pytest/src/_pytest/_io/pprint.py

676 lines
19 KiB
Python

# This module was imported from the cpython standard library
# (https://github.com/python/cpython/) at commit
# c5140945c723ae6c4b7ee81ff720ac8ea4b52cfd (python3.12).
#
#
# Original Author: Fred L. Drake, Jr.
# fdrake@acm.org
#
# This is a simple little module I wrote to make life easier. I didn't
# see anything quite like it in the library, though I may have overlooked
# something. I wrote this when I was trying to read some heavily nested
# tuples with fairly non-descriptive content. This is modeled very much
# after Lisp/Scheme - style pretty-printing of lists. If you find it
# useful, thank small children who sleep at night.
import collections as _collections
import dataclasses as _dataclasses
from io import StringIO as _StringIO
import re
import types as _types
from typing import Any
from typing import Callable
from typing import Dict
from typing import IO
from typing import Iterator
from typing import List
from typing import Optional
from typing import Set
from typing import Tuple
class _safe_key:
"""Helper function for key functions when sorting unorderable objects.
The wrapped-object will fallback to a Py2.x style comparison for
unorderable types (sorting first comparing the type name and then by
the obj ids). Does not work recursively, so dict.items() must have
_safe_key applied to both the key and the value.
"""
__slots__ = ["obj"]
def __init__(self, obj):
self.obj = obj
def __lt__(self, other):
try:
return self.obj < other.obj
except TypeError:
return (str(type(self.obj)), id(self.obj)) < (
str(type(other.obj)),
id(other.obj),
)
def _safe_tuple(t):
"""Helper function for comparing 2-tuples"""
return _safe_key(t[0]), _safe_key(t[1])
class PrettyPrinter:
def __init__(
self,
indent: int = 4,
width: int = 80,
depth: Optional[int] = None,
) -> None:
"""Handle pretty printing operations onto a stream using a set of
configured parameters.
indent
Number of spaces to indent for each level of nesting.
width
Attempted maximum number of columns in the output.
depth
The maximum depth to print out nested structures.
"""
if indent < 0:
raise ValueError("indent must be >= 0")
if depth is not None and depth <= 0:
raise ValueError("depth must be > 0")
if not width:
raise ValueError("width must be != 0")
self._depth = depth
self._indent_per_level = indent
self._width = width
def pformat(self, object: Any) -> str:
sio = _StringIO()
self._format(object, sio, 0, 0, set(), 0)
return sio.getvalue()
def _format(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
objid = id(object)
if objid in context:
stream.write(_recursion(object))
return
p = self._dispatch.get(type(object).__repr__, None)
if p is not None:
context.add(objid)
p(self, object, stream, indent, allowance, context, level + 1)
context.remove(objid)
elif (
_dataclasses.is_dataclass(object)
and not isinstance(object, type)
and object.__dataclass_params__.repr
and
# Check dataclass has generated repr method.
hasattr(object.__repr__, "__wrapped__")
and "__create_fn__" in object.__repr__.__wrapped__.__qualname__
):
context.add(objid)
self._pprint_dataclass(
object, stream, indent, allowance, context, level + 1
)
context.remove(objid)
else:
stream.write(self._repr(object, context, level))
def _pprint_dataclass(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
cls_name = object.__class__.__name__
items = [
(f.name, getattr(object, f.name))
for f in _dataclasses.fields(object)
if f.repr
]
stream.write(cls_name + "(")
self._format_namespace_items(items, stream, indent, allowance, context, level)
stream.write(")")
_dispatch: Dict[
Callable[..., str],
Callable[["PrettyPrinter", Any, IO[str], int, int, Set[int], int], None],
] = {}
def _pprint_dict(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
write = stream.write
write("{")
items = sorted(object.items(), key=_safe_tuple)
self._format_dict_items(items, stream, indent, allowance, context, level)
write("}")
_dispatch[dict.__repr__] = _pprint_dict
def _pprint_ordered_dict(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not len(object):
stream.write(repr(object))
return
cls = object.__class__
stream.write(cls.__name__ + "(")
self._pprint_dict(object, stream, indent, allowance, context, level)
stream.write(")")
_dispatch[_collections.OrderedDict.__repr__] = _pprint_ordered_dict
