Update web-platform-tests and CSS tests.

- Update CSS tests to revision e05bfd5e30ed662c2f8a353577003f8eed230180.
- Update web-platform-tests to revision a052787dd5c069a340031011196b73affbd68cd9.
This commit is contained in:
Ms2ger 2017-02-06 11:06:12 +01:00
parent fb4f421c8b
commit 296fa2512b
21852 changed files with 2080936 additions and 892894 deletions

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"""
support for presenting detailed information in failing assertions.
"""
import py
import os
import sys
from _pytest.monkeypatch import monkeypatch
from _pytest.assertion import util
def pytest_addoption(parser):
group = parser.getgroup("debugconfig")
group.addoption('--assert',
action="store",
dest="assertmode",
choices=("rewrite", "reinterp", "plain",),
default="rewrite",
metavar="MODE",
help="""control assertion debugging tools. 'plain'
performs no assertion debugging. 'reinterp'
reinterprets assert statements after they failed
to provide assertion expression information.
'rewrite' (the default) rewrites assert
statements in test modules on import to
provide assert expression information. """)
group.addoption('--no-assert',
action="store_true",
default=False,
dest="noassert",
help="DEPRECATED equivalent to --assert=plain")
group.addoption('--nomagic', '--no-magic',
action="store_true",
default=False,
help="DEPRECATED equivalent to --assert=plain")
class AssertionState:
"""State for the assertion plugin."""
def __init__(self, config, mode):
self.mode = mode
self.trace = config.trace.root.get("assertion")
def pytest_configure(config):
mode = config.getvalue("assertmode")
if config.getvalue("noassert") or config.getvalue("nomagic"):
mode = "plain"
if mode == "rewrite":
try:
import ast # noqa
except ImportError:
mode = "reinterp"
else:
# Both Jython and CPython 2.6.0 have AST bugs that make the
# assertion rewriting hook malfunction.
if (sys.platform.startswith('java') or
sys.version_info[:3] == (2, 6, 0)):
mode = "reinterp"
if mode != "plain":
_load_modules(mode)
m = monkeypatch()
config._cleanup.append(m.undo)
m.setattr(py.builtin.builtins, 'AssertionError',
reinterpret.AssertionError) # noqa
hook = None
if mode == "rewrite":
hook = rewrite.AssertionRewritingHook() # noqa
sys.meta_path.insert(0, hook)
warn_about_missing_assertion(mode)
config._assertstate = AssertionState(config, mode)
config._assertstate.hook = hook
config._assertstate.trace("configured with mode set to %r" % (mode,))
def undo():
hook = config._assertstate.hook
if hook is not None and hook in sys.meta_path:
sys.meta_path.remove(hook)
config.add_cleanup(undo)
def pytest_collection(session):
# this hook is only called when test modules are collected
# so for example not in the master process of pytest-xdist
# (which does not collect test modules)
hook = session.config._assertstate.hook
if hook is not None:
hook.set_session(session)
def _running_on_ci():
"""Check if we're currently running on a CI system."""
env_vars = ['CI', 'BUILD_NUMBER']
return any(var in os.environ for var in env_vars)
def pytest_runtest_setup(item):
"""Setup the pytest_assertrepr_compare hook
The newinterpret and rewrite modules will use util._reprcompare if
it exists to use custom reporting via the
pytest_assertrepr_compare hook. This sets up this custom
comparison for the test.
"""
def callbinrepr(op, left, right):
"""Call the pytest_assertrepr_compare hook and prepare the result
This uses the first result from the hook and then ensures the
following:
* Overly verbose explanations are dropped unless -vv was used or
running on a CI.
* Embedded newlines are escaped to help util.format_explanation()
later.
* If the rewrite mode is used embedded %-characters are replaced
to protect later % formatting.
The result can be formatted by util.format_explanation() for
pretty printing.
"""
hook_result = item.ihook.pytest_assertrepr_compare(
config=item.config, op=op, left=left, right=right)
for new_expl in hook_result:
if new_expl:
if (sum(len(p) for p in new_expl[1:]) > 80*8 and
item.config.option.verbose < 2 and
not _running_on_ci()):
show_max = 10
truncated_lines = len(new_expl) - show_max
new_expl[show_max:] = [py.builtin._totext(
'Detailed information truncated (%d more lines)'
', use "-vv" to show' % truncated_lines)]
new_expl = [line.replace("\n", "\\n") for line in new_expl]
res = py.builtin._totext("\n~").join(new_expl)
if item.config.getvalue("assertmode") == "rewrite":
res = res.replace("%", "%%")
return res
util._reprcompare = callbinrepr
def pytest_runtest_teardown(item):
util._reprcompare = None
def pytest_sessionfinish(session):
hook = session.config._assertstate.hook
if hook is not None:
hook.session = None
def _load_modules(mode):
"""Lazily import assertion related code."""
global rewrite, reinterpret
from _pytest.assertion import reinterpret # noqa
if mode == "rewrite":
from _pytest.assertion import rewrite # noqa
def warn_about_missing_assertion(mode):
try:
assert False
except AssertionError:
pass
else:
if mode == "rewrite":
specifically = ("assertions which are not in test modules "
"will be ignored")
else:
specifically = "failing tests may report as passing"
sys.stderr.write("WARNING: " + specifically +
" because assert statements are not executed "
"by the underlying Python interpreter "
"(are you using python -O?)\n")
# Expose this plugin's implementation for the pytest_assertrepr_compare hook
pytest_assertrepr_compare = util.assertrepr_compare

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"""
Find intermediate evalutation results in assert statements through builtin AST.
"""
import ast
import sys
import _pytest._code
import py
from _pytest.assertion import util
u = py.builtin._totext
class AssertionError(util.BuiltinAssertionError):
def __init__(self, *args):
util.BuiltinAssertionError.__init__(self, *args)
if args:
# on Python2.6 we get len(args)==2 for: assert 0, (x,y)
# on Python2.7 and above we always get len(args) == 1
# with args[0] being the (x,y) tuple.
if len(args) > 1:
toprint = args
else:
toprint = args[0]
try:
self.msg = u(toprint)
except Exception:
self.msg = u(
"<[broken __repr__] %s at %0xd>"
% (toprint.__class__, id(toprint)))
else:
f = _pytest._code.Frame(sys._getframe(1))
try:
source = f.code.fullsource
if source is not None:
try:
source = source.getstatement(f.lineno, assertion=True)
except IndexError:
source = None
else:
source = str(source.deindent()).strip()
except py.error.ENOENT:
source = None
# this can also occur during reinterpretation, when the
# co_filename is set to "<run>".
if source:
self.msg = reinterpret(source, f, should_fail=True)
else:
self.msg = "<could not determine information>"
if not self.args:
self.args = (self.msg,)
if sys.version_info > (3, 0):
AssertionError.__module__ = "builtins"
if sys.platform.startswith("java"):
# See http://bugs.jython.org/issue1497
_exprs = ("BoolOp", "BinOp", "UnaryOp", "Lambda", "IfExp", "Dict",
"ListComp", "GeneratorExp", "Yield", "Compare", "Call",
"Repr", "Num", "Str", "Attribute", "Subscript", "Name",
"List", "Tuple")
_stmts = ("FunctionDef", "ClassDef", "Return", "Delete", "Assign",
"AugAssign", "Print", "For", "While", "If", "With", "Raise",
"TryExcept", "TryFinally", "Assert", "Import", "ImportFrom",
"Exec", "Global", "Expr", "Pass", "Break", "Continue")
_expr_nodes = set(getattr(ast, name) for name in _exprs)
_stmt_nodes = set(getattr(ast, name) for name in _stmts)
def _is_ast_expr(node):
return node.__class__ in _expr_nodes
def _is_ast_stmt(node):
return node.__class__ in _stmt_nodes
else:
def _is_ast_expr(node):
return isinstance(node, ast.expr)
def _is_ast_stmt(node):
return isinstance(node, ast.stmt)
try:
_Starred = ast.Starred
except AttributeError:
# Python 2. Define a dummy class so isinstance() will always be False.
class _Starred(object): pass
class Failure(Exception):
"""Error found while interpreting AST."""
