-04-27 02:29:40 +0000 | [diff] [blame] | 520 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 521 | def f(x): |
| 522 | class C: |
| 523 | def m(self): |
| 524 | return x |
| 525 | a = x |
| 526 | return C |
Jeremy Hylton | ddc4fd0 | 2001-04-27 02:29:40 +0000 | [diff] [blame] | 527 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 528 | inst = f(3)() |
| 529 | self.assertEqual(inst.a, inst.m()) |
Jeremy Hylton | 4c88901 | 2001-05-08 04:08:59 +0000 | [diff] [blame] | 530 | |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 531 | @cpython_only |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 532 | def testInteractionWithTraceFunc(self): |
Jeremy Hylton | 4c88901 | 2001-05-08 04:08:59 +0000 | [diff] [blame] | 533 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 534 | import sys |
| 535 | def tracer(a,b,c): |
| 536 | return tracer |
Jeremy Hylton | 4c88901 | 2001-05-08 04:08:59 +0000 | [diff] [blame] | 537 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 538 | def adaptgetter(name, klass, getter): |
| 539 | kind, des = getter |
| 540 | if kind == 1: # AV happens when stepping from this line to next |
| 541 | if des == "": |
| 542 | des = "_%s__%s" % (klass.__name__, name) |
| 543 | return lambda obj: getattr(obj, des) |
Jeremy Hylton | 4c88901 | 2001-05-08 04:08:59 +0000 | [diff] [blame] | 544 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 545 | class TestClass: |
| 546 | pass |
Jeremy Hylton | 4c88901 | 2001-05-08 04:08:59 +0000 | [diff] [blame] | 547 | |
Brett Cannon | 31f5929 | 2011-02-21 19:29:56 +0000 | [diff] [blame] | 548 | self.addCleanup(sys.settrace, sys.gettrace()) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 549 | sys.settrace(tracer) |
| 550 | adaptgetter("foo", TestClass, (1, "")) |
| 551 | sys.settrace(None) |
Jeremy Hylton | 5121e7d | 2001-07-30 21:55:29 +0000 | [diff] [blame] | 552 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 553 | self.assertRaises(TypeError, sys.settrace) |
Neal Norwitz | 290d31e | 2002-03-03 15:12:58 +0000 | [diff] [blame] | 554 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 555 | def testEvalExecFreeVars(self): |
Jeremy Hylton | 5121e7d | 2001-07-30 21:55:29 +0000 | [diff] [blame] | 556 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 557 | def f(x): |
| 558 | return lambda: x + 1 |
Jeremy Hylton | 5121e7d | 2001-07-30 21:55:29 +0000 | [diff] [blame] | 559 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 560 | g = f(3) |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 561 | self.assertRaises(TypeError, eval, g.__code__) |
Jeremy Hylton | cd73836 | 2001-08-07 16:38:19 +0000 | [diff] [blame] | 562 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 563 | try: |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 564 | exec(g.__code__, {}) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 565 | except TypeError: |
| 566 | pass |
| 567 | else: |
| 568 | self.fail("exec should have failed, because code contained free vars") |
Jeremy Hylton | ccae8377 | 2001-12-13 19:45:04 +0000 | [diff] [blame] | 569 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 570 | def testListCompLocalVars(self): |
Jeremy Hylton | cf672f1 | 2001-10-18 16:23:11 +0000 | [diff] [blame] | 571 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 572 | try: |
Guido van Rossum | be19ed7 | 2007-02-09 05:37:30 +0000 | [diff] [blame] | 573 | print(bad) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 574 | except NameError: |
| 575 | pass |
| 576 | else: |
Guido van Rossum | be19ed7 | 2007-02-09 05:37:30 +0000 | [diff] [blame] | 577 | print("bad should not be defined") |