def _pprint_list(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
stream.write("[")
self._format_items(object, stream, indent, allowance, context, level)
stream.write("]")
_dispatch[list.__repr__] = _pprint_list
def _pprint_tuple(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
stream.write("(")
self._format_items(object, stream, indent, allowance, context, level)
stream.write(")")
_dispatch[tuple.__repr__] = _pprint_tuple
def _pprint_set(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not len(object):
stream.write(repr(object))
return
typ = object.__class__
if typ is set:
stream.write("{")
endchar = "}"
else:
stream.write(typ.__name__ + "({")
endchar = "})"
object = sorted(object, key=_safe_key)
self._format_items(object, stream, indent, allowance, context, level)
stream.write(endchar)
_dispatch[set.__repr__] = _pprint_set
_dispatch[frozenset.__repr__] = _pprint_set
def _pprint_str(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
write = stream.write
if not len(object):
write(repr(object))
return
chunks = []
lines = object.splitlines(True)
if level == 1:
indent += 1
allowance += 1
max_width1 = max_width = self._width - indent
for i, line in enumerate(lines):
rep = repr(line)
if i == len(lines) - 1:
max_width1 -= allowance
if len(rep) <= max_width1:
chunks.append(rep)
else:
# A list of alternating (non-space, space) strings
parts = re.findall(r"\S*\s*", line)
assert parts
assert not parts[-1]
parts.pop() # drop empty last part
max_width2 = max_width
current = ""
for j, part in enumerate(parts):
candidate = current + part
if j == len(parts) - 1 and i == len(lines) - 1:
max_width2 -= allowance
if len(repr(candidate)) > max_width2:
if current:
chunks.append(repr(current))
current = part
else:
current = candidate
if current:
chunks.append(repr(current))
if len(chunks) == 1:
write(rep)
return
if level == 1:
write("(")
for i, rep in enumerate(chunks):
if i > 0:
write("\n" + " " * indent)
write(rep)
if level == 1:
write(")")
_dispatch[str.__repr__] = _pprint_str
def _pprint_bytes(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
write = stream.write
if len(object) <= 4:
write(repr(object))
return
parens = level == 1
if parens:
indent += 1
allowance += 1
write("(")
delim = ""
for rep in _wrap_bytes_repr(object, self._width - indent, allowance):
write(delim)
write(rep)
if not delim:
delim = "\n" + " " * indent
if parens:
write(")")
_dispatch[bytes.__repr__] = _pprint_bytes
def _pprint_bytearray(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
write = stream.write
write("bytearray(")
self._pprint_bytes(
bytes(object), stream, indent + 10, allowance + 1, context, level + 1
)
write(")")
_dispatch[bytearray.__repr__] = _pprint_bytearray
def _pprint_mappingproxy(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
stream.write("mappingproxy(")
self._format(object.copy(), stream, indent, allowance, context, level)
stream.write(")")
_dispatch[_types.MappingProxyType.__repr__] = _pprint_mappingproxy
def _pprint_simplenamespace(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if type(object) is _types.SimpleNamespace:
# The SimpleNamespace repr is "namespace" instead of the class
# name, so we do the same here. For subclasses; use the class name.
cls_name = "namespace"
else:
cls_name = object.__class__.__name__
items = object.__dict__.items()
stream.write(cls_name + "(")
self._format_namespace_items(items, stream, indent, allowance, context, level)
stream.write(")")
_dispatch[_types.SimpleNamespace.__repr__] = _pprint_simplenamespace
def _format_dict_items(
self,
items: List[Tuple[Any, Any]],
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not items:
return
write = stream.write
item_indent = indent + self._indent_per_level
delimnl = "\n" + " " * item_indent
for key, ent in items:
write(delimnl)
write(self._repr(key, context, level))
write(": ")
self._format(ent, stream, item_indent, 1, context, level)
write(",")
write("\n" + " " * indent)
def _format_namespace_items(
self,
items: List[Tuple[Any, Any]],
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not items:
return
write = stream.write
item_indent = indent + self._indent_per_level
delimnl = "\n" + " " * item_indent
for key, ent in items:
write(delimnl)
write(key)
write("=")
if id(ent) in context:
# Special-case representation of recursion to match standard
# recursive dataclass repr.
write("...")
