def lib2to3_parse(
src_txt: str, target_versions: Iterable[TargetVersion] = ()) -> Node:
"""Given a string with source, return the lib2to3 Node."""
if not src_txt.endswith("\n"):
src_txt += "\n"
for grammar in get_grammars(set(target_versions)):
drv = driver.Driver(grammar, pytree.convert)
try:
result = drv.parse_string(src_txt, True)
break
except ParseError as pe:
lineno, column = pe.context[1]
lines = src_txt.splitlines()
try:
faulty_line = lines[lineno - 1]
except IndexError:
faulty_line = "<line number missing in source>"
exc = InvalidInput(
f"Cannot parse: {lineno}:{column}: {faulty_line}")
else:
raise exc from None
if isinstance(result, Leaf):
result = Node(syms.file_input, [result])
return result
def matches_grammar(src_txt: str, grammar: Grammar) -> bool:
drv = driver.Driver(grammar)
try:
drv.parse_string(src_txt, True)
except (ParseError, TokenError, IndentationError):
return False
else:
return True
def lib2to3_parse(
src_txt: str, target_versions: Iterable[TargetVersion] = ()) -> Node:
"""Given a string with source, return the lib2to3 Node."""
if not src_txt.endswith("\n"):
src_txt += "\n"
grammars = get_grammars(set(target_versions))
errors = {}
for grammar in grammars:
drv = driver.Driver(grammar)
try:
result = drv.parse_string(src_txt, True)
break
except ParseError as pe:
lineno, column = pe.context[1]
lines = src_txt.splitlines()
try:
faulty_line = lines[lineno - 1]
except IndexError:
faulty_line = "<line number missing in source>"
errors[grammar.version] = InvalidInput(
f"Cannot parse: {lineno}:{column}: {faulty_line}")
except TokenError as te:
# In edge cases these are raised; and typically don't have a "faulty_line".
lineno, column = te.args[1]
errors[grammar.version] = InvalidInput(
f"Cannot parse: {lineno}:{column}: {te.args[0]}")
else:
# Choose the latest version when raising the actual parsing error.
assert len(errors) >= 1
exc = errors[max(errors)]
if matches_grammar(src_txt, pygram.python_grammar) or matches_grammar(
src_txt, pygram.python_grammar_no_print_statement):
original_msg = exc.args[0]
msg = f"{original_msg}\n{PY2_HINT}"
raise InvalidInput(msg) from None
raise exc from None
if isinstance(result, Leaf):
result = Node(syms.file_input, [result])
return result
def lib2to3_parse(src_txt: str) -> Node:
"""Given a string with source, return the lib2to3 Node."""
grammar = pygram.python_grammar_no_print_statement
drv = driver.Driver(grammar, pytree.convert)
if src_txt[-1] != '\n':
nl = '\r\n' if '\r\n' in src_txt[:1024] else '\n'
src_txt += nl
try:
result = drv.parse_string(src_txt, True)
except ParseError as pe:
lineno, column = pe.context[1]
lines = src_txt.splitlines()
try:
faulty_line = lines[lineno - 1]
except IndexError:
faulty_line = "<line number missing in source>"
raise ValueError(f"Cannot parse: {lineno}:{column}: {faulty_line}") from None
if isinstance(result, Leaf):
result = Node(syms.file_input, [result])
return result