[clang-format]: `ColumnLimit` as one option, should not contain two different rules

[scruel]

IMO, ColumnLimit should only do its literal rule, just like max_line_length in .editorconfig.
For respecting the input's line breaking decisions, I think we can consider provide a new option called RespectExistLineBreaks to do the ColumnLimit: 0 job?
Because I want clang-format to respect the line breaks I wrote, but keep breaking too long lines (contradict other rules).

Furthermore, can consider just deprecate the ColumnLimit option, and replace it by two options called maxLineLength: [int] and RespectExistLineBreaks: [boolean] will be better:

  /// This option is deprecated. See MaxLineLength and RespectExistLineBreaks.
  /// \version 3.7
  unsigned ColumnLimit;
  
  /// The max line length.
  ///
  /// Forces hard line wrapping after the amount of characters specified.
  /// \version <release-version>
  bool MaxLineLength;

  /// If ``true`` clang-format will respect the input's line breaking decisions
  /// within statements unless they contradict other rules.
  /// \version <release-version>
  bool RespectExistLineBreaks;

Might related to:

• clang-format ColumnLimit=0 produces very long condition lines #23201
• https://stackoverflow.com/questions/33656800/clang-format-line-breaks

[llvmbot]

@llvm/issue-subscribers-clang-format

[daschuer]

In Mixxx, we have the same demand.

clang-format breaks the lines in a way to make the best of the allowed space. In many cases that is not as readable as it could be. In cases where a line break is required we like to put it manual in the best place, which can be anywhere.

We have implemented a workaround with git-clang-format and pre-commit doing a two passes of clang-format.
The first run formats all changed lines with ColumnLimit = 0
Than we check for manual for lines longer 100 columns and format them with clang-format and a ColumnLimit = 80

This solves the following things:

• Preserves manual line breaks, in manual optimized positions.
• Allows 100 columns but puts line breaks before 80. This gives the developer a freedom for longer lines and makes sure that the second line is reasonable long after a automatic line break.

The wrapper script can be found here:
https://github.com/mixxxdj/mixxx/blob/main/tools/clang_format.py#L15

However, we have pending issues on Windows discussed here
mixxxdj/mixxx#10972

[daschuer]

The Windows issue withe the Mixxx workaround has been solved here mixxxdj/mixxx#11004. Is there any news with this feature request?

[ferdymercury]

This would be indeed a very useful feature.