def __init__(self, explanation=""):
self.cause = sys.exc_info()
self.explanation = explanation
def reinterpret(source, frame, should_fail=False):
mod = ast.parse(source)
visitor = DebugInterpreter(frame)
try:
visitor.visit(mod)
except Failure:
failure = sys.exc_info()[1]
return getfailure(failure)
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)")
def run(offending_line, frame=None):
if frame is None:
frame = _pytest._code.Frame(sys._getframe(1))
return reinterpret(offending_line, frame)
def getfailure(e):
explanation = util.format_explanation(e.explanation)
value = e.cause[1]
if str(value):
lines = explanation.split('\n')
lines[0] += " << %s" % (value,)
explanation = '\n'.join(lines)
text = "%s: %s" % (e.cause[0].__name__, explanation)
if text.startswith('AssertionError: assert '):
text = text[16:]
return text
operator_map = {
ast.BitOr : "|",
ast.BitXor : "^",
ast.BitAnd : "&",
ast.LShift : "<<",
ast.RShift : ">>",
ast.Add : "+",
ast.Sub : "-",
ast.Mult : "*",
ast.Div : "/",
ast.FloorDiv : "//",
ast.Mod : "%",
ast.Eq : "==",
ast.NotEq : "!=",
ast.Lt : "<",
ast.LtE : "<=",
ast.Gt : ">",
ast.GtE : ">=",
ast.Pow : "**",
ast.Is : "is",
ast.IsNot : "is not",
ast.In : "in",
ast.NotIn : "not in"
}
unary_map = {
ast.Not : "not %s",
ast.Invert : "~%s",
ast.USub : "-%s",
ast.UAdd : "+%s"
}
class DebugInterpreter(ast.NodeVisitor):
"""Interpret AST nodes to gleam useful debugging information. """
def __init__(self, frame):
self.frame = frame
def generic_visit(self, node):
# Fallback when we don't have a special implementation.
if _is_ast_expr(node):
mod = ast.Expression(node)
co = self._compile(mod)
try:
result = self.frame.eval(co)
except Exception:
raise Failure()
explanation = self.frame.repr(result)
return explanation, result
elif _is_ast_stmt(node):
mod = ast.Module([node])
co = self._compile(mod, "exec")
try:
self.frame.exec_(co)
except Exception:
raise Failure()
return None, None
else:
raise AssertionError("can't handle %s" %(node,))
def _compile(self, source, mode="eval"):
return compile(source, "<assertion interpretation>", mode)
def visit_Expr(self, expr):
return self.visit(expr.value)
def visit_Module(self, mod):
for stmt in mod.body:
self.visit(stmt)
def visit_Name(self, name):
explanation, result = self.generic_visit(name)
# See if the name is local.
source = "%r in locals() is not globals()" % (name.id,)
co = self._compile(source)
try:
local = self.frame.eval(co)
except Exception:
# have to assume it isn't
local = None
if local is None or not self.frame.is_true(local):
return name.id, result
return explanation, result
def visit_Compare(self, comp):
left = comp.left
left_explanation, left_result = self.visit(left)
for op, next_op in zip(comp.ops, comp.comparators):
next_explanation, next_result = self.visit(next_op)
op_symbol = operator_map[op.__class__]
explanation = "%s %s %s" % (left_explanation, op_symbol,
next_explanation)
source = "__exprinfo_left %s __exprinfo_right" % (op_symbol,)
co = self._compile(source)
try:
result = self.frame.eval(co, __exprinfo_left=left_result,
__exprinfo_right=next_result)
except Exception:
raise Failure(explanation)
try:
if not self.frame.is_true(result):
break
except KeyboardInterrupt:
raise
except:
break
left_explanation, left_result = next_explanation, next_result
if util._reprcompare is not None:
res = util._reprcompare(op_symbol, left_result, next_result)
if res:
explanation = res
return explanation, result
def visit_BoolOp(self, boolop):
is_or = isinstance(boolop.op, ast.Or)
explanations = []
for operand in boolop.values:
explanation, result = self.visit(operand)
explanations.append(explanation)
if result == is_or:
break
name = is_or and " or " or " and "
explanation = "(" + name.join(explanations) + ")"
return explanation, result
def visit_UnaryOp(self, unary):
pattern = unary_map[unary.op.__class__]
operand_explanation, operand_result = self.visit(unary.operand)
explanation = pattern % (operand_explanation,)
co = self._compile(pattern % ("__exprinfo_expr",))
try:
result = self.frame.eval(co, __exprinfo_expr=operand_result)
except Exception:
raise Failure(explanation)
return explanation, result
def visit_BinOp(self, binop):
left_explanation, left_result = self.visit(binop.left)
right_explanation, right_result = self.visit(binop.right)
symbol = operator_map[binop.op.__class__]
explanation = "(%s %s %s)" % (left_explanation, symbol,
right_explanation)
source = "__exprinfo_left %s __exprinfo_right" % (symbol,)
co = self._compile(source)
try:
result = self.frame.eval(co, __exprinfo_left=left_result,
__exprinfo_right=right_result)
except Exception:
raise Failure(explanation)
return explanation, result
def visit_Call(self, call):
func_explanation, func = self.visit(call.func)
arg_explanations = []
ns = {"__exprinfo_func" : func}
arguments = []
for arg in call.args:
arg_explanation, arg_result = self.visit(arg)
if isinstance(arg, _Starred):
arg_name = "__exprinfo_star"
ns[arg_name] = arg_result
arguments.append("*%s" % (arg_name,))
arg_explanations.append("*%s" % (arg_explanation,))
else:
arg_name = "__exprinfo_%s" % (len(ns),)
ns[arg_name] = arg_result
arguments.append(arg_name)
arg_explanations.append(arg_explanation)
for keyword in call.keywords:
arg_explanation, arg_result = self.visit(keyword.value)
if keyword.arg:
arg_name = "__exprinfo_%s" % (len(ns),)
keyword_source = "%s=%%s" % (keyword.arg)
arguments.append(keyword_source % (arg_name,))
arg_explanations.append(keyword_source % (arg_explanation,))
else:
arg_name = "__exprinfo_kwds"
arguments.append("**%s" % (arg_name,))
arg_explanations.append("**%s" % (arg_explanation,))
ns[arg_name] = arg_result
if getattr(call, 'starargs', None):
arg_explanation, arg_result = self.visit(call.starargs)
arg_name = "__exprinfo_star"
ns[arg_name] = arg_result
arguments.append("*%s" % (arg_name,))
arg_explanations.append("*%s" % (arg_explanation,))
if getattr(call, 'kwargs', None):
arg_explanation, arg_result = self.visit(call.kwargs)
arg_name = "__exprinfo_kwds"
ns[arg_name] = arg_result
arguments.append("**%s" % (arg_name,))
arg_explanations.append("**%s" % (arg_explanation,))
args_explained = ", ".join(arg_explanations)
explanation = "%s(%s)" % (func_explanation, args_explained)
args = ", ".join(arguments)
source = "__exprinfo_func(%s)" % (args,)
co = self._compile(source)
try:
result = self.frame.eval(co, **ns)
except Exception:
raise Failure(explanation)
pattern = "%s\n{%s = %s\n}"
rep = self.frame.repr(result)
explanation = pattern % (rep, rep, explanation)
return explanation, result
def _is_builtin_name(self, name):
pattern = "%r not in globals() and %r not in locals()"
source = pattern % (name.id, name.id)
co = self._compile(source)
try:
return self.frame.eval(co)
except Exception:
return False
def visit_Attribute(self, attr):
if not isinstance(attr.ctx, ast.Load):
return self.generic_visit(attr)
source_explanation, source_result = self.visit(attr.value)
explanation = "%s.%s" % (source_explanation, attr.attr)
source = "__exprinfo_expr.%s" % (attr.attr,)
co = self._compile(source)
try:
try:
result = self.frame.eval(co, __exprinfo_expr=source_result)
except AttributeError:
# Maybe the attribute name needs to be mangled?
if not attr.attr.startswith("__") or attr.attr.endswith("__"):
raise
source = "getattr(__exprinfo_expr.__class__, '__name__', '')"
co = self._compile(source)
class_name = self.frame.eval(co, __exprinfo_expr=source_result)
mangled_attr = "_" + class_name + attr.attr
source = "__exprinfo_expr.%s" % (mangled_attr,)
co = self._compile(source)
result = self.frame.eval(co, __exprinfo_expr=source_result)
except Exception:
raise Failure(explanation)
explanation = "%s\n{%s = %s.%s\n}" % (self.frame.repr(result),
self.frame.repr(result),
source_explanation, attr.attr)
# Check if the attr is from an instance.
source = "%r in getattr(__exprinfo_expr, '__dict__', {})"
source = source % (attr.attr,)
co = self._compile(source)
try:
from_instance = self.frame.eval(co, __exprinfo_expr=source_result)
except Exception:
from_instance = None
if from_instance is None or self.frame.is_true(from_instance):
rep = self.frame.repr(result)
pattern = "%s\n{%s = %s\n}"
explanation = pattern % (rep, rep, explanation)
return explanation, result
def visit_Assert(self, assrt):
test_explanation, test_result = self.visit(assrt.test)
explanation = "assert %s" % (test_explanation,)
if not self.frame.is_true(test_result):
try:
raise util.BuiltinAssertionError
except Exception:
raise Failure(explanation)
return explanation, test_result
def visit_Assign(self, assign):
value_explanation, value_result = self.visit(assign.value)
explanation = "... = %s" % (value_explanation,)
name = ast.Name("__exprinfo_expr", ast.Load(),
lineno=assign.value.lineno,
col_offset=assign.value.col_offset)
new_assign = ast.Assign(assign.targets, name, lineno=assign.lineno,
col_offset=assign.col_offset)
mod = ast.Module([new_assign])
co = self._compile(mod, "exec")
try:
self.frame.exec_(co, __exprinfo_expr=value_result)
except Exception:
raise Failure(explanation)
return explanation, value_result

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"""Rewrite assertion AST to produce nice error messages"""
import ast
import errno
import itertools
import imp
import marshal
import os
import re
import struct
import sys
import types
import py
from _pytest.assertion import util
# pytest caches rewritten pycs in __pycache__.
if hasattr(imp, "get_tag"):
PYTEST_TAG = imp.get_tag() + "-PYTEST"
else:
if hasattr(sys, "pypy_version_info"):
impl = "pypy"
elif sys.platform == "java":
impl = "jython"
else:
impl = "cpython"
ver = sys.version_info
PYTEST_TAG = "%s-%s%s-PYTEST" % (impl, ver[0], ver[1])
del ver, impl
PYC_EXT = ".py" + (__debug__ and "c" or "o")
PYC_TAIL = "." + PYTEST_TAG + PYC_EXT
REWRITE_NEWLINES = sys.version_info[:2] != (2, 7) and sys.version_info < (3, 2)
ASCII_IS_DEFAULT_ENCODING = sys.version_info[0] < 3
if sys.version_info >= (3,5):
ast_Call = ast.Call
else:
ast_Call = lambda a,b,c: ast.Call(a, b, c, None, None)
class AssertionRewritingHook(object):
"""PEP302 Import hook which rewrites asserts."""
def __init__(self):
self.session = None
self.modules = {}
self._register_with_pkg_resources()
def set_session(self, session):
self.fnpats = session.config.getini("python_files")
self.session = session
def find_module(self, name, path=None):
if self.session is None:
return None
sess = self.session
state = sess.config._assertstate
state.trace("find_module called for: %s" % name)
names = name.rsplit(".", 1)
lastname = names[-1]
pth = None
if path is not None:
# Starting with Python 3.3, path is a _NamespacePath(), which
# causes problems if not converted to list.
path = list(path)
if len(path) == 1:
pth = path[0]
if pth is None:
try:
fd, fn, desc = imp.find_module(lastname, path)
except ImportError:
return None
if fd is not None:
fd.close()
tp = desc[2]
if tp == imp.PY_COMPILED:
if hasattr(imp, "source_from_cache"):
fn = imp.source_from_cache(fn)
else:
fn = fn[:-1]
elif tp != imp.PY_SOURCE:
# Don't know what this is.
return None
else:
fn = os.path.join(pth, name.rpartition(".")[2] + ".py")
fn_pypath = py.path.local(fn)
# Is this a test file?
if not sess.isinitpath(fn):
# We have to be very careful here because imports in this code can
# trigger a cycle.
self.session = None
try:
for pat in self.fnpats:
if fn_pypath.fnmatch(pat):
state.trace("matched test file %r" % (fn,))
break
else:
return None
finally:
self.session = sess
else:
state.trace("matched test file (was specified on cmdline): %r" %
(fn,))
