Don't fail if clang-tidy-checks.py can't be written

[hannesweisbach]

Hello and thanks for this awesome tool!

To be honest, I don't fully understand why clang-tidy-checks.py is written and what it is for. But I think it should be possible to write the generated HTML to stdout, like it is common in Unix tools. For example allow a syntax as follows:

clang-tidy-html <file> -o -

Of course I can work around that using process substitution:

 clang-tidy-html clang-tidy.log -o >(cat)

however that fails, because clang-tidy-checks.py can't be written:

Traceback (most recent call last):
  File "/home/weisbach/.local/bin/clang-tidy-html", line 8, in <module>
    sys.exit(main())
  File "/home/weisbach/.local/lib/python3.10/site-packages/clang_html/clang_visualizer.py", line 89, in main
    clang_tidy_visualizer(tidy_log_lines, output_path, args.checks_dict_url)
  File "/home/weisbach/.local/lib/python3.10/site-packages/clang_html/clang_visualizer.py", line 110, in clang_tidy_visualizer
    write_checks_file(
  File "/home/weisbach/.local/lib/python3.10/site-packages/clang_html/clang_visualizer.py", line 221, in write_checks_file
    with open(to_file, 'w') as f:
FileNotFoundError: [Errno 2] No such file or directory: '/dev/fd/clang-tidy-checks.py'

which is really unfortunate.

Currently I'm working around this issue with the code change:

try:
    write_checks_file(
        checks_list, to_file=output_html_file.parent / "clang-tidy-checks.py")
except FileNotFoundError:
    print(f"Could not create {output_html_file.parent}/clang-tidy-checks.py", file=sys.stderr)

But that is very clunky and I'd rather have a stock solution.

Perhaps generation of clang-tidy-checks.py can be omitted if writing to stdout? Or generation of clang-tidy-checks.py can be enabled/disabled via a command line option? I'd be willing to make the necessary changes and submit a PR.

Best regards, Hannes

(At the same time it would probably be nice to have clang-tidy-html read the log from stdin)