478 lines
16 KiB
Python
478 lines
16 KiB
Python
|
"""Utilities for assertion debugging."""
|
||
|
|
import collections.abc
|
||
|
|
import pprint
|
||
|
|
from typing import AbstractSet
|
||
|
|
from typing import Any
|
||
|
|
from typing import Callable
|
||
|
|
from typing import Iterable
|
||
|
|
from typing import List
|
||
|
|
from typing import Mapping
|
||
|
|
from typing import Optional
|
||
|
|
from typing import Sequence
|
||
|
|
|
||
|
|
import _pytest._code
|
||
|
|
from _pytest import outcomes
|
||
|
|
from _pytest._io.saferepr import _pformat_dispatch
|
||
|
|
from _pytest._io.saferepr import safeformat
|
||
|
|
from _pytest._io.saferepr import saferepr
|
||
|
|
|
||
|
|
# 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: Optional[Callable[[str, object, object], Optional[str]]] = None
|
||
|
|
|
||
|
|
# Works similarly as _reprcompare attribute. Is populated with the hook call
|
||
|
|
# when pytest_runtest_setup is called.
|
||
|
|
_assertion_pass: Optional[Callable[[int, str, str], None]] = None
|
||
|
|
|
||
|
|
|
||
|
|
def format_explanation(explanation: str) -> str:
|
||
|
|
r"""Format 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.
|
||
|
|
"""
|
||
|
|
lines = _split_explanation(explanation)
|
||
|
|
result = _format_lines(lines)
|
||
|
|
return "\n".join(result)
|
||
|
|
|
||
|
|
|
||
|
|
def _split_explanation(explanation: str) -> List[str]:
|
||
|
|
r"""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 "").split("\n")
|
||
|
|
lines = [raw_lines[0]]
|
||
|
|
for values in raw_lines[1:]:
|
||
|
|
if values and values[0] in ["{", "}", "~", ">"]:
|
||
|
|
lines.append(values)
|
||
|
|
else:
|
||
|
|
lines[-1] += "\\n" + values
|
||
|
|
return lines
|
||
|
|
|
||
|
|
|
||
|
|
def _format_lines(lines: Sequence[str]) -> List[str]:
|
||
|
|
"""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 = list(lines[:1])
|
||
|
|
stack = [0]
|
||
|
|
stackcnt = [0]
|
||
|
|
for line in lines[1:]:
|
||
|
|
if line.startswith("{"):
|
||
|
|
if stackcnt[-1]:
|
||
|
|
s = "and "
|
||
|
|
else:
|
||
|
|
s = "where "
|
||
|
|
stack.append(len(result))
|
||
|
|
stackcnt[-1] += 1
|
||
|
|
stackcnt.append(0)
|
||
|
|
result.append(" +" + " " * (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(" " * indent + line[1:])
|
||
|
|
assert len(stack) == 1
|
||
|
|
return result
|
||
|
|
|
||
|
|
|
||
|
|
def issequence(x: Any) -> bool:
|
||
|
|
return isinstance(x, collections.abc.Sequence) and not isinstance(x, str)
|
||
|
|
|
||
|
|
|
||
|
|
def istext(x: Any) -> bool:
|
||
|
|
return isinstance(x, str)
|
||
|
|
|
||
|
|
|
||
|
|
def isdict(x: Any) -> bool:
|
||
|
|
return isinstance(x, dict)
|
||
|
|
|
||
|
|
|
||
|
|
def isset(x: Any) -> bool:
|
||
|
|
return isinstance(x, (set, frozenset))
|
||
|
|
|
||
|
|
|
||
|
|
def isnamedtuple(obj: Any) -> bool:
|
||
|
|
return isinstance(obj, tuple) and getattr(obj, "_fields", None) is not None
|
||
|
|
|
||
|
|
|
||
|
|
def isdatacls(obj: Any) -> bool:
|
||
|
|
return getattr(obj, "__dataclass_fields__", None) is not None
|
||
|
|
|
||
|
|
|
||
|
|
def isattrs(obj: Any) -> bool:
|
||
|
|
return getattr(obj, "__attrs_attrs__", None) is not None
|
||
|
|
|
||
|
|
|
||
|
|
def isiterable(obj: Any) -> bool:
|
||
|
|
try:
|
||
|
|
iter(obj)
|
||
|
|
return not istext(obj)
|
||
|
|
except TypeError:
|
||
|
|
return False
|
||
|
|
|
||
|
|
|
||
|
|
def assertrepr_compare(config, op: str, left: Any, right: Any) -> Optional[List[str]]:
|
||
|
|
"""Return specialised explanations for some operators/operands."""
