import re
from typing import Any
from pip._internal.utils.compat import tomllib
REGEX = r"(?m)^# /// (?P<type>[a-zA-Z0-9-]+)$\s(?P<content>(^#(| .*)$\s)+)^# ///$"
class PEP723Exception(ValueError):
"""Raised to indicate a problem when parsing PEP 723 metadata from a script"""
def __init__(self, msg: str) -> None:
self.msg = msg
def pep723_metadata(scriptfile: str) -> dict[str, Any]:
with open(scriptfile) as f:
script = f.read()
name = "script"
matches = list(
filter(lambda m: m.group("type") == name, re.finditer(REGEX, script))
)
if len(matches) > 1:
raise PEP723Exception(f"Multiple {name!r} blocks found in {scriptfile!r}")
elif len(matches) == 1:
content = "".join(
line[2:] if line.startswith("# ") else line[1:]
for line in matches[0].group("content").splitlines(keepends=True)
)
try:
metadata = tomllib.loads(content)
except Exception as exc:
raise PEP723Exception(f"Failed to parse TOML in {scriptfile!r}") from exc
else:
raise PEP723Exception(
f"File does not contain {name!r} metadata: {scriptfile!r}"
)
return metadata