def _parse_empty_line(
config: BaseWhitespaceParserConfig,
state: State,
*,
override_absolute_indent: Optional[str] = None,
) -> Optional[EmptyLine]:
# begin speculative parsing
speculative_state = State(state.line, state.column, state.absolute_indent,
state.is_parenthesized)
try:
indent = _parse_indent(
config,
speculative_state,
override_absolute_indent=override_absolute_indent)
except Exception:
# We aren't on a new line, speculative parsing failed
return None
whitespace = parse_simple_whitespace(config, speculative_state)
comment = _parse_comment(config, speculative_state)
newline = _parse_newline(config, speculative_state)
if newline is None:
# speculative parsing failed
return None
# speculative parsing succeeded
state.line = speculative_state.line
state.column = speculative_state.column
# don't need to copy absolute_indent/is_parenthesized because they don't change.
return EmptyLine(indent, whitespace, comment, newline)
def parse_empty_lines(
config: BaseWhitespaceParserConfig,
state: State,
*,
override_absolute_indent: Optional[str] = None,
) -> Sequence[EmptyLine]:
# If override_absolute_indent is true, then we need to parse all lines up
# to and including the last line that is indented at our level. These all
# belong to the footer and not to the next line's leading_lines. All lines
# that have indent=False and come after the last line where indent=True
# do not belong to this node.
state_for_line = State(state.line, state.column, state.absolute_indent,
state.is_parenthesized)
lines: List[Tuple[State, EmptyLine]] = []
while True:
el = _parse_empty_line(
config,
state_for_line,
override_absolute_indent=override_absolute_indent)
if el is None:
break
# Store the updated state with the element we parsed. Then make a new state
# clone for the next element.
lines.append((state_for_line, el))
state_for_line = State(
state_for_line.line,
state_for_line.column,
state.absolute_indent,
state.is_parenthesized,
)
if override_absolute_indent is not None:
# We need to find the last element that is indented, and then split the list
# at that point.
for i in range(len(lines) - 1, -1, -1):
if lines[i][1].indent:
lines = lines[:(i + 1)]
break
else:
# We didn't find any lines, throw them all away
lines = []
if lines:
# Update the state line and column to match the last line actually parsed.
final_state: State = lines[-1][0]
state.line = final_state.line
state.column = final_state.column
return [r[1] for r in lines]
def _parse_trailing_whitespace(config: BaseWhitespaceParserConfig,
state: State) -> Optional[TrailingWhitespace]:
# Begin speculative parsing
speculative_state = State(state.line, state.column, state.absolute_indent,
state.is_parenthesized)
whitespace = parse_simple_whitespace(config, speculative_state)
comment = _parse_comment(config, speculative_state)
newline = _parse_newline(config, speculative_state)
if newline is None:
# Speculative parsing failed
return None
# Speculative parsing succeeded
state.line = speculative_state.line
state.column = speculative_state.column
# don't need to copy absolute_indent/is_parenthesized because they don't change.
return TrailingWhitespace(whitespace, comment, newline)