def convert_file_input(config: ParserConfig, children: Sequence[Any]) -> Any:
*body, footer = children
if len(body) == 0:
# If there's no body, the header and footer are ambiguous. The header is more
# important, and should own the EmptyLine nodes instead of the footer.
header = footer
footer = ()
if (len(config.lines) == 2 and NEWLINE_RE.fullmatch(config.lines[0])
and config.lines[1] == ""):
# This is an empty file (not even a comment), so special-case this to an
# empty list instead of a single dummy EmptyLine (which is what we'd
# normally parse).
header = ()
else:
# Steal the leading lines from the first statement, and move them into the
# header.
first_stmt = body[0]
header = first_stmt.leading_lines
body[0] = first_stmt.with_changes(leading_lines=())
return Module(
header=header,
body=body,
footer=footer,
encoding=config.encoding,
default_indent=config.default_indent,
default_newline=config.default_newline,
has_trailing_newline=config.has_trailing_newline,
)
def _detect_trailing_newline(source_str: str) -> bool:
if len(source_str) == 0 or not NEWLINE_RE.fullmatch(source_str[-1]):
return False
# Make sure that the last newline wasn't following a continuation
return not (
_CONTINUATION_RE.fullmatch(source_str[-2:])
or _CONTINUATION_RE.fullmatch(source_str[-3:])
)
def __post_init__(self) -> None:
raw_python_version = self.python_version
if isinstance(raw_python_version, AutoConfig):
# If unspecified, we'll try to pick the same as the running
# interpreter. There will always be at least one entry.
parsed_python_version = _pick_compatible_python_version()
else:
# If the caller specified a version, we require that to be a known
# version (because we don't want to encourage doing duplicate work
# when there weren't syntax changes).
# `parse_version_string` will raise a ValueError if the version is
# invalid.
parsed_python_version = parse_version_string(raw_python_version)
if not any(
parsed_python_version == parse_version_string(v)
for v in KNOWN_PYTHON_VERSION_STRINGS
):
comma_versions = ", ".join(KNOWN_PYTHON_VERSION_STRINGS)
raise ValueError(
"LibCST can only parse code using one of the following versions of "
+ f"Python's grammar: {comma_versions}. More versions may be "
+ "supported by future releases."
)
# We use object.__setattr__ because the dataclass is frozen. See:
# https://docs.python.org/3/library/dataclasses.html#frozen-instances
# This should be safe behavior inside of `__post_init__`.
object.__setattr__(self, "parsed_python_version", parsed_python_version)
encoding = self.encoding
if not isinstance(encoding, AutoConfig):
try:
codecs.lookup(encoding)
except LookupError:
raise ValueError(f"{repr(encoding)} is not a supported encoding")
newline = self.default_newline
if (
not isinstance(newline, AutoConfig)
and NEWLINE_RE.fullmatch(newline) is None
):
raise ValueError(
f"Got an invalid value for default_newline: {repr(newline)}"
)
indent = self.default_indent
if not isinstance(indent, AutoConfig) and _INDENT_RE.fullmatch(indent) is None:
raise ValueError(f"Got an invalid value for default_indent: {repr(indent)}")
def __post_init__(self) -> None:
raw_python_version = self.python_version
# `parse_version_string` will raise a ValueError if the version is invalid.
#
# We use object.__setattr__ because the dataclass is frozen. See:
# https://docs.python.org/3/library/dataclasses.html#frozen-instances
# This should be safe behavior inside of `__post_init__`.
parsed_python_version = parse_version_string(None if isinstance(
raw_python_version, AutoConfig) else raw_python_version)
# Once we add support for more versions of Python, we can change this to detect
# the supported version range.
if parsed_python_version not in (
PythonVersionInfo(3, 5),
PythonVersionInfo(3, 6),
PythonVersionInfo(3, 7),
PythonVersionInfo(3, 8),
):
raise ValueError(
"LibCST can only parse code using one of the following versions of "
+
"Python's grammar: 3.5, 3.6, 3.7, 3.8. More versions may be " +
"supported by future releases.")
object.__setattr__(self, "parsed_python_version",
parsed_python_version)
encoding = self.encoding
if not isinstance(encoding, AutoConfig):
try:
codecs.lookup(encoding)
except LookupError:
raise ValueError(
f"{repr(encoding)} is not a supported encoding")
newline = self.default_newline
if (not isinstance(newline, AutoConfig)
and NEWLINE_RE.fullmatch(newline) is None):
raise ValueError(
f"Got an invalid value for default_newline: {repr(newline)}")
indent = self.default_indent
if not isinstance(indent,
AutoConfig) and _INDENT_RE.fullmatch(indent) is None:
raise ValueError(
f"Got an invalid value for default_indent: {repr(indent)}")