Split line into many lines, starting with the first matching bracket pair. Note: this usually looks weird, only use this for function definitions. Prefer RHS otherwise. This is why this function is not symmetrical with :func:`right_hand_split` which also handles optional parentheses.
(
line: Line, _features: Collection[Feature], mode: Mode
)
| 873 | |
| 874 | |
| 875 | def left_hand_split( |
| 876 | line: Line, _features: Collection[Feature], mode: Mode |
| 877 | ) -> Iterator[Line]: |
| 878 | """Split line into many lines, starting with the first matching bracket pair. |
| 879 | |
| 880 | Note: this usually looks weird, only use this for function definitions. |
| 881 | Prefer RHS otherwise. This is why this function is not symmetrical with |
| 882 | :func:`right_hand_split` which also handles optional parentheses. |
| 883 | """ |
| 884 | for leaf_type in [token.LPAR, token.LSQB]: |
| 885 | tail_leaves: list[Leaf] = [] |
| 886 | body_leaves: list[Leaf] = [] |
| 887 | head_leaves: list[Leaf] = [] |
| 888 | current_leaves = head_leaves |
| 889 | matching_bracket: Leaf | None = None |
| 890 | depth = 0 |
| 891 | for index, leaf in enumerate(line.leaves): |
| 892 | if index == 2 and leaf.type == token.LSQB: |
| 893 | # A [ at index 2 means this is a type param, so start |
| 894 | # tracking the depth |
| 895 | depth += 1 |
| 896 | elif depth > 0: |
| 897 | if leaf.type == token.LSQB: |
| 898 | depth += 1 |
| 899 | elif leaf.type == token.RSQB: |
| 900 | depth -= 1 |
| 901 | if ( |
| 902 | current_leaves is body_leaves |
| 903 | and leaf.type in CLOSING_BRACKETS |
| 904 | and leaf.opening_bracket is matching_bracket |
| 905 | and isinstance(matching_bracket, Leaf) |
| 906 | # If the code is still on LPAR and we are inside a type |
| 907 | # param, ignore the match since this is searching |
| 908 | # for the function arguments |
| 909 | and not (leaf_type == token.LPAR and depth > 0) |
| 910 | ): |
| 911 | ensure_visible(leaf) |
| 912 | ensure_visible(matching_bracket) |
| 913 | current_leaves = tail_leaves if body_leaves else head_leaves |
| 914 | current_leaves.append(leaf) |
| 915 | if current_leaves is head_leaves: |
| 916 | if leaf.type == leaf_type and ( |
| 917 | not (leaf_type == token.LPAR and depth > 0) |
| 918 | ): |
| 919 | matching_bracket = leaf |
| 920 | current_leaves = body_leaves |
| 921 | if matching_bracket and tail_leaves: |
| 922 | break |
| 923 | if not matching_bracket or not tail_leaves: |
| 924 | raise CannotSplit("No brackets found") |
| 925 | |
| 926 | head = bracket_split_build_line( |
| 927 | head_leaves, line, matching_bracket, component=_BracketSplitComponent.head |
| 928 | ) |
| 929 | body = bracket_split_build_line( |
| 930 | body_leaves, line, matching_bracket, component=_BracketSplitComponent.body |
| 931 | ) |
| 932 | tail = bracket_split_build_line( |
nothing calls this directly
no test coverage detected