else:
self._format(
ent,
stream,
item_indent + len(key) + 1,
1,
context,
level,
)
write(",")
write("\n" + " " * indent)
def _format_items(
self,
items: List[Any],
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not items:
return
write = stream.write
item_indent = indent + self._indent_per_level
delimnl = "\n" + " " * item_indent
for item in items:
write(delimnl)
self._format(item, stream, item_indent, 1, context, level)
write(",")
write("\n" + " " * indent)
def _repr(self, object: Any, context: Set[int], level: int) -> str:
return self._safe_repr(object, context.copy(), self._depth, level)
def _pprint_default_dict(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
rdf = self._repr(object.default_factory, context, level)
stream.write(f"{object.__class__.__name__}({rdf}, ")
self._pprint_dict(object, stream, indent, allowance, context, level)
stream.write(")")
_dispatch[_collections.defaultdict.__repr__] = _pprint_default_dict
def _pprint_counter(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
stream.write(object.__class__.__name__ + "(")
if object:
stream.write("{")
items = object.most_common()
self._format_dict_items(items, stream, indent, allowance, context, level)
stream.write("}")
stream.write(")")
_dispatch[_collections.Counter.__repr__] = _pprint_counter
def _pprint_chain_map(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
if not len(object.maps) or (len(object.maps) == 1 and not len(object.maps[0])):
stream.write(repr(object))
return
stream.write(object.__class__.__name__ + "(")
self._format_items(object.maps, stream, indent, allowance, context, level)
stream.write(")")
_dispatch[_collections.ChainMap.__repr__] = _pprint_chain_map
def _pprint_deque(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
stream.write(object.__class__.__name__ + "(")
if object.maxlen is not None:
stream.write("maxlen=%d, " % object.maxlen)
stream.write("[")
self._format_items(object, stream, indent, allowance + 1, context, level)
stream.write("])")
_dispatch[_collections.deque.__repr__] = _pprint_deque
def _pprint_user_dict(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
self._format(object.data, stream, indent, allowance, context, level - 1)
_dispatch[_collections.UserDict.__repr__] = _pprint_user_dict
def _pprint_user_list(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
self._format(object.data, stream, indent, allowance, context, level - 1)
_dispatch[_collections.UserList.__repr__] = _pprint_user_list
def _pprint_user_string(
self,
object: Any,
stream: IO[str],
indent: int,
allowance: int,
context: Set[int],
level: int,
) -> None:
self._format(object.data, stream, indent, allowance, context, level - 1)
_dispatch[_collections.UserString.__repr__] = _pprint_user_string
def _safe_repr(
self, object: Any, context: Set[int], maxlevels: Optional[int], level: int
) -> str:
typ = type(object)
if typ in _builtin_scalars:
return repr(object)
r = getattr(typ, "__repr__", None)
if issubclass(typ, dict) and r is dict.__repr__:
if not object:
return "{}"
objid = id(object)
if maxlevels and level >= maxlevels:
return "{...}"
if objid in context:
return _recursion(object)
context.add(objid)
components: List[str] = []
append = components.append
level += 1
for k, v in sorted(object.items(), key=_safe_tuple):
krepr = self._safe_repr(k, context, maxlevels, level)
vrepr = self._safe_repr(v, context, maxlevels, level)
append(f"{krepr}: {vrepr}")
context.remove(objid)
return "{%s}" % ", ".join(components)
if (issubclass(typ, list) and r is list.__repr__) or (
issubclass(typ, tuple) and r is tuple.__repr__
):
if issubclass(typ, list):
if not object:
return "[]"
format = "[%s]"
elif len(object) == 1:
format = "(%s,)"
else:
if not object:
return "()"
format = "(%s)"
objid = id(object)
if maxlevels and level >= maxlevels:
return format % "..."
if objid in context:
return _recursion(object)
context.add(objid)
components = []
append = components.append
level += 1
for o in object:
orepr = self._safe_repr(o, context, maxlevels, level)
append(orepr)
context.remove(objid)
return format % ", ".join(components)
return repr(object)
_builtin_scalars = frozenset(
{str, bytes, bytearray, float, complex, bool, type(None), int}
)
def _recursion(object: Any) -> str:
return f"<Recursion on {type(object).__name__} with id={id(object)}>"
def _wrap_bytes_repr(object: Any, width: int, allowance: int) -> Iterator[str]:
current = b""
last = len(object) // 4 * 4
for i in range(0, len(object), 4):
part = object[i : i + 4]
candidate = current + part
if i == last:
width -= allowance
if len(repr(candidate)) > width:
if current:
yield repr(current)
current = part
else:
current = candidate
if current:
yield repr(current)