Brew: `brew help bundle` runs `brew bundle` after tapping

[bartskowron]

Bug report

• [x] ran brew update and can still reproduce the problem?
• [x] ran brew doctor, fixed all issues and can still reproduce the problem?
• [x] ran brew config and brew doctor and included their output with your issue?

What you were trying to do (and why)

I was looking for some solutions on my problem with brew, and found some commands started with brew bundle.
Well, I never do copy&paste, so first I wanted to know what is the bundle. So, I simply typed: brew help bundled and all this happened...

What happened (include command output)

Command output

$ brew help bundle

==> Tapping homebrew/bundle

Cloning into '/usr/local/Homebrew/Library/Taps/homebrew/homebrew-bundle'...

remote: Enumerating objects: 13, done.

remote: Counting objects: 100% (13/13), done.

remote: Compressing objects: 100% (13/13), done.

remote: Total 5158 (delta 4), reused 1 (delta 0), pack-reused 5145

Receiving objects: 100% (5158/5158), 1.15 MiB | 2.79 MiB/s, done.

Resolving deltas: 100% (3019/3019), done.

Tapped 1 command (104 files, 1.5MB).

Error: No Brewfile found

  

What you expected to happen

I expected to get some information about a command bundle. Now, I know I should use brew bundle --help. I won't argue if this is convenient or not.
However, let me answer what I did not expect: Auto installation of the bundle!
This definitely should never happed for a help command.

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

brew help bundle

Output of brew config and brew doctor commands

doctor: Your system is ready to brew.

HOMEBREW_VERSION: 2.4.16
ORIGIN: https://github.com/Homebrew/brew
HEAD: 2a4c9f610e69b9fed1eec61ac2c53e4b11a32e4c
Last commit: 7 days ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 642b748a2f1029ee2afb0188a5ced5d543be4456
Core tap last commit: 2 hours ago
Core tap branch: master
HOMEBREW_PREFIX: /usr/local
HOMEBREW_CASK_OPTS: []
HOMEBREW_MAKE_JOBS: 4
CPU: quad-core 64-bit haswell
Homebrew Ruby: 2.6.3 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
Clang: 11.0 build 1103
Git: 2.28.0 => /usr/local/bin/git
Curl: 7.64.1 => /usr/bin/curl
macOS: 10.15.6-x86_64
CLT: 12.0.0.0.1.1597368733
Xcode: 11.7

[bartskowron]

Side comment: So how can I clean it up now? Just manually removing /usr/local/Homebrew/Library/Taps/homebrew/homebrew-bundle directory? There is no information how to uninstall this, and I never asked to install it.

[Rylan12]

bundle is an external command that comes from the homebrew-bundle tap. It lives in a separate repository so in order to use any of the bundle functionality you must tap (think git clone) the bundle repository. This includes seeing the help information which lives in the repository as well. Since bundle is an official tap, Homebrew automatically detects and "installs" it in order to show the help message.

So how can I clean it up now?

brew untap homebrew/bundle will remove bundle.

I agree, though, I don't think we should be automatically tapping things like this (even if they're official) because its unexpected for users. I'd, instead, suggest one of the following options when running brew help <cmd> where cmd comes from an external tap:

1. Display a message before/after tapping that says something like: "Tapping homebrew/<foo> to show help text for <cmd>. To untap, run brew untap homebrew/<foo>"
2. Prompt the user saying something like: "Do you want to tap homebrew/<foo>? This is necessary to display help test for <cmd> [Y/n]:"
3. Don't tap automatically and print a message saying: "To view help text for <cmd> you must tap homebrew/<foo> by running brew tap homebrew/<foo>

@bartskowron do you, as a user, have a preference for any of the above options? I, as a maintainer, like the first option (tap and give instructions for how to untap)

However, automatic tapping was clearly added for a reason so I will differ to other maintainers if there's a good reason to keep it this way.

[bartskowron]

As I understood correctly, the reason to add automatic tapping was due to possibility to have a nice template for any possible tap that could be found at the moment. This behaviour can be kept by moving fetching of the taps to brew update command (which is supported and enabled AFAIK). Then the search should be done based on already cached information.
This would be understandable from user point of view.

