Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 1 | import unittest |
Benjamin Peterson | ee8712c | 2008-05-20 21:35:26 +0000 | [diff] [blame] | 2 | from test import support |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 3 | |
| 4 | def funcattrs(**kwds): |
| 5 | def decorate(func): |
| 6 | func.__dict__.update(kwds) |
| 7 | return func |
| 8 | return decorate |
| 9 | |
| 10 | class MiscDecorators (object): |
| 11 | @staticmethod |
| 12 | def author(name): |
| 13 | def decorate(func): |
| 14 | func.__dict__['author'] = name |
| 15 | return func |
| 16 | return decorate |
| 17 | |
| 18 | # ----------------------------------------------- |
| 19 | |
| 20 | class DbcheckError (Exception): |
| 21 | def __init__(self, exprstr, func, args, kwds): |
| 22 | # A real version of this would set attributes here |
| 23 | Exception.__init__(self, "dbcheck %r failed (func=%s args=%s kwds=%s)" % |
| 24 | (exprstr, func, args, kwds)) |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 25 | |
| 26 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 27 | def dbcheck(exprstr, globals=None, locals=None): |
| 28 | "Decorator to implement debugging assertions" |
| 29 | def decorate(func): |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 30 | expr = compile(exprstr, "dbcheck-%s" % func.__name__, "eval") |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 31 | def check(*args, **kwds): |
| 32 | if not eval(expr, globals, locals): |
| 33 | raise DbcheckError(exprstr, func, args, kwds) |
| 34 | return func(*args, **kwds) |
| 35 | return check |
| 36 | return decorate |
| 37 | |
| 38 | # ----------------------------------------------- |
| 39 | |
| 40 | def countcalls(counts): |
| 41 | "Decorator to count calls to a function" |
| 42 | def decorate(func): |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 43 | func_name = func.__name__ |
Michael W. Hudson | 0ccff07 | 2004-08-17 17:29:16 +0000 | [diff] [blame] | 44 | counts[func_name] = 0 |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 45 | def call(*args, **kwds): |
Michael W. Hudson | 0ccff07 | 2004-08-17 17:29:16 +0000 | [diff] [blame] | 46 | counts[func_name] += 1 |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 47 | return func(*args, **kwds) |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 48 | call.__name__ = func_name |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 49 | return call |
| 50 | return decorate |
| 51 | |
| 52 | # ----------------------------------------------- |
| 53 | |
| 54 | def memoize(func): |
| 55 | saved = {} |
| 56 | def call(*args): |
| 57 | try: |
| 58 | return saved[args] |
| 59 | except KeyError: |
| 60 | res = func(*args) |
| 61 | saved[args] = res |
| 62 | return res |
| 63 | except TypeError: |
| 64 | # Unhashable argument |
| 65 | return func(*args) |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 66 | call.__name__ = func.__name__ |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 67 | return call |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 68 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 69 | # ----------------------------------------------- |
| 70 | |
| 71 | class TestDecorators(unittest.TestCase): |
| 72 | |
| 73 | def test_single(self): |
| 74 | class C(object): |
| 75 | @staticmethod |
| 76 | def foo(): return 42 |
| 77 | self.assertEqual(C.foo(), 42) |
| 78 | self.assertEqual(C().foo(), 42) |
| 79 | |
Anthony Baxter | 270fe88 | 2004-08-02 11:34:10 +0000 | [diff] [blame] | 80 | def test_staticmethod_function(self): |
| 81 | @staticmethod |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 82 | def notamethod(x): |
Anthony Baxter | 270fe88 | 2004-08-02 11:34:10 +0000 | [diff] [blame] | 83 | return x |
| 84 | self.assertRaises(TypeError, notamethod, 1) |
| 85 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 86 | def test_dotted(self): |
| 87 | decorators = MiscDecorators() |
| 88 | @decorators.author('Cleese') |
| 89 | def foo(): return 42 |
| 90 | self.assertEqual(foo(), 42) |
| 91 | self.assertEqual(foo.author, 'Cleese') |
| 92 | |
| 93 | def test_argforms(self): |
| 94 | # A few tests of argument passing, as we use restricted form |
| 95 | # of expressions for decorators. |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 96 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 97 | def noteargs(*args, **kwds): |
