Upgrade of rsyslog with build-from-source fails if there is an existing config file

[logopk]

brew gist-logs <formula> link OR brew config AND brew doctor output

▶ brew config           
HOMEBREW_VERSION: 4.3.9-267-gdf27448
ORIGIN: https://github.com/Homebrew/brew
HEAD: df27448ea7f92a9f46a5b59b368c3f4b147df6fa
Last commit: 16 hours ago
Core tap HEAD: f148630ef831f3cbece5b01eb584f5431889c3ce
Core tap last commit: 15 hours ago
Core tap JSON: 16 Jul 06:01 UTC
Core cask tap JSON: 16 Jul 06:01 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_GITHUB_API_TOKEN: set
HOMEBREW_MAKE_JOBS: 8
HOMEBREW_SORBET_RUNTIME: set
Homebrew Ruby: 3.3.4 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.3.4/bin/ruby
CPU: octa-core 64-bit arm_firestorm_icestorm
Clang: 15.0.0 build 1500
Git: 2.39.3 => /Library/Developer/CommandLineTools/usr/bin/git
Curl: 8.6.0 => /usr/bin/curl
macOS: 14.5-arm64
CLT: 15.3.0.0.1.1708646388
Xcode: 15.4
Rosetta 2: false

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Verification

• My brew doctor output says Your system is ready to brew. and am still able to reproduce my issue.
• I ran brew update and am still able to reproduce my issue.
• I have resolved all warnings from brew doctor and that did not fix my problem.
• I searched for recent similar issues at https://github.com/Homebrew/homebrew-core/issues?q=is%3Aissue and found no duplicates.

What were you trying to do (and why)?

brew reinstall --build-from-source rsyslog

What happened (include all command output)?

==> Installing rsyslog
==> ./configure --enable-imfile --enable-usertools --enable-diagtools --disable-

==> make
==> make install
Error: An exception occurred within a child process:
RuntimeError: Will not overwrite /opt/homebrew/etc/rsyslog.conf

What did you expect to happen?

skip

    (etc/"rsyslog.conf").write <<~EOS
      # minimal config file for receiving logs over UDP port 10514
      $ModLoad imudp
      $UDPServerRun 10514
      *.* /usr/local/var/log/rsyslog-remote.log
    EOS

as there is already a more sophisticated conf file.

I know build-from-source is unsupported but is there a way to update the formula to skip this message?

Step-by-step reproduction instructions (by running brew commands)

brew update

brew upgrade --build-from-source rsyslog

I could fix this with 

brew upgrade --verbose --debug rsyslog
and option 2) ignore

but that ist tiresome

[cho-m]

Might be an issue due to using .write rather than special etc.install logic (which would create/modify rsyslog.conf.default if rsyslog.conf already exists).

Using a temporary file may help like in percona-server:

homebrew-core/Formula/p/percona-server.rb

Lines 163 to 169 in f4861d0

	(buildpath/"my.cnf").write <<~EOS
	# Default Homebrew MySQL server config
	[mysqld]
	# Only allow connections from localhost
	bind-address = 127.0.0.1
	EOS
	etc.install "my.cnf"

[logopk]

Hi, is there anyone in charge of this formula who would be able to fix this? Would it be sufficient for me to post a PR?

I've never mad a PR besides a bump...

[branchvincent]

#178928 will fix this

[logopk]

@branchvincent Thank you!