As speaking about the proposed options, I'm definitely opting for the second option. I have no doubts about it. The first option is acceptable, however I can imagine to get mad if this would happened in some circumstances (e.g. expensive roaming costs).
The third option is very manual. You have to type a way more characters than just simply pressing Enter ;-)

Thanks for the detailed explanation. I appreciate it :ok_hand:

[Rylan12]

As I understood correctly, the reason to add automatic tapping was due to possibility to have a nice template for any possible tap that could be found at the moment. This behaviour can be kept by moving fetching of the taps to brew update command (which is supported and enabled AFAIK). Then the search should be done based on already cached information.
This would be understandable from user point of view.

Maybe I'm not understanding what you mean exactly here. The reason that bundle was tapped automatically was so that you could view the help text. It's assumed, I think, that a user typing brew help bundle already knows that they want to tap homebrew-bundle so it saves them any extra work. Once it's been tapped, brew update will continue to update it just as it does homebrew-core and homebrew-cask

As speaking about the proposed options, I'm definitely opting for the second option. I have no doubts about it.

Good input—thanks! I would point out that we don't use user input like this anywhere else (that I can think of), so its possible that adding that functionality only here would be frowned upon. I'm not sure if we have a specific reason for this (for example, to make brew work in scripts that won't be able to provide this input).

The first option is acceptable, however I can imagine to get mad if this would happened in some circumstances (e.g. expensive roaming costs).

Good point. Noted!

The third option is very manual. You have to type a way more characters than just simply pressing Enter ;-)

Totally agree

[claui]

I would point out that we don't use user input like this anywhere else (that I can think of), so its possible that adding that functionality only here would be frowned upon. I'm not sure if we have a specific reason for this (for example, to make brew work in scripts that won't be able to provide this input).

Homebrew never prompts the user for anything except when escalating to root privileges.
It’s built that way with scriptability in mind.

I feel the key here is to meet user expectations.
People certainly don’t expect a help command to download things but neither is it supposed to _ask back_.

The first option is acceptable, however I can imagine to get mad if this would happened in some circumstances (e.g. expensive roaming costs).

@bartskowron The tap weighs about three megabytes, which is less than a single page of many websites. If a user is in situation where that’s a concern, they should certainly not interact with a package manager (which, by the way, also auto-updates).

[MikeMcQuaid]

Agreed with @claui's response. Closing, sorry.

[Rylan12]

Homebrew never prompts the user for anything except when escalating to root privileges.
It’s built that way with scriptability in mind.

Makes sense, thanks for the insight @claui

However, I do still think there's value in at least telling the user what is happening/how to untap. Any objections to adding a message like this to the output?

[Rylan12]

Actually, I'm going to reopen and repurpose this issue.

Running brew help bundle when homebrew-bundle isn't tapped does the following:

1. Run brew tap homebrew/bundle
2. Run brew bundle (which returns Error: No Brewfile found)

Regardless of whether bundle is automatically tapped, the user should ultimately get the help text (which is what they asked for)

Expected:

1. Run brew tap homebrew/bundle
2. Show output of brew help bundle

[maxim-belkin]

I find it strange that brew help X taps a repo. I think Homebrew should be failing if X command isn't available with an error message along the lines of Command X is not found. Please tap Z to install it. (which, I now see, is what @Rylan12 have proposed above in option 3). Everything will still be "scriptable".

[bartskowron]

Homebrew never prompts the user for anything except when escalating to root privileges.
It’s built that way with scriptability in mind.

I feel the key here is to meet user expectations.
People certainly don’t expect a help command to download things but neither is it supposed to _ask back_.

Very good point! After rethinking, I agree that scriptability should be a priority here.
This actually moves me to opt for a third option then. No problem! Its still a great solution and win-win.

The first option is acceptable, however I can imagine to get mad if this would happened in some circumstances (e.g. expensive roaming costs).
@bartskowron The tap weighs about three megabytes, which is less than a single page of many websites. If a user is in situation where that’s a concern, they should certainly not interact with a package manager (which, by the way, also auto-updates).

I made a shortcut, sorry for confusing! I can imagine to get mad at the moment of noticing the download and probably will be fine AFTER I realize that it was only 3MB that I didn't know about in a moment of the downloading start.

It's not necessary, can be stressful.

[Rylan12]

I'll copy @MikeMcQuaid's response in https://github.com/Homebrew/brew/pull/8653#issuecomment-689082064 here as well:

These are "official external commands" so this behaviour is intentional. Perhaps they should/could be migrated to Homebrew/brew instead but until then allowing brew bundle or brew services to work without extra intervention is desirable.