cmd/prof: improve error messages

[apainintheneck]

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---

Small changes to provide better errors when using brew prof.

1. Provide an error message when the command is unknown.
2. Suggest running the command again with -- if there is an invalid option which might have been meant for a subcommand.

Before

/u/l/Homebrew (master|✔) $ brew prof updat
Error: undefined method `extname' for nil:NilClass
/usr/local/Homebrew/Library/Homebrew/dev-cmd/prof.rb:30:in `prof'
/usr/local/Homebrew/Library/Homebrew/brew.rb:93:in `<main>'

/u/l/Homebrew (master|✔) [1]$ brew prof list -r
Usage: brew prof [--stackprof] command [...]

Run Homebrew with a Ruby profiler. For example, brew prof readall.

      --stackprof                  Use stackprof instead of ruby-prof (the
                                   default).
  -d, --debug                      Display any debugging information.
  -q, --quiet                      Make some output more quiet.
  -v, --verbose                    Make some output more verbose.
  -h, --help                       Show this message.
Error: invalid option: -r

After

/u/l/Homebrew (improve-prof-errors|✔) $ brew prof updat
Usage: brew prof [--stackprof] command [...]

Run Homebrew with a Ruby profiler. For example, brew prof readall.

      --stackprof                  Use stackprof instead of ruby-prof (the
                                   default).
  -d, --debug                      Display any debugging information.
  -q, --quiet                      Make some output more quiet.
  -v, --verbose                    Make some output more verbose.
  -h, --help                       Show this message.

Error: Invalid usage: `updat` is an unknown command!

/u/l/Homebrew (improve-prof-errors|✔) [1]$ brew prof list -r
Usage: brew prof [--stackprof] command [...]

Run Homebrew with a Ruby profiler. For example, brew prof readall.

      --stackprof                  Use stackprof instead of ruby-prof (the
                                   default).
  -d, --debug                      Display any debugging information.
  -q, --quiet                      Make some output more quiet.
  -v, --verbose                    Make some output more verbose.
  -h, --help                       Show this message.
Error: invalid option: -r
Try `brew prof -- list -r` instead.

[BrewTestBot]

Review period will end on 2023-02-17 at 02:28:36 UTC.

[Rylan12]

This looks great, thanks!

[MikeMcQuaid]

Very nice! One suggestion (that probably violates brew style so may want to do manually).

[MikeMcQuaid]

Suggested change

	raise UsageError, "`#{cmd}` is a Bash command!"
	raise UsageError, "As `#{cmd}` is a Bash command it cannot be profiled with `brew prof`! Try `hyperfine` for benchmarking instead."

[apainintheneck]

I like this idea.

[apainintheneck]

/u/l/Homebrew (improve-prof-errors|✚1) [1]$ brew prof --version
Usage: brew prof [--stackprof] command [...]

Run Homebrew with a Ruby profiler. For example, brew prof readall.

      --stackprof                  Use stackprof instead of ruby-prof (the
                                   default).
  -d, --debug                      Display any debugging information.
  -q, --quiet                      Make some output more quiet.
  -v, --verbose                    Make some output more verbose.
  -h, --help                       Show this message.

Error: Invalid usage: `--version` is a Bash command!
Try `hyperfine` for benchmarking instead.

Wary of the 80 character limit I opted for this instead.

[BrewTestBot]

Review period ended.