# The requested module looks like a test file, so rewrite it. This is
# the most magical part of the process: load the source, rewrite the
# asserts, and load the rewritten source. We also cache the rewritten
# module code in a special pyc. We must be aware of the possibility of
# concurrent pytest processes rewriting and loading pycs. To avoid
# tricky race conditions, we maintain the following invariant: The
# cached pyc is always a complete, valid pyc. Operations on it must be
# atomic. POSIX's atomic rename comes in handy.
write = not sys.dont_write_bytecode
cache_dir = os.path.join(fn_pypath.dirname, "__pycache__")
if write:
try:
os.mkdir(cache_dir)
except OSError:
e = sys.exc_info()[1].errno
if e == errno.EEXIST:
# Either the __pycache__ directory already exists (the
# common case) or it's blocked by a non-dir node. In the
# latter case, we'll ignore it in _write_pyc.
pass
elif e in [errno.ENOENT, errno.ENOTDIR]:
# One of the path components was not a directory, likely
# because we're in a zip file.
write = False
elif e in [errno.EACCES, errno.EROFS, errno.EPERM]:
state.trace("read only directory: %r" % fn_pypath.dirname)
write = False
else:
raise
cache_name = fn_pypath.basename[:-3] + PYC_TAIL
pyc = os.path.join(cache_dir, cache_name)
# Notice that even if we're in a read-only directory, I'm going
# to check for a cached pyc. This may not be optimal...
co = _read_pyc(fn_pypath, pyc, state.trace)
if co is None:
state.trace("rewriting %r" % (fn,))
source_stat, co = _rewrite_test(state, fn_pypath)
if co is None:
# Probably a SyntaxError in the test.
return None
if write:
_make_rewritten_pyc(state, source_stat, pyc, co)
else:
state.trace("found cached rewritten pyc for %r" % (fn,))
self.modules[name] = co, pyc
return self
def load_module(self, name):
# If there is an existing module object named 'fullname' in
# sys.modules, the loader must use that existing module. (Otherwise,
# the reload() builtin will not work correctly.)
if name in sys.modules:
return sys.modules[name]
co, pyc = self.modules.pop(name)
# I wish I could just call imp.load_compiled here, but __file__ has to
# be set properly. In Python 3.2+, this all would be handled correctly
# by load_compiled.
mod = sys.modules[name] = imp.new_module(name)
try:
mod.__file__ = co.co_filename
# Normally, this attribute is 3.2+.
mod.__cached__ = pyc
mod.__loader__ = self
py.builtin.exec_(co, mod.__dict__)
except:
del sys.modules[name]
raise
return sys.modules[name]
def is_package(self, name):
try:
fd, fn, desc = imp.find_module(name)
except ImportError:
return False
if fd is not None:
fd.close()
tp = desc[2]
return tp == imp.PKG_DIRECTORY
@classmethod
def _register_with_pkg_resources(cls):
"""
Ensure package resources can be loaded from this loader. May be called
multiple times, as the operation is idempotent.
"""
try:
import pkg_resources
# access an attribute in case a deferred importer is present
pkg_resources.__name__
except ImportError:
return
# Since pytest tests are always located in the file system, the
# DefaultProvider is appropriate.
pkg_resources.register_loader_type(cls, pkg_resources.DefaultProvider)
def get_data(self, pathname):
"""Optional PEP302 get_data API.
"""
with open(pathname, 'rb') as f:
return f.read()
def _write_pyc(state, co, source_stat, pyc):
# Technically, we don't have to have the same pyc format as
# (C)Python, since these "pycs" should never be seen by builtin
# import. However, there's little reason deviate, and I hope
# sometime to be able to use imp.load_compiled to load them. (See
# the comment in load_module above.)
try:
fp = open(pyc, "wb")
except IOError:
err = sys.exc_info()[1].errno
state.trace("error writing pyc file at %s: errno=%s" %(pyc, err))
# we ignore any failure to write the cache file
# there are many reasons, permission-denied, __pycache__ being a
# file etc.
return False
try:
fp.write(imp.get_magic())
mtime = int(source_stat.mtime)
size = source_stat.size & 0xFFFFFFFF
fp.write(struct.pack("<ll", mtime, size))
marshal.dump(co, fp)
finally:
fp.close()
return True
RN = "\r\n".encode("utf-8")
N = "\n".encode("utf-8")
cookie_re = re.compile(r"^[ \t\f]*#.*coding[:=][ \t]*[-\w.]+")
BOM_UTF8 = '\xef\xbb\xbf'
def _rewrite_test(state, fn):
"""Try to read and rewrite *fn* and return the code object."""
try:
stat = fn.stat()
source = fn.read("rb")
except EnvironmentError:
return None, None
if ASCII_IS_DEFAULT_ENCODING:
# ASCII is the default encoding in Python 2. Without a coding
# declaration, Python 2 will complain about any bytes in the file
# outside the ASCII range. Sadly, this behavior does not extend to
# compile() or ast.parse(), which prefer to interpret the bytes as
# latin-1. (At least they properly handle explicit coding cookies.) To
# preserve this error behavior, we could force ast.parse() to use ASCII
# as the encoding by inserting a coding cookie. Unfortunately, that
# messes up line numbers. Thus, we have to check ourselves if anything
# is outside the ASCII range in the case no encoding is explicitly
# declared. For more context, see issue #269. Yay for Python 3 which
# gets this right.
end1 = source.find("\n")
end2 = source.find("\n", end1 + 1)
if (not source.startswith(BOM_UTF8) and
cookie_re.match(source[0:end1]) is None and
cookie_re.match(source[end1 + 1:end2]) is None):
if hasattr(state, "_indecode"):
# encodings imported us again, so don't rewrite.
return None, None
state._indecode = True
try:
try:
source.decode("ascii")
except UnicodeDecodeError:
# Let it fail in real import.
return None, None
finally:
del state._indecode
# On Python versions which are not 2.7 and less than or equal to 3.1, the
# parser expects *nix newlines.
if REWRITE_NEWLINES:
source = source.replace(RN, N) + N
try:
tree = ast.parse(source)
except SyntaxError:
# Let this pop up again in the real import.
state.trace("failed to parse: %r" % (fn,))
return None, None
rewrite_asserts(tree)
try:
co = compile(tree, fn.strpath, "exec")
except SyntaxError:
# It's possible that this error is from some bug in the
# assertion rewriting, but I don't know of a fast way to tell.
state.trace("failed to compile: %r" % (fn,))
return None, None
return stat, co
def _make_rewritten_pyc(state, source_stat, pyc, co):
"""Try to dump rewritten code to *pyc*."""
if sys.platform.startswith("win"):
# Windows grants exclusive access to open files and doesn't have atomic
# rename, so just write into the final file.
_write_pyc(state, co, source_stat, pyc)
else:
# When not on windows, assume rename is atomic. Dump the code object
# into a file specific to this process and atomically replace it.
proc_pyc = pyc + "." + str(os.getpid())
if _write_pyc(state, co, source_stat, proc_pyc):
os.rename(proc_pyc, pyc)
def _read_pyc(source, pyc, trace=lambda x: None):
"""Possibly read a pytest pyc containing rewritten code.
Return rewritten code if successful or None if not.
