def _fix_eval_field_params(self):
"""Replace f-string field ID placeholders with the actual field
expressions."""
for node in ast.walk(self.res):
if not (
isinstance(node, ast.Call)
and node.func.value.id == "__xonsh__"
and node.func.attr == "eval_fstring_field"
and len(node.args) > 0
):
continue
if PYTHON_VERSION_INFO > (3, 8):
if isinstance(node.args[0], ast.Constant) and isinstance(
node.args[0].value, int
):
field = self.fields.pop(node.args[0].value, None)
if field is None:
continue
lineno = node.args[0].lineno
col_offset = node.args[0].col_offset
field_node = ast.Tuple(
elts=[
ast.Constant(
value=field[0], lineno=lineno, col_offset=col_offset
),
ast.Constant(
value=field[1], lineno=lineno, col_offset=col_offset
),
],
ctx=ast.Load(),
lineno=lineno,
col_offset=col_offset,
)
node.args[0] = field_node
elif isinstance(node.args[0], ast.Num):
field = self.fields.pop(node.args[0].n, None)
if field is None:
continue
lineno = node.args[0].lineno
col_offset = node.args[0].col_offset
elts = [ast.Str(s=field[0], lineno=lineno, col_offset=col_offset)]
if field[1] is not None:
elts.append(
ast.Str(s=field[1], lineno=lineno, col_offset=col_offset)
)
else:
elts.append(
ast.NameConstant(
value=None, lineno=lineno, col_offset=col_offset
)
)
field_node = ast.Tuple(
elts=elts, ctx=ast.Load(), lineno=lineno, col_offset=col_offset,
)
node.args[0] = field_node
def _unpatch_strings(self):
"""Reverts false-positive field matches within strings."""
reparse = False
for node in ast.walk(self.res):
if isinstance(node, ast.Constant) and isinstance(node.value, str):
value = node.value
elif isinstance(node, ast.Str):
value = node.s
else:
continue
match = RE_FSTR_FIELD_WRAPPER.search(value)
if match is None:
continue
field = self.fields.pop(int(match.group(2)), None)
if field is None:
continue
self.repl = self.repl.replace(match.group(1), field[0], 1)
reparse = True
if reparse:
self.res = pyparse(self.repl).body[0].value
def _unpatch_selfdoc_strings(self):
"""Reverts false-positive matches within Python 3.8 sef-documenting
f-string expressions."""
for node in ast.walk(self.res):
if isinstance(node, ast.Constant) and isinstance(node.value, str):
value = node.value
elif isinstance(node, ast.Str):
value = node.s
else:
continue
match = RE_FSTR_SELF_DOC_FIELD_WRAPPER.search(value)
if match is None:
continue
field = self.fields.get(int(match.group(2)), None)
if field is None:
continue
value = value.replace(match.group(1), field[0], 1)
if isinstance(node, ast.Str):
node.s = value
else:
node.value = value
