Warn users with harmful path_helper calls

[derekprior]

El Capitan moves the path_helper call to zprofile, but our dotfiles
had already accounted for it being in zshenv where it was previously.

[geoffharcourt]

Correctly warned on my machine.

[geoffharcourt]

The warning message is missing the word path_helper on my screen output. Are the backticks trying to execute path_helper there?

[derekprior]

That's because I was so helpfully calling path_helper rather than displaying it.

[geoffharcourt]

One more issue: if zprofile doesn't exist, there's an error message:

❯ rcup
grep: /etc/zprofile: No such file or directory

[derekprior]

hm. I thought that's what --silet was supposed to fix.

[gabebw]

According to man grep on OS X, --quiet and --silent do the same thing:

 -q, --quiet, --silent
             Quiet mode: suppress normal output.  grep will only search a file until a match has been found, making searches potentially less expensive.

Do you mean --quiet --no-messages?

     -s, --no-messages
             Silent mode.  Nonexistent and unreadable files are ignored (i.e. their error messages are suppressed).

Is there a difference between OS X, *BSD, and Linux grep here? @thoughtbot/shell

[derekprior]

Updated. The flag I wanted was --no-messages

[gabebw]

Technically this doesn't require the quotes. But it doesn't really matter.

[gabebw]

I have no further input on the quality of this shell script.

[mike-burns]

The more portable way to write this is:

if grep path_helper /etc/zprofile >/dev/null 2>/dev/null; then

That will work on unix systems in addition to GNU.

[derekprior]

Looks like we're going in another direction.

[geoffharcourt]

Hi @derekprior I wanted to wait until we resolved the issues in #426 before making a call here.

[derekprior]

In any event - the code there will be more useful in displaying a better message.