lucasvl.nl/lib/python3.11/site-packages/werkzeug/debug/repr.py

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2024-03-04 21:31:20 -06:00
"""Object representations for debugging purposes. Unlike the default
repr, these expose more information and produce HTML instead of ASCII.
Together with the CSS and JavaScript of the debugger this gives a
colorful and more compact output.
"""
from __future__ import annotations
import codecs
import re
import sys
import typing as t
from collections import deque
from traceback import format_exception_only
from markupsafe import escape
missing = object()
_paragraph_re = re.compile(r"(?:\r\n|\r|\n){2,}")
RegexType = type(_paragraph_re)
HELP_HTML = """\
<div class=box>
<h3>%(title)s</h3>
<pre class=help>%(text)s</pre>
</div>\
"""
OBJECT_DUMP_HTML = """\
<div class=box>
<h3>%(title)s</h3>
%(repr)s
<table>%(items)s</table>
</div>\
"""
def debug_repr(obj: object) -> str:
"""Creates a debug repr of an object as HTML string."""
return DebugReprGenerator().repr(obj)
def dump(obj: object = missing) -> None:
"""Print the object details to stdout._write (for the interactive
console of the web debugger.
"""
gen = DebugReprGenerator()
if obj is missing:
rv = gen.dump_locals(sys._getframe(1).f_locals)
else:
rv = gen.dump_object(obj)
sys.stdout._write(rv) # type: ignore
class _Helper:
"""Displays an HTML version of the normal help, for the interactive
debugger only because it requires a patched sys.stdout.
"""
def __repr__(self) -> str:
return "Type help(object) for help about object."
def __call__(self, topic: t.Any | None = None) -> None:
if topic is None:
sys.stdout._write(f"<span class=help>{self!r}</span>") # type: ignore
return
import pydoc
pydoc.help(topic)
rv = sys.stdout.reset() # type: ignore
paragraphs = _paragraph_re.split(rv)
if len(paragraphs) > 1:
title = paragraphs[0]
text = "\n\n".join(paragraphs[1:])
else:
title = "Help"
text = paragraphs[0]
sys.stdout._write(HELP_HTML % {"title": title, "text": text}) # type: ignore
helper = _Helper()
def _add_subclass_info(
inner: str, obj: object, base: t.Type | tuple[t.Type, ...]
) -> str:
if isinstance(base, tuple):
for cls in base:
if type(obj) is cls:
return inner
elif type(obj) is base:
return inner
module = ""
if obj.__class__.__module__ not in ("__builtin__", "exceptions"):
module = f'<span class="module">{obj.__class__.__module__}.</span>'
return f"{module}{type(obj).__name__}({inner})"
def _sequence_repr_maker(
left: str, right: str, base: t.Type, limit: int = 8
) -> t.Callable[[DebugReprGenerator, t.Iterable, bool], str]:
def proxy(self: DebugReprGenerator, obj: t.Iterable, recursive: bool) -> str:
if recursive:
return _add_subclass_info(f"{left}...{right}", obj, base)
buf = [left]
have_extended_section = False
for idx, item in enumerate(obj):
if idx:
buf.append(", ")
if idx == limit:
buf.append('<span class="extended">')
have_extended_section = True
buf.append(self.repr(item))
if have_extended_section:
buf.append("</span>")
buf.append(right)
return _add_subclass_info("".join(buf), obj, base)
return proxy
class DebugReprGenerator:
def __init__(self) -> None:
self._stack: list[t.Any] = []
list_repr = _sequence_repr_maker("[", "]", list)
tuple_repr = _sequence_repr_maker("(", ")", tuple)
set_repr = _sequence_repr_maker("set([", "])", set)
frozenset_repr = _sequence_repr_maker("frozenset([", "])", frozenset)
deque_repr = _sequence_repr_maker(
'<span class="module">collections.</span>deque([', "])", deque
)
def regex_repr(self, obj: t.Pattern) -> str:
pattern = repr(obj.pattern)
pattern = codecs.decode(pattern, "unicode-escape", "ignore")
pattern = f"r{pattern}"
return f're.compile(<span class="string regex">{pattern}</span>)'
def string_repr(self, obj: str | bytes, limit: int = 70) -> str:
buf = ['<span class="string">']
r = repr(obj)
# shorten the repr when the hidden part would be at least 3 chars
if len(r) - limit > 2:
buf.extend(
(
escape(r[:limit]),
'<span class="extended">',
escape(r[limit:]),
"</span>",
)
)
else:
buf.append(escape(r))
buf.append("</span>")
out = "".join(buf)
# if the repr looks like a standard string, add subclass info if needed
if r[0] in "'\"" or (r[0] == "b" and r[1] in "'\""):
return _add_subclass_info(out, obj, (bytes, str))
# otherwise, assume the repr distinguishes the subclass already
return out
def dict_repr(
self,
d: dict[int, None] | dict[str, int] | dict[str | int, int],
recursive: bool,
limit: int = 5,
) -> str:
if recursive:
return _add_subclass_info("{...}", d, dict)
buf = ["{"]
have_extended_section = False
for idx, (key, value) in enumerate(d.items()):
if idx:
buf.append(", ")
if idx == limit - 1:
buf.append('<span class="extended">')
have_extended_section = True
buf.append(
f'<span class="pair"><span class="key">{self.repr(key)}</span>:'
f' <span class="value">{self.repr(value)}</span></span>'
)
if have_extended_section:
buf.append("</span>")
buf.append("}")
return _add_subclass_info("".join(buf), d, dict)
def object_repr(self, obj: type[dict] | t.Callable | type[list] | None) -> str:
r = repr(obj)
return f'<span class="object">{escape(r)}</span>'
def dispatch_repr(self, obj: t.Any, recursive: bool) -> str:
if obj is helper:
return f'<span class="help">{helper!r}</span>'
if isinstance(obj, (int, float, complex)):
return f'<span class="number">{obj!r}</span>'
if isinstance(obj, str) or isinstance(obj, bytes):
return self.string_repr(obj)
if isinstance(obj, RegexType):
return self.regex_repr(obj)
if isinstance(obj, list):
return self.list_repr(obj, recursive)
if isinstance(obj, tuple):
return self.tuple_repr(obj, recursive)
if isinstance(obj, set):
return self.set_repr(obj, recursive)
if isinstance(obj, frozenset):
return self.frozenset_repr(obj, recursive)
if isinstance(obj, dict):
return self.dict_repr(obj, recursive)
if isinstance(obj, deque):
return self.deque_repr(obj, recursive)
return self.object_repr(obj)
def fallback_repr(self) -> str:
try:
info = "".join(format_exception_only(*sys.exc_info()[:2]))
except Exception:
info = "?"
return (
'<span class="brokenrepr">'
f"&lt;broken repr ({escape(info.strip())})&gt;</span>"
)
def repr(self, obj: object) -> str:
recursive = False
for item in self._stack:
if item is obj:
recursive = True
break
self._stack.append(obj)
try:
try:
return self.dispatch_repr(obj, recursive)
except Exception:
return self.fallback_repr()
finally:
self._stack.pop()
def dump_object(self, obj: object) -> str:
repr = None
items: list[tuple[str, str]] | None = None
if isinstance(obj, dict):
title = "Contents of"
items = []
for key, value in obj.items():
if not isinstance(key, str):
items = None
break
items.append((key, self.repr(value)))
if items is None:
items = []
repr = self.repr(obj)
for key in dir(obj):
try:
items.append((key, self.repr(getattr(obj, key))))
except Exception:
pass
title = "Details for"
title += f" {object.__repr__(obj)[1:-1]}"
return self.render_object_dump(items, title, repr)
def dump_locals(self, d: dict[str, t.Any]) -> str:
items = [(key, self.repr(value)) for key, value in d.items()]
return self.render_object_dump(items, "Local variables in frame")
def render_object_dump(
self, items: list[tuple[str, str]], title: str, repr: str | None = None
) -> str:
html_items = []
for key, value in items:
html_items.append(f"<tr><th>{escape(key)}<td><pre class=repr>{value}</pre>")
if not html_items:
html_items.append("<tr><td><em>Nothing</em>")
return OBJECT_DUMP_HTML % {
"title": escape(title),
"repr": f"<pre class=repr>{repr if repr else ''}</pre>",
"items": "\n".join(html_items),
}