|
||
|
|
verbose = config.getoption("verbose")
|
||
|
|
if verbose > 1:
|
||
|
|
left_repr = safeformat(left)
|
||
|
|
right_repr = safeformat(right)
|
||
|
|
else:
|
||
|
|
# XXX: "15 chars indentation" is wrong
|
||
|
|
# ("E AssertionError: assert "); should use term width.
|
||
|
|
maxsize = (
|
||
|
|
80 - 15 - len(op) - 2
|
||
|
|
) // 2 # 15 chars indentation, 1 space around op
|
||
|
|
left_repr = saferepr(left, maxsize=maxsize)
|
||
|
|
right_repr = saferepr(right, maxsize=maxsize)
|
||
|
|
|
||
|
|
summary = f"{left_repr} {op} {right_repr}"
|
||
|
|
|
||
|
|
explanation = None
|
||
|
|
try:
|
||
|
|
if op == "==":
|
||
|
|
explanation = _compare_eq_any(left, right, verbose)
|
||
|
|
elif op == "not in":
|
||
|
|
if istext(left) and istext(right):
|
||
|
|
explanation = _notin_text(left, right, verbose)
|
||
|
|
except outcomes.Exit:
|
||
|
|
raise
|
||
|
|
except Exception:
|
||
|
|
explanation = [
|
||
|
|
"(pytest_assertion plugin: representation of details failed: {}.".format(
|
||
|
|
_pytest._code.ExceptionInfo.from_current()._getreprcrash()
|
||
|
|
),
|
||
|
|
" Probably an object has a faulty __repr__.)",
|
||
|
|
]
|
||
|
|
|
||
|
|
if not explanation:
|
||
|
|
return None
|
||
|
|
|
||
|
|
return [summary] + explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_any(left: Any, right: Any, verbose: int = 0) -> List[str]:
|
||
|
|
explanation = []
|
||
|
|
if istext(left) and istext(right):
|
||
|
|
explanation = _diff_text(left, right, verbose)
|
||
|
|
else:
|
||
|
|
if type(left) == type(right) and (
|
||
|
|
isdatacls(left) or isattrs(left) or isnamedtuple(left)
|
||
|
|
):
|
||
|
|
# Note: unlike dataclasses/attrs, namedtuples compare only the
|
||
|
|
# field values, not the type or field names. But this branch
|
||
|
|
# intentionally only handles the same-type case, which was often
|
||
|
|
# used in older code bases before dataclasses/attrs were available.
|
||
|
|
explanation = _compare_eq_cls(left, right, verbose)
|
||
|
|
elif 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)
|
||
|
|
elif verbose > 0:
|
||
|
|
explanation = _compare_eq_verbose(left, right)
|
||
|
|
if isiterable(left) and isiterable(right):
|
||
|
|
expl = _compare_eq_iterable(left, right, verbose)
|
||
|
|
explanation.extend(expl)
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _diff_text(left: str, right: str, verbose: int = 0) -> List[str]:
|
||
|
|
"""Return the explanation for the diff between text.
|
||
|
|
|
||
|
|
Unless --verbose is used this will skip leading and trailing
|
||
|
|
characters which are identical to keep the diff minimal.
