clang-format: Function-try blocks are formatted incorrectly

[llvmbot]

Bugzilla Link	20615
Version	trunk
OS	Linux
Reporter	LLVM Bugzilla Contributor

Extended Description

Example:

  int main(int argv, char *argv[])
  try {
      // something
      return 0;
  } catch (std::exception const &e) {
      // something else
      return 1;
  }

Attach

// {BasedOnStyle: LLVM}

  int main(int argv, char *argv[]) try {
    // something
    return 0;
  } catch (std::exception const &e) {
    // something else
    return 1;
  }

Stroustrup

// {BasedOnStyle: LLVM, BreakBeforeBrace: Stroustrup}

  int main(int argv, char *argv[]) try {
    // something
    return 0;
  }
  catch (std::exception const &e) {
    // something else
    return 1;
  }

Allman

// {BasedOnStyle: LLVM, BreakBeforeBrace: Allman}

  int main(int argv, char *argv[]) try
  {
    // something
    return 0;
  }
  catch (std::exception const &e)
  {
    // something else
    return 1;
  }

I believe there should be break before the try keyword.

[mydeveloperday]

Do we think this is subjective or objective? I honestly don't think we'd bother to fix this? who writes functions without braces?

[ace575]

This is completely subjective. After all, the function-try-block is an alternate function body, part of the function definition and therefore is closer to noexcept and const. It is not inside the function body.

They can be useful for avoiding indenting the entire body of a function an extra level of indentation just to make a function noexcept.

Why was the behavior here arbitrarily changed? https://discourse.llvm.org/t/a-question-regarding-formatting-of-function-try-block/49857

This seems like an area where a .clang-format option should be available to determine where to put the 'try' for Allman style braces: https://godbolt.org/z/KTGdYPxGd

[sylveon]

I'm of the opinion it should be part of the same line as a function (like other qualifiers), and am disappointed there isn't an option to modify this behavior.