/usr/lib/python3/dist-packages/_pytest/assertion/oldinterpret.py is in python3-pytest 2.8.7-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 | import traceback
import types
import py
import sys, inspect
from compiler import parse, ast, pycodegen
from _pytest.assertion.util import format_explanation, BuiltinAssertionError
passthroughex = py.builtin._sysex
class Failure:
def __init__(self, node):
self.exc, self.value, self.tb = sys.exc_info()
self.node = node
class View(object):
"""View base class.
If C is a subclass of View, then C(x) creates a proxy object around
the object x. The actual class of the proxy is not C in general,
but a *subclass* of C determined by the rules below. To avoid confusion
we call view class the class of the proxy (a subclass of C, so of View)
and object class the class of x.
Attributes and methods not found in the proxy are automatically read on x.
Other operations like setting attributes are performed on the proxy, as
determined by its view class. The object x is available from the proxy
as its __obj__ attribute.
The view class selection is determined by the __view__ tuples and the
optional __viewkey__ method. By default, the selected view class is the
most specific subclass of C whose __view__ mentions the class of x.
If no such subclass is found, the search proceeds with the parent
object classes. For example, C(True) will first look for a subclass
of C with __view__ = (..., bool, ...) and only if it doesn't find any
look for one with __view__ = (..., int, ...), and then ..., object,...
If everything fails the class C itself is considered to be the default.
Alternatively, the view class selection can be driven by another aspect
of the object x, instead of the class of x, by overriding __viewkey__.
See last example at the end of this module.
"""
_viewcache = {}
__view__ = ()
def __new__(rootclass, obj, *args, **kwds):
self = object.__new__(rootclass)
self.__obj__ = obj
self.__rootclass__ = rootclass
key = self.__viewkey__()
try:
self.__class__ = self._viewcache[key]
except KeyError:
self.__class__ = self._selectsubclass(key)
return self
def __getattr__(self, attr):
# attributes not found in the normal hierarchy rooted on View
# are looked up in the object's real class
return getattr(object.__getattribute__(self, '__obj__'), attr)
def __viewkey__(self):
return self.__obj__.__class__
def __matchkey__(self, key, subclasses):
if inspect.isclass(key):
keys = inspect.getmro(key)
else:
keys = [key]
for key in keys:
result = [C for C in subclasses if key in C.__view__]
if result:
return result
return []
def _selectsubclass(self, key):
subclasses = list(enumsubclasses(self.__rootclass__))
for C in subclasses:
if not isinstance(C.__view__, tuple):
C.__view__ = (C.__view__,)
choices = self.__matchkey__(key, subclasses)
if not choices:
return self.__rootclass__
elif len(choices) == 1:
return choices[0]
else:
# combine the multiple choices
return type('?', tuple(choices), {})
def __repr__(self):
return '%s(%r)' % (self.__rootclass__.__name__, self.__obj__)
def enumsubclasses(cls):
for subcls in cls.__subclasses__():
for subsubclass in enumsubclasses(subcls):
yield subsubclass
yield cls
class Interpretable(View):
"""A parse tree node with a few extra methods."""
explanation = None
def is_builtin(self, frame):
return False
def eval(self, frame):
# fall-back for unknown expression nodes
try:
expr = ast.Expression(self.__obj__)
expr.filename = '<eval>'
self.__obj__.filename = '<eval>'
co = pycodegen.ExpressionCodeGenerator(expr).getCode()
result = frame.eval(co)
except passthroughex:
raise
except:
raise Failure(self)
self.result = result
self.explanation = self.explanation or frame.repr(self.result)
def run(self, frame):
# fall-back for unknown statement nodes
try:
expr = ast.Module(None, ast.Stmt([self.__obj__]))
expr.filename = '<run>'
co = pycodegen.ModuleCodeGenerator(expr).getCode()
frame.exec_(co)
except passthroughex:
raise
except:
raise Failure(self)
def nice_explanation(self):
return format_explanation(self.explanation)
class Name(Interpretable):
__view__ = ast.Name
def is_local(self, frame):
source = '%r in locals() is not globals()' % self.name
try:
return frame.is_true(frame.eval(source))
except passthroughex:
raise
except:
return False
def is_global(self, frame):
source = '%r in globals()' % self.name
try:
return frame.is_true(frame.eval(source))
except passthroughex:
raise
except:
return False
def is_builtin(self, frame):
source = '%r not in locals() and %r not in globals()' % (
self.name, self.name)
try:
return frame.is_true(frame.eval(source))
except passthroughex:
raise
except:
return False
def eval(self, frame):