|
||
|
|
"""
|
||
|
|
from difflib import ndiff
|
||
|
|
|
||
|
|
explanation: List[str] = []
|
||
|
|
|
||
|
|
if verbose < 1:
|
||
|
|
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 = [
|
||
|
|
"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 += [
|
||
|
|
"Skipping {} identical trailing "
|
||
|
|
"characters in diff, use -v to show".format(i)
|
||
|
|
]
|
||
|
|
left = left[:-i]
|
||
|
|
right = right[:-i]
|
||
|
|
keepends = True
|
||
|
|
if left.isspace() or right.isspace():
|
||
|
|
left = repr(str(left))
|
||
|
|
right = repr(str(right))
|
||
|
|
explanation += ["Strings contain only whitespace, escaping them using repr()"]
|
||
|
|
# "right" is the expected base against which we compare "left",
|
||
|
|
# see https://github.com/pytest-dev/pytest/issues/3333
|
||
|
|
explanation += [
|
||
|
|
line.strip("\n")
|
||
|
|
for line in ndiff(right.splitlines(keepends), left.splitlines(keepends))
|
||
|
|
]
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_verbose(left: Any, right: Any) -> List[str]:
|
||
|
|
keepends = True
|
||
|
|
left_lines = repr(left).splitlines(keepends)
|
||
|
|
right_lines = repr(right).splitlines(keepends)
|
||
|
|
|
||
|
|
explanation: List[str] = []
|
||
|
|
explanation += ["+" + line for line in left_lines]
|
||
|
|
explanation += ["-" + line for line in right_lines]
|
||
|
|
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _surrounding_parens_on_own_lines(lines: List[str]) -> None:
|
||
|
|
"""Move opening/closing parenthesis/bracket to own lines."""
|
||
|
|
opening = lines[0][:1]
|
||
|
|
if opening in ["(", "[", "{"]:
|
||
|
|
lines[0] = " " + lines[0][1:]
|
||
|
|
lines[:] = [opening] + lines
|
||
|
|
closing = lines[-1][-1:]
|
||
|
|
if closing in [")", "]", "}"]:
|
||
|
|
lines[-1] = lines[-1][:-1] + ","
|
||
|
|
lines[:] = lines + [closing]
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_iterable(
|
||
|
|
left: Iterable[Any], right: Iterable[Any], verbose: int = 0
|
||
|
|
) -> List[str]:
|
||
|
|
if not verbose:
|
||
|
|
return ["Use -v to get the full diff"]
|
||
|
|
# dynamic import to speedup pytest
|
||
|
|
import difflib
|
||
|
|
|
||
|
|
left_formatting = pprint.pformat(left).splitlines()
|
||
|
|
right_formatting = pprint.pformat(right).splitlines()
|
||
|
|
|
||
|
|
# Re-format for different output lengths.
|
||
|
|
lines_left = len(left_formatting)
|
||
|
|
lines_right = len(right_formatting)
|
||
|
|
if lines_left != lines_right:
|
||
|
|
left_formatting = _pformat_dispatch(left).splitlines()
|
||
|
|
right_formatting = _pformat_dispatch(right).splitlines()
|
||
|
|
|
||
|
|
if lines_left > 1 or lines_right > 1:
|
||
|
|
_surrounding_parens_on_own_lines(left_formatting)
|
||
|
|
_surrounding_parens_on_own_lines(right_formatting)
|
||
|
|
|
||
|
|
explanation = ["Full diff:"]
|
||
|
|
# "right" is the expected base against which we compare "left",
|
||
|
|
# see https://github.com/pytest-dev/pytest/issues/3333
|
||
|
|
explanation.extend(
|
||
|
|
line.rstrip() for line in difflib.ndiff(right_formatting, left_formatting)
|
||
|
|
)
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_sequence(