Jeremy Hylton | cf672f1 | 2001-10-18 16:23:11 +0000 | [diff] [blame] | 578 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 579 | def x(): |
| 580 | [bad for s in 'a b' for bad in s.split()] |
Jeremy Hylton | cf672f1 | 2001-10-18 16:23:11 +0000 | [diff] [blame] | 581 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 582 | x() |
| 583 | try: |
Guido van Rossum | be19ed7 | 2007-02-09 05:37:30 +0000 | [diff] [blame] | 584 | print(bad) |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 585 | except NameError: |
| 586 | pass |
Jeremy Hylton | 954aed8 | 2002-04-20 04:51:39 +0000 | [diff] [blame] | 587 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 588 | def testEvalFreeVars(self): |
Jeremy Hylton | 954aed8 | 2002-04-20 04:51:39 +0000 | [diff] [blame] | 589 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 590 | def f(x): |
| 591 | def g(): |
| 592 | x |
| 593 | eval("x + 1") |
| 594 | return g |
Jeremy Hylton | 954aed8 | 2002-04-20 04:51:39 +0000 | [diff] [blame] | 595 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 596 | f(4)() |
| 597 | |
Christian Heimes | 18c6689 | 2008-02-17 13:31:39 +0000 | [diff] [blame] | 598 | def testFreeingCell(self): |
| 599 | # Test what happens when a finalizer accesses |
| 600 | # the cell where the object was stored. |
| 601 | class Special: |
| 602 | def __del__(self): |
| 603 | nestedcell_get() |
| 604 | |
Jeremy Hylton | 81e9502 | 2007-02-27 06:50:52 +0000 | [diff] [blame] | 605 | def testNonLocalFunction(self): |
| 606 | |
| 607 | def f(x): |
| 608 | def inc(): |
| 609 | nonlocal x |
| 610 | x += 1 |
| 611 | return x |
| 612 | def dec(): |
| 613 | nonlocal x |
| 614 | x -= 1 |
| 615 | return x |
| 616 | return inc, dec |
| 617 | |
| 618 | inc, dec = f(0) |
| 619 | self.assertEqual(inc(), 1) |
| 620 | self.assertEqual(inc(), 2) |
| 621 | self.assertEqual(dec(), 1) |
| 622 | self.assertEqual(dec(), 0) |
| 623 | |
| 624 | def testNonLocalMethod(self): |
Jeremy Hylton | 81e9502 | 2007-02-27 06:50:52 +0000 | [diff] [blame] | 625 | def f(x): |
| 626 | class c: |
| 627 | def inc(self): |
| 628 | nonlocal x |
| 629 | x += 1 |
| 630 | return x |
| 631 | def dec(self): |
| 632 | nonlocal x |
| 633 | x -= 1 |
| 634 | return x |
| 635 | return c() |
Jeremy Hylton | 81e9502 | 2007-02-27 06:50:52 +0000 | [diff] [blame] | 636 | c = f(0) |
| 637 | self.assertEqual(c.inc(), 1) |
| 638 | self.assertEqual(c.inc(), 2) |
| 639 | self.assertEqual(c.dec(), 1) |
| 640 | self.assertEqual(c.dec(), 0) |
| 641 | |
Jeremy Hylton | f37708e | 2009-03-31 15:26:37 +0000 | [diff] [blame] | 642 | def testGlobalInParallelNestedFunctions(self): |
| 643 | # A symbol table bug leaked the global statement from one |
| 644 | # function to other nested functions in the same block. |
| 645 | # This test verifies that a global statement in the first |
| 646 | # function does not affect the second function. |
Jeremy Hylton | f37708e | 2009-03-31 15:26:37 +0000 | [diff] [blame] | 647 | local_ns = {} |
| 648 | global_ns = {} |
Amaury Forgeot d'Arc | dfa9b29 | 2010-09-10 19:40:52 +0000 | [diff] [blame] | 649 | exec("""if 1: |
| 650 | def f(): |
| 651 | y = 1 |
| 652 | def g(): |
| 653 | global y |
| 654 | return y |
| 655 | def h(): |
| 656 | return y + 1 |
| 657 | return g, h |
| 658 | y = 9 |
| 659 | g, h = f() |
| 660 | result9 = g() |
| 661 | result2 = h() |
| 662 | """, local_ns, global_ns) |
Jeremy Hylton | f37708e | 2009-03-31 15:26:37 +0000 | [diff] [blame] | 663 | self.assertEqual(2, global_ns["result2"]) |
| 664 | self.assertEqual(9, global_ns["result9"]) |
| 665 | |
Jeremy Hylton | 81e9502 | 2007-02-27 06:50:52 +0000 | [diff] [blame] | 666 | def testNonLocalClass(self): |