| 98 | def decorate(func): |
| 99 | setattr(func, 'dbval', (args, kwds)) |
| 100 | return func |
| 101 | return decorate |
| 102 | |
| 103 | args = ( 'Now', 'is', 'the', 'time' ) |
| 104 | kwds = dict(one=1, two=2) |
| 105 | @noteargs(*args, **kwds) |
| 106 | def f1(): return 42 |
| 107 | self.assertEqual(f1(), 42) |
| 108 | self.assertEqual(f1.dbval, (args, kwds)) |
| 109 | |
| 110 | @noteargs('terry', 'gilliam', eric='idle', john='cleese') |
| 111 | def f2(): return 84 |
| 112 | self.assertEqual(f2(), 84) |
| 113 | self.assertEqual(f2.dbval, (('terry', 'gilliam'), |
| 114 | dict(eric='idle', john='cleese'))) |
| 115 | |
| 116 | @noteargs(1, 2,) |
| 117 | def f3(): pass |
| 118 | self.assertEqual(f3.dbval, ((1, 2), {})) |
| 119 | |
| 120 | def test_dbcheck(self): |
| 121 | @dbcheck('args[1] is not None') |
| 122 | def f(a, b): |
| 123 | return a + b |
| 124 | self.assertEqual(f(1, 2), 3) |
| 125 | self.assertRaises(DbcheckError, f, 1, None) |
| 126 | |
| 127 | def test_memoize(self): |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 128 | counts = {} |
Michael W. Hudson | 0ccff07 | 2004-08-17 17:29:16 +0000 | [diff] [blame] | 129 | |
Brett Cannon | add3360 | 2004-08-15 07:21:25 +0000 | [diff] [blame] | 130 | @memoize |
| 131 | @countcalls(counts) |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 132 | def double(x): |
| 133 | return x * 2 |
Neal Norwitz | 221085d | 2007-02-25 20:55:47 +0000 | [diff] [blame] | 134 | self.assertEqual(double.__name__, 'double') |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 135 | |
| 136 | self.assertEqual(counts, dict(double=0)) |
| 137 | |
| 138 | # Only the first call with a given argument bumps the call count: |
| 139 | # |
| 140 | self.assertEqual(double(2), 4) |
| 141 | self.assertEqual(counts['double'], 1) |
| 142 | self.assertEqual(double(2), 4) |
| 143 | self.assertEqual(counts['double'], 1) |
| 144 | self.assertEqual(double(3), 6) |
| 145 | self.assertEqual(counts['double'], 2) |
| 146 | |
| 147 | # Unhashable arguments do not get memoized: |
| 148 | # |
| 149 | self.assertEqual(double([10]), [10, 10]) |
| 150 | self.assertEqual(counts['double'], 3) |
| 151 | self.assertEqual(double([10]), [10, 10]) |
| 152 | self.assertEqual(counts['double'], 4) |
| 153 | |
| 154 | def test_errors(self): |
| 155 | # Test syntax restrictions - these are all compile-time errors: |
| 156 | # |
| 157 | for expr in [ "1+2", "x[3]", "(1, 2)" ]: |
| 158 | # Sanity check: is expr is a valid expression by itself? |
| 159 | compile(expr, "testexpr", "exec") |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 160 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 161 | codestr = "@%s\ndef f(): pass" % expr |
| 162 | self.assertRaises(SyntaxError, compile, codestr, "test", "exec") |
| 163 | |
Michael W. Hudson | 0ccff07 | 2004-08-17 17:29:16 +0000 | [diff] [blame] | 164 | # You can't put multiple decorators on a single line: |
| 165 | # |
| 166 | self.assertRaises(SyntaxError, compile, |
| 167 | "@f1 @f2\ndef f(): pass", "test", "exec") |
| 168 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 169 | # Test runtime errors |
| 170 | |
| 171 | def unimp(func): |
| 172 | raise NotImplementedError |
| 173 | context = dict(nullval=None, unimp=unimp) |
Tim Peters | 6db15d7 | 2004-08-04 02:36:18 +0000 | [diff] [blame] | 174 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 175 | for expr, exc in [ ("undef", NameError), |
| 176 | ("nullval", TypeError), |
| 177 | ("nullval.attr", AttributeError), |
| 178 | ("unimp", NotImplementedError)]: |
| 179 | codestr = "@%s\ndef f(): pass\nassert f() is None" % expr |
| 180 | code = compile(codestr, "test", "exec") |
| 181 | self.assertRaises(exc, eval, code, context) |
| 182 | |
| 183 | def test_double(self): |
| 184 | class C(object): |
| 185 | @funcattrs(abc=1, xyz="haha") |
| 186 | @funcattrs(booh=42) |
| 187 | def foo(self): return 42 |
| 188 | self.assertEqual(C().foo(), 42) |
| 189 | self.assertEqual(C.foo.abc, 1) |
| 190 | self.assertEqual(C.foo.xyz, "haha") |
| 191 | self.assertEqual(C.foo.booh, 42) |
| 192 | |
| 193 | def test_order(self): |
Brett Cannon | caa9798 | 2004-08-19 03:48:24 +0000 | [diff] [blame] | 194 | # Test that decorators are applied in the proper order to the function |
| 195 | # they are decorating. |