"""
try:
fp = open(pyc, "rb")
except IOError:
return None
with fp:
try:
mtime = int(source.mtime())
size = source.size()
data = fp.read(12)
except EnvironmentError as e:
trace('_read_pyc(%s): EnvironmentError %s' % (source, e))
return None
# Check for invalid or out of date pyc file.
if (len(data) != 12 or data[:4] != imp.get_magic() or
struct.unpack("<ll", data[4:]) != (mtime, size)):
trace('_read_pyc(%s): invalid or out of date pyc' % source)
return None
try:
co = marshal.load(fp)
except Exception as e:
trace('_read_pyc(%s): marshal.load error %s' % (source, e))
return None
if not isinstance(co, types.CodeType):
trace('_read_pyc(%s): not a code object' % source)
return None
return co
def rewrite_asserts(mod):
"""Rewrite the assert statements in mod."""
AssertionRewriter().run(mod)
def _saferepr(obj):
"""Get a safe repr of an object for assertion error messages.
The assertion formatting (util.format_explanation()) requires
newlines to be escaped since they are a special character for it.
Normally assertion.util.format_explanation() does this but for a
custom repr it is possible to contain one of the special escape
sequences, especially '\n{' and '\n}' are likely to be present in
JSON reprs.
"""
repr = py.io.saferepr(obj)
if py.builtin._istext(repr):
t = py.builtin.text
else:
t = py.builtin.bytes
return repr.replace(t("\n"), t("\\n"))
from _pytest.assertion.util import format_explanation as _format_explanation # noqa
def _format_assertmsg(obj):
"""Format the custom assertion message given.
For strings this simply replaces newlines with '\n~' so that
util.format_explanation() will preserve them instead of escaping
newlines. For other objects py.io.saferepr() is used first.
"""
# reprlib appears to have a bug which means that if a string
# contains a newline it gets escaped, however if an object has a
# .__repr__() which contains newlines it does not get escaped.
# However in either case we want to preserve the newline.
if py.builtin._istext(obj) or py.builtin._isbytes(obj):
s = obj
is_repr = False
else:
s = py.io.saferepr(obj)
is_repr = True
if py.builtin._istext(s):
t = py.builtin.text
else:
t = py.builtin.bytes
s = s.replace(t("\n"), t("\n~")).replace(t("%"), t("%%"))
if is_repr:
s = s.replace(t("\\n"), t("\n~"))
return s
def _should_repr_global_name(obj):
return not hasattr(obj, "__name__") and not py.builtin.callable(obj)
def _format_boolop(explanations, is_or):
explanation = "(" + (is_or and " or " or " and ").join(explanations) + ")"
if py.builtin._istext(explanation):
t = py.builtin.text
else:
t = py.builtin.bytes
return explanation.replace(t('%'), t('%%'))
def _call_reprcompare(ops, results, expls, each_obj):
for i, res, expl in zip(range(len(ops)), results, expls):
try:
done = not res
except Exception:
done = True
if done:
break
if util._reprcompare is not None:
custom = util._reprcompare(ops[i], each_obj[i], each_obj[i + 1])
if custom is not None:
return custom
return expl
unary_map = {
ast.Not: "not %s",
ast.Invert: "~%s",
ast.USub: "-%s",
ast.UAdd: "+%s"
}
binop_map = {
ast.BitOr: "|",
ast.BitXor: "^",
ast.BitAnd: "&",
ast.LShift: "<<",
ast.RShift: ">>",
ast.Add: "+",
ast.Sub: "-",
ast.Mult: "*",
ast.Div: "/",
ast.FloorDiv: "//",
ast.Mod: "%%", # escaped for string formatting
ast.Eq: "==",
ast.NotEq: "!=",
ast.Lt: "<",
ast.LtE: "<=",
ast.Gt: ">",
ast.GtE: ">=",
ast.Pow: "**",
ast.Is: "is",
ast.IsNot: "is not",
ast.In: "in",
ast.NotIn: "not in"
}
# Python 3.5+ compatibility
try:
binop_map[ast.MatMult] = "@"
except AttributeError:
pass
# Python 3.4+ compatibility
if hasattr(ast, "NameConstant"):
_NameConstant = ast.NameConstant
else:
def _NameConstant(c):
return ast.Name(str(c), ast.Load())
def set_location(node, lineno, col_offset):
"""Set node location information recursively."""
def _fix(node, lineno, col_offset):
if "lineno" in node._attributes:
node.lineno = lineno
if "col_offset" in node._attributes:
node.col_offset = col_offset
for child in ast.iter_child_nodes(node):
_fix(child, lineno, col_offset)
_fix(node, lineno, col_offset)
return node
class AssertionRewriter(ast.NodeVisitor):
"""Assertion rewriting implementation.
The main entrypoint is to call .run() with an ast.Module instance,
this will then find all the assert statements and re-write them to
provide intermediate values and a detailed assertion error. See
http://pybites.blogspot.be/2011/07/behind-scenes-of-pytests-new-assertion.html
for an overview of how this works.
The entry point here is .run() which will iterate over all the
statements in an ast.Module and for each ast.Assert statement it
finds call .visit() with it. Then .visit_Assert() takes over and
is responsible for creating new ast statements to replace the
original assert statement: it re-writes the test of an assertion
to provide intermediate values and replace it with an if statement
which raises an assertion error with a detailed explanation in
case the expression is false.
For this .visit_Assert() uses the visitor pattern to visit all the
AST nodes of the ast.Assert.test field, each visit call returning
an AST node and the corresponding explanation string. During this
state is kept in several instance attributes:
:statements: All the AST statements which will replace the assert
statement.
:variables: This is populated by .variable() with each variable
used by the statements so that they can all be set to None at
the end of the statements.
:variable_counter: Counter to create new unique variables needed
by statements. Variables are created using .variable() and
have the form of "@py_assert0".
:on_failure: The AST statements which will be executed if the
assertion test fails. This is the code which will construct
the failure message and raises the AssertionError.
:explanation_specifiers: A dict filled by .explanation_param()
with %-formatting placeholders and their corresponding
expressions to use in the building of an assertion message.
This is used by .pop_format_context() to build a message.
:stack: A stack of the explanation_specifiers dicts maintained by
.push_format_context() and .pop_format_context() which allows
to build another %-formatted string while already building one.
This state is reset on every new assert statement visited and used
by the other visitors.
"""
def run(self, mod):
"""Find all assert statements in *mod* and rewrite them."""
if not mod.body:
# Nothing to do.
return
# Insert some special imports at the top of the module but after any
# docstrings and __future__ imports.
aliases = [ast.alias(py.builtin.builtins.__name__, "@py_builtins"),
ast.alias("_pytest.assertion.rewrite", "@pytest_ar")]
expect_docstring = True
pos = 0
lineno = 0
for item in mod.body:
if (expect_docstring and isinstance(item, ast.Expr) and
isinstance(item.value, ast.Str)):
doc = item.value.s
if "PYTEST_DONT_REWRITE" in doc:
# The module has disabled assertion rewriting.
return
lineno += len(doc) - 1
expect_docstring = False
elif (not isinstance(item, ast.ImportFrom) or item.level > 0 or
item.module != "__future__"):
lineno = item.lineno
break
pos += 1
imports = [ast.Import([alias], lineno=lineno, col_offset=0)
for alias in aliases]
mod.body[pos:pos] = imports
# Collect asserts.
nodes = [mod]
while nodes:
node = nodes.pop()
for name, field in ast.iter_fields(node):
if isinstance(field, list):
new = []
for i, child in enumerate(field):
if isinstance(child, ast.Assert):
# Transform assert.
new.extend(self.visit(child))
else:
new.append(child)
if isinstance(child, ast.AST):
nodes.append(child)
setattr(node, name, new)
elif (isinstance(field, ast.AST) and
# Don't recurse into expressions as they can't contain
# asserts.
not isinstance(field, ast.expr)):
nodes.append(field)
def variable(self):
"""Get a new variable."""