|
||
|
|
left: Sequence[Any], right: Sequence[Any], verbose: int = 0
|
||
|
|
) -> List[str]:
|
||
|
|
comparing_bytes = isinstance(left, bytes) and isinstance(right, bytes)
|
||
|
|
explanation: List[str] = []
|
||
|
|
len_left = len(left)
|
||
|
|
len_right = len(right)
|
||
|
|
for i in range(min(len_left, len_right)):
|
||
|
|
if left[i] != right[i]:
|
||
|
|
if comparing_bytes:
|
||
|
|
# when comparing bytes, we want to see their ascii representation
|
||
|
|
# instead of their numeric values (#5260)
|
||
|
|
# using a slice gives us the ascii representation:
|
||
|
|
# >>> s = b'foo'
|
||
|
|
# >>> s[0]
|
||
|
|
# 102
|
||
|
|
# >>> s[0:1]
|
||
|
|
# b'f'
|
||
|
|
left_value = left[i : i + 1]
|
||
|
|
right_value = right[i : i + 1]
|
||
|
|
else:
|
||
|
|
left_value = left[i]
|
||
|
|
right_value = right[i]
|
||
|
|
|
||
|
|
explanation += [f"At index {i} diff: {left_value!r} != {right_value!r}"]
|
||
|
|
break
|
||
|
|
|
||
|
|
if comparing_bytes:
|
||
|
|
# when comparing bytes, it doesn't help to show the "sides contain one or more
|
||
|
|
# items" longer explanation, so skip it
|
||
|
|
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
len_diff = len_left - len_right
|
||
|
|
if len_diff:
|
||
|
|
if len_diff > 0:
|
||
|
|
dir_with_more = "Left"
|
||
|
|
extra = saferepr(left[len_right])
|
||
|
|
else:
|
||
|
|
len_diff = 0 - len_diff
|
||
|
|
dir_with_more = "Right"
|
||
|
|
extra = saferepr(right[len_left])
|
||
|
|
|
||
|
|
if len_diff == 1:
|
||
|
|
explanation += [f"{dir_with_more} contains one more item: {extra}"]
|
||
|
|
else:
|
||
|
|
explanation += [
|
||
|
|
"%s contains %d more items, first extra item: %s"
|
||
|
|
% (dir_with_more, len_diff, extra)
|
||
|
|
]
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_set(
|
||
|
|
left: AbstractSet[Any], right: AbstractSet[Any], verbose: int = 0
|
||
|
|
) -> List[str]:
|
||
|
|
explanation = []
|
||
|
|
diff_left = left - right
|
||
|
|
diff_right = right - left
|
||
|
|
if diff_left:
|
||
|
|
explanation.append("Extra items in the left set:")
|
||
|
|
for item in diff_left:
|
||
|
|
explanation.append(saferepr(item))
|
||
|
|
if diff_right:
|
||
|
|
explanation.append("Extra items in the right set:")
|
||
|
|
for item in diff_right:
|
||
|
|
explanation.append(saferepr(item))
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_dict(
|
||
|
|
left: Mapping[Any, Any], right: Mapping[Any, Any], verbose: int = 0
|
||
|
|
) -> List[str]:
|
||
|
|
explanation: List[str] = []
|
||
|
|
set_left = set(left)
|
||
|
|
set_right = set(right)
|
||
|
|
common = set_left.intersection(set_right)
|
||
|
|
same = {k: left[k] for k in common if left[k] == right[k]}
|
||
|
|
if same and verbose < 2:
|
||
|
|
explanation += ["Omitting %s identical items, use -vv to show" % len(same)]
|
||
|
|
elif same:
|
||
|
|
explanation += ["Common items:"]
|
||
|
|
explanation += pprint.pformat(same).splitlines()
|
||
|
|
diff = {k for k in common if left[k] != right[k]}
|
||
|
|
if diff:
|
||
|
|
explanation += ["Differing items:"]
|
||
|
|
for k in diff:
|
||
|
|
explanation += [saferepr({k: left[k]}) + " != " + saferepr({k: right[k]})]