| 196 | def callnum(num): |
| 197 | """Decorator factory that returns a decorator that replaces the |
| 198 | passed-in function with one that returns the value of 'num'""" |
| 199 | def deco(func): |
| 200 | return lambda: num |
| 201 | return deco |
| 202 | @callnum(2) |
| 203 | @callnum(1) |
| 204 | def foo(): return 42 |
| 205 | self.assertEqual(foo(), 2, |
| 206 | "Application order of decorators is incorrect") |
Brett Cannon | add3360 | 2004-08-15 07:21:25 +0000 | [diff] [blame] | 207 | |
Michael W. Hudson | 0ccff07 | 2004-08-17 17:29:16 +0000 | [diff] [blame] | 208 | def test_eval_order(self): |
| 209 | # Evaluating a decorated function involves four steps for each |
| 210 | # decorator-maker (the function that returns a decorator): |
| 211 | # |
| 212 | # 1: Evaluate the decorator-maker name |
| 213 | # 2: Evaluate the decorator-maker arguments (if any) |
| 214 | # 3: Call the decorator-maker to make a decorator |
| 215 | # 4: Call the decorator |
| 216 | # |
| 217 | # When there are multiple decorators, these steps should be |
| 218 | # performed in the above order for each decorator, but we should |
| 219 | # iterate through the decorators in the reverse of the order they |
| 220 | # appear in the source. |
| 221 | |
| 222 | actions = [] |
| 223 | |
| 224 | def make_decorator(tag): |
| 225 | actions.append('makedec' + tag) |
| 226 | def decorate(func): |
| 227 | actions.append('calldec' + tag) |
| 228 | return func |
| 229 | return decorate |
| 230 | |
| 231 | class NameLookupTracer (object): |
| 232 | def __init__(self, index): |
| 233 | self.index = index |
| 234 | |
| 235 | def __getattr__(self, fname): |
| 236 | if fname == 'make_decorator': |
| 237 | opname, res = ('evalname', make_decorator) |
| 238 | elif fname == 'arg': |
| 239 | opname, res = ('evalargs', str(self.index)) |
| 240 | else: |
| 241 | assert False, "Unknown attrname %s" % fname |
| 242 | actions.append('%s%d' % (opname, self.index)) |
| 243 | return res |
| 244 | |
| 245 | c1, c2, c3 = map(NameLookupTracer, [ 1, 2, 3 ]) |
| 246 | |
| 247 | expected_actions = [ 'evalname1', 'evalargs1', 'makedec1', |
| 248 | 'evalname2', 'evalargs2', 'makedec2', |
| 249 | 'evalname3', 'evalargs3', 'makedec3', |
| 250 | 'calldec3', 'calldec2', 'calldec1' ] |
| 251 | |
| 252 | actions = [] |
| 253 | @c1.make_decorator(c1.arg) |
| 254 | @c2.make_decorator(c2.arg) |
| 255 | @c3.make_decorator(c3.arg) |
| 256 | def foo(): return 42 |
| 257 | self.assertEqual(foo(), 42) |
| 258 | |
| 259 | self.assertEqual(actions, expected_actions) |
| 260 | |
| 261 | # Test the equivalence claim in chapter 7 of the reference manual. |
| 262 | # |
| 263 | actions = [] |
| 264 | def bar(): return 42 |
| 265 | bar = c1.make_decorator(c1.arg)(c2.make_decorator(c2.arg)(c3.make_decorator(c3.arg)(bar))) |
| 266 | self.assertEqual(bar(), 42) |
| 267 | self.assertEqual(actions, expected_actions) |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 268 | |
Guido van Rossum | d59da4b | 2007-05-22 18:11:13 +0000 | [diff] [blame] | 269 | class TestClassDecorators(unittest.TestCase): |
| 270 | |
| 271 | def test_simple(self): |
| 272 | def plain(x): |
| 273 | x.extra = 'Hello' |
| 274 | return x |
| 275 | @plain |
| 276 | class C(object): pass |
| 277 | self.assertEqual(C.extra, 'Hello') |
| 278 | |
| 279 | def test_double(self): |
| 280 | def ten(x): |
| 281 | x.extra = 10 |
| 282 | return x |
| 283 | def add_five(x): |
| 284 | x.extra += 5 |
| 285 | return x |
| 286 | |
| 287 | @add_five |
| 288 | @ten |
| 289 | class C(object): pass |
| 290 | self.assertEqual(C.extra, 15) |
| 291 | |
| 292 | def test_order(self): |
| 293 | def applied_first(x): |
| 294 | x.extra = 'first' |
| 295 | return x |
| 296 | def applied_second(x): |
| 297 | x.extra = 'second' |
| 298 | return x |
| 299 | @applied_second |
| 300 | @applied_first |
| 301 | class C(object): pass |
| 302 | self.assertEqual(C.extra, 'second') |
| 303 | |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 304 | def test_main(): |
Benjamin Peterson | ee8712c | 2008-05-20 21:35:26 +0000 | [diff] [blame] | 305 | support.run_unittest(TestDecorators) |
| 306 | support.run_unittest(TestClassDecorators) |
Anthony Baxter | c2a5a63 | 2004-08-02 06:10:11 +0000 | [diff] [blame] | 307 | |
| 308 | if __name__=="__main__": |
| 309 | test_main() |