super(Name, self).eval(frame)
if not self.is_local(frame):
self.explanation = self.name
class Compare(Interpretable):
__view__ = ast.Compare
def eval(self, frame):
expr = Interpretable(self.expr)
expr.eval(frame)
for operation, expr2 in self.ops:
if hasattr(self, 'result'):
# shortcutting in chained expressions
if not frame.is_true(self.result):
break
expr2 = Interpretable(expr2)
expr2.eval(frame)
self.explanation = "%s %s %s" % (
expr.explanation, operation, expr2.explanation)
source = "__exprinfo_left %s __exprinfo_right" % operation
try:
self.result = frame.eval(source,
__exprinfo_left=expr.result,
__exprinfo_right=expr2.result)
except passthroughex:
raise
except:
raise Failure(self)
expr = expr2
class And(Interpretable):
__view__ = ast.And
def eval(self, frame):
explanations = []
for expr in self.nodes:
expr = Interpretable(expr)
expr.eval(frame)
explanations.append(expr.explanation)
self.result = expr.result
if not frame.is_true(expr.result):
break
self.explanation = '(' + ' and '.join(explanations) + ')'
class Or(Interpretable):
__view__ = ast.Or
def eval(self, frame):
explanations = []
for expr in self.nodes:
expr = Interpretable(expr)
expr.eval(frame)
explanations.append(expr.explanation)
self.result = expr.result
if frame.is_true(expr.result):
break
self.explanation = '(' + ' or '.join(explanations) + ')'
# == Unary operations ==
keepalive = []
for astclass, astpattern in {
ast.Not : 'not __exprinfo_expr',
ast.Invert : '(~__exprinfo_expr)',
}.items():
class UnaryArith(Interpretable):
__view__ = astclass
def eval(self, frame, astpattern=astpattern):
expr = Interpretable(self.expr)
expr.eval(frame)
self.explanation = astpattern.replace('__exprinfo_expr',
expr.explanation)
try:
self.result = frame.eval(astpattern,
__exprinfo_expr=expr.result)
except passthroughex:
raise
except:
raise Failure(self)
keepalive.append(UnaryArith)
# == Binary operations ==
for astclass, astpattern in {
ast.Add : '(__exprinfo_left + __exprinfo_right)',
ast.Sub : '(__exprinfo_left - __exprinfo_right)',
ast.Mul : '(__exprinfo_left * __exprinfo_right)',
ast.Div : '(__exprinfo_left / __exprinfo_right)',
ast.Mod : '(__exprinfo_left % __exprinfo_right)',
ast.Power : '(__exprinfo_left ** __exprinfo_right)',
}.items():
class BinaryArith(Interpretable):
__view__ = astclass
def eval(self, frame, astpattern=astpattern):
left = Interpretable(self.left)
left.eval(frame)
right = Interpretable(self.right)
right.eval(frame)
self.explanation = (astpattern
.replace('__exprinfo_left', left .explanation)
.replace('__exprinfo_right', right.explanation))
try:
self.result = frame.eval(astpattern,
__exprinfo_left=left.result,
__exprinfo_right=right.result)
except passthroughex:
raise
except:
raise Failure(self)
keepalive.append(BinaryArith)
class CallFunc(Interpretable):
__view__ = ast.CallFunc
def is_bool(self, frame):
source = 'isinstance(__exprinfo_value, bool)'
try:
return frame.is_true(frame.eval(source,
__exprinfo_value=self.result))
except passthroughex:
raise
except:
return False
def eval(self, frame):
node = Interpretable(self.node)
node.eval(frame)
explanations = []
vars = {'__exprinfo_fn': node.result}
source = '__exprinfo_fn('
for a in self.args:
if isinstance(a, ast.Keyword):
keyword = a.name
a = a.expr
else:
keyword = None
a = Interpretable(a)
a.eval(frame)
argname = '__exprinfo_%d' % len(vars)
vars[argname] = a.result
if keyword is None:
source += argname + ','
explanations.append(a.explanation)
else:
source += '%s=%s,' % (keyword, argname)
explanations.append('%s=%s' % (keyword, a.explanation))
if self.star_args:
star_args = Interpretable(self.star_args)
star_args.eval(frame)
argname = '__exprinfo_star'
vars[argname] = star_args.result
source += '*' + argname + ','
explanations.append('*' + star_args.explanation)
if self.dstar_args:
dstar_args = Interpretable(self.dstar_args)
dstar_args.eval(frame)
argname = '__exprinfo_kwds'
vars[argname] = dstar_args.result
source += '**' + argname + ','
explanations.append('**' + dstar_args.explanation)
self.explanation = "%s(%s)" % (
node.explanation, ', '.join(explanations))
if source.endswith(','):
source = source[:-1]
source += ')'
try:
self.result = frame.eval(source, **vars)
except passthroughex:
raise
except:
raise Failure(self)
if not node.is_builtin(frame) or not self.is_bool(frame):
r = frame.repr(self.result)
self.explanation = '%s\n{%s = %s\n}' % (r, r, self.explanation)
class Getattr(Interpretable):
__view__ = ast.Getattr
def eval(self, frame):
expr = Interpretable(self.expr)
expr.eval(frame)
source = '__exprinfo_expr.%s' % self.attrname
try:
try:
self.result = frame.eval(source, __exprinfo_expr=expr.result)
except AttributeError:
# Maybe the attribute name needs to be mangled?
if (not self.attrname.startswith("__") or
self.attrname.endswith("__")):
raise
source = "getattr(__exprinfo_expr.__class__, '__name__', '')"
class_name = frame.eval(source, __exprinfo_expr=expr.result)
mangled_attr = "_" + class_name + self.attrname
source = "__exprinfo_expr.%s" % (mangled_attr,)
self.result = frame.eval(source, __exprinfo_expr=expr.result)
except passthroughex:
raise
except:
raise Failure(self)
self.explanation = '%s.%s' % (expr.explanation, self.attrname)
# if the attribute comes from the instance, its value is interesting
source = ('hasattr(__exprinfo_expr, "__dict__") and '
'%r in __exprinfo_expr.__dict__' % self.attrname)
try:
from_instance = frame.is_true(
frame.eval(source, __exprinfo_expr=expr.result))
except passthroughex:
raise
except:
from_instance = True
if from_instance:
r = frame.repr(self.result)
self.explanation = '%s\n{%s = %s\n}' % (r, r, self.explanation)
# == Re-interpretation of full statements ==
class Assert(Interpretable):
__view__ = ast.Assert
def run(self, frame):
test = Interpretable(self.test)
test.eval(frame)
# print the result as 'assert <explanation>'
self.result = test.result
self.explanation = 'assert ' + test.explanation
if not frame.is_true(test.result):
try:
raise BuiltinAssertionError
except passthroughex:
raise
except:
raise Failure(self)
class Assign(Interpretable):
__view__ = ast.Assign
def run(self, frame):
expr = Interpretable(self.expr)
expr.eval(frame)
self.result = expr.result
self.explanation = '... = ' + expr.explanation
# fall-back-run the rest of the assignment
ass = ast.Assign(self.nodes, ast.Name('__exprinfo_expr'))
mod = ast.Module(None, ast.Stmt([ass]))
mod.filename = '<run>'
co = pycodegen.ModuleCodeGenerator(mod).getCode()
try:
frame.exec_(co, __exprinfo_expr=expr.result)
except passthroughex:
raise
except:
raise Failure(self)
class Discard(Interpretable):
__view__ = ast.Discard
def run(self, frame):
expr = Interpretable(self.expr)
expr.eval(frame)
self.result = expr.result
self.explanation = expr.explanation
class Stmt(Interpretable):
__view__ = ast.Stmt
def run(self, frame):
for stmt in self.nodes:
stmt = Interpretable(stmt)
stmt.run(frame)
def report_failure(e):
explanation = e.node.nice_explanation()
if explanation:
explanation = ", in: " + explanation
else:
explanation = ""
sys.stdout.write("%s: %s%s\n" % (e.exc.__name__, e.value, explanation))
def check(s, frame=None):
if frame is None:
frame = sys._getframe(1)
frame = py.code.Frame(frame)
expr = parse(s, 'eval')
assert isinstance(expr, ast.Expression)
node = Interpretable(expr.node)
try:
node.eval(frame)
except passthroughex:
raise
except Failure:
e = sys.exc_info()[1]
report_failure(e)
else:
if not frame.is_true(node.result):
sys.stderr.write("assertion failed: %s\n" % node.nice_explanation())
###########################################################
# API / Entry points
# #########################################################
def interpret(source, frame, should_fail=False):
module = Interpretable(parse(source, 'exec').node)
#print "got module", module
if isinstance(frame, types.FrameType):
frame = py.code.Frame(frame)
try:
module.run(frame)
except Failure:
e = sys.exc_info()[1]
return getfailure(e)
except passthroughex:
raise
except:
traceback.print_exc()
if should_fail:
return ("(assertion failed, but when it was re-run for "
"printing intermediate values, it did not fail. Suggestions: "
"compute assert expression before the assert or use --assert=plain)")
else:
return None
def getmsg(excinfo):
if isinstance(excinfo, tuple):
excinfo = py.code.ExceptionInfo(excinfo)
#frame, line = gettbline(tb)
#frame = py.code.Frame(frame)
#return interpret(line, frame)
tb = excinfo.traceback[-1]
source = str(tb.statement).strip()
x = interpret(source, tb.frame, should_fail=True)
if not isinstance(x, str):
raise TypeError("interpret returned non-string %r" % (x,))
return x
def getfailure(e):
explanation = e.node.nice_explanation()
if str(e.value):
lines = explanation.split('\n')
lines[0] += " << %s" % (e.value,)
explanation = '\n'.join(lines)
text = "%s: %s" % (e.exc.__name__, explanation)
if text.startswith('AssertionError: assert '):
text = text[16:]
return text
def run(s, frame=None):
if frame is None:
frame = sys._getframe(1)
frame = py.code.Frame(frame)
module = Interpretable(parse(s, 'exec').node)
try:
module.run(frame)
except Failure:
e = sys.exc_info()[1]
report_failure(e)
if __name__ == '__main__':
# example:
def f():
return 5
def g():
return 3
def h(x):
return 'never'
check("f() * g() == 5")
check("not f()")
check("not (f() and g() or 0)")
check("f() == g()")
i = 4
check("i == f()")
check("len(f()) == 0")
check("isinstance(2+3+4, float)")
run("x = i")
check("x == 5")
run("assert not f(), 'oops'")
run("a, b, c = 1, 2")
run("a, b, c = f()")
check("max([f(),g()]) == 4")
check("'hello'[g()] == 'h'")
run("'guk%d' % h(f())")
|