# Use a character invalid in python identifiers to avoid clashing.
name = "@py_assert" + str(next(self.variable_counter))
self.variables.append(name)
return name
def assign(self, expr):
"""Give *expr* a name."""
name = self.variable()
self.statements.append(ast.Assign([ast.Name(name, ast.Store())], expr))
return ast.Name(name, ast.Load())
def display(self, expr):
"""Call py.io.saferepr on the expression."""
return self.helper("saferepr", expr)
def helper(self, name, *args):
"""Call a helper in this module."""
py_name = ast.Name("@pytest_ar", ast.Load())
attr = ast.Attribute(py_name, "_" + name, ast.Load())
return ast_Call(attr, list(args), [])
def builtin(self, name):
"""Return the builtin called *name*."""
builtin_name = ast.Name("@py_builtins", ast.Load())
return ast.Attribute(builtin_name, name, ast.Load())
def explanation_param(self, expr):
"""Return a new named %-formatting placeholder for expr.
This creates a %-formatting placeholder for expr in the
current formatting context, e.g. ``%(py0)s``. The placeholder
and expr are placed in the current format context so that it
can be used on the next call to .pop_format_context().
"""
specifier = "py" + str(next(self.variable_counter))
self.explanation_specifiers[specifier] = expr
return "%(" + specifier + ")s"
def push_format_context(self):
"""Create a new formatting context.
The format context is used for when an explanation wants to
have a variable value formatted in the assertion message. In
this case the value required can be added using
.explanation_param(). Finally .pop_format_context() is used
to format a string of %-formatted values as added by
.explanation_param().
"""
self.explanation_specifiers = {}
self.stack.append(self.explanation_specifiers)
def pop_format_context(self, expl_expr):
"""Format the %-formatted string with current format context.
The expl_expr should be an ast.Str instance constructed from
the %-placeholders created by .explanation_param(). This will
add the required code to format said string to .on_failure and
return the ast.Name instance of the formatted string.
"""
current = self.stack.pop()
if self.stack:
self.explanation_specifiers = self.stack[-1]
keys = [ast.Str(key) for key in current.keys()]
format_dict = ast.Dict(keys, list(current.values()))
form = ast.BinOp(expl_expr, ast.Mod(), format_dict)
name = "@py_format" + str(next(self.variable_counter))
self.on_failure.append(ast.Assign([ast.Name(name, ast.Store())], form))
return ast.Name(name, ast.Load())
def generic_visit(self, node):
"""Handle expressions we don't have custom code for."""
assert isinstance(node, ast.expr)
res = self.assign(node)
return res, self.explanation_param(self.display(res))
def visit_Assert(self, assert_):
"""Return the AST statements to replace the ast.Assert instance.
This re-writes the test of an assertion to provide
intermediate values and replace it with an if statement which
raises an assertion error with a detailed explanation in case
the expression is false.
"""
self.statements = []
self.variables = []
self.variable_counter = itertools.count()
self.stack = []
self.on_failure = []
self.push_format_context()
# Rewrite assert into a bunch of statements.
top_condition, explanation = self.visit(assert_.test)
# Create failure message.
body = self.on_failure
negation = ast.UnaryOp(ast.Not(), top_condition)
self.statements.append(ast.If(negation, body, []))
if assert_.msg:
assertmsg = self.helper('format_assertmsg', assert_.msg)
explanation = "\n>assert " + explanation
else:
assertmsg = ast.Str("")
explanation = "assert " + explanation
template = ast.BinOp(assertmsg, ast.Add(), ast.Str(explanation))
msg = self.pop_format_context(template)
fmt = self.helper("format_explanation", msg)
err_name = ast.Name("AssertionError", ast.Load())
exc = ast_Call(err_name, [fmt], [])
if sys.version_info[0] >= 3:
raise_ = ast.Raise(exc, None)
else:
raise_ = ast.Raise(exc, None, None)
body.append(raise_)
# Clear temporary variables by setting them to None.
if self.variables:
variables = [ast.Name(name, ast.Store())
for name in self.variables]
clear = ast.Assign(variables, _NameConstant(None))
self.statements.append(clear)
# Fix line numbers.
for stmt in self.statements:
set_location(stmt, assert_.lineno, assert_.col_offset)
return self.statements
def visit_Name(self, name):
# Display the repr of the name if it's a local variable or
# _should_repr_global_name() thinks it's acceptable.
locs = ast_Call(self.builtin("locals"), [], [])
inlocs = ast.Compare(ast.Str(name.id), [ast.In()], [locs])
dorepr = self.helper("should_repr_global_name", name)
test = ast.BoolOp(ast.Or(), [inlocs, dorepr])
expr = ast.IfExp(test, self.display(name), ast.Str(name.id))
return name, self.explanation_param(expr)
def visit_BoolOp(self, boolop):
res_var = self.variable()
expl_list = self.assign(ast.List([], ast.Load()))
app = ast.Attribute(expl_list, "append", ast.Load())
is_or = int(isinstance(boolop.op, ast.Or))
body = save = self.statements
fail_save = self.on_failure
levels = len(boolop.values) - 1
self.push_format_context()
