"""
This module contains utilities that are mostly used
to make assertion comparison data report friendly.
"""
import re
from collections.abc import Mapping, Iterable
from testplan.common.utils.context import ContextValue
NATIVE_TYPES = (str, int, float, bool, memoryview, bytes, bytearray)
[docs]class AbsentType:
"""
A singleton to represent the lack of a value in a comparison.
None is not used to avoid the situation where a key may be
present and it's value is ``None``.
"""
__instance = None
descr = "ABSENT"
def __new__(cls):
if not isinstance(cls.__instance, cls):
cls.__instance = object.__new__(cls)
return cls.__instance
def __str__(self):
return self.descr
Absent = AbsentType()
[docs]def callable_name(callable_obj):
"""
Extract the name of a callable object
:param callable_obj: Callable object
:type callable_obj: Any object as long as it is callable
:return: Either the function name or the name of the class of the callable
:rtype: ``str``
"""
from .comparison import Callable
if isinstance(callable_obj, Callable):
return str(callable_obj)
doc = getattr(callable_obj, "__doc__", None)
if doc:
return doc.strip()
return (
getattr(callable_obj, "__name__", None)
or callable_obj.__class__.__name__
)
[docs]def fmt(obj):
"""
Recursively formats an object as plain old data.
:param obj: The object to format
:return: The plain old data representation
of "obj" that can be serialised to JSON
:rtype: ``object`` or a ``(object, object)`` pair
"""
def render(obj, key=None):
"""
Performs rendering to JSON dict
"""
obj_t = type(obj)
if obj is Absent:
ret = (0, None, str(obj))
elif obj is None:
ret = (0, None, None)
elif issubclass(obj_t, (int,)):
ret = (0, obj_t.__name__, str(obj))
elif issubclass(obj_t, NATIVE_TYPES):
ret = (0, obj_t.__name__, obj)
elif isinstance(obj, ContextValue):
ret = (0, "ContextValue", str(obj))
elif callable(obj):
ret = (0, "func", callable_name(obj))
elif issubclass(obj_t, Mapping):
ret = (
2,
[render(value, obj_key) for obj_key, value in obj.items()],
)
elif issubclass(obj_t, Iterable):
ret = (1, [render(value) for value in obj])
elif issubclass(obj_t, re.Pattern):
ret = (0, "REGEX", obj.pattern)
else:
ret = (0, obj_t.__name__, str(obj))
if key:
return key, ret
return ret
return render(obj)