utils/github/actions: add format_multiline_string method

[nandahkrishna]

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---

Needed for Homebrew/actions#336, see @Bo98's comment:

Escaping works differently now so this doesn't work. The new way to do it is:

{name}<<{delimiter}
{value}
{delimiter}

For security reasons delimiter must be randomly generated and unique to each run (e.g. UUID v4). It should also be something that doesn't appear in the message. It may be worth having a new method in Homebrew/brew.

See https://github.com/actions/toolkit/blob/b00a9fd033f4b30f2355acd212f531ecbbb9b38f/packages/core/src/file-command.ts#L27-L47 for an example implementation in JavaScript.

[BrewTestBot]

Review period skipped due to critical label.

[carlocab]

Are you planning to use this?

[nandahkrishna]

Yes, I used it here (line 30):

if name.include?(delimiter) || value.include?(delimiter)
  raise Error, "`name` and `value` must not contain the delimiter"
end

[carlocab]

Sorry, I meant: do you need to rescue this anywhere? Otherwise you could just do

  raise "`name` and `value` must not contain the delimiter"

[nandahkrishna]

Ah, I guess I could've just done that 🤦🏻‍♂️

[carlocab]

Not too late to change it!

[carlocab]

Nice work!

[MikeMcQuaid]

Nice work @nandahkrishna!

[msarm]

@nandahkrishna - It looks like the above change is causing an issue when I try to install the homebrew on M2 Silicon.

Error=: HEAD is now at 27bb6ff Merge pull request #15002 from nandahkrishna/actions-multiline-envfile

The output indicates that the HEAD of the current branch has been updated to a merge commit that merged the changes from a pull request created by the user "nandahkrishna".

---

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

==> Checking for sudo access (which may request your password)...
==> This script will install:
/opt/homebrew/bin/brew
/opt/homebrew/share/doc/homebrew
/opt/homebrew/share/man/man1/brew.1
/opt/homebrew/share/zsh/site-functions/_brew
/opt/homebrew/etc/bash_completion.d/brew
/opt/homebrew

Press RETURN/ENTER to continue or any other key to abort:
==> /usr/bin/sudo /usr/sbin/chown -R bhawaniya:admin /opt/homebrew
==> Downloading and installing Homebrew...
HEAD is now at 27bb6ff Merge pull request #15002 from nandahkrishna/actions-multiline-envfile
Error: Failed to download https://formulae.brew.sh/api/formula.jws.json!
Error: Failure while executing; /usr/bin/env /opt/homebrew/Library/Homebrew/shims/shared/curl --disable --cookie /dev/null --globoff --user-agent Homebrew/4.0.6\ \(Macintosh\;\ arm64\ Mac\ OS\ X\ 13.2.1\)\ curl/7.86.0 --header Accept-Language:\ en --fail --progress-bar --location --remote-time --output /Users/bhawaniya/Library/Caches/Homebrew/api/formula.jws.json --compressed --speed-limit 100 --speed-time 5 --progress-bar --silent https://formulae.brew.sh/api/formula.jws.json exited with 22.

[msarm]

Installs now! Thanks

[nandahkrishna]

@msarm The error you're seeing is unrelated to this PR, it's probably a network issue. Please try using the installer again and check the Discussions page for similar issues.