Method do_match

src/black/trans.py:425–472

(self, line: Line)

    """

    def do_match(self, line: Line) -> TMatchResult:
        LL = line.leaves

        is_valid_index = is_valid_index_factory(LL)

        string_indices = []
        idx = 0
        while is_valid_index(idx):
            leaf = LL[idx]
            if (
                leaf.type == token.STRING
                and is_valid_index(idx + 1)
                and LL[idx + 1].type == token.STRING
            ):
                # Let's check if the string group contains an inline comment
                # If we have a comment inline, we don't merge the strings
                contains_comment = False
                i = idx
                while is_valid_index(i):
                    if LL[i].type != token.STRING:
                        break
                    if line.comments_after(LL[i]):
                        contains_comment = True
                        break
                    i += 1

                if not contains_comment and not is_part_of_annotation(leaf):
                    string_indices.append(idx)

                # Advance to the next non-STRING leaf.
                idx += 2
                while is_valid_index(idx) and LL[idx].type == token.STRING:
                    idx += 1

            elif leaf.type == token.STRING and "\\\n" in leaf.value:
                string_indices.append(idx)
                # Advance to the next non-STRING leaf.
                idx += 1
                while is_valid_index(idx) and LL[idx].type == token.STRING:
                    idx += 1

            else:
                idx += 1

        if string_indices:
            return Ok(string_indices)
        else:
            return TErr("This line has no strings that need merging.")

    def do_transform(
        self, line: Line, string_indices: list[int]