# Process each operand, short-circuting if needed.
for i, v in enumerate(boolop.values):
if i:
fail_inner = []
# cond is set in a prior loop iteration below
self.on_failure.append(ast.If(cond, fail_inner, [])) # noqa
self.on_failure = fail_inner
self.push_format_context()
res, expl = self.visit(v)
body.append(ast.Assign([ast.Name(res_var, ast.Store())], res))
expl_format = self.pop_format_context(ast.Str(expl))
call = ast_Call(app, [expl_format], [])
self.on_failure.append(ast.Expr(call))
if i < levels:
cond = res
if is_or:
cond = ast.UnaryOp(ast.Not(), cond)
inner = []
self.statements.append(ast.If(cond, inner, []))
self.statements = body = inner
self.statements = save
self.on_failure = fail_save
expl_template = self.helper("format_boolop", expl_list, ast.Num(is_or))
expl = self.pop_format_context(expl_template)
return ast.Name(res_var, ast.Load()), self.explanation_param(expl)
def visit_UnaryOp(self, unary):
pattern = unary_map[unary.op.__class__]
operand_res, operand_expl = self.visit(unary.operand)
res = self.assign(ast.UnaryOp(unary.op, operand_res))
return res, pattern % (operand_expl,)
def visit_BinOp(self, binop):
symbol = binop_map[binop.op.__class__]
left_expr, left_expl = self.visit(binop.left)
right_expr, right_expl = self.visit(binop.right)
explanation = "(%s %s %s)" % (left_expl, symbol, right_expl)
res = self.assign(ast.BinOp(left_expr, binop.op, right_expr))
return res, explanation
def visit_Call_35(self, call):
"""
visit `ast.Call` nodes on Python3.5 and after
"""
new_func, func_expl = self.visit(call.func)
arg_expls = []
new_args = []
new_kwargs = []
for arg in call.args:
res, expl = self.visit(arg)
arg_expls.append(expl)
new_args.append(res)
for keyword in call.keywords:
res, expl = self.visit(keyword.value)
new_kwargs.append(ast.keyword(keyword.arg, res))
if keyword.arg:
arg_expls.append(keyword.arg + "=" + expl)
else: ## **args have `arg` keywords with an .arg of None
arg_expls.append("**" + expl)
expl = "%s(%s)" % (func_expl, ', '.join(arg_expls))
new_call = ast.Call(new_func, new_args, new_kwargs)
res = self.assign(new_call)
res_expl = self.explanation_param(self.display(res))
outer_expl = "%s\n{%s = %s\n}" % (res_expl, res_expl, expl)
return res, outer_expl
def visit_Starred(self, starred):
# From Python 3.5, a Starred node can appear in a function call
res, expl = self.visit(starred.value)
return starred, '*' + expl
def visit_Call_legacy(self, call):
"""
visit `ast.Call nodes on 3.4 and below`
"""
new_func, func_expl = self.visit(call.func)
arg_expls = []
new_args = []
new_kwargs = []
new_star = new_kwarg = None
for arg in call.args:
res, expl = self.visit(arg)
new_args.append(res)
arg_expls.append(expl)
for keyword in call.keywords:
res, expl = self.visit(keyword.value)
new_kwargs.append(ast.keyword(keyword.arg, res))
arg_expls.append(keyword.arg + "=" + expl)
if call.starargs:
new_star, expl = self.visit(call.starargs)
arg_expls.append("*" + expl)
if call.kwargs:
new_kwarg, expl = self.visit(call.kwargs)
arg_expls.append("**" + expl)
expl = "%s(%s)" % (func_expl, ', '.join(arg_expls))
new_call = ast.Call(new_func, new_args, new_kwargs,
new_star, new_kwarg)
res = self.assign(new_call)
res_expl = self.explanation_param(self.display(res))
outer_expl = "%s\n{%s = %s\n}" % (res_expl, res_expl, expl)
return res, outer_expl
# ast.Call signature changed on 3.5,
# conditionally change which methods is named
# visit_Call depending on Python version
if sys.version_info >= (3, 5):
visit_Call = visit_Call_35
else:
visit_Call = visit_Call_legacy
def visit_Attribute(self, attr):
if not isinstance(attr.ctx, ast.Load):
return self.generic_visit(attr)
value, value_expl = self.visit(attr.value)
res = self.assign(ast.Attribute(value, attr.attr, ast.Load()))
res_expl = self.explanation_param(self.display(res))
pat = "%s\n{%s = %s.%s\n}"
expl = pat % (res_expl, res_expl, value_expl, attr.attr)
return res, expl
def visit_Compare(self, comp):
self.push_format_context()
left_res, left_expl = self.visit(comp.left)
res_variables = [self.variable() for i in range(len(comp.ops))]
load_names = [ast.Name(v, ast.Load()) for v in res_variables]
store_names = [ast.Name(v, ast.Store()) for v in res_variables]
it = zip(range(len(comp.ops)), comp.ops, comp.comparators)
expls = []
syms = []
results = [left_res]
for i, op, next_operand in it:
next_res, next_expl = self.visit(next_operand)
results.append(next_res)
sym = binop_map[op.__class__]
syms.append(ast.Str(sym))
expl = "%s %s %s" % (left_expl, sym, next_expl)
expls.append(ast.Str(expl))
res_expr = ast.Compare(left_res, [op], [next_res])
self.statements.append(ast.Assign([store_names[i]], res_expr))
left_res, left_expl = next_res, next_expl
# Use pytest.assertion.util._reprcompare if that's available.
expl_call = self.helper("call_reprcompare",
ast.Tuple(syms, ast.Load()),
ast.Tuple(load_names, ast.Load()),
ast.Tuple(expls, ast.Load()),
ast.Tuple(results, ast.Load()))
if len(comp.ops) > 1:
res = ast.BoolOp(ast.And(), load_names)
else:
res = load_names[0]
return res, self.explanation_param(self.pop_format_context(expl_call))

View file

@ -0,0 +1,332 @@
"""Utilities for assertion debugging"""
import pprint
import _pytest._code
import py
try:
from collections import Sequence
except ImportError:
Sequence = list
BuiltinAssertionError = py.builtin.builtins.AssertionError
u = py.builtin._totext
# The _reprcompare attribute on the util module is used by the new assertion
# interpretation code and assertion rewriter to detect this plugin was
# loaded and in turn call the hooks defined here as part of the
# DebugInterpreter.
_reprcompare = None
# the re-encoding is needed for python2 repr
# with non-ascii characters (see issue 877 and 1379)
def ecu(s):
try:
return u(s, 'utf-8', 'replace')
except TypeError:
return s
def format_explanation(explanation):
"""This formats an explanation
Normally all embedded newlines are escaped, however there are
three exceptions: \n{, \n} and \n~. The first two are intended
cover nested explanations, see function and attribute explanations
for examples (.visit_Call(), visit_Attribute()). The last one is
for when one explanation needs to span multiple lines, e.g. when
displaying diffs.
"""
explanation = ecu(explanation)
explanation = _collapse_false(explanation)
lines = _split_explanation(explanation)
result = _format_lines(lines)
return u('\n').join(result)
def _collapse_false(explanation):
"""Collapse expansions of False
So this strips out any "assert False\n{where False = ...\n}"
blocks.
"""
where = 0
while True:
start = where = explanation.find("False\n{False = ", where)
if where == -1:
break
level = 0
prev_c = explanation[start]
for i, c in enumerate(explanation[start:]):
if prev_c + c == "\n{":
level += 1
elif prev_c + c == "\n}":
level -= 1
if not level:
break
prev_c = c
else:
raise AssertionError("unbalanced braces: %r" % (explanation,))
end = start + i
where = end
if explanation[end - 1] == '\n':
explanation = (explanation[:start] + explanation[start+15:end-1] +
explanation[end+1:])
where -= 17
return explanation
def _split_explanation(explanation):
"""Return a list of individual lines in the explanation
This will return a list of lines split on '\n{', '\n}' and '\n~'.
Any other newlines will be escaped and appear in the line as the
literal '\n' characters.
"""
raw_lines = (explanation or u('')).split('\n')
lines = [raw_lines[0]]
for l in raw_lines[1:]:
if l and l[0] in ['{', '}', '~', '>']:
lines.append(l)
else:
lines[-1] += '\\n' + l
return lines
def _format_lines(lines):
"""Format the individual lines
This will replace the '{', '}' and '~' characters of our mini
formatting language with the proper 'where ...', 'and ...' and ' +
...' text, taking care of indentation along the way.