|
||
|
|
extra_left = set_left - set_right
|
||
|
|
len_extra_left = len(extra_left)
|
||
|
|
if len_extra_left:
|
||
|
|
explanation.append(
|
||
|
|
"Left contains %d more item%s:"
|
||
|
|
% (len_extra_left, "" if len_extra_left == 1 else "s")
|
||
|
|
)
|
||
|
|
explanation.extend(
|
||
|
|
pprint.pformat({k: left[k] for k in extra_left}).splitlines()
|
||
|
|
)
|
||
|
|
extra_right = set_right - set_left
|
||
|
|
len_extra_right = len(extra_right)
|
||
|
|
if len_extra_right:
|
||
|
|
explanation.append(
|
||
|
|
"Right contains %d more item%s:"
|
||
|
|
% (len_extra_right, "" if len_extra_right == 1 else "s")
|
||
|
|
)
|
||
|
|
explanation.extend(
|
||
|
|
pprint.pformat({k: right[k] for k in extra_right}).splitlines()
|
||
|
|
)
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _compare_eq_cls(left: Any, right: Any, verbose: int) -> List[str]:
|
||
|
|
if isdatacls(left):
|
||
|
|
all_fields = left.__dataclass_fields__
|
||
|
|
fields_to_check = [field for field, info in all_fields.items() if info.compare]
|
||
|
|
elif isattrs(left):
|
||
|
|
all_fields = left.__attrs_attrs__
|
||
|
|
fields_to_check = [field.name for field in all_fields if getattr(field, "eq")]
|
||
|
|
elif isnamedtuple(left):
|
||
|
|
fields_to_check = left._fields
|
||
|
|
else:
|
||
|
|
assert False
|
||
|
|
|
||
|
|
indent = " "
|
||
|
|
same = []
|
||
|
|
diff = []
|
||
|
|
for field in fields_to_check:
|
||
|
|
if getattr(left, field) == getattr(right, field):
|
||
|
|
same.append(field)
|
||
|
|
else:
|
||
|
|
diff.append(field)
|
||
|
|
|
||
|
|
explanation = []
|
||
|
|
if same or diff:
|
||
|
|
explanation += [""]
|
||
|
|
if same and verbose < 2:
|
||
|
|
explanation.append("Omitting %s identical items, use -vv to show" % len(same))
|
||
|
|
elif same:
|
||
|
|
explanation += ["Matching attributes:"]
|
||
|
|
explanation += pprint.pformat(same).splitlines()
|
||
|
|
if diff:
|
||
|
|
explanation += ["Differing attributes:"]
|
||
|
|
explanation += pprint.pformat(diff).splitlines()
|
||
|
|
for field in diff:
|
||
|
|
field_left = getattr(left, field)
|
||
|
|
field_right = getattr(right, field)
|
||
|
|
explanation += [
|
||
|
|
"",
|
||
|
|
"Drill down into differing attribute %s:" % field,
|
||
|
|
("%s%s: %r != %r") % (indent, field, field_left, field_right),
|
||
|
|
]
|
||
|
|
explanation += [
|
||
|
|
indent + line
|
||
|
|
for line in _compare_eq_any(field_left, field_right, verbose)
|
||
|
|
]
|
||
|
|
return explanation
|
||
|
|
|
||
|
|
|
||
|
|
def _notin_text(term: str, text: str, verbose: int = 0) -> List[str]:
|
||
|
|
index = text.find(term)
|
||
|
|
head = text[:index]
|
||
|
|
tail = text[index + len(term) :]
|
||
|
|
correct_text = head + tail
|
||
|
|
diff = _diff_text(text, correct_text, verbose)
|
||
|
|
newdiff = ["%s is contained here:" % saferepr(term, maxsize=42)]
|
||
|
|
for line in diff:
|
||
|
|
if line.startswith("Skipping"):
|
||
|
|
continue
|
||
|
|
if line.startswith("- "):
|
||
|
|
continue
|
||
|
|
if line.startswith("+ "):
|
||
|
|
newdiff.append(" " + line[2:])
|
||
|
|
else:
|
||
|
|
newdiff.append(line)
|
||
|
|
return newdiff
|