Method maybe_append_string_operators

src/black/trans.py:1548–1559

Side Effects: If @line starts with a string operator and this is the first line we are constructing, this function appends the string operator to @new_line and replaces the old string operator leaf in the node structure. Ot

(new_line: Line)

        )

        def maybe_append_string_operators(new_line: Line) -> None:
            """
            Side Effects:
                If @line starts with a string operator and this is the first
                line we are constructing, this function appends the string
                operator to @new_line and replaces the old string operator leaf
                in the node structure. Otherwise this function does nothing.
            """
            maybe_prefix_leaves = string_op_leaves if first_string_line else []
            for i, prefix_leaf in enumerate(maybe_prefix_leaves):
                replace_child(LL[i], prefix_leaf)
                new_line.append(prefix_leaf)

        ends_with_comma = (
            is_valid_index(string_idx + 1) and LL[string_idx + 1].type == token.COMMA