| 667 | |
| 668 | def f(x): |
| 669 | class c: |
| 670 | nonlocal x |
| 671 | x += 1 |
| 672 | def get(self): |
| 673 | return x |
| 674 | return c() |
| 675 | |
| 676 | c = f(0) |
| 677 | self.assertEqual(c.get(), 1) |
Benjamin Peterson | 577473f | 2010-01-19 00:09:57 +0000 | [diff] [blame] | 678 | self.assertNotIn("x", c.__class__.__dict__) |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 679 | |
Jeremy Hylton | 81e9502 | 2007-02-27 06:50:52 +0000 | [diff] [blame] | 680 | |
| 681 | def testNonLocalGenerator(self): |
| 682 | |
| 683 | def f(x): |
| 684 | def g(y): |
| 685 | nonlocal x |
| 686 | for i in range(y): |
| 687 | x += 1 |
| 688 | yield x |
| 689 | return g |
| 690 | |
| 691 | g = f(0) |
| 692 | self.assertEqual(list(g(5)), [1, 2, 3, 4, 5]) |
| 693 | |
| 694 | def testNestedNonLocal(self): |
| 695 | |
| 696 | def f(x): |
| 697 | def g(): |
| 698 | nonlocal x |
| 699 | x -= 2 |
| 700 | def h(): |
| 701 | nonlocal x |
| 702 | x += 4 |
| 703 | return x |
| 704 | return h |
| 705 | return g |
| 706 | |
| 707 | g = f(1) |
| 708 | h = g() |
| 709 | self.assertEqual(h(), 3) |
| 710 | |
Benjamin Peterson | 230b206 | 2010-10-16 03:45:45 +0000 | [diff] [blame] | 711 | def testTopIsNotSignificant(self): |
| 712 | # See #9997. |
| 713 | def top(a): |
| 714 | pass |
| 715 | def b(): |
| 716 | global a |
| 717 | |
Benjamin Peterson | 3b0431d | 2013-04-30 09:41:40 -0400 | [diff] [blame] | 718 | def testClassNamespaceOverridesClosure(self): |
| 719 | # See #17853. |
| 720 | x = 42 |
| 721 | class X: |
| 722 | locals()["x"] = 43 |
| 723 | y = x |
| 724 | self.assertEqual(X.y, 43) |
| 725 | class X: |
| 726 | locals()["x"] = 43 |
| 727 | del x |
| 728 | self.assertFalse(hasattr(X, "x")) |
| 729 | self.assertEqual(x, 42) |
| 730 | |
Guido van Rossum | 6832c81 | 2013-05-10 08:47:42 -0700 | [diff] [blame] | 731 | @cpython_only |
| 732 | def testCellLeak(self): |
| 733 | # Issue 17927. |
| 734 | # |
| 735 | # The issue was that if self was part of a cycle involving the |
| 736 | # frame of a method call, *and* the method contained a nested |
| 737 | # function referencing self, thereby forcing 'self' into a |
| 738 | # cell, setting self to None would not be enough to break the |
| 739 | # frame -- the frame had another reference to the instance, |
| 740 | # which could not be cleared by the code running in the frame |
| 741 | # (though it will be cleared when the frame is collected). |
| 742 | # Without the lambda, setting self to None is enough to break |
| 743 | # the cycle. |
Benjamin Peterson | 2943cdb | 2013-05-11 16:10:52 -0500 | [diff] [blame] | 744 | class Tester: |
Guido van Rossum | 6832c81 | 2013-05-10 08:47:42 -0700 | [diff] [blame] | 745 | def dig(self): |
| 746 | if 0: |
| 747 | lambda: self |
| 748 | try: |
| 749 | 1/0 |
| 750 | except Exception as exc: |
| 751 | self.exc = exc |
Guido van Rossum | 6832c81 | 2013-05-10 08:47:42 -0700 | [diff] [blame] | 752 | self = None # Break the cycle |
| 753 | tester = Tester() |
| 754 | tester.dig() |
Benjamin Peterson | 2943cdb | 2013-05-11 16:10:52 -0500 | [diff] [blame] | 755 | ref = weakref.ref(tester) |
Guido van Rossum | 6832c81 | 2013-05-10 08:47:42 -0700 | [diff] [blame] | 756 | del tester |
Benjamin Peterson | 2943cdb | 2013-05-11 16:10:52 -0500 | [diff] [blame] | 757 | self.assertIsNone(ref()) |
Guido van Rossum | 6832c81 | 2013-05-10 08:47:42 -0700 | [diff] [blame] | 758 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 759 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 760 | if __name__ == '__main__': |
Zachary Ware | 38c707e | 2015-04-13 15:00:43 -0500 | [diff] [blame] | 761 | unittest.main() |