Return a list of formatted lines.
"""
result = lines[:1]
stack = [0]
stackcnt = [0]
for line in lines[1:]:
if line.startswith('{'):
if stackcnt[-1]:
s = u('and ')
else:
s = u('where ')
stack.append(len(result))
stackcnt[-1] += 1
stackcnt.append(0)
result.append(u(' +') + u(' ')*(len(stack)-1) + s + line[1:])
elif line.startswith('}'):
stack.pop()
stackcnt.pop()
result[stack[-1]] += line[1:]
else:
assert line[0] in ['~', '>']
stack[-1] += 1
indent = len(stack) if line.startswith('~') else len(stack) - 1
result.append(u(' ')*indent + line[1:])
assert len(stack) == 1
return result
# Provide basestring in python3
try:
basestring = basestring
except NameError:
basestring = str
def assertrepr_compare(config, op, left, right):
"""Return specialised explanations for some operators/operands"""
width = 80 - 15 - len(op) - 2 # 15 chars indentation, 1 space around op
left_repr = py.io.saferepr(left, maxsize=int(width/2))
right_repr = py.io.saferepr(right, maxsize=width-len(left_repr))
summary = u('%s %s %s') % (ecu(left_repr), op, ecu(right_repr))
issequence = lambda x: (isinstance(x, (list, tuple, Sequence)) and
not isinstance(x, basestring))
istext = lambda x: isinstance(x, basestring)
isdict = lambda x: isinstance(x, dict)
isset = lambda x: isinstance(x, (set, frozenset))
def isiterable(obj):
try:
iter(obj)
return not istext(obj)
except TypeError:
return False
verbose = config.getoption('verbose')
explanation = None
try:
if op == '==':
if istext(left) and istext(right):
explanation = _diff_text(left, right, verbose)
else:
if issequence(left) and issequence(right):
explanation = _compare_eq_sequence(left, right, verbose)
elif isset(left) and isset(right):
explanation = _compare_eq_set(left, right, verbose)
elif isdict(left) and isdict(right):
explanation = _compare_eq_dict(left, right, verbose)
if isiterable(left) and isiterable(right):
expl = _compare_eq_iterable(left, right, verbose)
if explanation is not None:
explanation.extend(expl)
else:
explanation = expl
elif op == 'not in':
if istext(left) and istext(right):
explanation = _notin_text(left, right, verbose)
except Exception:
explanation = [
u('(pytest_assertion plugin: representation of details failed. '
'Probably an object has a faulty __repr__.)'),
u(_pytest._code.ExceptionInfo())]
if not explanation:
return None
return [summary] + explanation
def _diff_text(left, right, verbose=False):
"""Return the explanation for the diff between text or bytes
Unless --verbose is used this will skip leading and trailing
characters which are identical to keep the diff minimal.
If the input are bytes they will be safely converted to text.
"""
from difflib import ndiff
explanation = []
if isinstance(left, py.builtin.bytes):
left = u(repr(left)[1:-1]).replace(r'\n', '\n')
if isinstance(right, py.builtin.bytes):
right = u(repr(right)[1:-1]).replace(r'\n', '\n')
if not verbose:
i = 0 # just in case left or right has zero length
for i in range(min(len(left), len(right))):
if left[i] != right[i]:
break
if i > 42:
i -= 10 # Provide some context
explanation = [u('Skipping %s identical leading '
'characters in diff, use -v to show') % i]
left = left[i:]
right = right[i:]
if len(left) == len(right):
for i in range(len(left)):
if left[-i] != right[-i]:
break
if i > 42:
i -= 10 # Provide some context
explanation += [u('Skipping %s identical trailing '
'characters in diff, use -v to show') % i]
left = left[:-i]
right = right[:-i]
explanation += [line.strip('\n')
for line in ndiff(left.splitlines(),
right.splitlines())]
return explanation
def _compare_eq_iterable(left, right, verbose=False):
if not verbose:
return [u('Use -v to get the full diff')]
# dynamic import to speedup pytest
import difflib
try:
left_formatting = pprint.pformat(left).splitlines()
right_formatting = pprint.pformat(right).splitlines()
explanation = [u('Full diff:')]
except Exception:
# hack: PrettyPrinter.pformat() in python 2 fails when formatting items that can't be sorted(), ie, calling
# sorted() on a list would raise. See issue #718.
# As a workaround, the full diff is generated by using the repr() string of each item of each container.
left_formatting = sorted(repr(x) for x in left)
right_formatting = sorted(repr(x) for x in right)
explanation = [u('Full diff (fallback to calling repr on each item):')]
explanation.extend(line.strip() for line in difflib.ndiff(left_formatting, right_formatting))
return explanation
def _compare_eq_sequence(left, right, verbose=False):
explanation = []
for i in range(min(len(left), len(right))):
if left[i] != right[i]:
explanation += [u('At index %s diff: %r != %r')
% (i, left[i], right[i])]
break
if len(left) > len(right):
explanation += [u('Left contains more items, first extra item: %s')
% py.io.saferepr(left[len(right)],)]
elif len(left) < len(right):
explanation += [
u('Right contains more items, first extra item: %s') %
py.io.saferepr(right[len(left)],)]
return explanation
def _compare_eq_set(left, right, verbose=False):
explanation = []
diff_left = left - right
diff_right = right - left
if diff_left:
explanation.append(u('Extra items in the left set:'))
for item in diff_left:
explanation.append(py.io.saferepr(item))
if diff_right:
explanation.append(u('Extra items in the right set:'))
for item in diff_right:
explanation.append(py.io.saferepr(item))
return explanation
def _compare_eq_dict(left, right, verbose=False):
explanation = []
common = set(left).intersection(set(right))
same = dict((k, left[k]) for k in common if left[k] == right[k])
if same and not verbose:
explanation += [u('Omitting %s identical items, use -v to show') %
len(same)]
elif same:
explanation += [u('Common items:')]
explanation += pprint.pformat(same).splitlines()
diff = set(k for k in common if left[k] != right[k])
if diff:
explanation += [u('Differing items:')]
for k in diff:
explanation += [py.io.saferepr({k: left[k]}) + ' != ' +
py.io.saferepr({k: right[k]})]
extra_left = set(left) - set(right)
if extra_left:
explanation.append(u('Left contains more items:'))
explanation.extend(pprint.pformat(
dict((k, left[k]) for k in extra_left)).splitlines())
extra_right = set(right) - set(left)
if extra_right:
explanation.append(u('Right contains more items:'))
explanation.extend(pprint.pformat(
dict((k, right[k]) for k in extra_right)).splitlines())
return explanation
def _notin_text(term, text, verbose=False):
index = text.find(term)
head = text[:index]
tail = text[index+len(term):]
correct_text = head + tail
diff = _diff_text(correct_text, text, verbose)
newdiff = [u('%s is contained here:') % py.io.saferepr(term, maxsize=42)]
for line in diff:
if line.startswith(u('Skipping')):
continue
if line.startswith(u('- ')):
continue
if line.startswith(u('+ ')):
newdiff.append(u(' ') + line[2:])
else:
newdiff.append(line)
return newdiff