def transform(self, node: ast.Call) -> ast.Call:
new_call = ast.Call(parent=node.parent)
new_name = ast.Name(self.new_name, parent=new_call.parent)
new_call.postinit(func=new_name,
args=node.args,
keywords=node.keywords)
return new_call
def transform(self, node: ast.Assign) -> ast.Assign:
new_assign = ast.Assign(parent=node.parent)
value = ast.Call(parent=new_assign)
iterator = node.value.generators[0].iter
iterator.parent = value
value.postinit(
func=ast.Name(name="map", parent=value),
args=[ast.Name(node.value.elt.func.name, parent=value), iterator])
targets = node.targets
for target in targets:
target.parent = new_assign
new_assign.postinit(targets=node.targets, value=value)
return new_assign
def convert_f_string_to_format_string(src: str) -> str:
"""
Convert a single f-string (passed as its source token)
to a .format() call (as a source token).
"""
node = astroid.extract_node(src)
# An f-string alternates between two kinds of nodes: string Const nodes and
# FormattedValue nodes that hold the formatting bits
format_string_parts = []
format_args = []
for child in node.get_children():
if isinstance(child, astroid.Const):
format_string_parts.append(child.value)
elif isinstance(child, astroid.FormattedValue):
format_string_parts.append(
"{{{c}{f}}}".format(
c=CONVERSIONS[child.conversion],
f=f":{child.format_spec.values[0].value}"
if child.format_spec is not None
else "",
)
)
# We can pick the format value nodes right out of the string
# and place them in the args; no need to introspect what they
# actually are!
format_args.append(child.value)
format_string_node = astroid.Const("".join(format_string_parts))
format_call = astroid.Call(lineno=node.lineno, col_offset=node.col_offset)
# The Call's func is a method looked up on the format string
format_attr = astroid.Attribute(attrname="format", lineno=node.lineno, parent=format_call)
format_attr.postinit(expr=format_string_node)
# The Call's arguments are the format arguments extracted from the f-string
format_call.postinit(func=format_attr, args=format_args, keywords=[])
return format_call.as_string()