pytest-bdd/src/pytest_bdd/utils.py

90 lines
2.5 KiB
Python

"""Various utility functions."""
from __future__ import annotations
import base64
import pickle
import re
from inspect import getframeinfo, signature
from sys import _getframe
from typing import TYPE_CHECKING, TypeVar, cast
if TYPE_CHECKING:
from typing import Any, Callable
from _pytest.config import Config
from _pytest.pytester import RunResult
T = TypeVar("T")
CONFIG_STACK: list[Config] = []
def get_required_args(func: Callable[..., Any]) -> list[str]:
"""Get a list of argument that are required for a function.
:param func: The function to inspect.
:return: A list of argument names.
"""
params = signature(func).parameters.values()
return [
param.name for param in params if param.kind == param.POSITIONAL_OR_KEYWORD and param.default is param.empty
]
def get_caller_module_locals(stacklevel: int = 1) -> dict[str, Any]:
"""Get the caller module locals dictionary.
We use sys._getframe instead of inspect.stack(0) because the latter is way slower, since it iterates over
all the frames in the stack.
"""
return _getframe(stacklevel + 1).f_locals
def get_caller_module_path(depth: int = 2) -> str:
"""Get the caller module path.
We use sys._getframe instead of inspect.stack(0) because the latter is way slower, since it iterates over
all the frames in the stack.
"""
frame = _getframe(depth)
return getframeinfo(frame, context=0).filename
_DUMP_START = "_pytest_bdd_>>>"
_DUMP_END = "<<<_pytest_bdd_"
def dump_obj(*objects: Any) -> None:
"""Dump objects to stdout so that they can be inspected by the test suite."""
for obj in objects:
dump = pickle.dumps(obj, protocol=pickle.HIGHEST_PROTOCOL)
encoded = base64.b64encode(dump).decode("ascii")
print(f"{_DUMP_START}{encoded}{_DUMP_END}")
def collect_dumped_objects(result: RunResult) -> list:
"""Parse all the objects dumped with `dump_object` from the result.
Note: You must run the result with output to stdout enabled.
For example, using ``pytester.runpytest("-s")``.
"""
stdout = str(result.stdout)
payloads = re.findall(rf"{_DUMP_START}(.*?){_DUMP_END}", stdout)
return [pickle.loads(base64.b64decode(payload)) for payload in payloads]
def setdefault(obj: object, name: str, default: T) -> T:
"""Just like dict.setdefault, but for objects."""
try:
return cast(T, getattr(obj, name))
except AttributeError:
setattr(obj, name, default)
return default
def identity(x: T) -> T:
"""Return the argument."""
return x